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131.
Acute promyelocytic leukemia (APL) is characterized by a reciprocal translocation t(15;17)(q22;q21) leading to the disruption of Promyelocytic leukemia (PML) and Retionic Acid Receptor Alpha (RARA) followed by reciprocal PML-RARA fusion in 90% of the cases. Fluorescence in situ hybridization (FISH) has overcome the hurdles of unavailability of abnormal and/or lack of metaphase cells, and detection of cryptic, submicroscopic rearrangements. In the present study, besides diagnostic approach we sought to analyze these cases for identification and characterization of cryptic rearrangements, deletion variants and unknown RARA translocation variants by application of D-FISH and RARA break-apart probe strategy on interphase and metaphase cells in a large series of 200 cases of APL. Forty cases (20%) had atypical PML-RARA and/or RARA variants. D-FISH with PML/RARA probe helped identification of RARA insertion to PML. By application of D-FISH on metaphase cells, we documented that translocation of 15 to 17 leads to 17q deletion which results in loss of reciprocal fusion and/or residual RARA on der(17). Among the complex variants of t(15;17), PML-RARA fusion followed by residual RARA insertion closed to PML-RARA on der(15) was unique and unusual. FISH with break-apart RARA probe on metaphase cells was found to be a very efficient strategy to detect unknown RARA variant translocations like t(11;17)(q23;q21), t(11;17)(q13;q21) and t(2;17)(p21;q21). These findings proved that D-FISH and break-apart probe strategy has potential to detect primary as well as secondary additional aberrations of PML, RARA and other additional loci. The long-term clinical follow-up is essential to evaluate the clinical importance of these findings.  相似文献   
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Molecular Biology Reports - The present study is an effort to understand the genomic drivers of lactation in Sahiwal (Bos indicus), the best milch cattle breed of the tropics. RNA sequencing of...  相似文献   
133.
Low-temperature sweetening (LTS) results when tubers of potato ( Solanum tuberosum ) are stored at temperatures below 9–10°C with the accumulation of sucrose and reducing sugars glucose and fructose. Our earlier study showed that the LTS-tolerant varieties have higher ethanol and lactate tissue levels compared with the LTS-susceptible variety Monona ( Blenkinsop et al. 2003 ), which led us to investigate the role of the anaerobic respiratory pathway in LTS tolerance. The anaerobic respiratory enzymes alcohol dehydrogenase (ADH), l -lactate dehydrogenase (LDH) and pyruvate decarboxylase (PDC) were, therefore, investigated in LTS-tolerant and -susceptible potato varieties. A positive correlation ( P ≤ 0.05) was observed between reducing sugar concentration and the K M of PDC, with the LTS-tolerant ND 860-2 possessing a lower K M and reducing sugar content than the LTS-susceptible Monona variety. The moderately LTS-tolerant variety, Snowden, exhibited intermediate behavior between the two aforementioned cultivars at 4°C. The isozyme profile of the tolerant varieties differed from the susceptible variety. Two groups of LDH isozyme families were observed in all varieties with the exception of ND 860-2, where the second group appeared only during low-temperature exposure. Moreover, the tolerant variety possessed one additional ADH isozyme. Gene expression levels of these enzymes were higher in ND 860-2 as compared with Monona at 4°C. The above results suggest that the anaerobic respiratory enzymes contribute to LTS-tolerance.  相似文献   
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The PR interval on the electrocardiogram reflects atrial and atrioventricular nodal conduction time. The PR interval is heritable, provides important information about arrhythmia risk, and has been suggested to differ among human races. Genome-wide association (GWA) studies have identified common genetic determinants of the PR interval in individuals of European and Asian ancestry, but there is a general paucity of GWA studies in individuals of African ancestry. We performed GWA studies in African American individuals from four cohorts (n = 6,247) to identify genetic variants associated with PR interval duration. Genotyping was performed using the Affymetrix 6.0 microarray. Imputation was performed for 2.8 million single nucleotide polymorphisms (SNPs) using combined YRI and CEU HapMap phase II panels. We observed a strong signal (rs3922844) within the gene encoding the cardiac sodium channel (SCN5A) with genome-wide significant association (p<2.5×10−8) in two of the four cohorts and in the meta-analysis. The signal explained 2% of PR interval variability in African Americans (beta  = 5.1 msec per minor allele, 95% CI  = 4.1–6.1, p = 3×10−23). This SNP was also associated with PR interval (beta = 2.4 msec per minor allele, 95% CI = 1.8–3.0, p = 3×10−16) in individuals of European ancestry (n = 14,042), but with a smaller effect size (p for heterogeneity <0.001) and variability explained (0.5%). Further meta-analysis of the four cohorts identified genome-wide significant associations with SNPs in SCN10A (rs6798015), MEIS1 (rs10865355), and TBX5 (rs7312625) that were highly correlated with SNPs identified in European and Asian GWA studies. African ancestry was associated with increased PR duration (13.3 msec, p = 0.009) in one but not the other three cohorts. Our findings demonstrate the relevance of common variants to African Americans at four loci previously associated with PR interval in European and Asian samples and identify an association signal at one of these loci that is more strongly associated with PR interval in African Americans than in Europeans.  相似文献   
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Granulysin is expressed as two isoforms by human cytotoxic cells: a single mRNA gives rise to 15 kDa granulysin, a portion of which is cleaved to a 9 kDa protein. Studies with recombinant 9 kDa granulysin have demonstrated its cytolytic and proinflammatory properties, but much less is known about the biologic function of the 15 kDa isoform. In this study, we show that the subcellular localization and functions of 9 and 15 kDa granulysin are largely distinct. Nine kilodalton granulysin is confined to cytolytic granules that are directionally released following target cell recognition. In contrast, 15 kDa granulysin is located in distinct granules that lack perforin and granzyme B and that are released by activated cytolytic cells. Although recombinant 9 kDa granulysin is cytolytic against a variety of tumors and microbes, recombinant 15 kDa granulysin is not. The 15 kDa isoform is a potent inducer of monocytic differentiation to dendritic cells, but the 9 kDa isoform is not. In vivo, mice expressing granulysin show markedly improved antitumor responses, with increased numbers of activated dendritic cells and cytokine-producing T cells. Thus, the distinct functions of granulysin isoforms have major implications for diagnosis and potential new therapies for human disease.  相似文献   
139.
Fe(II)-loaded pectin based hydrogels were used to remove As(V) from water. The hydrogels were synthesized by crosslinking pectin 'as such' or in the presence of 2-acrylamido-2-methylpropanesulphonic acid and three crosslinkers. The hydrogels crosslinked with 5% glutaraldehyde showed the maximum uptake of both Fe(II) and As(V). The sorption of As(V) was found to be sensitive to pH and temperature changes, as the maximum sorption was observed at 35 degrees C and 7.0-9.2 pH.  相似文献   
140.
Although immigrants are a rapidly growing subgroup, little is known about overweight/obesity among the foreign-born in the United States, especially regarding the effect of age at arrival. This study determined whether overweight/obesity prevalence is associated with age at arrival of immigrants to the United States. We analyzed data on 6,421 adult immigrants from the New Immigrant Survey (NIS), a study that is nationally representative of adult immigrants with newly acquired legal permanent residence (LPR). Multiple regression analyses tested the effects of duration of residence and age at arrival on overweight/obesity, defined by BMI of > or = 25 kg/m(2), and self-reported dietary change score. We found the relationship between duration of residence and overweight/obesity prevalence varied by age at arrival (P < 0.001). Immigrants < or = 20-years old at arrival who had resided in the United States > or = 15 years were 11 times (95% confidence interval: 5.33, 22.56) more likely to be overweight/obese than immigrants < 20-years old at arrival who had resided in the United States < or = 1 year. By comparison, there was no difference in overweight/obesity prevalence by duration among immigrants who arrived at >50 years of age. Higher self-reported dietary change is also associated with overweight/obesity. In conclusion, immigrants younger than 20 at arrival in the United States may be at higher risk of overweight/obesity with increasing duration of residence than those who arrive at later ages. Obesity prevention among young US immigrants should be a priority.  相似文献   
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