Genetic variations and haplotype structures of the ABC transporter gene ABCC1 in a Japanese population

Multidrug resistance-related protein 1 (MRP1), an ATP-binding cassette transporter encoded by the ABCC1 gene, is expressed in many tissues, and functions as an efflux transporter for glutathione-, glucuronate- and sulfate-conjugates as well as unconjugated substrates. In this study, the 31 exons and their flanking introns of ABCC1 were comprehensively screened for genetic variations in 153 Japanese subjects to elucidate the linkage disequilibrium (LD) profiles and haplotype structures of ABCC1 that is necessary for pharmacogenetic studies of the substrate drugs. Eighty-six genetic variations including 31 novel ones were found: 1 in the 5'-flanking region, 1 in the 5'-untranslated region (UTR), 20 in the coding exons (9 synonymous and 11 nonsynonymous variations), 4 in the 3'-UTR, and 60 in the introns. Of these, eight novel nonsynonymous variations, 726G>T (Trp242Cys), 1199T>C (Ile400Thr), 1967G>C (Ser656Thr), 2530G>A (Gly844Ser), 3490G>A (Val1164Ile), 3550G>A (Glu1184Lys), 3901C>T (Arg1301Cys), and 4502A>G (Asp1501Gly), were detected with an allele frequency of 0.003. Based on the LD profiles, the analyzed regions of the gene were divided into five LD blocks (Blocks -1 and 1 to 4). The multiallelic repeat polymorphism in the 5'-UTR was defined as Block -1. For Blocks 1, 2, 3 and 4, 32, 23, 23 and 13 haplotypes were inferred, and 9, 7, 7 and 6 haplotypes commonly found on > or = 10 chromosomes accounted for > or = 91% of the inferred haplotypes in each block. Haplotype-tagging single nucleotide polymorphisms for each block were identified to capture the common haplotypes. This study would provide fundamental and useful information for the pharmacogenetic studies of MRP1-dependently effluxed drugs in Japanese.     

Fulminant Respiratory Failure Caused by Anti-asparaginyl tRNA Synthetase (Anti-KS) Antibody Syndrome-related Interstitial Lung Disease

Anti-asparaginyl transfer RNA (tRNA) synthetase (KS) antibodies, detected in <5% patients with anti-aminoacyl-tRNA synthetase antibody syndrome, are strongly associated with interstitial pneumonia but not myositis and skin symptoms. A recent report suggested that most patients with interstitial pneumonia and anti-KS antibody (KS-ILD) may present with chronic disease. We herein report a rare case of severe acute respiratory failure in a KS-ILD patient requiring extracorporeal membrane oxygenation (ECMO). ECMO is useful for facilitating not only lung rest until recovery but also the definitive diagnosis and treatment of ILD. KS-ILD can develop acutely with fulminant respiratory failure, as observed in this case.     

Effects of workplace measures against COVID-19 on psychological distress of full-time employees: A 12-month prospective study in the COVID-19 pandemic

ObjectiveThis study aimed to investigate the prospective effects of corporate and organizational workplace measures against COVID-19 on reducing employees’ psychological distress during a 12-month follow-up in the COVID-19 pandemic.MethodsData were retrieved from an online longitudinal panel survey of full-time employees in Japan, with the 1^st survey in March 2020, and the 2^nd to 6^th surveys in May, August, November 2020, February and March 2021, respectively. Seven area-specific workplace measures were assessed using a self-report 23-item scale at the 2^nd follow-up. Psychological distress was measured using an 18-item scale of the Brief Job Stress Questionnaire at each survey. Linear regressions and mixed model analysis were conducted of psychological distress at follow-ups on scores of the area-specific workplace measures, adjusting for psychological distress and other covariates at the 1^st survey.ResultsA total of 941 employees responded at baseline; most of them (86.9–90.9%) participated in the follow-up surveys. Linear regression analysis indicated that workplace measures of facilitating employees’ preventive measures (ie, hygiene behaviors) statistically significantly and negatively correlated with psychological distress at the 5^th survey [b=-0.518, standard error (SE) 0.259, P=0.046]. A statistically significant and negative interaction between the scores and time of follow-up was observed in the mixed model analysis (b=-0.096, SE 0.047, P=0.041). No such correlation or interaction was found for any of other subcategorical workplace measures.ConclusionsThe study provides prospective evidence for a protective effect of workplace measures to facilitate employee’s hygiene behaviors on reducing psychological distress of full-time employees in the COVID-19 pandemic. The association seems stronger at a later follow-up.     

Effects of intra- and extrahepatic portal systemic shunts on insulin metabolism

To study the effects of intra- and extrahepatic portal-systemic shunts on insulin degradation, 11 patients with liver cirrhosis and 7 noncirrhotic patients with liver disease were studied with percutaneous transhepatic catheterization. Insulin levels in portal and peripheral blood were measured simultaneously for 1-2 hr after intravenous administration of glucose. The degrees of intra- and extrahepatic portal-systemic shunting were measured with this technique using 131I-macroaggregated albumin and 99mTc-macroaggregated albumin. The amount of insulin secreted and insulin degraded were assessed from the areas under blood concentration curves for portal and peripheral blood. Insulin degradation was significantly reduced in cirrhotics compared to noncirrhotics with liver disease, although there was no difference in the amount of insulin secreted between these two groups. It was also correlated significantly with the degree of intrahepatic shunting but not with the degree of extrahepatic shunting. These results suggest that intrahepatic shunting plays an important role in the reduction of insulin degradation in cirrhosis.     

Thromboxane A2 modulates interaction of dendritic cells and T cells and regulates acquired immunity

Physical interaction of T cells and dendritic cells (DCs) is essential for T cell proliferation and differentiation, but it has been unclear how this interaction is regulated physiologically. Here we show that DCs produce thromboxane A2 (TXA2), whereas naive T cells express the thromboxane receptor (TP). In vitro, a TP agonist enhances random cell movement (chemokinesis) of naive but not memory T cells, impairs DC-T cell adhesion, and inhibits DC-dependent proliferation of T cells. In vivo, immune responses to foreign antigens are enhanced in TP-deficient mice, which also develop marked lymphadenopathy with age. Similar immune responses were seen in wild-type mice treated with a TP antagonist during the sensitization period. Thus, TXA2-TP signaling modulates acquired immunity by negatively regulating DC-T cell interactions.     

Hydrogen embrittlement of Ni-Ti superelastic alloy in fluoride solution

Hydrogen embrittlement of Ni-Ti superelastic alloy in a fluoride solution (0.2% APF) has been investigated by means of a tensile test (after immersion) and hydrogen thermal desorption analysis. Upon immersion, the tensile strength of the alloy decreased to the critical stress level of martensite transformation. Hydrogen desorption of the immersed specimens appeared with a peak at around 500 degrees C. The amount of absorbed hydrogen in the alloy ranged from 100 to 1000 mass ppm when immersed in the fluoride solution for 2 to 24 h. The immersion in the fluoride solution led to the degradation of mechanical properties due to hydrogen embrittlement. The results of the present study imply that one reason that Ti and its alloys fracture in the oral cavity is the fact that hydrogen is absorbed in a fluoride solution, such as prophylactic agents.     

Regulation of phospholipase A2 in human leukemia cell lines: its implication for intracellular signaling.

Permeabilized human leukemia HL-60 and U-937 cells suspended in an acidic or alkaline medium release various unsaturated fatty acids, most abundantly oleic and arachidonic acids. Concomitant production of lysophospholipids suggests that phospholipases A2 play a major role in this fatty acid release reaction. The fatty acid release at acidic conditions depends on the intracellular Ca2+ concentrations at the 10(-8)-10(-7) M range and is enhanced by membrane-permeant diacylglycerols, although this enhancement seems independent of protein kinase C activation. On the other hand, the fatty acid release at alkaline conditions is potentiated by vanadate, and this potentiation is counteracted by genistein, suggesting a role of tyrosine phosphorylation in this release reaction. GTP[gamma S], an activator of G proteins, greatly enhances the fatty acid release. Aluminum fluoride, another activator of heterotrimeric G proteins, also greatly potentiates this release reaction. Phorbol ester increases the fatty acid release at alkaline conditions, to some extent, whereas it counteracts the vanadate-induced potentiation of fatty acid release. The results imply that several phospholipases A2 are coupled to receptors for their activation, thereby functioning in the transmembrane control of cellular events.