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31.
Maria Severin Bernd Kirchhof 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1990,228(1):101-104
Three keratoplasties were carried out on two patients because of nodular degeneration of the cornea. Progress after keratoplasty
could be followed up in one eye for 17 months and in the other two eyes, for 2.5 and 9 years, respectively. The implant with
the short follow-up of only 17 months remained glass-clear; nothing abnormal was discovered during the checkups. In the case
of the other patient in whom a longer follow-up period was possible, the following findings were evident: (1) a remarkably
late epithelial immune response in one eye (after 18 months) with subsequent incomplete reepithelisation and formation of
fine, superficial, cloudy opacity (observation period 2.5 years); (2) formation of dense but flat, superficial areas of opacity
in the cornea of the other eye (observation period 9 years). These areas may be regarded as a precursor of Salzmann’s corneal
degeneration. No difference could be found between the histological findings in the explants and those in a degenerative pannus
or an older scar caused by inflammation of the Bowman membrane. 相似文献
32.
P Bernd 《Brain research》1987,430(1):31-38
It has been shown previously that a subpopulation of long-term (7-14 days) cultured neural crest cells undergoing differentiation possesses receptors for nerve growth factor (NGF). These cells are likely to be targets of NGF during the early stages of embryonic development. This study was conducted to determine whether cells exhibiting neuron-like characteristics (i.e. process formation, presence of putative neurotransmitters) in neural crest cultures have NGF receptors. This was accomplished by combining 125I-NGF radioautography and immunocytochemistry using antibodies against tyrosine hydroxylase, serotonin, and vasoactive intestinal polypeptide. Examination of light microscopic radioautographs revealed that none of the neuron-like cells with tyrosine hydroxylase-like, serotonin-like, or vasoactive intestinal polypeptide-like immunoreactivity bound 125I-NGF, and, therefore, do not possess NGF receptors. It is not known whether the lack of NGF receptors on neuron-like cells is due to the early developmental stage of these cells, or is caused by a difference in the microenvironment in vitro as compared to in vivo. The identity of the cultured neural crest cells which do possess NGF receptors remains to be determined. 相似文献
33.
Summary A single glass micropipette voltage clamp technique with intracellular dialysis was used to study the effects of the trapidil derivatives AR 12–456 and AR 12–463 on Ca channel currents carried by Bat+ in isolated ventricular cells from mice hearts. Inspite of a more potent inhibition of the cAMP phosphodiesterase from heart (Bartel et al. 1985) a reversible Ca channel blocking action of both compounds could be observed. The concentration of half maximal block was calculated to about 50 mol/l for both derivatives tested. Neither a shift in the current-voltage relationships nor a significant change in the potential for half maximal activation was found. The maximal Ba2+ -conductance was reduced. The steady state inactivation was shifted towards more negative potentials by application of 100 mol/l AR 12–463. The decay of the Ba currents was accelerated in the range of the applied test potentials between –20 and +20 mV. It is concluded that the new trapidil derivatives with more potent inhibitory action on cardiac phosphodiesterase than trapidil can block myocardial Ca channels.
Send offprint requests to B. Nilius 相似文献
34.
CGP 6809 — A new nitrosoureido-sugar derivative with activity in human tumor xenografts 总被引:1,自引:0,他引:1
Heinz H. Fiebig Karl H. Widmer Bernd R. Winterhalter Georg W. Löhr 《Cancer chemotherapy and pharmacology》1989,23(6):337-340
Summary CGP 6809 [ethyl-6-deoxy-3,5-di-O-methyl-6-(3-methyl-3-nitrosoureido)--d-glucofuranoside] is a new methylnitrosoureido-sugar derivative that has been shown to be active against a broad spectrum of transplantable tumours in mice and rats [14]. We investigated the anti-tumour effect of CGP 6809 in ten selected, human tumour xenograft lines growing s. c. in nude mice. The p. o. administration of 125 mg/kg per day for 10–15 days was less toxic (lethality 12% in tumour-bearing nude mice) than the i. p. injection of 62.5 mg/kg per day (lethality 22%). The anti-tumour effect was similar for both application routes; two large bowel cancers responded to treatment with CGP 6809, rectal cancer CXF 158 showed a remission, and the rapidly growing, undifferentiated colonic cancer CXF 280 exhibited a transient no-change. Furthermore, remissions were observed in the epidermoid lung cancer LXF 322 and in thyroid cancer 117. Tumour progression was found in another epidermoid lung cancer and in three stomach cancers, one melanoma, and one soft tissure sarcoma. CGP 6809 is a promising new agent for clinical trials, especially for large bowel and epidermoid lung cancer.Supported in part by grant PTB 8467 from the Bundesminister für Forschung und Technologie, Bonn, FRG 相似文献
35.
Heppelmann B McDougall JJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,167(1):114-118
Synovial joints are complex sensory organs which provide continuous feedback regarding position sense and degree of limb movement.
The transduction mechanisms which convert mechanical forces acting on the joint into an electrochemical signal which can then
be transmitted to the central nervous system are not well understood. The present investigation examined the effect of the
mechanogated ion channel blockers amiloride and gadolinium on knee joint mechanosensitivity. In deeply anaesthetised rats
(sodium thiopental: 100–120 mg/kg, i.p.), single unit extracellular recordings were made from knee joint group III (Aδ) and
group IV (C) primary afferents in response to mechanical rotation of the joint. Afferent firing rate was measured before and
after topical application of either amiloride (0.1 mM, 1 mM) or gadolinium (250 μM) onto the receptive field of the sensory
unit and recording was continued every 10 min up to a total of 50 min. With normal rotation of the knee, joint mechanosensitivity
was significantly reduced by both amiloride (P<0.0001; n=10–21) and gadolinium (P=0.001; n=12) and this effect was sustained throughout the recording period. This investigation provides the first in vivo electrophysiological
evidence that joint mechanotransduction involves the activation of amiloride and gadolinium-sensitive mechanogated ion channels.
Future studies to determine the mechanogated ion channel subtypes present in joints and the modulation of their gating properties
during inflammation may yield novel approaches for the control of arthritis pain.
Funding: JJMcD is funded by the Alberta Heritage Foundation for Medical Research, the Canadian Institutes for Health Research, and
the Arthritis Society of Canada. 相似文献
36.
Jahrsdörfer B Wooldridge JE Blackwell SE Taylor CM Griffith TS Link BK Weiner GJ 《Journal of leukocyte biology》2005,77(3):378-387
Immunostimulatory oligodeoxynucleotides (IS ODN) can mediate a number of immunologic effects. We previously demonstrated that treatment of B cell chronic lymphocytic leukemia (B-CLL) cells with one class of IS ODN, CpG ODN, alters their phenotype and increases their immunogenicity. Here, we demonstrate that in contrast to the classic understanding of CpG ODN as inhibitors of B cell apoptosis, IS ODN including CpG ODN induce apoptosis in B-CLL cells. It is important that these changes are seen not only with CpG ODN but with ODN that lack the classical CpG motif. B-CLL cells from 20 subjects were treated in vitro with IS ODN for up to 7 days. IS ODN treatment resulted in increased numbers of apoptotic cells in 13 out of 20 B-CLL samples. IS ODN enhanced apoptosis in samples with 13q deletion as a single aberration and had a heterogeneous effect on apoptosis in samples with other aberrations including 17p deletion, 11q deletion, or trisomy 12. Induction of apoptosis did not correlate with expression of the CpG ODN receptor Toll-like receptor 9. Apoptosis was dependent on the activation of caspases and was accompanied by up-regulation of CD95/Fas and its ligand. We conclude that IS ODN including CpG ODN can induce apoptosis of most B-CLL samples. The ability of IS ODN to induce apoptosis differs based on cytogenetic status. Up-regulation of CD95/Fas may play a role in IS ODN-induced apoptosis of B-CLL. 相似文献
37.
Transient receptor potential (TRP) channels provide an enormous variability of Ca(2+) influx mechanisms triggered by a wide range of stimuli. In this review, we discuss the activation properties of the Ca(2+)- and Mg(2+)-permeable TRP channel of the vanilloid subfamily TRPV4. This channel is activated by various physical and chemical stimuli, such as cell swelling, heat, phorbols and, probably, by endogenous ligands, which are able to induce Ca(2+) entry. Not much is known about the regulation of this channel. We will refer only to a mechanism of Ca(2+)-dependent inhibition of TRPV4. Possible functional roles of this channel will be correlated with its observed expression pattern. Finally, we discuss the structural determinants of TRPV4 channel function. 相似文献
38.
Macrophage response to peripheral nerve injury: the quantitative contribution of resident and hematogenous macrophages 总被引:6,自引:0,他引:6
Mueller M Leonhard C Wacker K Ringelstein EB Okabe M Hickey WF Kiefer R 《Laboratory investigation; a journal of technical methods and pathology》2003,83(2):175-185
Whereas local microglial cells of the CNS rapidly respond to injury, little is known about the functional role of resident macrophages of the peripheral nervous system in nerve pathology. Using bone marrow chimeric rats, we recently identified individual resident endoneurial macrophages that rapidly became activated after nerve injury. However, the extent of local macrophage activation and its quantitative contribution to the total macrophage response is unknown. We now have created chimeric mice by transplanting bone marrow from green fluorescent protein (GFP)-transgenic mice into irradiated wild-type mice, allowing easy differentiation and quantification of hematogenous and resident endoneurial macrophages. After sciatic nerve crush injury, both GFP(-) and GFP(+) resident macrophages, the latter having undergone physiological turnover from the blood before injury, rapidly underwent morphological alterations and increased in number. Proliferating GFP(-) and GFP(+) resident macrophages were abundant and peaked 3 days after injury. A major lesion-induced influx of hematogenous macrophages with a disproportionate increase of GFP(+) macrophages was not observed until Day 4. Throughout all time points examined, GFP(-) resident macrophages were strikingly frequent, reaching maximum numbers 9.5-fold above baseline. There was also a notable proportion of GFP(-) resident endoneurial macrophages phagocytosing myelin and expressing major histocompatibility complex class II. Our results demonstrate for the first time that the rapid response of resident endoneurial macrophages to nerve injury is quantitatively important and that local macrophages contribute significantly to the total endoneurial macrophage pool during Wallerian degeneration. 相似文献
39.
Zipfel S Schneider A Wild B Löwe B Jünger J Haass M Sack FU Bergmann G Herzog W 《Psychosomatic medicine》2002,64(5):740-747
OBJECTIVE: This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated. METHOD: An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome. RESULTS: Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables. CONCLUSIONS: Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated. 相似文献
40.
Zusammenfassung Aus eigener Zucht stammende Larven, Nymphen und Imagines von Amblyomma testudinis wurden auf ihre Sinnesleistungen hinsichtlich Phototaxis, Thermotaxis, Geotaxis und Chemotaxis untersucht. Es ergab sich ein entwicklungsabhängiger Wandel im phototaktischen Verhalten von anfangs positiver Phototaxis bei den Larven über indifferente Phototaxis bei vollgesogenen Larven und nüchternen Nymphen zu negativer Phototaxis bei vollgesogenen Nympen sowie - und -Imagines. Sämtliche Entwicklungsstadien mit Ausnahme der -Imagines verhalten sich temperaturindifferent vor dem Kontakt mit einem Wirt; vollgesogene Larven und Nymphen dagegen bevorzugen niedrige Temperaturen. Nymphen und Imagines, die noch nicht gesogen haben, reagieren negativ geotaktisch. Sie erklettern vermutlich in der Natur die Spitzen von Pflanzen und Steinen, um dort das Vorbeikriechen eines Wirtes abzuwarten. Imagines von Amblyomma testudinis reagieren mit einer positiven Chemotaxis auf Schlangen stärker als auf Kröten. Auch Substrat aus Schlangenbehältern enthält mindestens für 30 Std nach der Entfernung der Schlangen chemotaktisch wirksame Stoffe.
Contributions to sensory physiology of the tick Amblyomma testudinis
Summary Phototaxis, thermotaxis, geotaxis and chemotaxis of larvae, nymphs and adults of Amblyomma testudinis from own breedings were studied. The phototactic behaviour changed according to the different stages of development: unfed larvae were positively phototactic, fed larvae and unfed nymphs were indifferent, fed nymphs but also the adults showed a negative phototaxis.—All stages of development besides the females reacted without any preference for a distinct temperature, whereas larvae and nymphs after feeding prefered lower temperatures.—Unfed nymphs and adults were negatively geotactic which corresponds to their natural behaviour of climbing plants for catching hosts.—Adults of Amblyomma testudinis showed a higher rate of chemotaxis for snakes than for toads; substrate from snake cages containes chemotaxis inducing substances for more than 30 hours after elimination of the snakes.相似文献