Coronary artery bypass surgery with arterial grafts in familial hypercholesterolemia

AbstractObjective: Familial hypercholesterolemia is a dominantly inherited disorder caused by mutations at the locus for the low-density lipoprotein receptor and is frequently associated with premature coronary artery disease. This study was performed to determine whether arterial grafting was associated with long-term benefits for patients with familial hypercholesterolemia. Methods: During the past 18 years, 101 patients with heterozygous familial hypercholesterolemia underwent primary coronary artery bypass grafting, with one hospital death. Group 1 patients (n = 31) received only saphenous vein grafts. Group 2A patients (n = 47) received one internal thoracic artery graft and supplemental vein grafts, and group 2B patients (n = 23) had multiple arterial grafts. After operation, all patients received diet therapy and intensive cholesterol-lowering drug therapy. Thirteen patients received low-density lipoprotein apheresis. Results: During a mean follow-up period of 95 months, 8 patients died, 9 underwent reoperation, and 12 received catheter intervention. The overall survival was 82% (95% confidence limits, 65%-97%) at 18 years after operation. The survival in group 2 was higher than that found in group 1 (P = .01). The overall freedom from major cardiac events (myocardial infarction, cardiac death, reoperation, and catheter intervention) was 57% (95% confidence limits, 40%-74%) at 16 years after operation. The freedom from reoperation in group 2 was higher than that found in group 1 (P = .03). There was no difference in the survival or freedom from major cardiac events between groups 2A and 2B. Conclusion: Arterial grafting improved the long-term freedom from reoperation in patients with familial hypercholesterolemia. Additional benefit of multiple arterial grafting could not be identified. (J Thorac Cardiovasc Surg 2000;119:1008-14

Inbreeding ratio and genetic relationships among strains of the Western clawed frog, Xenopus tropicalis

The Western clawed frog, Xenopus tropicalis, is a highly promising model amphibian, especially in developmental and physiological research, and as a tool for understanding disease. It was originally found in the West African rainforest belt, and was introduced to the research community in the 1990s. The major strains thus far known include the Nigerian and Ivory Coast strains. However, due to its short history as an experimental animal, the genetic relationship among the various strains has not yet been clarified, and establishment of inbred strains has not yet been achieved. Since 2003 the Institute for Amphibian Biology (IAB), Hiroshima University has maintained stocks of multiple X. tropicalis strains and conducted consecutive breeding as part of the National BioResource Project. In the present study we investigated the inbreeding ratio and genetic relationship of four inbred strains at IAB, as well as stocks from other institutions, using highly polymorphic microsatellite markers and mitochondrial haplotypes. Our results show successive reduction of heterozygosity in the genome of the IAB inbred strains. The Ivory Coast strains clearly differed from the Nigerian strains genetically, and three subgroups were identified within both the Nigerian and Ivory Coast strains. It is noteworthy that the Ivory Coast strains have an evolutionary divergent genetic background. Our results serve as a guide for the most effective use of X. tropicalis strains, and the long-term maintenance of multiple strains will contribute to further research efforts

Nature and Clinical Outcomes of Acute Hemorrhagic Rectal Ulcer

Acute hemorrhagic rectal ulcer (AHRU) is a relatively rare disease that can lead to massive hematochezia. Although AHRU is a potentially life-threatening disease, its characteristics and clinical course are not fully understood. In this study, the clinical features were compared between AHRU and lower gastrointestinal bleeding (LGIB) from other causes (non-AHRU). Then, risk factors for all-cause in-hospital mortality in patients with AHRU were identified. A total of 387 consecutive adult patients with LGIB who were managed at two tertiary academic hospitals in Akita prefecture in Japan were retrospectively enrolled. Subjects were divided into AHRU and non-AHRU groups according to the source of bleeding. Regression analyses were used to investigate significant associations, and the results were expressed as odds ratios (ORs) and 95% confidence intervals (CIs). AHRU was found as the bleeding source in 72 (18.6%) of the patients. In comparison to non-AHRU, having AHRU was significantly associated with in-hospital onset, age > 65 years, and systolic blood pressure < 90 mmHg. The AHRU group had a significantly higher in-hospital mortality rate in comparison to the non-AHRU group (18.0% vs. 8.3, p = 0.02), and hypoalbuminemia (<2.5 g/dL) was significantly associated with in-hospital mortality in the AHRU group (OR, 4.04; 95%CI, 1.11-14.9; p = 0.03). AHRU accounts for a substantial portion (18.6%) of LGIB in our area, where the aging rate is the highest in Japan. Since AHRU is a potentially life-threatening disease that requires urgent identification and management, further studies to identify robust risk factors associated with serious clinical outcomes are required

Usefulness of the CHAMPS score for risk stratification in lower gastrointestinal bleeding

We have recently developed a simple prediction score, the CHAMPS score, to predict in-hospital mortality in patients with upper gastrointestinal bleeding. In this study, the primary outcome of this study was the usefulness of the CHAMPS score for predicting in-hospital mortality with lower gastrointestinal bleeding (LGIB). Consecutive adult patients who were hospitalized with LGIB at two tertiary academic medical centers from 2015 to 2020 were retrospectively enrolled. The performance for predicting outcomes with CHAMPS score was assessed by a receiver operating characteristic curve analysis, and compared with four existing scores. In 387 patients enrolled in this study, 39 (10.1%) of whom died during the hospitalization. The CHAMPS score showed good performance in predicting in-hospital mortality in LGIB patients with an AUC (95% confidence interval) of 0.80 (0.73-0.87), which was significantly higher in comparison to the existing scores. The risk of in-hospital mortality as predicted by the CHAMPS score was shown: low risk (score = 4), 37.1%. The CHAMPS score is useful for predicting in-hospital mortality in patients with LGIB

近赤外光を利用した連続的心筋酸素飽和度測定による warm blood cardioplegia の検討

金沢大学医薬保健研究域医学系Continuous infusion of warm blood cardioplegic solution is often interrupted during coronary artery bypass grafting to obtain a bloodless operating field. We measured myocardial oxygen saturation continuously using near-infrared spectroscopy to determine myocardial oxygen metabolism during intermittent warm blood cardioplegia (IWBC). In 7 adult mongrel dogs undergoing cardiopulmonary bypass IWBC was administered using the Buckberg-Shiley system. Cardiac arrest was induced by a warm blood cardioplegic infusion of 100 ml/min for 5 minutes followed by a maintenance infusion of 40 ml/min for 5 minutes. The infusion of warm blood cardioplegia was then stopped for 15 minutes. Measurement of myocardial oxygen saturation was performed continuously throughout cardiopulmonary bypass. IWBC produced an increase in myocardial oxygen saturation for the first 5 minutes and a slight decrease for the second 5 minutes. After the termination of IWBC, myocardial oxygen saturation showed a marked reduction for 3 minutes and plateaued after 5 minutes. Measurement of myocardial oxygen saturation revealed myocardial oxygen metabolism during IWBC. This procedure may be a useful way to monitor myocardial oxygen metabolism during open heart surgery

Pseudouridine at position 55 in tRNA controls the contents of other modified nucleotides for low-temperature adaptation in the extreme-thermophilic eubacterium Thermus thermophilus

Pseudouridine at position 55 (Ψ55) in eubacterial tRNA is produced by TruB. To clarify the role of the Ψ55 modification, we constructed a truB gene disruptant (ΔtruB) strain of Thermus thermophilus which is an extreme-thermophilic eubacterium. Unexpectedly, the ΔtruB strain exhibited severe growth retardation at 50°C. We assumed that these phenomena might be caused by lack of RNA chaperone activity of TruB, which was previously hypothetically proposed by others. To confirm this idea, we replaced the truB gene in the genome with mutant genes, which express TruB proteins with very weak or no enzymatic activity. However the growth retardation at 50°C was not rescued by these mutant proteins. Nucleoside analysis revealed that Gm18, m5s2U54 and m1A58 in tRNA from the ΔtruB strain were abnormally increased. An in vitro assay using purified tRNA modification enzymes demonstrated that the Ψ55 modification has a negative effect on Gm18 formation by TrmH. These experimental results show that the Ψ55 modification is required for low-temperature adaptation to control other modified. 35S-Met incorporation analysis showed that the protein synthesis activity of the ΔtruB strain was inferior to that of the wild-type strain and that the cold-shock proteins were absence in the ΔtruB cells at 50°C