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61.
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
62.
Expression of Matrix Metalloproteinases and Their Tissue Inhibitors in Human Brain Tumors 总被引:16,自引:0,他引:16
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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
63.
64.
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
65.
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
66.
Harder L Gesk S Martin-Subero JI Merz H Hochhaus A Maass E Feller A Grote W Siebert R Fetscher S 《Cancer Genetics and Cytogenetics》2003,142(1):80-82
We describe a patient initially diagnosed with a chronic myeloproliferative disorder in the accelerated phase. Cytogenetic analysis showed the presence of two independent clones. One clone contained a typical Philadelphia (Ph) chromosome due to t(9;22)(q34;q11), as the sole abnormality which was proven molecularly to result in the b2a2-BCR/ABL fusion. The other clone displayed a complex karyotype with several structural and numerical aberrations including trisomy 11 and 22 but lacking a t(9;22) or any other structural abnormalities involving chromosomes 9 and 22. Fluorescence in situ hybridization demonstrated that the t(9;22) was present only in cells with two copies of chromosomes 11 and 22. In contrast, cells with trisomies 11 and 22 lacked evidence for a BCR/ABL fusion. Based on the genetic findings, simultaneous chronic and acute myelocytic leukemias were diagnosed rather than a blastic phase of a chronic myelocytic leukemia. 相似文献
67.
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
68.
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
69.
70.
Virgil Percec Gabriela Zipp Gary Johansson Uwe Beginn Martin Mller 《Macromolecular chemistry and physics.》1997,198(2):265-277
Synthesis and characterization of methacrylate-monofunctionalized crown ether compounds based on derivatives of 2-hydroxymethyl-1,4,7,10,13-pentaoxacyclopentadecane and 4′-hydroxymethyl-1,4,7,10,13-pentaoxabenzocyclopentadecane is described. By differential scanning calorimetry (DSC) and thermooptical analysis (TOA) it is shown that the synthesized compounds and their sodium triflate complexes exhibit columnar mesophases. 相似文献