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排序方式: 共有588条查询结果,搜索用时 15 毫秒
61.
Barbara Rivera Rabea Wagener Nelly Sabbaghian Susanne Bens Benjamin Ellezam Dorothée Bouron‐Dal Soglio Jessica Ordóñez Stephanie Sacharow Jose Fernando Polo Nieto R. Paul Guillerman Gordan M. Vujanic John R. Priest Reiner Siebert William D. Foulkes 《Genes, chromosomes & cancer》2018,57(5):223-230
Germ‐line interstitial deletions involving the 14q32 chromosomal region, resulting in 14q32 deletion syndrome, are rare. DICER1 is a recently described cancer‐predisposition gene located at 14q32.13. We report the case of a male child with a ~5.8 Mbp 14q32.13q32.2 germ‐line deletion, which included the full DICER1 locus. We reviewed available clinical and pathological material, and conducted genetic analyses. In addition to having congenital dysmorphic features, the child developed multiple DICER1 syndrome‐related tumors before age 5 y: a pediatric cystic nephroma (pCN), a ciliary body medulloepithelioma (CBME), and a small lung cyst (consistent with occult pleuropulmonary blastoma Type I/Ir cysts seen in DICER1 mutation carriers). He also developed a cerebral spindle‐cell sarcoma with myogenous differentiation. Our investigations revealed that the deletion encompassed 31 protein‐coding genes. In addition to the germ‐line DICER1 deletion, somatic DICER1 RNase IIIb mutations were found in the CBME (c.5437G > A, p.E1813K), pCN (c.5425G > A, p.G1809R), and sarcoma (c.5125G > A, p.D1709N). The sarcoma also harbored a somatic TP53 mutation: c.844C > T, p.R282W. Additional copy number alterations were identified in the CBME and sarcoma using an OncoScan array. Among the 8 cases with molecularly‐defined 14q32 deletions involving DICER1 and for whom phenotypic information is available, our patient and one other developed DICER1‐related tumors. Biallelic DICER1 mutations have not previously been reported to cause cerebral sarcoma, which now may be considered a rare manifestation of the DICER1 syndrome. Our study shows that DICER1‐related tumors can occur in children with 14q32 deletions and suggests surveillance for such tumors may be warranted. 相似文献
62.
Chassin C Vimont S Cluzeaud F Bens M Goujon JM Fernandez B Hertig A Rondeau E Arlet G Hornef MW Vandewalle A 《Journal of the American Society of Nephrology : JASN》2008,19(12):2364-2374
Uropathogenic Escherichia coli (UPEC) are the most frequent causes of urinary tract infections and pyelonephritis. Renal medullary collecting duct (MCD) cells are the intrarenal site to which UPEC strains prefer to adhere and initiate an inflammatory response, but the ability of UPEC strains to translocate across impermeant MCD cells has not been demonstrated definitively. Here, several UPEC strains adhered to the apical surface and translocated across confluent murine inner MCD cells grown on filters. UPEC strains expressing cytolytic and vacuolating cytotoxins disrupted the integrity of cell layers, whereas noncytolytic UPEC strains passed through the cell layers without altering tight junctions. Apical-to-basal transcellular translocation was dramatically reduced after extinction of Toll-like receptor 4 (TLR4) and the lipid raft marker caveolin-1 by small interfering RNA. Furthermore, disruption of lipid raft integrity by filipin III and methyl-beta-cyclodextrin significantly reduced both the transcellular translocation of UPEC across murine inner MCD cell layers and the stimulation of proinflammatory mediators. Bacterial translocation was also significantly reduced in primary cultures of TLR4-deficient mouse MCD cells compared with MCD cells from wild-type mice. Benzyl alcohol, an anesthetic that enhances membrane fluidity, favored the recruitment of caveolin-1 in lipid rafts and increased the translocation of UPEC across cultured TLR4-deficient MCD cells. These findings demonstrate that the transcellular translocation of UPEC strains across impermeant layers of MCD cells may occur through lipid rafts via a TLR4-facilitated process. 相似文献
63.
YL Cheng CC Shek FK Wong KS Choi KF Chau TS Ing CS Li 《American journal of kidney diseases》1998,31(6):986-990
In 22 hemodialysis patients, during a dialysis session, the solute removal index (SRI) for urea obtained from the use of a partial spent dialysate collection method was compared with that derived from the use of a total spent dialysate collection technique. The partial spent dialysate collection method was used to harvest a small representative sample of the total spent dialysate. The volumes of spent dialysate collected by the partial and the total spent dialysate collection methods were 1.7 +/- 0.4 L and 129.6 +/- 15.3 L, respectively. The total amount of urea nitrogen removed by dialysis as estimated by the partial spent dialysate collection method was similar to that determined by the total spent dialysate collection approach. As a result, the SRI value for urea obtained by the partial spent dialysate collection method (namely, 63% +/- 8%) correlated very well (r = 0.95, P < 0.001) with that derived by the total spent dialysate collection technique (namely, 62% +/- 8%). Our data suggest that it is feasible to use a simple partial spent dialysate collection method to obtain SRI results in patients treated with hemodialysis. 相似文献
64.
65.
We have investigated whether or not tissue factor (TF) which is present in the supernatant of isolated glomeruli, is responsible for the stimulatory activity of TXB2 production by isolated human platelets. Reconstituted TF stimulated TXB2 synthesis in platelets in a dose-dependent manner. This effect was potentiated in the presence of a mixture of the major fatty acids found in glomerular supernatants. Addition of a neutralizing anti-TF monoclonal antibody abolished both the procoagulant activity and the platelet-TXB2 stimulatory activity of reconstituted TF and of glomerular supernatants. Anti-factor VII/VIIa (F VII/VIIa) Fab inhibited in a dose-dependent manner the platelet-TXB2 stimulatory activity of an identical dilution of reconstituted TF and of glomerular supernatants, providing evidence that the functional complex TF. VIIa and not TF itself was the active agent. Pretreatment of platelets, TF or glomerular supernatant by hirudin, an inhibitor of thrombin, as well as by antithrombin III heparin, which inhibits both activated factor X and thrombin also markedly inhibited the synthesis of TXB2 by platelets in the presence of either TF or glomerular supernatant. Taken together, these results demonstrate that the stimulatory activity for TXB2 production by platelets which is released by the glomerular cells is attributable to TF. TF does not act directly. Its effect is mediated by thrombin which is formed de novo at the platelet surface in the presence of even traces of the plasma coagulation proteins associated with platelets. TXB2 formation in platelets correlates well with TF concentration in the glomerular supernatant. The possibility of a similar set of mechanisms associated with glomerular injury may require consideration. 相似文献
66.
67.
Takenoshita S; Hagiwara K; Gemma A; Nagashima M; Ryberg D; Lindstedt BA; Bennett WP; Haugen A; Harris CC 《Carcinogenesis》1997,18(7):1427-1429
The transforming growth factor-beta type II receptor (RII) is commonly
mutated in colon and gastric cancers with microsatellite instability (MI).
We utilized our series of lung cancers with MI and rare alleles of the
H-ras1 gene to determine the association between MI and RII mutations and
searched the entire RII coding region in 33 lung cancers with MI by
polymerase chain reaction-single-strand conformation polymorphism analysis.
We found no mutations, and these data support other recent evidence that
RII mutations rarely occur except in colon and gastric tumors with MI.
相似文献
68.
To investigate the population genetic structure of Trypanosoma evansi from domesticated animals, we have analysed 112 stocks from camels, buffaloes, cattle and horses using the tandemly repeated
coding sequence (MORF2) and minisatellite markers 292 and cysteine-rich acidic integral membrane protein (CRAM). We recorded
a total of six alleles at the MORF2 locus, seven at 292 and 12 at the CRAM loci. Nei’s genetic distance showed reduced allelic
diversity between buffaloes and cattle stocks (1.2) as compared to the diversity between camels and buffaloes (3.75) and camels
and cattle stock (1.69). The mean index of association (I
A
= 0.92) significantly deviated from zero, and the average number of multilocus genotypes (G/N ratio) was 0.21. Twenty-four
multilocus genotypes were defined from the combination of alleles at the three loci. The Kenyan sub-populations showed F
st
= 0.28 and analysis of molecular variance showed significant divergence (22.7%) between the Laikipia, Kulal and Galana regions.
The regional and host distribution of multi-locus genotypes significant population differentiation and high Nei’s genetic
distances suggest existence of genetic sub-structuring within T. evansi stocks while the few multi-locus genotypes and deviation of association index from zero indicate the lack of recombination.
In conclusion, this study reveals that some genetic sub-structuring does occur within T. evansi, which has a clonal population structure. 相似文献
69.
70.
Christabel Enweronu-Laryea Kim E Dickson Sarah G Moxon Aline Simen-Kapeu Christabel Nyange Susan Niermeyer France Bégin Howard L Sobel Anne CC Lee Severin Ritter von Xylander Joy E Lawn 《BMC pregnancy and childbirth》2015,15(Z2):S4