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1.
J Cell Biol ; 28(2): 145-53, 1966 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-4958170

RESUMEN

The effect of strychnine sulfate and light on pigmentation in the ciliate protozoan Blepharisma undulans has been determined. Upon exposure of cells to strychnine, the pigment granules become loosened from their surrounding membranes. Eventually these membranes break and the granules are simultaneously released from the cell. At the cell surface, a fusion occurs between adjacent membraneless granules with the incorporation of membrane fragments. This fusion of granules and membrane fragments results in the formation of a pigmented "capsule" around the organism. After elimination of the pigment, the granule membranes remaining in the cytoplasm fuse to form apparently empty vesicles. Other cell organelles are generally undisturbed. A similar situation occurs upon exposure of cells to artificial light for 12 to 18 hr, however, the slow elimination of granules from the cells under these conditions does not result in the formation of a pigmented "capsule." The possible mechanisms of these reactions are discussed.


Asunto(s)
Cilióforos/efectos de los fármacos , Luz , Pigmentación , Estricnina/farmacología , Microscopía , Microscopía Electrónica
2.
J Cell Biol ; 47(3): 568-76, 1970 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-5497538

RESUMEN

Exposure of Tetrahymena pyriformis to 7,500 or 10,000 psi of hydrostatic pressure for 2, 5, or 10 min intervals results in a change in cell shape and ciliary activity. Shape changes occur concurrently with a degradation of longitudinal microtubules in a posterior to anterior direction. High pressure also causes a disruption of ciliary activity. Fine structural analysis reveals a breakdown (presumably microtubule depolymerization) of the central ciliary microtubules. The depolymerization begins at the junction of the central ciliary microtubules with the axosome and progresses distally along the ciliary shaft for a distance of about 0.5 micro.


Asunto(s)
Cilios/citología , Animales
3.
Science ; 168(3935): 1097-8, 1970 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-5441682

RESUMEN

Cigarette smoke residue is ciliatoxic to Tetrahymena pyriformis. Principal sites of activity are the mitochondria of the cell. The internal membranes of the mitochondria are degraded with time, correlating well with loss of ciliary activity and cell death.


Asunto(s)
Cilios/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Fumar , Animales , Sitios de Unión , Microscopía Electrónica , Tetrahymena/citología
4.
Materials (Basel) ; 11(5)2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29693591

RESUMEN

The process of isomorphic inoculation relies on precise selection of inoculant alloys for a given system. Three alloys, Ti-10Al-25Nb, Ti-25Al-10Ta, and Ti-47Ta (at %) were selected as potential isomorphic inoculants for a Ti-46Al alloy. The binary Ti-Ta alloy selected was found to be ineffective as an inoculant due to its large density difference with the melt, causing the particles to settle. Both ternary alloys were successfully implemented as isomorphic inoculants that decreased the equiaxed grain size and increased the equiaxed fraction in their ingots. The degree of grain refinement obtained was found to be dependent on the number of particles introduced to the melt. Also, more new grains were formed than particles added to the melt. The grains/particle efficiency varied from greater than one to nearly twenty as the size of the particle increased. This is attributed to the breaking up of particles into smaller particles by dissolution in the melt. For a given particle size, Ti-Al-Ta and Ti-Al-Nb particles were found to have a roughly similar grain/particle efficiency.

5.
Eur J Cell Biol ; 40(2): 203-9, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3086097

RESUMEN

Ciliated epithelial cells from rabbit trachea were employed to examine the role of Ca2+ in the regulation of ciliary motility. Tracheal explants and outgrowths were maintained in culture, and ciliary frequency was determined using a photomultiplier interfaced with a spectrum analyzer capable of Fast Fourier transform analysis. Relative cellular Ca2+ levels were determined by measuring 45Ca2+ uptake and efflux. Elevated cellular Ca2+, from exposure to 10(-5) M calcium ionophore A23187, led to an increase in ciliary frequency followed by inhibition of motility after prolonged treatment. A decrease in ciliary frequency was observed upon lowering intracellular Ca2+ by exposing the epithelium to 1 mM EGTA. Exposure of ciliated cells to 10(-4) M trifluoperazine resulted in inhibition of ciliary motility, a result suggesting a possible role for calmodulin- or phospholipid-sensitive Ca2+-dependent protein kinases in ciliary function. These results support the hypothesis that intracellular Ca2+ is actively involved in modulating the frequency of ciliary beat.


Asunto(s)
Calcio/fisiología , Cilios/fisiología , Animales , Calcimicina/farmacología , Ácido Egtácico/farmacología , Epitelio/ultraestructura , Femenino , Técnicas In Vitro , Cinética , Masculino , Movimiento , Conejos , Tráquea/ultraestructura , Trifluoperazina/farmacología
6.
Eur J Cell Biol ; 29(2): 200-8, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6832166

RESUMEN

Ciliated outgrowths from cultured rabbit tracheal epithelium have been characterized with scanning and transmission electron microscopy and the ciliary frequencies measured. Outgrowth surface cells change in morphology from columnar to cuboidal to squamous shapes in their progression away from the explant. The ciliated cells retain the organization of their cilia in a cluster usually centrally on the apical cell surface. Closest to the explant the nonciliated surface of ciliated cells develops extensive microvilli. Ciliary frequencies are comparable to those observed in fresh tracheal epithelium with means of 50 cells per explant ranging from 11 to 23 beats per second. For most cultures examined no correlation exists between ciliary frequency and cell distance from the explant. The goblet cells loose their ability to synthesize the characteristic mucus granules and can only be identified by the absence of cilia. Surface cells are supported by an underlying layer of discontinuous cells and connective tissue fibers. The characteristics of an outgrowth suggest that development occurs through migration of differentiated cells from the explant rather than differentiation of cell types from migrating basal cells.


Asunto(s)
Cilios/ultraestructura , Tráquea/ultraestructura , Animales , Diferenciación Celular , Técnicas de Cultivo , Epitelio/ultraestructura , Microscopía Electrónica de Rastreo , Conejos
7.
Int J Parasitol ; 31(11): 1275-7, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11513898

RESUMEN

The protection from malaria afforded by sickle haemoglobin (and certain other haemoglobinopathies) suggests that it may be possible to utilise a common property that their erythrocytes share with both malaria-infected erythrocytes and senescent erythrocytes to develop a vaccine. All three conditions cause clustering of a specific protein molecule, band 3, on their erythrocyte's surface and this protein, when present on senescent erythrocytes at least, results in the immune recognition and removal of these by naturally occurring antibodies. It is hypothesised that if an up-regulated immune response to this protein on sickle cells is responsible for the benefit afforded to malaria patients then a vaccine using antigenic band 3 peptides may provide similar protection.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/inmunología , Eritrocitos/parasitología , Hemoglobina Falciforme/inmunología , Vacunas contra la Malaria , Malaria/prevención & control , Plasmodium falciparum/inmunología , Animales , Malaria/genética , Malaria/inmunología , Plasmodium falciparum/genética
8.
Am J Med Genet ; 33(3): 290-8, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2801763

RESUMEN

A laboratory-maintained colony of English springer spaniel dogs heterozygous for a putative autosomal recessive immotile-cilia syndrome (ICS) has been studied. Matings between dogs thought to be heterozygous for ICS resulted in 22 pups, five (three males and two females) of which were homozygous for ICS. Four of the five ICS-affected dogs had chronic rhinitis and bronchopneumonia. The other dog had a serious nasal discharge and died at 10 days. Four dogs had situs inversus totalis (kartagener syndrome), and the two males of reproductive age were azoospermic. In the two ICS dogs studied for ciliary function, in vivo mucociliary clearance was absent, and in vitro ciliary beat was rarely observed and of low frequency. Scanning and transmission electron microscopy disclosed the same lesions in respiratory cilia from all dogs with ICS, including random orientation and partial outer dynein arm deficiency. Four of five dogs with ICS had dilated lateral ventricles. One female pup with neonatal rhinitis and bronchopneumonia, situs solitus, and dilated lateral ventricles was presumed to be homozygous for ICS, but died without functional or structural confirmation of defective respiratory cilia. An autosomal recessive mode of inheritance for the ciliary defects and respiratory signs of ICS in these dogs is proposed.


Asunto(s)
Trastornos de la Motilidad Ciliar/veterinaria , Enfermedades de los Perros/genética , Animales , Cilios/ultraestructura , Trastornos de la Motilidad Ciliar/complicaciones , Trastornos de la Motilidad Ciliar/genética , Perros , Genes Recesivos , Humanos , Infertilidad Masculina/complicaciones , Masculino , Microscopía Electrónica de Rastreo , Depuración Mucociliar , Linaje , Semen/análisis , Situs Inversus/complicaciones , Testículo/patología , Testosterona/sangre
9.
Ann Thorac Surg ; 24(1): 62-7, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-879885

RESUMEN

This study, developed for the purpose of establishing an appropriate protocol for general follow-up of the paced patient, is based on clinical experience with patients derived from diverse specialties, geographical locations and protocol preferences. The analysis represents a four-year study of the transtelephonic follow-up of 1,705 implanted cardiac pacers, which represents 44,616 pacer-months of experience. There were 340 system malfunctions, 41% (141) due to battery exhaustion and 59% (199) due to other causes. Of all observed system failures 9.7% (33) occurred within 1 month of implantation, with the rate declining sharply thereafter until battery failures began to occur at approximately the twenty-fourth month. Only 10.9% (37) of all system failures were accompanied by clinical symptoms. Of the clinical failures, 62% (23) occurred in patients who were tested at intervals greater than 10 weeks. Our analysis indicates that testing should be performed weekly for the first month following lead manipulation. Thereafter, tests should be performed at 8- to 10-week intervals for the first 24 months of pacemaker life. During the third postimplant year tests should be conducted more frequently, depending on the energy source of the generator.


Asunto(s)
Arritmias Cardíacas/terapia , Marcapaso Artificial , Ingeniería Biomédica , Estudios de Seguimiento , Humanos
10.
In Vitro Cell Dev Biol Anim ; 30A(3): 168-80, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25939165

RESUMEN

The morphologic and functional properties of explant out-growth cells and epithelial cells isolated from swine trachea epithelium by proteolysis were examined. A mixed population of ciliated, serous, and basal cells, obtained from out-growths, from proteolysis of trachea epithelium, and from unattached explants in organ culture, all yielded cell cultures that werecomposed almost entirely of mucus-secreting cells. When the cells were grown in primary or secondary culture on a modified collagen matrix in supplemented HAM:DMEM (1:1) medium they expressed a mucus-secreting phenotype with numerous mucus granules at various stages of maturation and incorporated [3H]GlcN and 35SO4 into secreied mucin glycoproteins. Results obtained in these studies suggest that extensive transdifferentiation of ciliated and serous cells to mucus-secreting-cells occurs after the release and during subsequent attachment and culture. Ciliated cells containing mucus granules were seen in various stages of cilia resorption. Basal cells containing mucus granules were also frequently observed. The number of mucus-secreting cells and the synthesis of mucin glycoproteins increased dramatically with time of attachment and culture, whereas cell proliferation, population doubling time of 72 h, and incorporation of [3H]-thymidine into DNA increased much more slowly. The number of mucus-secreting cells correlated closely with the level of secretion of mucin glycoproteins. Taken collectively, these studies help to elucidate the transdifferentiation process, which dramatically increases the number of mucus-secreting cells after disruption and release of epithelial cells from swine tracheobronchial epithelium. A similar mechanism involving disruption of the extracellular matrix may be involved in the stimulation of hypersecretion of mucus and mucin glycoproteins by chemical and infections irritants.


Asunto(s)
Transdiferenciación Celular , Tráquea/citología , Animales , Proliferación Celular , Células Cultivadas , Colágeno/metabolismo , Endopeptidasas/farmacología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Mucinas/metabolismo , Moco/metabolismo , Porcinos
11.
Talanta ; 20(10): 987-92, 1973 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18961376

RESUMEN

A method is presented for the determination of long-chain quaternary ammonium salts, tertiary amines and secondary amines in water or aqueous raffinates, based on their extraction and fluorimetric determination as amine salts with Eosine Yellowish in toluene-hexanol (4:1) as solvent. No interferences were obtained from metal ions, or chloride, nitrate or phosphate ions when a back-washing method was applied to the sample extract. The method allows the determination of long-chain tertiary amines down to 4 ppM.

12.
Tissue Cell ; 8(3): 479-90, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-185747

RESUMEN

The alimentary canal of Daphnia pulex consists of a tube-shaped foregut, a midgut (mesenteron) with an anterior pair of small diverticula, and a short hindgut. The foregut and hindgut are structurally similar. Each is formed by a low cuboidal epithelium 5 mum tall and lined with a chitinous intima. The midgut wall consists of a simple epithelium resting on a thick beaded basal lamina which is surrounded by a spiraling muscularis. Anteriorly the midgut cells are columnar in shape being 30 mum in height each having a basal nucleus, anteriorly concentrated mitochondria and in apical border of long thin microvilli. Posteriorly the midgut cells become progressively shorter so that in the posteriormost region of the midgut the cells are 5 mum tall and cuboidal in shape. The microvilli concomitantly become shorter and thicker. All mesenteron cells contain the usual cytoplasmic organelles. The paired digestive diverticula are simple evaginations of the midgut. The wall of each consists of a simple epithelium of cuboidal cells 25 mum in height, each with a brushed border of long thin microvilli. Enzyme secretion appears to be holocrine in mode and not confined to any one region of the mesenteron though definitely polarized anteriorly. The thin gut muscularis encircles the entire length of the midgut and caeca. Thick and thin filaments appear to be in a 6:1 ratio.


Asunto(s)
Daphnia/ultraestructura , Animales , Membrana Celular/ultraestructura , Núcleo Celular/ultraestructura , Sistema Digestivo/ultraestructura , Retículo Endoplásmico/ultraestructura , Células Epiteliales , Epitelio/ultraestructura , Esófago/ultraestructura , Aparato de Golgi/ultraestructura , Cuerpos de Inclusión/ultraestructura , Uniones Intercelulares/ultraestructura , Lisosomas/ultraestructura , Mitocondrias/ultraestructura , Músculos/ultraestructura , Miofibrillas/ultraestructura
13.
Med Hypotheses ; 54(5): 723-5, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10859676

RESUMEN

The term reactive arthritis (ReA) was first used in 1969 to describe sterile joint disease that follows infection elsewhere in the body. This is an attempt to explain the immunological basis of this disease, give a rationale for the presence of a single bacterial antigen in the involved joints, explain why the class I MHC molecule HLA-B27 is necessary and to suggest possible therapy. This paper proposes an anti-idiotypic (anti-id) model for this disease where a bacterial lipopolysaccharide (LPS) epitope is recognized by idiotypic (Id) T cell receptors and antibody Fab immune recognition surfaces (IRS) which have the immunologic appearance of an antigen on the synovial surface. These Id immune effectors utilize an HLA-B27 molecule to present their IRS on their surface, which results in an anti-id response that can also target the synovial antigen. The anti-id IRS have the immunologic appearance of LPS and their detection in the arthritic joint falsely suggests the presence of bacterial LPS. Evidence is presented which supports this reactive arthritis model in which there is a synovial antigen that is attacked by an anti-id response against the LPS of arthritogenic bacteria. Therapeutic vaccination is supported by this hypothesis.


Asunto(s)
Artritis Reactiva/inmunología , Autoantígenos/inmunología , Lipopolisacáridos/inmunología , Membrana Sinovial/inmunología , Anticuerpos Antiidiotipos/inmunología , Humanos , Modelos Biológicos , Prohibitinas
14.
15.
Med Hypotheses ; 37(1): 16-9, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1349151

RESUMEN

In AIDS a complementary interface between the HIV virus and the CD4 molecule of the T4 lymphocyte suggest a possible cause of immune self-recognition. Because of this complementarity, an anti-idiotypic immune response to the CD4 attachment area of HIV should result in an autoimmune reaction to CD4 positive lymphocytes. Experimental demonstration of such an immune recognition model by autoreactive lymphocytes is presented and a hypothetical immune response unit is suggested.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Autoinmunidad , Modelos Biológicos , Anticuerpos Antiidiotipos/inmunología , Linfocitos T CD4-Positivos/inmunología , Antígenos VIH/inmunología , Humanos , Idiotipos de Inmunoglobulinas/inmunología , Linfocitos T Citotóxicos/inmunología
16.
Med Hypotheses ; 31(4): 303-7, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1972537

RESUMEN

An immune control system is proposed which is made up of a pair of idiotypic T4 and T8 cells which recognize self-antigen, and a pair of anti-idiotypic T4 and T8 cells which recognize those idiotypic receptors. The protective and destructive elements of the control cells and their induced immunoglobulins are in equilibrium, allowing self-recognition and tolerance. One of the self-antigens monitored by the system is CD4, the T4 surface marker and also the HIV attachment site. In AIDS the HIV attachment antigen is immunologically identical to one of the CD4 control cell receptors. This disrupts the equilibrium of the system causing chronic T4 cell destruction.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Modelos Biológicos , Antígenos de Diferenciación de Linfocitos T , Autoantígenos , Antígenos CD4 , Linfocitos T CD4-Positivos/inmunología , Antígenos CD8 , Humanos , Linfocitos T/inmunología
17.
Med Hypotheses ; 41(5): 445-9, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7908400

RESUMEN

An immune modulation complex is proposed which recognizes and is driven by an MHC presented epitope of the CD4 molecule present on the surface of up regulated CD4+ lymphocytes. Immune modulation is affected by both CD4 lymphocyte destruction and impairment of their potential for immune recognition. These two processes are carefully controlled by an idiotypic, anti-idiotypic feedback mechanism. The CD4 tropic area of HIV impersonates some components of that feedback loop resulting in increased CD4 lymphocyte destruction.


Asunto(s)
VIH/inmunología , Inmunidad/fisiología , Animales , Antígenos CD4 , Linfocitos T CD4-Positivos/inmunología , Infecciones por Coxsackievirus/inmunología , Retroalimentación , Infecciones por VIH/inmunología , Humanos , Modelos Biológicos , Miocarditis/inmunología , Linfocitos T Citotóxicos/inmunología
18.
Arch Environ Health ; 34(1): 5-11, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-434927

RESUMEN

The effects of tobacco cigarette smoke residues on rings of rabbit tracheal epithelium in organ culture were examined. Residue from cigarette smoke was collected through continuous suction and the residue from one cigarette was used for each two tracheal rings. Epithelium exposed to residue showed cellular desquamation, initially of only scattered columnar cells. As exposure time increased the entire columnar cell layer was lost, resulting in exposure of basal cells to residue. Columnar cell loss occurred through breakdown of intercellular junctions. Alteration was also observed in columnar cell mitochondria, cilia, and microvilli. Loss of columnar cells and subsequent exposure of basal cells to tobacco smoke residue may account for the hyperplasia and metaplasia observed by other investigators after long-term in vivo exposure of tracheal epithelium to cigarette smoke.


Asunto(s)
Nicotiana , Plantas Tóxicas , Humo , Tráquea/ultraestructura , Animales , Cilios/ultraestructura , Técnicas de Cultivo , Epitelio/ultraestructura , Microvellosidades/ultraestructura , Mitocondrias/ultraestructura , Dilatación Mitocondrial , Conejos
19.
Case Rep Otolaryngol ; 2012: 981375, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23198229

RESUMEN

A 32-year-old woman presented to the endocrinology clinic with recent onset galactorrhoea. Investigations revealed raised prolactin levels. An MRI scan demonstrated a normal pituitary gland, and an incidental finding of sphenoid sinusitis with expansion of the sphenoid sinus was thought to be due to a mucocele. It is postulated that either the direct local pressure by the mucocele or localised inflammation secondary to sinusitis might cause hyperprolactinaemia. The patient underwent endoscopic surgery to drain the mucocele, after which her galactorrhoea resolved. A review of the literature reveals only one previously documented case of sinusitis causing hyperprolactinaemia and galactorrhoea.

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