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  • 1
    Electronic Resource
    Electronic Resource
    Tracer permeability of rat cortical blood vessels during regional hypothermia (1987)
    Springer
    Acta neuropathologica 73 (1987), S. 349-356 
    Details
    ISSN: 1432-0533
    Keywords: Blood-brain barrier ; Cortex ; Lanthanum tracer ; Potassium ; Ion-selective micro-electrode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Using lanthanum nitrate as a tracer, the permeability of rat cortical blood vessels was investigated during regional hypothermia of the cerebral cortex by electron microscopy. The concentration of K+ ions in the extracellular space of the cortex was determined using an ion-selective micro-electrode. Only at temperatures below about 7°C was an extravasation of tracer observed in a number of cortical capillaries and arterioles, where some of the tight junctions became widened and permeable. In a few cases penetration of the tracer into vacuoles of phagocytosing pericytes or macrophages was found. The extravasation of the tracer could mainly be observed in vessels on and below the cortical surface, less often in deeper cortical parts. At the same degree of hypothermia, the K+ concentration in the extracellular space increased, reaching a maximal value of ca. 6 mmol/l at a depth of about 200 μm. As could be shown in one previous experiment, the K+ concentration reached normal values again after rewarming to 37°C for 15 min, but an extravasation of the tracer was still observed. The role of the endothelial tight junctions and of the astrocytes together with the pericytes (or macrophages) is discussed regarding their importance for the effectiveness of the blood-brain barrier system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688258
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  • 2
    Electronic Resource
    Electronic Resource
    The Gap Junctional Protein Connexin(Cx)43 in Testicular Cancer: its Loss Marks Progession from Carcinoma In Situ to Invasive Germ Cell Tumour (2005)
    Berlin, Germany : Blackwell Verlag GmbH
    Anatomia, histologia, embryologia 34 (2005), S. 0 
    Details
    ISSN: 1439-0264
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Carcinoma-in-situ (CIS) of the testis is known to be the pre-invasive stage of most human germ cell tumours (seminoma and non-seminoma), but the mechanisms leading to an increased pubertal proliferation of CIS cells after a long latency and to progression of CIS to an invasive malignancy are still not known. Additionally, CIS and seminoma have also been reported in equine testis (Veeramachaneni and Sawyer, 1998). The gap junctional protein and tumour suppressor gene connexin(cx)43 represents the predominant cx in human, canine and rodent testis so far and it is expected to play a key role for the regulation of both proliferation and differentiation of germ cells (spermatogonia and spermatocytes), and its gene- and protein-expression pattern is typical for the pubertal terminal differentiation of somatic Sertoli cells. Using cDNA-microarray analysis, in-situ hybridization (ISH), RT-PCR from tissue homogenate and semi-quantitative RT-PCR from well defined microdissected tubules with normal spermatogenesis, CIS, intratubular seminoma (ISe) and from seminoma cells from invasive seminoma we found a downregulation of cx43 starting in intratubular CIS, leading to a complete loss in most invasive seminoma cells. This indicates that regulation of cx43 expression takes place at transcriptional level confirming and expanding earlier studies of protein expression (Brehm et al., 2002). This reduction of cx43-expression suggests that an early intratubular derangement in cx43-gene expression and disruption of inter-cellular communication between Sertoli cells and/or Sertoli cells and pre-invasive tumour cells via cx43-gap junctions may play a role in the proliferation of CIS cells and seminoma cells and in the progression phase of testicular seminoma development.References  Veeramachaneni, D. N., and H. R.Sawyer, 1998: Carcinoma in situ and seminoma in equine testis. APMIS 106, 183–185.Brehm R., A. Marks, R. Rey, S. Kliesch, M. Bergmann and K. Steger, 2002: Altered expression of connexins 26 and 43 in Sertoli cells in seminiferous tubules infiltrated with carcinoma-in-situ or seminoma. J. Pathol. 197, 647–653.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1439-0264.2005.00669_16.x
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  • 3
    Electronic Resource
    Electronic Resource
    The Expression of Connexins during Growth and Development of Skeletal Elements in the Dog (2005)
    Berlin, Germany : Blackwell Verlag GmbH
    Anatomia, histologia, embryologia 34 (2005), S. 0 
    Details
    ISSN: 1439-0264
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Efficient and well-regulated intercellular communication is essential to organize the activities of the different cell populations involved during growth and concomitant structural maturation of the skeleton. For direct cell-cell communication gap junctions composed of connexins (Cx) are present. So far 21 Cx types have been identified in mammals, which differ in molecular permeability as well as tissue expression pattern. To characterize the Cx distribution in the developing canine skeleton, samples from humerus, scapula and lumbar vertebrae of Beagle dogs aged 1.5, 3, 4.5 months and 1.5 years were fixed in Bouin's solution, decalcified with 25% EDTA and embedded in paraffin wax. Using immunohistochemistry and in situ hybridization, the expression of Cx 26, 30, 31, 32, 43, and 45 was studied in bone tissue plus associated epiphyseal and growth plate cartilage. Of all bone cells, osteoblasts showed the largest Cx expression repertoire: they were positive for Cx 26, 30, 32 and 43. After transformation into bone lining cells Cx43 expression was lost while in osteocytes only Cx 26 and 32 was detected. A wide variety of Cx reactions was also found in osteoclasts: Cx 26, 30, 32, and 43. In contrast, chondrocytes showed a much more restricted Cx expression pattern. Positive reactions were only seen in hypertrophic chondrocytes of epiphyseal cartilage (Cx 26, 31, 32) and in the proliferative (Cx32) and hypertrophic zone (Cx 26 and 32) of growth plate cartilage. Additionally, Cx31 was strongly expressed in the cellular layer of the periosteum covering areas of intensive bone modelling in the puppies. Age- and microlocation-dependent variations in expression and/or staining intensity were also observed in the other Cx types. These results demonstrated that canine bone cells are capable of synthesizing a wide variety of Cx types during skeletal development, thus propagating different cellular signals via gap junctions in a differentially regulated and requirement orientated manner.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1439-0264.2005.00669_106.x
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  • 4
    Electronic Resource
    Electronic Resource
    Ultrastructural Evidence for Transport of Protein across the Epithelium of the Rat Caput Epididymidis (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 513 (1987), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1987.tb25099.x
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  • 5
    Electronic Resource
    Electronic Resource
    The cruciate ligaments in knee replacement (1989)
    Springer
    International orthopaedics 13 (1989), S. 13-16 
    Details
    ISSN: 1432-5195
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les ligaments croisés du genou ont été réséqués avec leurs insertions osseuses au cours d'arthroplasties totales du genou réalisées sur douze sujets atteints de graves lésions d'arthrose ou de polyarthrite rhumatoïde. Les ligaments ont été étudiés sur le plan histologique et biomécanique, et dix spécimens provenant d'adultes sains ont été utilisés comme contrôle. On a mis en évidence des différences significatives de la résistance et des propriétés visco-élastiques des ligaments entre ceux des patients arthrosiques et les autres. Les ligaments des genoux rhumatoïdes présentaient une résistance nettement plus faible comparativement à ceux des genoux arthrosiques. L'arthroplastie totale du genou qui remplace également la fonction ligamentaire, peut donc être efficace dans les genoux rhumatoïdes, grandement endommagés.
    Notes: Summary The cruciate ligaments were resected with their bony insertions during total knee arthroplasty carried out in 12 patients with severe rheumatoid or osteoarthritis. The ligaments were examined histologically and biomechanically, using ten specimens from healthy adults as a control. A significant difference was found in the tensile stiffness and viscoelastic properties of the ligaments between the arthritic and the control group. The ligaments in the rheumatoid knees had a distinctly inferior tensile strength compared with the osteoarthritic knees. Total knee replacement, which also replaces ligament function, should therefore be considered in severely damaged rheumatoid knees.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00266716
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  • 6
    Electronic Resource
    Electronic Resource
    Use of fosfomycin disks for isolation of diphtheroids (1988)
    Springer
    European journal of clinical microbiology & infectious diseases 7 (1988), S. 190-193 
    Details
    ISSN: 1435-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A fosfomycin disk (200 µg) placed on blood agar was used to select diphtheroids from clinical specimens. AllCorynebacterium type strains tested, representing ten different groups of diphtheroids, and 150 toxigenic strains ofCorynebacterium diphtheriae from different outbreaks, overgrew the fosfomycin disk, while other aerobic gram-positive rods had a large inhibition zone. The method increased the rate of isolation of diphtheroids in 1267 clinical specimens fivefold, from 1.4 % to 7.6 %, especially when the diphtheroids were found concomitantly with other bacteria. Overgrowth of the disk by other microorganisms occurred in 11 % of the samples tested, but such microorganisms could easily be distinguished by culture morphology or Gram stain. Fosfomycin disks provide a simple, highly sensitive but not very specific aid for isolation ofCorynebacterium diphtheriae and diphtheroids from clinical specimens.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01963079
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  • 7
    Electronic Resource
    Electronic Resource
    Fraction of H-bonded segments of N-ethylpyrrolidone, oligomeric and polymeric vinylpyrrolidone adsorbed from CHCl3 on silica measured by IR spectrometry (1985)
    Springer
    Colloid & polymer science 263 (1985), S. 372-380 
    Details
    ISSN: 1435-1536
    Keywords: Polymer adsorption ; IR spectrometry ; fraction of adhered segments ; silica
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The adsorption of N-ethylpyrrolidone (NEP), oligomeric and polymeric vinylpyrrolidone (OVP, PVP) on silica (Aerosil 200) from CHCl3 solution is investigated by IR spectrometry. The influence of the annealing temperature of the silica on the adsorbed amount and on the fraction of adhered segments was studied. The dependences of the amount adsorbed on solution concentration result for NEP in a Langmuir isotherm for OVP and PVP in high affinity isotherms. The fraction of adhered H-bridged carbonyl groups determined by compensation procedures, the fraction of surface SiOH groups occupied and the multiple interaction quotientQ show different dependences on the amount adsorbed for the measured adsorptives, indicating different interactions of the monomeric segments with the surface groups. This behaviour is explained by comparing the amount adsorbed in saturation with monolayer capacities, surface concentration of SiOH groups and frequency shifts. A splitting of the band of the bound carbonyl groups in a double peak was observed with OVP and PVP, referring to an additional interaction of polymer segments neighboured to specifically bound segments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410383
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  • 8
    Electronic Resource
    Electronic Resource
    Microcalorimetric studies of the adsorption of N-ethylpyrrolidone, oligomeric and polymeric vinylpyrrolidone from CHCl3 on silica (1985)
    Springer
    Colloid & polymer science 263 (1985), S. 381-387 
    Details
    ISSN: 1435-1536
    Keywords: polymer adsorption ; microcalorimetry ; enthalpy of adsorption ; fraction of adhered segments ; silica
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Adsorption enthalpies of N-ethylpyrrolidone, oligomeric and polymeric vinylpyrrolidone from CHCl3 solution on silica interfaces (Aerosil 200) have been measured at 25 °C by microcalorimetry. The dependence on surface coverage has been examined using measured adsorption isotherms. Binding enthalpies are calculated with fractions of adhered segments obtained by IR spectrometry and wetting enthalpies received from calorimetry. Fractions of adhered segments are derived from the adsorption enthalpies assuming equal binding enthalpies of monomers and polymer segments and considering desorption enthalpies of the solvent depending on the surface area of the polymer segments. The resulting enthalpies are compared with literature values from other solvents and the incongruity of the fraction of adhered segments obtained by IR, ESR, NMR and microcalorimetry is explained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410384
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  • 9
    Electronic Resource
    Electronic Resource
    Ultrastructural localization of thyrotropin (TSH)-like immunoreactivity in specific secretory cells of the hypophyseal pars tuberalis in the Djungarian hamster, Phodopus sungorus (1989)
    Springer
    Cell & tissue research 256 (1989), S. 649-652 
    Details
    ISSN: 1432-0878
    Keywords: Hypophyseal pars tuberalis ; (TSH), Thyrotropin ; Immunocytochemistry ; Photoperiod ; Phodopus sungorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Specific secretory cells in the hypophyseal pars tuberalis of Djungarian hamsters maintained under different photoperiods were investigated immunocytochemically by means of the colloidal gold technique using antibodies against rat thyrotropin (TSH). Secretory cells of animals kept under long photoperiods (LD16:8) showed positive staining of secretory granules (diameters 90–130 nm), whereas other intracellular structures were free of immunoreactivity. In animals kept under short photoperiods (LD8:16) secretory cells displayed increased numbers of secretory granules, but these organelles were devoid of immunoreactivity. In contrast, immunoreactivity of thyrotropes in the pars distalis did not differ between the two groups of animals investigated. The present results confirm earlier light-microscopical studies that in the pars tuberalis specific secretory cells show TSH-like immunoreactivity; however, they differ in their reactivity pattern from classical thyrotropes in the pars distalis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225616
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  • 10
    Electronic Resource
    Electronic Resource
    Transcytosis in the epididymis studied by local arterial perfusion (1988)
    Springer
    Cell & tissue research 253 (1988), S. 631-637 
    Details
    ISSN: 1432-0878
    Keywords: Epididymal ultrastructure ; Transcytosis ; Protein transport ; Fluid-phase endocytosis ; Epididymal arterial perfusion ; Rat (Sprague-Dawley) ; Golden hamster ; Mouse (CB6/F1)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The transport of protein across the cells of the epididymal epithelium was studied using horseradish peroxidase. Transient vascular perfusion of the epididymis of the rat and golden hamster was achieved by pulsatile retrograde infusion into the testicular artery. Peroxidase was found in the interstitium and in the epithelium, located in vesicles, vacuoles and multivesicular bodies of principal, clear and apical cells. Similar findings were obtained in mice after systemic injection of the tracer. In the rat, discharge to the lumen was confirmed by the appearance of enzyme activity in luminal fluid from the caput epididymidis after local injection. The extent of transport amounted to no more than what has been considered leakage in physiological experiments, and the time-course of appearance complemented that found by electron microscopy. The level of transcytosis after pulsatile administration of peroxidase in vivo, as judged from the occurrence of tracer in the epithelium, was much less than that obtained during constant immersion in vitro. The protein was present in multivesicular bodies of principal cells and in vesicles of clear cells at short times after presentation in vitro, when it could not have arrived by endocytosis from the lumen. This suggests that routing of basal endocytic vesicles to the lysosomal apparatus occurs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219754
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