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排序方式: 共有1159条查询结果,搜索用时 9 毫秒
1.
PJ Commerford 《Cardiovascular journal of Africa》2015,26(4):151-Aug;26(4):151
2.
E. B. Austin F. Thistlethwaite S. Neeson P. Stern L. McDonald M. Hulston D. Gilham E. Elkord R. Griffiths R. Guest J. D. M. Campbell R. E. Hawkins 《Transfusion medicine (Oxford, England)》2006,16(Z1):8-8
The CXCL12/CXCR4 chemokine axis is a well characterized and important chemotactic stimulus/receptor unit that orchestrates the homing and migration of cells to the bone marrow and to ischemic tissues following tissue damage. Here, we demonstrate that the sialomucin, CD164, a regulator of haemopoietic precursor cell adhesion to stroma and entry of primitive CD34+CD38lo/‐ precursor cells into cycle, modulates the migration of CD133+ cord blood cells to CXCL12 by associating with the CXCR4 receptor. This was demonstrated by a reduction in CD133+ cell migration on fibronectin to CXCL12 (i) by engaging the functional class II glycosylation‐dependent epitope on CD164 with the 103B2/9E10 class II but not the N6B6 class III antibody; and (ii) by RNAi knockdown of CD164 protein levels in CD133+ cells. The inhibition of migration was more pronounced in the more primitive CD34+CD38lo/‐ cell subset. Similar studies using the Jurkat cell line confirmed these findings and led to further analyses using alternative chemokines. A direct association between CXCR4 and CD164 was demonstrated by the co‐localisation of CD164 with CXCR4 and VLA‐4 and VLA‐5 at the leading edge of CD133+ cells when CXCL12 was presented on fibronectin. This was further supported by immunoprecipitation studies that demonstrate in the absence of CXCL12, CXCR4 is associated only with VLA‐4 and VLA‐5 but on exposure to CXCL12, CD164 is rapidly recruited to the CXCR4 complex. Knock‐down of CD164 using siRNA revealed that signalling through CXCR4 via PKC‐ζ was significantly dampened. Our findings therefore support a novel association between three distinct families of cell surface receptors that regulate both cell migratory and proliferative responses and identify a CD164 as a key regulator of the CXCL12/CXCR4 axis. 相似文献
3.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease. 相似文献
4.
5.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
6.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献
7.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
8.
Hendrickx J; Dams E; Coucke P; Lee P; Fernandes J; Willems PJ 《Human molecular genetics》1996,5(5):649-652
X-linked liver glycogenosis type II (XLG II) is a recently described X-
linked liver glycogen storage disease, mainly characterized by enlarged
liver and growth retardation. These clinical symptoms are very similar to
those of XLG I. In contrast to XLG I patients, however, XLG II patients do
not show an in vitro enzymatic deficiency of phosphorylase kinase (PHK).
Recently, mutations were identified in the gene encoding the liver alpha
subunit of PHK (PHKA2) in XLG I patients. We have now studied the PHKA2
gene of four unrelated XLG II patients and identified four different
mutations in the open reading frame, including a deletion of three
nucleotides, an insertion of six nucleotides and two missense mutations.
These results indicate that XLG II is due to mutations in PHKA2. In
contrast to XLG I, XLG II is caused by mutations that lead to minor
structural abnormalities in the primary structure of the liver alpha
subunit of PHK. These mutations are found in a conserved RXX(X)T motif,
resembling known phosphorylation sites that might be involved in the
regulation of PHK. These findings might explain why the in vitro PHK
enzymatic activity is not deficient in XLG II, whereas it is in XLG I.
相似文献
9.
10.
Thomas R Johansson A Neeson B Isherwood K Sjöstedt A Ellis J Titball RW 《Journal of clinical microbiology》2003,41(1):50-57
We describe the use of two insertion sequence elements (ISFtu1 and ISFtu2) in Francisella tularensis to type strains by restriction fragment length polymorphism (RFLP). The RFLP profiles of 17 epidemiologically unrelated isolates were determined and compared. Our results showed that RFLP profiles can be used to assign F. tularensis strains into five main groups corresponding to strains of F. tularensis subsp. tularensis, F. tularensis strain ATCC 6223, strains of F. tularensis subsp. holarctica, strains of F. tularensis subsp. holarctica from Japan, and F. tularensis subsp. mediaasiatica. The results confirm the genetic identities of these subspecies and also support the suggestion that strains of F. tularensis subsp. holarctica from Japan should be considered members of a separate biovar. These findings should support future studies to determine the genetic differences between strains of F. tularensis at the whole-genome level. 相似文献