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1.
J Chem Neuroanat ; 81: 42-47, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28159658

RESUMEN

We studied the expression of vitamin D receptor and of vitamin D binding protein in the rat vomeronasal organ. With immunofluorescence, in situ hybridization and with reverse transcriptase PCR we found both proteins in sensory as well as in non-sensory cells. Sensory neurons contained immunoreactivity for vitamin D3 receptor in nuclei, in portions of the cytoplasm, and in apical dendrites and their microvilli. Vitamin D binding protein was observed in sensory neuron axons and cytoplasm, mostly confined to dendrites. Colocalization appeared in the contact zone of supporting cells and sensory dendrites. Both proteins were also found in single ciliated cells within the non-sensory epithelium. Vitamin D binding protein was also localized in secretory vesicles in a portion of the vomeronasal glands. Our findings suggest that the rat vomeronasal organ is a vitamin D target.


Asunto(s)
Sistemas de Liberación de Medicamentos , Receptores de Calcitriol/metabolismo , Proteína de Unión a Vitamina D/metabolismo , Vitamina D/metabolismo , Órgano Vomeronasal/metabolismo , Animales , Sistemas de Liberación de Medicamentos/métodos , Femenino , Masculino , Mucosa Olfatoria/química , Mucosa Olfatoria/efectos de los fármacos , Mucosa Olfatoria/metabolismo , Ratas , Ratas Wistar , Receptores de Calcitriol/análisis , Células Receptoras Sensoriales/química , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Vitamina D/administración & dosificación , Proteína de Unión a Vitamina D/análisis , Órgano Vomeronasal/química , Órgano Vomeronasal/efectos de los fármacos
2.
J Chem Neuroanat ; 77: 19-23, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27085688

RESUMEN

Olfactory marker protein (OMP) may act as a modulator within the olfactory signal-transduction cascade. It has also been shown to have some importance in development of olfactory sensory organs. Here we used high resolution immunocytochemistry to localize OMP in the rat vomeronasal organ (VNO). Immunofluorescence for OMP was abundant in cilia and in apical dendrites of sensory cells, mostly associated with intraepithelial capillaries. Perikarya were stained to a lesser extent while intense OMP immunoreactivity was seen in axons of sensory neurons. Single cells within the non-sensory portion of the VNO exhibited intense OMP immunofluorescence in apical cilia and weak cytoplasmic staining. Some of the exocrine cells in the vomeronasal glands contained OMP positive secretory granules. Electron microscopy revealed that non-sensory ciliated cells had short rod like kinocilia as well as microvilli. These cells contained secretory vesicles. Their basal portion was in close apposition to nerve endings. Our findings suggest that the sensory part of the VNO contains OMP positive sensory neurons and that the non-sensory epithelium may contain secondary sensory cells. In addition OMP may be liberated from secretory glands into vomeronasal secretions.


Asunto(s)
Proteína Marcadora Olfativa/biosíntesis , Órgano Vomeronasal/metabolismo , Animales , Capilares/citología , Capilares/metabolismo , Capilares/ultraestructura , Cilios/metabolismo , Cilios/ultraestructura , Citoplasma/metabolismo , Citoplasma/ultraestructura , Dendritas/metabolismo , Dendritas/ultraestructura , Femenino , Inmunohistoquímica , Masculino , Proteína Marcadora Olfativa/genética , Mucosa Olfatoria/metabolismo , Mucosa Olfatoria/ultraestructura , Ratas , Ratas Wistar , Células Receptoras Sensoriales/metabolismo , Células Receptoras Sensoriales/ultraestructura , Órgano Vomeronasal/ultraestructura
3.
Dtsch Med Wochenschr ; 137(51-52): 2722-8, 2012 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-23233304

RESUMEN

Johann Wolfgang von Goethe was one of the most renowned German poets of the late Age of Enlightenment. However, his engagement went far beyond literature especially relating to politics and natural science. Goethe, primarily trained as a lawyer, developed his own theory of colors and even challenged the concepts of Isaac Newton. His discovery of the human intermaxilary bone questioned all the dogmas of the religious-minded world of the 18th century. Together with the anatomy professor Justus Christian Loder, Goethe performed comparative anatomy and proved the conceptual uniformity of humans and animals on 27 March 1784. Even though, Félix Vicq d'Azyr described the intermaxilary bone simultaneously in Catholic France, Goethe's findings were politically accepted due to the liberal Protestantism of the Duchy of Weimar. Nevertheless, leading anatomists of the century (Johann Friedrich Blumenbach, Petrus Camper and Samuel Thomas v. Soemmerring) mainly rejected Goethe's postulates which led to a delayed publication in 1820; almost 36 years after writing his original manuscript. Today, Goethe's discovery is known to be a fundamental basis for the development of Charles Darwin's theory of phylogenetic evolution. Nowadays, the Department of Anatomy contains the Museum Anatomicum Jenense which was founded by the Duke of Weimar, Carl August and Goethe and entails Goethe's premaxillary bones as its main attraction. The University values the cultural heritage of Goethe's contribution to Medicine and provides access to the collection to the public and generations of medical students. Still today Goethe's legacy is noticeable in the halls of the Alma Mater Jenensis.


Asunto(s)
Anatomía Comparada/historia , Manuscritos Médicos como Asunto/historia , Maxilar/anatomía & histología , Medicina en la Literatura , Poesía como Asunto/historia , Investigación/historia , Universidades/historia , Alemania , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia Antigua , Humanos
4.
Cell Mol Biol (Noisy-le-grand) ; 47 Online Pub: OL209-34, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11936869

RESUMEN

Novel chromogenic N-arylmethyl-aniline-substrates of the general formula R-NH-CH2C6H5-n-Xn (X = OH, NHR) for the localization of peroxidatic activity/hydrogen peroxide were synthesized in two steps from starting amines and aromatic aldehydes. When using 1,2-dinucleophiles (e.g. diaminobenzidine) as starting material there may be limitations resulting from dominant altemative reaction courses (amino-imines vs bis-imines) or tautomerism (amino-imines vs benzimidazolines). This has been investigated in a model study on 1,2-phenylendiamine. All substrates were evaluated for application in histochemistry, electrophoresis, colorimetry and electron microscopy. Thus, 1/ endogenous peroxidatic activity in native cryotome sections of Wistar rats was stained. One selected reagent was used for immuno-histochemical demonstration of vimentine and applied for laser microscopy at 543 nm as well. 2/ Electro-blotted dilution series of horseradish peroxidase were stained and reagents ranked according to their sensitivity. 3/ In test tube experiments precipitation behavior, color and solubility of precipitates was investigated. 4/The chromogens are capable of forming electron opaque final reaction products by way of increased osmiophilicity of the specific reaction product or/and by complexation of electron dense metals as demonstrated by electron microscopical investigations. As a result, two novel reagents derived from 1,2-phenylendiamine and 2-aminophenol are recommended especially for electron microscopy: The discrimination between internum and extemum of specific granules after osmium tetroxide treatment is resolved clearly as compared with results obtained with the standard Kamovsky protocol.


Asunto(s)
Compuestos Cromogénicos/química , Compuestos Cromogénicos/síntesis química , Peróxido de Hidrógeno/metabolismo , Metales/metabolismo , Bases de Schiff/química , Bases de Schiff/síntesis química , Animales , Bencilaminas/síntesis química , Bencilaminas/química , Diseño de Fármacos , Femenino , Masculino , Estructura Molecular , Peróxidos/metabolismo , Ratas , Ratas Wistar
5.
Cell Mol Biol (Noisy-le-grand) ; 46(7): 1191-212, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11075949

RESUMEN

For staining of peroxidase activity routinely employed 3-amino-9-ethylcarbazole 1 (AEC) was chemically modified in order to obtain chromogenic enzyme substrates with improved staining properties. In conclusion of systematically structure/staining considerations of a series of novel substrates, it can be generalized that the performance of traditional chromogenic peroxidase amine-substrates is accessible an considerably improvement in terms of sensitivity and adaptibility for various application purposes (solubility and color of the reaction product, electron dense and osmiophilic properties, ...) by attachment of chelating N-benzyl-moieties making available highly efficient the well known metal catalytic effect in a proposed intramolecular way. Thus, the model compounds 3(arylmethyl)amino-9-ethyl-carbazole 4 and 3,6-bis-(arylmethyl)amino-9-ethyl-carbazole 7 were synthesized by condensation of 3-amino-9-ethylcarbazole 1 (AEC) or the corresponding 3,6-diamine 5 with aromatic aldehydes 2. The resulting Schiff bases 3 and 6 were subsequently reduced with sodium borohydride. The obtained benzylamines 4 and 7 were examined as chromogenic substrates: 1) qualitatively in test tube experiments concerning color, precipitation behavior and solubility of the precipitates, 2) quantitatively by means of electroblotted dilution series of horseradish peroxidase, and finally in a biological environment for the localization of endogenous peroxidasic activity 3) in native cryotome tissues of Wistar rats. 4) The usefulness of the new approach for electron microscopy was revealed, too. Thus the discrimination between internum and externum of specific granules after osmium tetroxide contrastate was higher if compared with results obtained by the Karnovsky protocol. The wide spread variation of substitution patterns of the novel reagents gave reason for structure-reactivity considerations and ongoing leading structures. The stereochemical and electronic factors as well as competing reaction pathways governing the reaction course are briefly discussed. In addition, the metal associating reagents are highly effective in oxidative side-coupling reactions with aromatic amine or phenol-additives exemplified here by means of 4-amino-N,N-diphenylamine. The reagents 4 and 7 are obtainable in a simple in situ synthesis, too, offering in principle a 'chemical construction unit'. The demonstrated approach is of general interest for bioanalytical applications offering an access to potentially novel chromogens and electron opaque markers for the detection of peroxidasic activity/hydroperoxides or related redox enzyme systems.


Asunto(s)
Carbazoles/metabolismo , Quelantes/metabolismo , Compuestos Cromogénicos/metabolismo , Histocitoquímica/métodos , Peroxidasa/análisis , Peroxidasa/metabolismo , Animales , Carbazoles/síntesis química , Carbazoles/química , Quelantes/síntesis química , Quelantes/química , Precipitación Química , Compuestos Cromogénicos/síntesis química , Compuestos Cromogénicos/química , Color , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/ultraestructura , Electroforesis en Gel de Poliacrilamida , Eosinófilos/citología , Eosinófilos/enzimología , Eosinófilos/ultraestructura , Peróxido de Hidrógeno/metabolismo , Intestinos/citología , Intestinos/enzimología , Masculino , Microscopía Electrónica , Estructura Molecular , Ratas , Ratas Wistar , Sensibilidad y Especificidad , Coloración y Etiquetado/métodos , Estómago/citología , Estómago/enzimología
6.
Scanning ; 22(4): 263-70, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10958394

RESUMEN

In the present work, the authors investigated ultrastructural changes as well as the reproduction behaviour of preselected single CHO-K1 cells exposed to 170 femtosecond laser pulses at different power output levels in comparison with cells outside the illumination volume. The ultrashort laser pulses were provided by an 80 MHz Ti:sapphire laser at 780 nm. The cells were scanned ten times with a scan rate of 1/16 s(-1). Single CHO-K1 cells exposed to low mean power of 2 mW revealed no significant changes in ultrastructure after laser exposure. In some cases, changes of mitochondria with slight disordering of cristae were found. Cytoplasm was filled with vesicles that seemed to be released from Golgi stacks. Cells irradiated with higher powers demonstrated more dramatic changes in ultrastructure. A considerable number of swollen mitochondria in conjunction with loss of cristae was observed. The main event of mitochondrial changes was the formation of electron dense bodies in the mitochondrial matrix. In addition, lumen of endoplasmatic reticulum was enlarged. Highest applied mean laser power of 12.5 mW lead to complete destruction of mitochondria and their transformation to electron dense structures containing membrane material. Compared with cell targets irradiated with 2 mW mean power, the release of vesicles from Golgi stacks seemed to be rather moderate. Cells localised outside the laser beam revealed no ultrastructural changes. Low mean laser power at 2 mW was unable to impair the reproduction behaviour of CHO-K1 cells. At higher laser power output levels, CHO-K1 cells started to delay cell division. At 12.5 mW, no cell division occurred. The obtained results may be helpful in recommending parameters for safe femtosecond laser microscopy of living specimens.


Asunto(s)
División Celular/efectos de la radiación , Citoplasma/ultraestructura , Aparato de Golgi/ultraestructura , Rayos Láser , Mitocondrias/ultraestructura , Animales , Células CHO , Cricetinae , Citoplasma/efectos de la radiación , Aparato de Golgi/efectos de la radiación , Microscopía Electrónica , Mitocondrias/efectos de la radiación
7.
Histochem Cell Biol ; 106(4): 431-6, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8911972

RESUMEN

Glucose-6-phosphatase (G6Pase) activity has been determined in periportal and pericentral areas of the liver of normal male rats. Measurements were performed on unfixed cryostat sections mounted on semipermeable membranes. In the present study, the oxidized primary reaction product of a cerium-based histochemical method [Ce(IV)perhydroxyphosphate] instead of the final reaction product after a second-step incubation was measured. For quantification of the amount of Ce(IV)perhydroxyphosphate formed the digital image analyzing system Quantimet 500+ was used. Estimated values of optical densities of Ce(IV)perhydroxyphosphate over test areas were employed for calculation of kinetic parameters of (G6Pase). Highest activities of G6Pase (higher Km and Vmax levels) were found in periportal areas of the rat liver, indicating a higher amount of active enzyme molecules and a lower affinity for the substrate. Differences in values for both Km and Vmax between periportal and pericentral zones were highly significant and closely comparable to those for male fed rats. Correlations between Km and Vmax were significant for periportal as well for pericentral liver areas. The results of the present study thus allow the same biological implications as histochemical methods employing a final reaction for quantification of enzyme activities. The present method avoids the drawbacks of enhancement reactions and demonstrates the feasibility of in situ analysis of enzyme kinetic parameters by quantification of oxidized primary cerium reaction products.


Asunto(s)
Cerio , Glucosa-6-Fosfatasa/análisis , Histocitoquímica/métodos , Hígado/enzimología , Animales , Técnicas In Vitro , Masculino , Ratas , Ratas Wistar , Procesamiento de Señales Asistido por Computador , Factores de Tiempo
8.
Cell Mol Biol (Noisy-le-grand) ; 40(8): 1113-24, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7873983

RESUMEN

Dysmorphic erythrocyte malformation in urine is characteristic of glomerulonephritis. The mechanisms leading to this phenomenon are still unknown. To obtain evidence of the site as well as of the process of erythrocyte damage, electron microscopical and histochemical investigations of renal biopsy materials from 19 patients with histologically defined glomerulonephritis were performed. The results suggest that the initial damage of erythrocytes in the glomerular area is reasoned by enzymatic glycocalyx destruction. On passage through the tubular system the osmotically sensitized surface altered cells undergo rapid hemolysis and losses of membrane skeletal proteins leading to dysmorphic shape transformations.


Asunto(s)
Eritrocitos Anormales/patología , Glomerulonefritis/sangre , Adulto , Biopsia , Creatinina/orina , Densitometría , Membrana Eritrocítica/fisiología , Eritrocitos , Eritrocitos Anormales/química , Femenino , Glomerulonefritis/patología , Hemoglobinuria/patología , Histocitoquímica , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Microscopía Electrónica , Persona de Mediana Edad , Proteinuria/patología , Receptores de IgG/análisis
9.
Cell Mol Biol (Noisy-le-grand) ; 40(8): 1125-33, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7873984

RESUMEN

In the present study influences leading to in vitro formation of dysmorphic erythrocytes were studied. Fresh and surface altered erythrocytes pretreated with several proteases were passed through different solutions representing distinct nephronís fluids. After passage of intact erythrocytes only 12-15% dysmorphic cells were observed. In case of protease treated cells the number of dysmorphic cells rose to 35-80%. The hemoglobin content was decreased. PAGE and electron microscopical findings demonstrated substantial losses of transmembrane and membrane skeleton proteins. It is assumed that surface protein degradation, loss of membrane skeleton proteins and hemolysis seem to be closely associated with dysmorphic malformation of urinary erythrocytes characteristical for glomerulonephritis.


Asunto(s)
Eritrocitos Anormales , Eritrocitos/patología , Glomerulonefritis/sangre , Anisotropía , Membrana Celular/ultraestructura , Células Cultivadas , Electroforesis en Gel de Poliacrilamida , Glomerulonefritis/patología , Hemólisis/fisiología , Humanos , Túbulos Renales Distales/patología , Glicoproteínas de Membrana/análisis , Proteínas de la Membrana/fisiología
10.
Zentralbl Hyg Umweltmed ; 192(5): 462-72, 1992 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-1554405

RESUMEN

The article deals with interactions between bio-vitro-materials and bacteria species in vitro. The growth of S. aureus, Sc. salivarius, E. coli and Ps. aeruginosa in a salt solution with and without addition of biomaterials was examined until the day 60 in a static culture. By counting the cfu/ml and determination the relative change of germ capacity the results were compared. The data of such series obtained with working materials of similar chemical composition were collected and evaluated. We found, that Ps. aeruginosa was promoted in growth by all materials, especially those, which contained carbon. The same can be said about the last materials and E. coli. In contrast as well Ca- and P-containing as--free biomaterials reduced the numbers of germs. Changes of multiplying of S. aureus and Sc. salivarius seldom were observed. It ist apparent, that the biomaterials tested are not indifferent against a few germs, which may cause infections, but they promote the growth of a few species in vitro. This may favour an infection, if such materials should be implanted. It is proposed to test biomaterials microbiologically before clinical application. Materials with indifferent behavior or low anti-microbiological effect have to be favoured.


Asunto(s)
Bacterias Aerobias/efectos de los fármacos , Materiales Biocompatibles/farmacología , Bacterias Aerobias/crecimiento & desarrollo , Carbono/farmacología , Cerámica/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Politetrafluoroetileno/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Silicio/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Streptococcus/efectos de los fármacos , Streptococcus/crecimiento & desarrollo , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/crecimiento & desarrollo
11.
Artículo en Alemán | MEDLINE | ID: mdl-1420661

RESUMEN

Using microbiologically experimental methods and observations corresponding to praxis the efficiency of the addition of antiseptics to alginate is evaluated. The addition of chlorhexidine to the alginate leads to a considerable reduction of the amounts of germs, but an one hundred percent disinfection of the alginates is not always performed. An influence of the alginate materials and the water quality on the antimicrobial efficacy of chlorhexidine has been proved. The always occurring contamination of the impression tray rules out a complete stopping of infection between the patient and the laboratory staff.


Asunto(s)
Alginatos/farmacología , Desinfección/métodos , Boca/microbiología , Bacterias/efectos de los fármacos , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Técnica de Impresión Dental/instrumentación , Contaminación de Equipos , Humanos , Técnicas In Vitro , Polvos , Saliva/microbiología
12.
Acta Histochem ; 90(2): 127-34, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1927210

RESUMEN

Intact native red blood cells (RBC) and treated RBC preparations were labelled with MC 540 and irradiated in the presence of diaminobenzidine (DAB). The polymerized diaminobenzidine reaction product is permanently stable in comparison with the labile fluorescence labelling. The brownish stained DAB polymerization product (DAB brown) and osmium black (after conversion of DAB brown with OsO4) allow the densitometrical determination with the light microscope. The latter product can be directly observed in the electron microscope. A direct correlation exists between the fluorescence intensity and the polymerized diaminobenzidine staining. It can be deduced that the enhancement of the DAB mediated contrast is reflecting an increased fluidity of the red cell membrane. The reaction was successful with all red cell preparations tested. This method is also suitable for the determination of fluidity changes in other cell membranes.


Asunto(s)
Membrana Eritrocítica/química , Fluidez de la Membrana , Pirimidinonas/química , p-Dimetilaminoazobenceno/química , Diamida/farmacología , Membrana Eritrocítica/efectos de los fármacos , Fluorescencia , Humanos , Técnicas In Vitro , Fluidez de la Membrana/efectos de los fármacos , Microscopía Electrónica , Oxidación-Reducción , Fenilhidrazinas/farmacología , Fotoquímica , Análisis de Regresión
13.
Artículo en Alemán | MEDLINE | ID: mdl-1873404

RESUMEN

The elastic properties of commercial alginate impression materials are not essentially influenced by chlorhexidin at microbiologically effective concentration. The torsion test proved to be a simple reliable method.


Asunto(s)
Alginatos/química , Clorhexidina/química , Técnica de Impresión Dental , Combinación de Medicamentos , Ensayo de Materiales , Estrés Mecánico
14.
Dtsch Stomatol (1990) ; 40(11): 462-3, 1990 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-2133200

RESUMEN

The results suggest a relatively favourable relation between minimum bactericidal concentration (enterococci) and toxic agent concentration (chicken embryos) of hydrogen peroxide in comparison with chlorhexidin-digluconate, sodium-tosylchloramide and peracetic acid. For chlorhexidin-digluconate a somewhat more favourable relation between minimum bacteriostatic and toxic concentration of the agent was established.


Asunto(s)
Antiinfecciosos Locales/farmacología , Enterococcus/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Animales , Antiinfecciosos Locales/toxicidad , Embrión de Pollo , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Clorhexidina/toxicidad , Peróxido de Hidrógeno/toxicidad , Ácido Peracético/farmacología , Ácido Peracético/toxicidad , Compuestos de Tosilo/farmacología , Compuestos de Tosilo/toxicidad
20.
Cell Mol Biol ; 36(6): 643-57, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2083419

RESUMEN

The value of membrane anisotropy after fixation and topo-optical analysis of erythrocytes stained with toluidine blue is a measure for the degree of spatial order of the dyestuff-binding acidic residues of the glycocalyx and thus a parameter for the characterization of the glycocalyx structure. Lowering the pH value and/or the ionic strength of the staining medium results in a decrease of membrane anisotropy indicating a lower order of the anionic residues. In agreement with the findings of other authors this phenomenon seems to be connected with an expansion of the glycocalyx. Diamide-induced oxidative crosslinking of spectrin before fixation and staining with toluidine blue at physiological pH and ionic strength also results in a decreased anisotropy. This indirect influence on the glycocalyx structure may be caused by an increase of the charge density within the glycocalyx due to a diamide-induced rearrangement of the membrane skeleton and of the transmembrane proteins bound to it.


Asunto(s)
Eritrocitos/química , Glicoproteínas/análisis , Polisacáridos/análisis , Espectrina/química , Diamida , Polarización de Fluorescencia , Glicoproteínas/química , Humanos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Polisacáridos/química , Ácidos Siálicos/análisis , Cloruro de Tolonio
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