A preliminary prediction model using a deep learning software program for prolonged hospitalization after cardiovascular surgery.

A prolonged length of hospital stay (LOS) has become an important issue among patients undergoing cardiovascular surgery in our aging society. However, there are no established prediction models for a prolonged LOS. We therefore created a prediction model of a prolonged LOS using a deep learning software program (Prediction One; Sony Network Communications Inc., Tokyo, Japan) using preoperative data. Subjects were 157 patients (121 for training data, 36 for validation data). A prolonged LOS was defined as a more than 30-day postoperative stay due to physical inactivity. The area under the receiver operating characteristic curve and the accuracy of the model in the validation data were 0.806 and 67%, respectively. In conclusion, the preliminary model demonstrated acceptable performance for the prediction of a prolonged LOS after cardiovascular surgery.

Cardioprotective effects of chloroquine pretreatment on ischemic and reperfusion injury via activation of ERK1/2 in isolated rat hearts.

PURPOSE: Several therapeutic agents have been found to prevent myocardial ischemic and reperfusion (I/R) injury after cardiac surgery; however, no drug is routinely used to afford cardioprotective benefits in clinical settings. Herein, we aimed to determine whether chloroquine (CQ) pretreatment attenuates I/R injury after global ischemia in isolated rat hearts and elucidate mechanisms underlying the effects of CQ. METHODS: Isolated rat hearts were subjected to 30-min global ischemia, followed by 60-min reperfusion with Krebs-Henseleit buffer (KHB). Immediately before ischemia, 10 mL of pretreatment solutions (KHB, n = 4 or KHB + CQ [100 µM], n = 4) were injected through the aortic root. Cardiac function was examined based on the rate pressure product (RPP). Myocardial apoptosis was evaluated using TUNEL staining. To assess the reperfusion ischemia salvage kinase pathway, protein expression levels of AKT and extracellular signal-regulated kinase (ERK1/2) were determined using western blotting. To investigate the role of ERK1/2, an ERK1/2 selective inhibitor was used in eight additional rats. RESULTS: The recovery rate of the RPP was higher in the KHB + CQ group than in the KHB group 60 min after I/R (KHB, 44 ± 3% vs. KHB + CQ, 69 ± 7%; P = 0.019, d = 2.2). CQ pretreatment reduced apoptosis and enhanced the phosphorylation of ERK1/2; however, AKT phosphorylation was unaltered. In addition, the ERK1/2 inhibitor abolished CQ-mediated cardioprotective effects. CONCLUSIONS: CQ pretreatment showed protective effects on cardiac function after I/R by activating ERK1/2.

Screening, gene cloning, and characterization of orsellinic acid decarboxylase from Arthrobacter sp. K8 for regio-selective carboxylation of resorcinol derivatives.

Toward a sustainable synthesis of value-added chemicals, the method of CO2 utilization attracts great interest in chemical process engineering. Biotechnological CO2 fixation is a promising technology; however, efficient methods that can fix carbon dioxide are still limited. Instead, some parts of microbial decarboxylases allow the introduction of carboxy group into phenolic compounds using bicarbonate ion as a C1 building block. Here, we identified a unique decarboxylase from Arthrobacter sp. K8 that acts on resorcinol derivatives. A high-throughput colorimetric decarboxylase assay facilitated gene cloning of orsellinic acid decarboxylase from genomic DNA library of strain K8. Sequence analysis revealed that the orsellinic acid decarboxylase belonged to amidohydrolase 2 family, but shared low amino acid sequence identity with those of related decarboxylases. Enzymatic characterization unveiled that the decarboxylase introduces a carboxy group in a highly regio-selective manner. We applied the decarboxylase to enzymatic carboxylation of resorcinol derivatives. Using Escherichia coli expressing the decarboxylase gene as a whole cell biocatalyst, orsellinic acid, 2,4-dihydroxybenzoic acid, and 4-methoxysalicylic acid were produced in the presence of saturated bicarbonate. These findings could provide new insights into the production of useful phenolic acids from resorcinol derivatives.

A surgical case of aortic stenosis with recurrent gastrointestinal bleeding: Heyde syndrome.

INTRODUCTION: The combination of aortic stenosis, acquired coagulopathy, and anemia due to gastrointestinal (GI) bleeding is described as Heyde syndrome. PRESENTATION OF CASE: We report a surgical case of a 77-year-old man who was admitted because of melena and exertional chest compression. GI endoscopy could not reveal the origin of the GI bleeding. Conservative therapy including fasting and transfusion improved the anemia. Echocardiography demonstrated severe aortic stenosis (AS) with a hypertrophied left ventricle. Hematologic examination by gel electrophoresis showed deficiency of high-molecular-weight multimers of von Willebrand factor (vWF), resulting in the diagnosis of Heyde syndrome. He electively underwent aortic valve replacement (AVR) with a bioprosthesis using standard cardiopulmonary bypass. In the perioperative period, the patient had no recurrent anemia. He was discharged without subjective symptoms on postoperative day 18. The 20-month follow-up was unremarkable, with no episode of recurrent GI bleeding. DISCUSSION: Heyde syndrome is associated with acquired von Willebrand disease type IIA and AS. The true characteristic of von Willebrand disease type IIA is hemorrhagic diathesis caused by deficiency of high-molecular-weight multimers of vWF. Under the influence of high shear stress caused by AS, vWF is stretched and easily cleaved by vWF-cleaving protease. Consequently, it causes deficiency of high-molecular-weight multimers of vWF and primary hemostasis impairment. Therefore, the most effective treatment for Heyde syndrome is correction of AS. AVR can improve not only the hemodynamic status but also coagulopathy. CONCLUSION: The differential diagnosis of patients with recurrent GI bleeding with concurrent systolic murmur should include Heyde syndrome.

Enhanced Bacterial Growth and Gene Expression of D-Amino Acid Dehydrogenase With D-Glutamate as the Sole Carbon Source.

In a search for life-supporting, not life-assisting, D-amino acid metabolism, an environmental strain that grows better with D-glutamate as the sole carbon source was isolated from an ordinary river. The strain, designated as A25, exhibited a faster growth rate and greater cell yield with D-glutamate than with L-glutamate. Conversely, the D/L ratio of total cellular glutamate was as low as 4/96, which suggests that D-glutamate is more likely catabolized than anabolized. Strain A25 was phylogenetically most closely related to the gamma-proteobacterial species Raoultella ornithinolytica, with a 16S rRNA gene sequence similarity of 100%. A standard strain, R. ornithinolytica JCM 6096T, also showed similarly enhanced growth with D-glutamate, which was proven for the first time. Gene expression of the enzymes involved in D-amino acid metabolism was assayed by reverse-transcription quantitative PCR (RT-qPCR) using specifically designed primers. The targets were the genes encoding D-amino acid dehydrogenase (DAD; EC 1.4.99.1), glutamate racemase (EC 5.1.1.3), D-glutamate oxidase (EC 1.4.3.7 or EC 1.4.3.15), and UDP-N-acetyl-α-D-muramoyl-L-alanyl-D-glutamate ligase (EC 6.3.2.9). As a result, the growth of strains A25 and R. ornithinolytica JCM 6096T on D-glutamate was conspicuously associated with the enhanced expression of the DAD gene (dadA) in the exponential phase compared with the other enzyme genes. Pseudomonas aeruginosa is also known to grow on D-glutamate as the sole carbon source but to a lesser degree than with L-glutamate. A standard strain of P. aeruginosa, JCM 5962T, was tested for gene expression of the relevant enzymes by RT-qPCR and also showed enhanced dadA expression, but in the stationary phase. Reduction of ferricyanide with D-glutamate was detected in cell extracts of the tested strains, implying probable involvement of DAD in the D-glutamate catabolizing activity. DAD-mediated catalysis may have advantages in the one-step production of α-keto acids and non-production of H2O2 over other enzymes such as racemase and D-amino acid oxidase. The physiological and biochemical importance of DAD in D-amino acid metabolism is discussed.