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Genome-wide analysis of single nucleotide polymorphisms in 64 acute myeloid leukemias has revealed that approximately 20% exhibited large regions of homozygosity that could not be accounted for by visible chromosomal abnormalities in the karyotype. Further analysis confirmed that these patterns were due to partial uniparental disomy (UPD). Remission bone marrow was available from five patients showing UPD in their leukemias, and in all cases the homozygosity was found to be restricted to the leukemic clone. Two examples of UPD11p were shown to be of different parental origin as indicated by the methylation pattern of the H19 gene. Furthermore, a previously identified homozygous mutation in the CEBPA gene coincided with a large-scale UPD on chromosome 19. These cryptic chromosomal abnormalities, which seem to be nonrandom, have the characteristics of somatic recombination events and may define an important new subclass of leukemia.  相似文献   
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Genome-wide single nucleotide polymorphism analysis has revealed large-scale cryptic regions of acquired homozygosity in the form of segmental uniparental disomy in approximately 20% of acute myeloid leukemias. We have investigated whether such regions, which are the consequence of mitotic recombination, contain homozygous mutations in genes known to be mutational targets in leukemia. In 7 of 13 cases with uniparental disomy, we identified concurrent homozygous mutations at four distinct loci (WT1, FLT3, CEBPA, and RUNX1). This implies that mutation precedes mitotic recombination which acts as a "second hit" responsible for removal of the remaining wild-type allele, as has recently been shown for the JAK2 gene in myeloproliferative disorders.  相似文献   
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The study aimed to produce solid lipid insulin-loaded micro-particles by the solvent-in-water emulsion-diffusion technique, using isobutyric acid as solvent phase, glyceryl monostearate or cetyl palmitate as lipid, soya lecithin and taurodeoxycholate as emulsifiers. Isobutyric acid, a partially water-miscible solvent with low toxicity, was used due to its high insulin-solubilization capacity. Solid lipid micro-particles of spherical shape were prepared by simple dilution of the emulsion with water. To increase the lipid load the process was conducted at 50 degrees C, and in order to reach sub-micron size, a high-shear homogeniser was used. Insulin encapsulation efficiency was about 80%. Analysis of microsphere content after processing showed that insulin did not undergo any chemical modification within the micro-particles. The in vitro release of insulin from the micro-particles was very low, and an initial burst effect of 20% of the dose was observed. After treatment of the solid lipid micro-particles with pepsin solution, an insulin loss of about 24% of the total englobed insulin was observed. The solid lipid micro-particles appear to have interesting possibilities as delivery systems for oral administration of insulin.  相似文献   
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Background  

The intraoperative epidural analgesia (EA) has the potential to reduce stress response to surgical trauma which induces a transient immunoactivation that has a negative impact on the outcome. This study investigates the effect of intraoperative EA versus intravenous analgesia (IA) on the immune function.  相似文献   
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British Journal of Pharmacology (BJP) is pleased to publish a new set of guidelines for reporting research involving animals, simultaneously with several other journals; the ‘ARRIVE’ guidelines (Animals in Research: Reporting In Vivo Experiments). This editorial summarizes the background to the guidelines, gives our view of their significance, considers aspects of specific relevance to pharmacology, re-states BJP''s guidelines for authors on animal experiments and indicates our commitment to carrying on discussion of this important topic. We also invite feedback via the British Pharmacological Society website.  相似文献   
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Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.  相似文献   
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