ABCC6

Purpose. To report the spectrum of ABCC6 variants in Japanese patients with angioid streaks (AS). Patients and Methods. This was a single-center cohort study. The medical records of 20 patients with AS from 18 unrelated Japanese families were retrospectively reviewed. Screening of the ABCC6 gene (exons 1 to 31) was performed using PCR-based Sanger sequencing. Results. Eight ABCC6 variants were identified as candidate disease-causing variants. These eight variants included five known variants (p.Q378X, p.R419Q, p.V848CfsX83, p.R1114C, and p.R1357W), one previously reported variant (p.N428S) of unknown significance, and two novel variants (c.1939C>T [p.H647Y] and c.3374C>T [p.S1125F]); the three latter variants were determined to be variants of significance. The following four variants were frequently identified: p.V848CfsX83 (14/40 alleles, 35.0%), p.Q378X (7/40 alleles, 17.5%), p.R1357W (6/40 alleles, 15.0%), and p.R419Q (4/40 alleles, 10.0%). The ABCC6 variants were identified in compound heterozygous or homozygous states in 13 of 18 probands. Two families showed a pseudodominant inheritance pattern. Pseudoxanthoma elasticum was seen in 15 of 17 patients (88.2%) who underwent dermatological examination. Conclusions. We identified disease-causing ABCC6 variants that were in homozygous or compound heterozygous states in 13 of 18 families (72.2%). Our results indicated that ABCC6 variants play a significant role in patients with AS in the Japanese population

Enhancing effects of salicylate on tonic and phasic block of Na+ channels by class 1 antiarrhythmic agents in the ventricular myocytes and the guinea pig papillary muscle

AbstractObjective: To study the interaction between salicylate and class 1 antiarrhythmic agents. Methods: The effects of salicylate on class 1 antiarrhythmic agent-induced tonic and phasic block of the Na+ current (INa) of ventricular myocytes and the upstroke velocity of the action potential (Vmax) of papillary muscles were examined by both the patch clamp technique and conventional microelectrode techniques. Results: Salicylate enhanced quinidine-induced tonic and phasic block of INa at a holding potential of −100 mV but not at a holding potential of −140 mV; this enhancement was accompanied by a shift of the h∞ curve in the presence of quinidine in a further hyperpolarized direction, although salicylate alone did not affect INa. Salicylate enhanced the tonic and phasic block of Vmax induced by quinidine, aprindine and disopyramide but had little effect on that induced by procainamide or mexiletine; the enhancing effects were related to the liposolubility of the drugs. Conclusions: Salicylate enhanced tonic and phasic block of Na+ channels induced by class 1 highly liposoluble antiarrhythmic agents. Based on the modulated receptor hypothesis, it is probable that this enhancement was mediated by an increase in the affinity of Na+ channel blockers with high lipid solubility to the inactivated state channels

Change in body weight of mothers and neonates and in milk composition during denning period in captive Japanese black bears (Ursus thibetanus japonicus)

Japanese black bears, Ursus thibetanus japonicus, have been classified as a vulnerable species so that data on reproduction are needed to maintain and/or extend their population. They are known to have a peculiar style of reproduction, giving birth to their neonates and raising them during denning, a period of complete fasting. In this study, we investigated the metabolic rate and milk composition of mother bears raising neonates, and the changes in body weight of the neonates under captive conditions. Seven female bears kept in dens were weighed once a month, and the amount of energy they used was calculated. From birth, cubs were also weighed and their growth rate was determined. In addition, the milk composition was analyzed to investigate its characteristics. As a result, it was found that mother bears used 34% more energy than did solitary females. There was no significant difference in the energy used for nursing whether they had single or twin cubs. On the other hand, the body weight gain of single cubs was significantly higher than that of twin cubs, suggesting that the growth of the cubs was highly affected by the suppression of mother's energy consumption during the fasting period. The milk had high fat and low sugar concentrations. This indicates that mother bears used the fat accumulated prior to denning for their main energy source when raising cubs. Considering all results together, Japanese black bears showed remarkable efficiency in the use of energy for reproduction during the fasting period

Chemical characterization of milk oligosaccharides of the tiger quoll (Dasyurus maculatus), a marsupial

Milk oligosaccharides were separated from the carbohydrate fraction of milk of the tiger quoll a species of marsupial that is closely related to the eastern quoll, Dasyurus viverrinus. They were characterized by H-1 - nuclear magnetic resonance spectroscopy and matrix - assisted laser desorption/ionization time-of-flight mass spectrometry. The following oligosaccharides were identified; Gal(beta 1-3) Gal(beta 1-4) Glc, Gal(beta 1-3) Gal(beta 1-3) Gal(beta 1-4) Glc, Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc, Gal(beta 1-3) Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc, Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3) Gal(beta 1-4) Glc, Gal(beta 1-3)[Gal(beta 1-3) Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc, Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc, Neu5Ac(alpha 2-3) Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc, Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc with an alpha(2-3) Neu5Ac linked to beta(1-4) Gal residue of either branch of Gal(beta 1-4) GlcNAc(beta 1-6) units, and Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc with a beta(1-3) linked Gal and an alpha(2-3) linked Neu5Ac. In addition, larger oligosaccharides were characterized as follows; Gal(beta 1-3){Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) GlcNAc(beta 1-6)} Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-4) Glc and Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 1-6)] Gal(beta 1-3){Gal(beta 1-3)[Gal(beta 1-4) GlcNAc(beta 16)] Gal(beta 1-4) GlcNAc(beta 1-6)} Gal(beta 1-4) Glc and their alpha(2-3) linked Neu5Ac derivatives