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41.
Retinoids induce Fas(CD95) ligand cell surface expression via RARgamma and nur77 in T cells 总被引:2,自引:0,他引:2
Tóth B Ludányi K Kiss I Reichert U Michel S Fésüs L Szondy Z 《European journal of immunology》2004,34(3):827-836
Cells from the CD4+ murine T hybridoma line IP-12-7 enter the apoptotic suicide program via the Fas ligand (FasL)/Fas-mediated pathway upon TCR stimulation. This stimulus regulates the sensitization of the Fas death pathway and the cell surface appearance of preformed FasL. The apoptosis is dependent on new mRNA and protein synthesis and involves up-regulation of nur77.Two groups of nuclear receptors for retinoic acids (RA) have been identified: retinoic acid receptors (RAR) and retinoid X receptors. IP-12-7 cells express RARalpha and RARgamma. Here we show that,in the IP-12-7 T cells, RA also induced the expression and DNA binding of nur77, and the cell surface appearance of FasL. The induction was mediated via RARgamma. Despite the induced expression of cell surface FasL, only two structurally related RARgamma-selective compounds, CD437 and CD2325, initiated apoptosis in these cells. The lack of apoptosis induction by natural RA was related to the inability of RARgamma to sensitize the Fas death-pathway. Cell surface FasL, however, was able to induce cell death in Fas-bearing target cells. Natural RA also induced the expression of FasL in phytohemagglutinin-activated peripheral murine T cells. It is proposed that therapeutically administered RA might induce apoptosis in Fas-sensitive cells via induction of FasL expression in activated Tcells. 相似文献
42.
Niedhart C Maus U Piroth W Miltner O Schmidt-Rohlfing B Siebert CH 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,71(1):123-129
The gold standard for bone substitution is the autologous bone graft, but because of its limited supply and the associated morbidity, the search for synthetic alternatives is necessary. A new in situ setting tricalcium phosphate cement was implanted in a trepanation defect (9.4 mm diameter, 10 mm depth) in the distal femoral epiphysis of sheep. Empty cavities and autologous bone graft were used as controls. Histologic and histomorphometric examinations were carried out after 12 weeks. Nearly 90% of the implanted cement was resorbed and replaced by ingrown bone with close contact between surrounding bone, new bone, and remaining cement particles. The amount of bone in the defect area was significantly higher in defects filled with cement relative to defects filled with autologous bone graft (mean 27 vs. 21%, 95% confidence intervals 23 to 31 and 18 to 23, p = 0.026). In conclusion, this new in situ setting cement is bioactive, resorbable, and osteoconductive. It will be useful as an alternative to autologous bone graft to fill stable defects. 相似文献
43.
Iliac and sacral articular cartilage of 25 human sacroiliac joints (1–93 years) are examined by light microscopy and immunohistochemistry
in order to gain further insight into the nature and progress of degenerative changes appearing during aging. These changes
can already be seen in younger adults as compared to cartilage degeneration known in other diarthrodial joints. Structural
differences between sacral and iliac cartilage can already be observed in the infant: the sacral auricular facet is covered
with a hyaline articular cartilage, reaching 4 mm in thickness in the adult and staining intensely blue with alcian blue at
pH1. Iliac cartilage of the newborn is composed of a dense fibrillar network of thick collagen bundles, crossing each other
at approximately right angles. A faint staining with alcian blue suggests a low content of acidic glycosaminoglycans. In the
adult, iliac cartilage becomes hyaline and its maximal thickness reaches 1–2 mm. Both articular facets exhibit morphological
changes during aging that are more pronounced in the iliac cartilage and resemble osteoarthritic degeneration; the staining
pattern of the extracellular matrix becomes inhomogenous, chondrocytes are arranged in clusters and the articular surface
develops superficial irregularities and fissures. Sometimes fibrous tissue fills up these defects. Nevertheless, large areas
of iliac cartilage remain hyaline in nature. Sacral articular cartilage often remains largely unaltered until old age. The
sacral subchondral bone plate is usually thin and shows spongiosa trabeculae inserted at right angles, suggesting a perpendicular
load on the articular facet. Iliac subchondral spongiosa shows no definite alignment and joins the thickened subchondral bone
plate in an oblique direction. The iliac cartilage therefore seems to be stressed predominantly by shearing forces, arising
from the changing monopodal support of the pelvis during locomotion. The subchondral bone plate on both the iliac and sacral
auricular facet is penetrated by blood vessels that come into close contact with the overlying articular cartilage. These
vessels may contribute to the high incidence of rheumatoid and inflammatory diseases in the human sacroiliac joint. Immunolabelling
with an antibody against type II collagen reveals a diminished immunoreactivity in the upper half of adult sacral cartilage
and only a faint and irregular labelling in the iliac cartilage. Type I collagen can be detected in a superficial layer on
the sacral articular surface and around chondrocyte clusters in iliac cartilage, as in dedifferentiating chondrocytes during
the development of osteoarthritis.
Accepted: 22 April 1998 相似文献
44.
Uwe Beginn Gabriela Zipp Martin Mller Gary Johansson Virgil Percec 《Macromolecular chemistry and physics.》1997,198(9):2839-2852
Crystallization and supramolecular aggregation of 1,4,7,10,13-pentaoxacyclopentadecane-2-ylmethyl 3,4-bis[4-(dodecyl-1-oxy)benzyloxy]-5-(11-methacryloyloxyundecyl-1-oxy)benzoate ( 1 ) and its complexes with sodium triflate are described in solutions of the methacrylate monomers. Formation of a gel was observed covering a rather wide concentration range in the pseudo-binary phase diagram. In the low concentration regime and at low temperatures, gel formation by elongated crystals of 1 was observed. It was demonstrated that the formation of a crystalline network and the shape of the crystals strongly depend on the cooling rate. 相似文献
45.
Expression of Matrix Metalloproteinases and Their Tissue Inhibitors in Human Brain Tumors 总被引:16,自引:0,他引:16 下载免费PDF全文
Klaus Lampert Uwe Machein Mrcia Regina Machein Walter Conca Hans Hartmut Peter Benedikt Volk 《The American journal of pathology》1998,153(2):429-437
In this study, we investigated the expression patterns of 15 matrix metalloproteinases (MMPs) and three tissue inhibitors of metalloproteinase in gliomas, medulloblastomas, and normal brain tissue. By Northern blot analysis we found increased levels of mRNAs encoding for gelatinase A, gelatinase B, two membrane-type MMPs (mt1- and mt2-MMP), and tissue inhibitors of metalloproteinase-1 in glioblastomas and medulloblastomas. We observed a significant increase of mt1-MMP, gelatinase A, gelatinase B, and tissue inhibitors of metalloproteinase-1 in glioblastomas as compared with low-grade astrocytomas, anaplastic astrocytomas, and normal brain. In medulloblastomas, the expression of mt1-MMP, mt2-MMP, and gelatinase A were also increased, but to a lesser extent than that observed in glioblastomas. These data were confirmed at the protein level by immunostaining analysis. Moreover, substrate gel electrophoresis showed that the activated forms of gelatinases A and B were present in glioblastomas and medulloblastomas. These results suggest that increased expression of mt1-MMP/gelatinase A is closely related to the malignant progression observed in gliomas. Furthermore, the present study demonstrates, to our knowledge for the first time, that medulloblastomas express high levels of MMP. 相似文献
46.
47.
Jürgen Dressnandt Uwe Jürgens 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,89(3):549-559
Summary In 11 squirrel monkeys (Saimiri sciureus), the brain stem was systematically explored with electrical brain stimulation for sites affecting the acoustic structure of ongoing vocalization. Vocalization was elicited by electrical stimulation of different brain structures. A severe deterioration of the acoustical structure of vocalization was obtained during stimulation of the caudoventral part of the periaqueductal grey, lateral parabrachial area, corticobulbar tract, nucl. ambiguus and surrounding reticular formation, facial nucleus, hypoglossal nucleus, solitary tract nucleus and along the fibres crossing the midline at the level of the hypoglossal nucleus. It is suggested that these structures are part of, or at least have direct access to, the motor coordination mechanism of phonation. Complete inhibition of phonation was obtained from the raphe and raphe-near reticular formation.Abbreviations Ab
nucl ambiguus
- APt
area praetectalis
- BC
brachium conjunctivum
- BP
brachium pontis
- Cb
cerebellum
- CC
corpus callosum
- Cd
nucl. caudatus
- Cf
nucl. cuneiformis
- Cel
nucl. centralis lateralis
- Cl
claustrum
- CM
centrum medianum
- Cn
nucl. cuneatus
- Co
nucl. cochlearis
- CoI
colliculus inferior
- CoS
colliculus superior
- CP
commissura posterior
- CPf
cortex piriformis
- CRf
corpus restiforme
- CSL
nucl. centralis superior lateralis thalami
- CT
corpus trapezoideum
- DBC
decussatio brachii conjunctivi
- DG
nucl. dorsalis tegmenti (Gudden)
- DLM
decussatio lemnisci medialis
- DPy
decussatio pyramidum
- DR
nucl. dorsalis raphae
- DV
nucl. dorsalis n. vagi
- DIV
decussatio n. trochlearis
- EP
epiphysis
- FC
funiculus cuneatus
- FL
funiculus lateralis
- FLM
fasciculus longitudinalis medialis
- FRM
formatio reticularis myelencephali
- FRP
formatio reticularis pontis
- FRPc
formatio reticularis pontis caudalis
- FRPo
formatio reticularis pontis oralis
- FRTM
formatio reticularis mesencephali
- FV
funiculus ventralis
- G
nucl. gracilis
- GC
substantia grisea centralis (periaqueductal grey)
- GL
nucl. geniculatus lateralis
- GM
nucl. geniculatus medialis
- GP
globus pallidus
- GPM
griseum periventriculare mesencephali
- GPo
griseum pontis
- Hip
hippocampus
- HL
nucl. habenularis lateralis
- H
habenula
- IP
nucl. interpeduncularis
- LC
locus coeruleus
- LD
nucl. lateralis dorsalis thalami
- Lim
nucl. limitans
- LLd
nucl. lemnisci lateralis, pars dorsalis
- LLv
nucl. lemnisci lateralis, pars ventrali
- LM
lemniscus medialis
- LP
nucl. lateralis posterior thalami
- MD
nucl. medialis dorsalis thalami
- MV
nucl. motorius n. trigemini
- NCS
nucl. centralis superior
- NCT
nucl. trapezoidalis
- NMV
nucl. mesencephalicus n. trigemini
- NR
nucl. ruber
- NSV
nucl. spinalisn. trigemini
- NTS
nucl. tractus solitarii
- NIII
nucl. oculomotorius
- NIV
nucl. trochlearis
- NVI
nucl. abducens
- NVII
nucl. facialis
- NXII
nucl. hypoglossus
- OI
oliva inferior
- OS
oliva superior
- P
nucl. posterior thalami
- PbL
nucl. parabrachialis lateralis
- PbM
nucl. parabrachialis medialis
- PC
depedunculus cerebri
- Pd
nucl. peripeduncularis
- Pg
nucl. parabigeminalis
- Pp
nucl. praepositus
- PuI
nucl. pulvinaris inferior
- PuL
nucl. pulvinaris lateralis
- PuM
nucl. pulvinaris medialis
- PuO
nucl. pulvinaris oralis
- Py
tractus pyramidalis
- Pv
nucl. principalis n. trigemini
- R Ab
nucl. retroambiguus
- RL
nucl. reticularis lateralis
- RTP
nucl. reticularis tegmenti pontis
- Sf
nucl. subfascicularis
- SGD
substantia grisea dorsalis
- SGV
substantia grisea ventralis
- SN
substantia nigra
- ST
stria terminalis
- St
subthalamus
- TRM
tractus retroflexus (Meynert)
- TSc
tractus spinocerebellaris
- Ves
nucl. vestibularis
- VL
nucl. ventralis lateralis
- VPI
nucl. ventralis posterior inferior
- VPL
nucl. ventralis posterior lateralis
- VPM
nucl. ventralis posterior medialis
- VR
nucl. ventralis raphae
- Zi
zona incerta
- II
tractus opticus
- VII
n. facialis 相似文献
48.
Brieger P Roettig S Ehrt U Wenzel A Blöink R Marneros A 《Journal of affective disorders》2003,73(1-2):99-104
BACKGROUND: Temperament is an important factor in affective illness. There is some indication that mixed episodes result from an admixture of inverse temperamental factors (e.g. depressive and/or anxious) to a manic syndrome. To test this hypothesis, which has been first formulated by Akiskal [Clin. Neuropharmacol. 15 (Suppl. 1A) (1992) 632-633], we compared the temperament of non-acute bipolar affective patients with and without the history of a previous mixed episode. METHODS: Patients who had been hospitalized for a bipolar disorder were re-assessed at least 6 months after their last in-patient treatment. Those who met the criteria for a partially remitted or full affective or psychotic episode at re-assessment were excluded from the study. Data concerning illness history, current psychopathology (SCID-I interview), depression (BDI), mania (Self-Report Manic Inventory) and temperament (TEMPS-A scale) were obtained. Patients with and without a history of previous mixed episodes were compared. RESULTS: Of 49 eligible former patients, 22 subjects with and 23 subjects without a former mixed episode in bipolar affective disorder fulfilled the inclusion criteria. Subjects suffering from bipolar affective disorder exhibited significantly more depressive and anxious and less hyperthymic temperament, if they had experienced a mixed episode previously. Concerning cyclothymic and irritable temperament, bipolar affective patients with a former mixed episode presented non-significantly higher scores. Patients with a former mixed episode presented with higher depression scores than patients without such a history. No group differences were found concerning current mania scores. LIMITATIONS: (1). This is a preliminary report from an ongoing study. (2). Temperament had not been assessed premorbidly. (3). Although group comparisons revealed significant differences, these did not seem great enough to fully explain the emergence of a mixed episode. CONCLUSION: Our findings support the study's hypothesis that mixed episodes occur more often in subjects with an inverse temperament (e.g. depressive and anxious), although it cannot be ruled out that subsyndromal features of the bipolar illness had an effect on temperament assessment. 相似文献
49.
The trisomy 16 mouse model of Down syndrome has been used to compare calcium (Ca)-homeostasis and Ca-signaling in astrocytes from trisomic mice and from diploid littermates. Ratio calcium-imaging of Fura-2/AM loaded primary astroglial cultures prepared from the hippocampus shows that resting Ca levels are on average significantly higher in trisomic than in the control astrocytes (280 vs. 120 nM). Serotonin (3 μM) and glutamate (30–300 μM) evoked transient Ca-increases from 400 to 600 nM in euploid but from only 20 to 150 nM in trisomic astrocytes. Imaging of ATP-driven Ca-accumulation in cellular organelles revealed a significantly stronger uptake of Ca in trisomic astrocytes that might buffer cytosolic Ca-increases. Our results demonstrate major disturbances in Ca-signaling in trisomic astrocytes that are likely to be of pathophysiological relevance. 相似文献
50.
Claudia Eder Hans -Georg Fischer Ulrich Hadding Uwe Heinemann 《Pflügers Archiv : European journal of physiology》1995,430(4):526-533
Microglia were isolated from a murine neonatal brain cell culture in which their development had been stimulated by supplementation with the macrophage/microglial growth factor macrophage colony-stimulating factor (M-CSF). Using the whole-cell configuration of the patch-clamp technique, voltage-gated membrane currents were recorded from these microglial cells. Hyperpolarization induced inward rectifying K+ currents, as described for microglia from untreated cultures. These currents activated negative to the K+ equilibrium potential and, with a strong hyperpolarization, displayed time-dependent inactivation. The inactivation was abolished when extracellular NaCl was replaced by N-methyl-d-glucamine (NMG), thereby indicating a partial block of this K+ conductance by Na+. Inward rectifying currents were also blocked by extracellularly applied Cs+ or Ba2+. They were slightly diminished following treatment with extracellular tetraethylammonium chloride (TEA) but were not affected by 4-aminopyridine (4-AP). Upon long lasting depolarizing voltage pulses to potentials positive to 0 mV, the cells exhibited a slowly activating H+ current which could be reduced by application of inorganic polyvalent cations (Ba2+, Cd2+, Co2+, La3+, Ni2+, Zn2+) as well as by 4-AP or TEA. Based on their kinetics and pharmacological characteristics, both currents detected on M-CSF-grown microglia are suggested to correspond to the inward rectifier and the H+ current of macrophages. 相似文献