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71.
The role of COX-2 in angiogenesis and rheumatoid arthritis 总被引:4,自引:0,他引:4
Woods JM Mogollon A Amin MA Martinez RJ Koch AE 《Experimental and molecular pathology》2003,74(3):282-290
Recent evidence suggests that cyclooxygenase (COX)-2 is a mediator of angiogenesis, and COX-2 activity is known to be upregulated in the rheumatoid arthritis (RA) synovium. We examined whether mediation of angiogenesis by COX-2 was occuring in cells of the RA synovium and in microvascular endothelial cells (ECs) that are similar to those found in the RA synovium. We demonstrate that rofecoxib, a selective COX-2 inhibitor, acts directly on human dermal microvascular ECs (HMVECs) to inhibit their chemotactic and tube forming ability. Likewise, pretreatment of HMVECs with rofecoxib significantly inhibited their ability to form tubes induced by conditioned media (CM) of activated RA synovial fibroblasts. When RA synovial fibroblasts were pretreated with rofecoxib for 16 h and then stimulated with interleukin (IL)-1beta, their CM induced significantly less HMVEC tube formation when compared with CM from vehicle-treated RA synovial fibroblasts. ELISAs performed on activated RA fibroblast CM for known proangiogenic factors demonstrated a significant reduction in bFGF, in addition to the expected decrease in PGE(2). Our studies suggest that COX-2-induced angiogenic activity is an active mechanism within diseased synovium and may provide an additional rationale for the use of COX-2 inhibitors in RA. 相似文献
72.
Weitkunat R Markuzzi A Vogel S Schlipköter U Koch HJ Meyer G Ferring D 《Journal of health psychology》1998,3(2):273-284
A cross-sectional study of 8204 children was performed to investigate the prevalence of immunization against measles, mumps and rubella and possible determinants of immunization uptake. The study was approached from a Lewinian perspective on preventive behaviour. Seventy-one questions referring to the guardian of the child, his or her partner, the household and the child, as well as to immunization-related experiences and situational topics were asked. Two psychological variables were studied: health locus of control and subjective relevance concerning measles. The immunization rate was 77.7 percent [95 percent confidence interval 76.8-78.6]. Multiple logistic regression yielded the following odds ratios for non- uptake of measles immunization: natural health orientation 8.74 [6.72-11.37]; advice of paediatrician 6.02 [4.67-7.75]; dangerousness of measles 2.00 [1.53-2.60]; marital status 1.87 [1.31-2.51]; assessed reliability of vaccination 1.57 [1.23-2.01]; smoking 1.55 [1.21-1.98]; and number of siblings 1.55 [1.21- 1.98]. Parents or guardians of immunized children were more internal and assessed measles as more relevant than those of non- immunized children. 相似文献
73.
Zach Koch Leiber H. G. Lasch Weicker 《Journal of molecular medicine (Berlin, Germany)》1955,33(19-20):500-501
74.
The aim of this study was to establish an enzyme-linked immunosorbent assay (ELISA) to measure IgG subclasses by means of monoclonal antibodies. The distribution of IgG subclass protein concentrations in sera from 227 healthy Danish children and 90 adults was measured. Furthermore, this newly established ELISA was compared with different assay systems for determination of IgG subclasses: two radial immunodiffusion methods (RID), one using polyclonal and one using monoclonal antibodies, as well as a commercially available ELISA kit. There was good agreement of results obtained by the different methods of measuring IgG3 and IgG4 concentrations. There was good correlation between results obtained by both RID methods. Despite good correlation between the assays, the ELISA kit showed higher levels of IgG1 in all investigated sera, and the ELISA kit showed no correlation with the other methods, when IgG2 was measured. Analysis of the normal ranges measured by ELISA developed in our laboratory and by RID with polyclonal antibodies showed that the levels obtained by RID were higher than those obtained by our ELISA in sera with low levels of both IgG1 and IgG2, and lower in sera with high concentrations of these two immunoglobulins. Our results emphasize the importance of establishing age-related normal limits for any novel assay measuring IgG subclass concentrations. 相似文献
75.
The control of retinogeniculate transmission in the mammalian lateral geniculate nucleus 总被引:13,自引:0,他引:13
S. M. Sherman C. Koch 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,63(1):1-20
Summary In the mammalian visual system, the lateral geniculate nucleus is commonly thought to act merely as a relay for the transmission of visual information from the retina to the visual cortex, a relay without significant elaboration in receptive field properties or signal strength. However, many morphological and electrophysiological observations are at odds with this view. Only 10–20% of the synapses found on geniculate relay neurons are retinal in origin. Roughly half of all synapses derive from cells in layer VI of visual cortex; roughly one third are inhibitory and GABAergic, derived either from interneurons or from cells of the nearby perigeniculate nucleus. Most of the remaining synapses probably derive from cholinergic, noradrenergic, and serotonergic sites within the brainstem reticular formation. Moreover, recent biophysical studies have revealed several ionic currents present in virtually all thalamic neurons. One is a Ca2+-dependent K+ current underlying the afterhyperpolarization (or the IAHP), which may last up to 100–200 ms following an action potential. Activation of the IAHP leads to spike frequency adaptation in response to a sustained, suprathreshold input. Intracellular recordings from other neuronal preparations have shown that the IAHP can be blocked by noradrenalin or acetylcholine, leading to an increased cellular excitability. Another ionic current results from a voltage- and time-dependent Ca2+ conductance that produces a low threshold spike. Activation of this conductance transforms a geniculate neuron from a state of faithful relay of information to one of bursting behavior that bears little relationship to the activity of its retinal afférents. We propose that state-dependent gating of geniculate relay cells, which may represent part of the neuronal substrate involved in certain forms of selective visual attention, can be effected through at least three different mechanisms: (1) conventional GABAergic inhibition, which is largely controlled via brainstem and cortical afferents through interneurons and perigeniculate cells; (2) the IAHP, which is controlled via noradrenergic and cholinergic afferents from the brainstem reticular formation; and (3) the low threshold spike, which may be controlled by GABAergic inputs, cholinergic inputs, and/or the corticogeniculate input, although other possibilities also exist. Furthermore, it seems likely that gating functions involving the corticogeniculate pathway are suited to attentional processes within the visual domain (e.g., saccadic suppression), whereas brain-stem inputs seem more likely to have more global effects that switch attention between sensory systems. In any case, it is now abundantly clear that geniculate circuitry and the intrinsic electrophysiological properties of geniculate neurons are no longer compatible with the notion that the lateral geniculate nucleus serves as a simple relay. 相似文献
76.
77.
Excised mouse pubic bone rudiments were exposed to H3-thymidine. Rudiments preserved immediately after exposure consisted of mesenchyme with a large number of cells showing intense radioactivity. Rudiments incubated on a filter membrane after exposure went through the developmental stages of complete chondrification of the pubic rami followed by periosteal and then endochondral bone formation. Only chondrocytes showed radioactivity in rami consisting of cartilage and periosteal bone that were preserved prior to endochondral ossification. Cell types showing radioactivity in rami preserved during endochondral ossification were chondrocytes, chondroclasts, and osteoblasts and osteocytes of endochondral bone. The results of the study demonstrated that hypertrophic chondrocytes of the calcified cartilage of a developing mammalian long bone not only survive dissolution of their matrix, but transform into chondroclasts and osteoprogenitor cells that give rise to osteoblasts and osteocytes which form endochondral bone in the absence of blood vessels. 相似文献
78.
79.
Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency 总被引:1,自引:0,他引:1
Hong YS; Kerr DS; Craigen WJ; Tan J; Pan Y; Lusk M; Patel MS 《Human molecular genetics》1996,5(12):1925-1930
An infant girl with elevated blood lactate, pyruvate, and plasma
branched-chain amino acids was diagnosed with dihydrolipoamide
dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4)
deficiency. Activities of the pyruvate dehydrogenase complex and E3 from
patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in
cultured skin fibroblasts, respectively. Western blot analysis demonstrated
that the amount of E3 protein in fibroblasts from the patient and her
father was about half of controls, while Northern blot analysis showed
normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs
from the patient revealed two mutations in separate alleles. One is a
single base insertion of an extra adenine in the last codon of the leader
peptide sequence (TAC-->TAAC) leading to a nonsense mutation which
results in the premature termination of the precursor E3 polypeptide
(Y35X). The other is a missense mutation due to substitution of guanine for
adenine, causing an Arg-->Gly substitution at amino acid 460 of the
mature protein (R460G) which triggers the loss of E3 activity probably by
structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the
parents demonstrated that the nonsense mutation was inherited from the
father and the missense mutation was inherited from the mother.
相似文献
80.