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1.
Paulsson K Fioretos T Strömbeck B Mauritzson N Tanke HJ Johansson B 《Cancer Genetics and Cytogenetics》2003,140(1):66-69
Trisomy 8 is the most common chromosomal aberration in myelocytic malignancies, occurring both as a sole change as well as in addition to other abnormalities. In spite of this, next to nothing is known about its pathogenetic importance or its molecular genetic consequences. Possible mechanisms involved in the transformation process include dosage effects of genes mapping to chromosome 8 and presence of specific mutations or cryptic fusion genes on the duplicated chromosome. In the latter case, +8 would be secondary to a cryptic primary rearrangement and not involved in leukemogenesis as such, but rather in tumor evolution. Although hidden genetic changes have been found in some trisomies, for example, mutations in KIT in acute myelocytic leukemia (AML) with +4 and in MET in hereditary papillary kidney carcinoma with trisomy 7, none associated with +8 have so far been discovered. To address this issue, we have investigated a total of 13 cases of AML, myelodysplastic syndromes, and chronic myeloproliferative disorders with trisomy 8 as the sole chromosomal anomaly. All cases were studied by combined binary ratio multicolor fluorescence in situ hybridization (FISH) and with FISH using locus-specific probes for both arms of chromosome 8, the subtelomeric regions of 8p and 8q, and the leukemia-associated genes FGFR1, MOZ, ETO, and MYC. No cryptic changes were detected, thus excluding the possibility of gross genetic rearrangements or aberrations involving these loci on chromosome 8. 相似文献
2.
Particle agglutination assays for rapid detection of fibronectin, fibrinogen, and collagen receptors on Staphylococcus aureus. 总被引:4,自引:5,他引:4
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Latex beads (0.8-micron diameter; Difco Laboratories) were coated with fibronectin, fibrinogen, collagen type I, or denatured collagen (gelatin) and evaluated in a particle agglutination assay (PAA) for the rapid detection of fibronectin, fibrinogen, or collagen binding to Staphylococcus aureus. These assays were compared with a commercial test for detecting the binding of fibrinogen and immunoglobulin G (Staphaurex). Bacterial cells (approximately 10(10) cells per ml) suspended in 0.02 M potassium phosphate buffer (pH 6.8) caused the clumping of standard fibronectin, collagen, gelatin, and fibrinogen latex suspensions within 2 min on glass slides. The test results were scored semiquantitatively from strongly positive ( ) to weakly positive (+) and negative (-) reactions. The negative PAA reactions corresponded to a median value of 11.5% relative to the binding of 125I-labeled protein to strain Cowan 1, indicating the high sensitivity of the test. The reactions with fibronectin and fibrinogen latex suspensions and with Staphaurex were optimal for cells grown on tryptic soy and brain heart infusion broth media. Blood agar was optimal for reactions with collagen and gelatin latex suspensions. Media containing high salts (mannitol salt agar and staphylococcus medium 110) enhanced the tendency of cells to autoaggregate. These assays were also clinically evaluated on 187 S. aureus isolates. The PAA reagents were stable, and the assays were highly specific, sensitive, and reproducible, thus making PAA suitable for the rapid screening of the binding of various bacterial pathogens to serum and connective-tissue proteins. 相似文献
3.
Storlazzi CT Fioretos T Paulsson K Strömbeck B Lassen C Ahlgren T Juliusson G Mitelman F Rocchi M Johansson B 《Human molecular genetics》2004,13(14):1479-1485
Double minutes (dmin), the cytogenetic hallmark of genomic amplification, are found in approximately 1% of karyotypically abnormal acute myeloid leukemias (AML) and myelodysplastic syndromes (MDS). The MYC gene at 8q24 has been reported to be amplified in the majority of the cases, and generally it has been assumed that MYC is the target gene. However, only a few studies have focused on the extent of the amplicon or on the expression patterns of the amplified genes. We have studied six cases (five AML and one MDS) with MYC-containing dmin. Detailed fluorescence in situ hybridization analyses identified a common 4.3 Mb amplicon, with clustered proximal and distal breakpoints, harboring eight known genes (C8FW, NSE2, POU5FLC20, MYC, PVT1, AK093424, MGC27434 and MLZE). The corresponding region was deleted in one of the chromosome 8 homologues in five of the six cases, suggesting that the dmin originated through extra replication (or loop-formation)--excision--amplification. Northern blot analysis revealed that MYC was not overexpressed. Instead, the C8FW gene, encoding a phosphoprotein regulated by mitogenic pathways, displayed increased expression. These results exclude MYC as the target gene and indicate that overexpression of C8FW may be the functionally important consequence of 8q24 amplicons in AML and MDS. 相似文献
4.
Paulsson KM Wang P Anderson PO Chen S Pettersson RF Li S 《International immunology》2001,13(8):1063-1073
In this study we have compared the interaction of human MHC class I molecules with IgG heavy chain (HC) binding protein (BiP), calnexin, calreticulin, tapasin and TAP in beta(2)-microglobulin (beta(2)m)- or TAP-deficient cells, as well as in wild-type B-LCL cells. Distinct differences between the association of HC and these endoplasmic reticulum (ER) proteins were found in the three cell lines. In the absence of beta(2)m (Daudi cells), HC associated with both BiP and calnexin. A prominent portion of HC was complexed simultaneously to both chaperones, as indicated by co-precipitation with either anti-calnexin or anti-class I antisera. In the presence of beta(2)m, but absence of TAP (T2 cells), HC could be co-precipitated with calnexin, whereas no detectable interaction with BiP could be demonstrated. This suggests that calnexin interacts with HC at a later stage than BiP. In B-LCL cells, HC-beta(2)m associated with calreticulin and tapasin, whereas no interaction with calnexin and BiP was observed. In the absence of beta(2)m, HC were rapidly degraded in the ER, while the ER retained HC were stabilized in the presence of beta(2)m, even in the absence of TAP. The dissociation of class I molecules from TAP in B-LCL cells correlated with the kinetics of appearance of class I molecules on the cell surface, suggesting that TAP retains peptide-free class I molecules in the ER. Taken together, our results suggest the model that BiP and calnexin sequentially control the folding of MHC class I, before MHC class I molecules associate with the loading complex. 相似文献
5.
Katia Keglberg Hrvig Kajsa Ugelvig Petersen Karin Srig Hougaard Christian Lindh Cecilia Hst Ramlau-Hansen Gunnar Toft Aleksander Giwercman Birgit Bjerre Hyer Esben Meulengracht Flachs Jens Peter Bonde Sandra Sgaard Tttenborg 《Environmental health perspectives》2022,130(10)
Background: Concerns remain about the human reproductive toxicity of the widespread per- and polyfluoroalkyl substances (PFAS) during early stages of development.Objectives: We examined associations between maternal plasma PFAS levels during early pregnancy and male offspring reproductive function in adulthood.Methods: The study included 864 young men (age range:18.9–21.2 y) from the Fetal Programming of Semen Quality (FEPOS) cohort established between 2017 and 2019. Plasma samples from their mothers, primarily from the first trimester, were retrieved from the Danish National Biobank and levels of 15 PFAS were measured. Seven PFAS had detectable levels above the limit of detection in of the samples and were included in analyses. Semen quality, testicular volume, and levels of reproductive hormones and PFAS were assessed in the young men. We used weighted quantile sum (WQS) regression to estimate the associations between combined exposure to maternal PFAS and reproductive function, and negative binomial regression to estimate the associations of single substances, while adjusting for a range of a priori–defined fetal and postnatal risk factors.Results: By a 1-unit increase in the WQS index, combined maternal PFAS exposure was associated with lower sperm concentration (; 95% CI: , ), total sperm count (; 95% CI: , ), and a higher proportion of nonprogressive and immotile sperm (5%; 95% CI: 1%, 8%) in the young men. Different PFAS contributed to the associations with varying strengths; however, perfluoroheptanoic acid was identified as the main contributor in the analyses of all three outcomes despite the low concentration. We saw no clear association between exposure to maternal PFAS and testicular volume or reproductive hormones.Discussion: In a sample of young men from the general Danish population, we observed consistent inverse associations between exposure to maternal PFAS and semen quality. The study needs to be replicated in other populations, taking combined exposure, as well as emerging short-chain PFAS, into consideration. https://doi.org/10.1289/ EHP10285相似文献
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10.
Holgeir Skjeie Trygve Skonnord Mette Brekke Atle Klovning Arne Fetveit Kajsa Landgren 《Scandinavian journal of primary health care》2018,36(1):56-69
Objective: Needle acupuncture in small children has gained some acceptance in Western medicine. It is controversial, as infants and toddlers are unable to consent to treatment. We aimed to assess its efficacy for treating infantile colic.Design: A systematic review and a blinding-test validation based on individual patient data from randomised controlled trials. Primary end-points were crying time at mid-treatment, at the end of treatment and at a 1-month follow-up. A 30-min mean difference (MD) in crying time between acupuncture and control was predefined as a clinically important difference. Pearson’s chi-squared test and the James and Bang indices were used to test the success of blinding of the outcome assessors [parents].Eligibility criteria and data sources: We included randomised controlled trials of acupuncture treatments of infantile colic. Systematic searches were conducted in Cochrane CENTRAL, MEDLINE, EMBASE, CINAHL and AMED, and in the Chinese language databases CNKI, VIP, Wang fang, SinoMed and Chinese Clinical Trial Registry.Results: We included three randomised controlled trials with data from 307 participants. Only one of the included trials obtained a successful blinding of the outcome assessors in both the acupuncture and control groups. The MD in crying time between acupuncture intervention and no acupuncture control was ?24.9?min [95% confidence interval, CI ?46.2 to ?3.6; three trials] at mid-treatment, ?11.4?min [95% CI ?31.8 to 9.0; three trials] at the end of treatment and ?11.8?min [95% CI ?62.9 to 39.2; one trial] at the 4-week follow-up. The corresponding standardised mean differences [SMDs] were ?0.23 [95% CI ?0.42 to ?0.06], ?0.10 [95% CI ?0.29 to 0.08] and ?0.09 [95% CI ?0.48 to 0.30]. The heterogeneity was negligible in all analyses. The statistically significant result at mid-treatment was lost when excluding the apparently unblinded study in a sensitivity analysis: MD ?13.8?min [95%CI ?37.5 to 9.9] and SMD ?0.13 [95%CI ?0.35 to 0.09]. The registration of crying during treatment suggested more crying during acupuncture [odds ratio 7.7; 95% CI 2.7–20.6; one trial]. GRADE-Moderate quality evidence.Conclusions: Percutaneous needle acupuncture treatments should not be recommended for infantile colic on a general basis.Systematic review registration: PROSPERO 2015:CRD42015023253
- Key points
The role of acupuncture in the treatment of infantile colic is controversial. Available trials are small and present conflicting results.
There were no clinically important differences between infants receiving acupuncture and no acupuncture control in this IPD meta-analysis of randomised controlled trials.
The data indicate that acupuncture induces some treatment pain in many of the children.
The study results indicate that percutaneous needle acupuncture should not be recommended for treatment of infantile colic on a general basis.