Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.99.3 (PRE)
 1,923 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently, genome wide association studies showed that there is a strong association between abacavir-induced serious, idiosyncratic, adverse drug reactions (ADRs) and human leukocyte antigen-B*5701 (HLA-B*5701). Studies also found that abacavir-induced ADRs were seldom observed in patients carrying the HLA-B*5801 subtype. HLA-B*5801 of the same serotype (B17) as B*5701 differs by only 4 amino acids from B*5701. It is believed that because of these sequence differences, HLA-B*5801 cannot bind the specific peptides which are required for HLA-B*5701 to stimulate the T cell immune response. Thus, the difference in peptide binding profiles between HLA-B*5701 and B*5801 is an important clue for exploring the mechanisms of abacavir-induced ADRs. VHSE (principal component score vector of hydrophobic, steric, and electronic properties), a set of amino acid structural descriptors, was employed to establish QSAR models of peptide-binding affinities of HLA-B*5701 and B*5801. Optimal linear SVM (support vector machine) models with high predictive capabilities were obtained for both B*5701 and B*5801. The R(2) (coefficient of determination), Q(2) (cross-validated R(2)), and R(PRE)(2) (R(2) of test set) of two optimal models were 0.7530, 0.7037, 0.6153 (B*5701) and 0.6074, 0.5966, 0.5762 (B*5801), respectively. For B*5701 and B*5801, the mutations in positions 45 (MET-THR) and 46 (ALA-GLU) have little influence on the selection specificity of the P2 position of the bound peptide. However, the mutation in position 97 (VAL-ARG) greatly influences the selection specificity of the P7 position. HLA-B*5701 prefers the bulky and positively charged amino acids at the P7 position. In contrast, HLA-B*5801 prefers the non-polar hydrophobic amino acids at the P7 position while positively charged amino acids are unfavored.
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PMID:Peptide binding specificities of HLA-B*5701 and B*5801. 2301 31

There is a worldwide interest in how lockdown affects physical activity (PA) during the COVID-19 pandemic. Although it has been shown that the mandated stay-at-home restrictions and self-isolation measures applied in different countries were accosiated with a reduction in physical exercise and activity, such results derive from studying only specific periods of lockdown. However, in order for this hypothesis to be tested, consecutive lockdown periods need to be examined separately. In this study we focus on PA change in Greek adults over time, during each of the last four weeks of lockdown in Greece. The web-based Active-Q questionnaire (see Supplementary file 1_Active-Q) was used to collect data prior to the COVID-19 crisis (PRE condition) and during lockdown measures (POST condition). The period of data collection (5 April to 3 May 2020) was divided into four phases (Ph-I, Ph-II, Ph-III, Ph-V), corresponding to the 3rd, 4th, 5th and 6th lockdown week respectively (out of a six-week total lockdown). There were four independent groups of respondents (G-I, G-II, G-III, G-V) who reported their age, weight, height and usual PA habits. Energy expenditure (EE) was calculated (MET-min/week; see Supplementary file 2_Data) in four main different domains (daily occupation activities, means of transportation to and from daily occupation, leisure time and regular sporting activities; see Supplementary file 3_Corresponding MET values). Each group's dataset corresponded to one of the aforementioned phases (G-I to Ph-I, G-II to Ph-II, and so on). Overall PA change (from PRE to POST condition) ranged from -21.50% in G-I (Ph-I) to -5.03 in G-V (Ph-V); PA change in male subgroups ranged from -26.10% in Ph-I to -13.64 in Ph-V; in female subgroups it ranged from -17.42% in Ph-I to -1.39 in Ph-V. Although the decline in overall PA is evident in all groups during each lockdown phase (p<0.05), the combination of our data demonstrates that towards the end of lockdown this decline showed a gradual decreasing tendency.
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PMID:Evolution of changes in physical activity over lockdown time: Physical activity datasets of four independent adult sample groups corresponding to each of the last four of the six COVID-19 lockdown weeks in Greece. 3293 72