Breakpoint regions of ETO gene involved in (8; 21) leukemic translocations are enriched in acetylated histone H3.

One of the most frequent chromosomal translocation found in patients with acute myeloid leukemia (AML) is the t(8;21). This translocation involves the RUNX1 and ETO genes. The breakpoints regions for t(8;21) are located at intron 5 and intron 1 of the RUNX1 and ETO gene respectively.

Estrogen receptors in mast cells from arterial walls.

We examined the presence of estrogen receptors (ER) in vascular mast cells and a possible genomic effect of estrogens on the expression of mast cell (MC) mediators such as chymase, TNF alpha, NOS and IL-10, which are known to affect the course of atherosclerosis. Immunocytochemical detection of mast cell tryptase and the co-localization of ERs in MCs from abdominal aortic vessels from 10 fertile woman, 10 postmenopausal women and 15 men was performed. The genomic expression of IL-10, TNF alpha, and NOS was analyzed by RT-PCR and chymase activity by spectrophotometry after 24 h incubation with 17-beta estradiol (0.

Characterization of mast cells according to their content of tryptase and chymase in normal and neoplastic human uterine cervix.

Mast cells (MC) have been associated with diverse human cancers. The primary function of these cells is to store and release a number of biologically active mediators, including the serine proteases tryptase and chymase. These proteases have been closely related with angiogenesis and tumor invasion, two critical steps during tumor progression.

Xanthine oxidase released from reperfused hind limbs mediate kupffer cell activation, neutrophil sequestration, and hepatic oxidative stress in rats subjected to tourniquet shock.

We have shown previously that rats subjected to tourniquet shock develop an acute form of remote organ injury of the liver that is both Kupffer cell (KC) and polymorphonuclear (PMN) leukocyte dependent. Circulating plasma xanthine oxidase (XO) has been shown to be responsible for the development of endothelial dysfunction and for remote organ injury of the lung and intestine after ischemia-reperfusion protocols. We now hypothesize that XO is released from rat hind limbs upon reperfusion and that it is responsible for KC and PMN leukocyte activation in this shock model.

Ethodin: pharmacological evidence of the interaction between smooth muscle and mast cells in the myometrium.

Ethodin has been used to induce labor through a mechanism that does not involve the estrogen-preparatory process being postulated as necessary for ensuring the events in a normal labor. The cellular mechanisms involved in that process are unknown. We used an isolated organ bath preparation for mouse uterine horns and a primary culture of mouse myometrial smooth muscle cells to analyze the cellular mechanisms involved in the contractile action of this drug in the myometrium.

Influence of the HLA-DR beta shared epitope on susceptibility to and clinical expression of rheumatoid arthritis in Chilean patients.

Objective: To analyse the influence of shared epitope positive HLA-DRB1 alleles (QKRAA or QRRAA)) on rheumatoid arthritis (RA) susceptibility and severity in Chileans, a population that exhibits a weak association with HLA-DR4.

Methods: Prevalence of alleles DRB1*01 and DRB1*04 alleles was determined by polymerase chain reaction amplification and sequence specific oligonucleotide hybridisation in 129 RA patients with defined clinical features and in 97 healthy controls.

Results: The shared epitope was found in 70 (54%) of the RA patients and in 29 (30%) of controls (odds ratio (OR) = 3; 95% confidence intervals (CI) = 1.

Clinical expression of rheumatoid arthritis in Chilean patients.

In populations such as Northern Europeans in which the HLA-DR4 subtypes DW14 and Dw4 show strong association with rheumatoid arthritis (RA), these alleles and the double allelic dose of the shared epitope are considered severity markers. The clinical expression of RA varies in different populations, which may be determined by variation in the prevalence of these markers. In the present study we analyzed the expression of RA in 112 consecutive Chilean patients and its relation to the prevalence of genetic factors, prompted by our previous observation that DR4 is weakly associated to RA in this population.

Apical secretion of hepatitis B surface antigen from transfected Madin-Darby canine kidney cells.

Hepatitis B surface antigen (HBsAg), the major envelope component of human hepatitis B virus, during infection drives the assembly and basolateral secretion from hepatocytes of both virions and subviral lipoprotein particles into the bloodstream. We studied the sorting behavior of HBsAg in the heterologous epithelial Madin-Darby canine kidney cells permanently transformed with the hepatitis B virus S gene. These cells, forming tightly packed monolayers in permeable supports, secreted HBsAg apically through a mechanism not involving transcytosis.

Novel genetic markers of rheumatoid arthritis in Chilean patients, by DR serotyping and restriction fragment length polymorphism analysis.

Objective: The analysis of genetic markers of rheumatoid arthritis (RA) in a population in which the DR4 serotype is not strongly associated with the disease.

Methods: Chilean RA patients (56 seropositive and 22 seronegative) and 141 controls were studied by serotyping. Southern blot analysis of Bam HI restriction fragment length polymorphism (RFLP) was done in genomic DNA from 46 patients with seropositive RA, 17 patients with seronegative RA, and 45 controls, using a complementary DNA probe specific for DRB1 genes.