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Background: Treatment via a peripherally inserted central venous catheter is important for anticancer treatment, perioperative management, and nutrition management. In this study, we aimed to investigate the usefulness of cyanoacrylate glue (CG) in managing peripherally inserted central venous catheters in adults., Methods: This retrospective cohort study enrolled 411 adults requiring a central venous catheter for treatment in the Chiba University Esophageal-Gastro-Intestinal Surgery department between January 2021 and October 2022. The preventive effect of CG in reducing adverse events, including infection, tip migration, and thrombus formation, was evaluated by reviewing electronic medical records, chest radiographs, and contrast-enhanced computed tomography scans., Results: CG and other dressings were used in 158 (CG group) and 253 (control group) patients, respectively. The incidence of catheter infection based on the clinical course was lower in the CG group (3.2%) than in the control group (9.1%; P = 0.03). However, cases of infection confirmed by blood or catheter cultures did not differ between the CG (1.3%) and control (1.9%) groups (P = 1.0). Chest radiographs revealed that catheter tip migration (mean ± SD) was lesser in the CG group (8.2 ± 6.7 mm) than in the control group (15.0 ± 15.8 mm; P < 0.01). There were two cases of venous thrombus formation in the control group., Conclusion: In a population dominated by esophago-gastroenterological malignancy, peripherally inserted central catheter securement via CG was associated with decreased catheter removal because of suspected catheter infection. Further research on larger cohorts is needed to determine if other adverse events decrease following peripherally inserted central catheter securement via CG., (© 2024 The Authors. Journal of Parenteral and Enteral Nutrition published by Wiley Periodicals LLC on behalf of American Society for Parenteral and Enteral Nutrition.)

Background: Cardiomyocytes derived from human iPS cells (hiPSCs) include cells showing SAN- and non-SAN-type spontaneous APs., Objectives: To examine whether the deep learning technology could identify hiPSC-derived SAN-like cells showing SAN-type-APs by their shape., Methods: We acquired phase-contrast images for hiPSC-derived SHOX2/HCN4 double-positive SAN-like and non-SAN-like cells and made a VGG16-based CNN model to classify an input image as SAN-like or non-SAN-like cell, compared to human discriminability., Results: All parameter values such as accuracy, recall, specificity, and precision obtained from the trained CNN model were higher than those of human classification., Conclusions: Deep learning technology could identify hiPSC-derived SAN-like cells with considerable accuracy., Competing Interests: Authors declare no conflict of interests for this article., (© 2023 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of Japanese Heart Rhythm Society.)

Background: Pilsicainide, classified as a relatively selective Na + channel blocker, also has an inhibitory action on the rapidly-activating delayed-rectifier K + current ( I Kr ) through human ether-a-go-go-related gene (hERG) channels. We studied the effects of chronic exposure to pilsicainide on the expression of wild-type (WT) hERG proteins and WT-hERG channel currents, as well as on the expression of mutant hERG proteins, in a heterologous expression system., Methods: HEK293 cells stably expressing WT or mutant hERG proteins were subjected to Western blotting, immunofluorescence microscopy and patch-clamp experiments., Results: Acute exposure to pilsicainide at 0.03-10 μM influenced neither the expression of WT-hERG proteins nor WT-hERG channel currents. Chronic treatment with 0.03-10 μM pilsicainide for 48 h, however, increased the expression of WT-hERG proteins and channel currents in a concentration-dependent manner. Chronic treatment with 3 μM pilsicainide for 48 h delayed degradation of WT-hERG proteins and increased the channels expressed on the plasma membrane. A cell membrane-impermeant pilsicainide derivative did not influence the expression of WT-hERG, indicating that pilsicainide stabilized the protein inside the cell. Pilsicainide did not influence phosphorylation of Akt (protein kinase B) or expression of heat shock protein families such as HSF-1, hsp70 and hsp90. E4031, a chemical chaperone for hERG, abolished the pilsicainide effect on hERG. Chronic treatment with pilsicainide could also increase the protein expression of trafficking-defective mutant hERG, G601S and R752W., Conclusions: Pilsicainide penetrates the plasma membrane, stabilizes WT-hERG proteins by acting as a chemical chaperone, and enhances WT-hERG channel currents. This mechanism could also be applicable to modulations of certain mutant-hERG proteins.

Background: The human ether-a-go-go-related gene (HERG) encodes the α-subunit of rapidly activating delayed-rectifier potassium channels. Mutations in this gene cause long QT syndrome type 2 (LQT2). In most cases, mutations reduce the stability of the channel protein, which can be restored by heat shock (HS)., Methods: We identified the novel mutant A78T-HERG in a patient with LQT2. The purpose of the current study was to characterize this mutant protein and test whether HS and heat shock factors (HSFs) could stabilize the mutant protein. A78T-HERG and wild-type HERG (WT-HERG) were expressed in HEK293 cells and analyzed by immunoblotting, immunoprecipitation, immunofluorescence, and whole-cell patch clamping., Results: When expressed in HEK293 cells, WT-HERG gave rise to immature and mature forms of the protein at 135 and 155 kDa, respectively. A78T-HERG gave rise only to the immature form, which was heavily ubiquitinated. The proteasome inhibitor MG132 increased the expression of immature A78T-HERG and increased both the immature and mature forms of WT-HERG. WT-HERG, but not A78T-HERG, was expressed on the plasma membrane. In whole-cell patch clamping experiments, depolarizing pulses evoked E4031-sensitive HERG channel currents in cells transfected with WT-HERG, but not in cells transfected with A78T-HERG. The A78V mutant, but not A78G mutant, remained in the immature form similarly to A78T. Maturation of the A78T-HERG protein was facilitated by HS, expression of HSF-1, or exposure to geranyl geranyl acetone., Conclusions: A78T-HERG was characterized by protein instability and reduced expression on the plasma membrane. The stability of the mutant was partially restored by HSF-1, indicating that HSF-1 is a target for the treatment for LQT2 caused by the A78T mutation in HERG.

Background and Purpose: The expression of voltage-dependent K(+) channels (K(v) ) 1.5 is regulated by members of the heat shock protein (Hsp) family. We examined whether the heat shock transcription factor 1 (HSF-1) and its inducer geranylgeranylacetone (GGA) could affect the expression of K(v) 1.5 channels and its anchoring protein, synapse associated protein 97 (SAP97)., Experimental Approach: Transfected mouse atrial cardiomyocytes (HL-1 cells) and COS7 cells were subjected to luciferase reporter gene assay and whole-cell patch clamp. Protein and mRNA extracts were subjected to Western blot and quantitative real-time polymerase chain reaction., Key Results: Heat shock of HL-1 cells induced expression of Hsp70, HSF-1, SAP97 and K(v) 1.5 proteins. These effects were reproduced by wild-type HSF-1. Both heat shock and expression of HSF-1, but not the R71G mutant, increased the SAP97 mRNA level. Small interfering RNA (siRNA) against SAP97 abolished HSF-1-induced increase of K(v) 1.5 and SAP97 proteins. A luciferase reporter gene assay revealed that the SAP97 promoter region (from -919 to -740) that contains heat shock elements (HSEs) was required for this induction. Suppression of SIRT1 function either by nicotinamide or siRNA decreased the level of SAP97 mRNA. SIRT1 activation by resveratrol had opposing effects. A treatment of the cells with GGA increased the level of SAP97 mRNA, K(v) 1.5 proteins and I(Kur) current, which could be modified with either resveratrol or nicotinamide., Conclusions and Implications: HSF-1 induced transcription of SAP97 through SIRT1-dependent interaction with HSEs; the increase in SAP97 resulted in stabilization of K(v)1.5 channels. These effects were mimicked by GGA., (© 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.)

Objective: Our objective was to quantitate the contribution of the genetic polymorphism of the human MDR1 gene to the bioavailability and interaction profiles of digoxin, a substrate of P-glycoprotein., Methods: The pharmacokinetics of digoxin was studied in 15 healthy volunteers, who were divided into 3 groups (n = 5 each) on the basis of genotyping for the MDR1 gene, in a 4-dose study after single doses of digoxin alone (0.5 mg orally and intravenously) and coadministered with clarithromycin (400 mg orally for 8 days). The dose of digoxin was reduced during the clarithromycin phase (0.25 mg orally and intravenously)., Results: The bioavailability of digoxin in G/G2677C/C3435, G/T2677C/T3435, and T/T2677T/T3435 subjects were 67.6% +/- 4.3%, 80.9% +/- 8.9%, and 87.1% +/- 8.4%, respectively, and the difference between G/G2677C/C3435 and T/T2677T/T3435 subjects was statistically significant (P <.05). The MDR1 variants were also associated with differences in disposition kinetics of digoxin, with the renal clearance being almost 32% lower in T/T2677T/T3435 subjects (1.9 +/- 0.1 mL/min per kilogram) than G/G2677C/C3435 subjects (2.8 +/- 0.3 mL/min per kilogram), and G/T2677C/T3435 subjects having an intermediate value (2.1 +/- 0.6 mL/min per kilogram). Coadministration of clarithromycin did not consistently affect digoxin clearance or renal clearance. However, a significant increase in digoxin bioavailability was observed in G/G2677C/C3435 subjects (67.6% +/- 4.3% versus 85.4% +/- 6.1%; P <.05) but not in the other 2 genotype groups., Conclusion: The allelic variants in the human MDR1 gene are likely to be associated with altered absorption and/or disposition profiles of digoxin and P-glycoprotein-mediated drug interaction

Objectives: Increasing human and laboratory evidence suggests that post-resuscitative brain hypothermia reduces the pathologic consequences of brain ischemia. Using a swine model of prolonged cardiac arrest, this investigation sought to determine whether unilateral hypothermic carotid bypass was capable of inducing selective brain hypothermia and reducing neurohistologic damage., Methods: Ventricular fibrillation was induced in common swine (n = 12). After 20 minutes of cardiopulmonary arrest (without ventilatory support or cardiopulmonary resuscitation), systemic extracorporeal bypass was instituted to restore coronary and cerebral perfusion, followed by restoration of normal sinus rhythm. Animals randomized to the normal brain temperature (NBT) cohort received mechanical ventilation and intravenous fluids for 24 hours. The selective brain hypothermia (SBH) cohort received 12 hours of femoral/carotid bypass at 32 degrees C. The bypass temperature was then increased one degree per hour until reaching 37 degrees C and continued at this temperature until completion of the protocol (24 hours). Histopathologic damage was evaluated in two areas of the hippocampus., Results: Normal sinus rhythm was restored in all animals after the systemic (femoral/femoral) bypass was initiated. Nasal temperature (surrogate measure of brain temperature) remained higher than 37.0 degrees C throughout the 24-hour recovery period in the NBT animals. In the SBH cohort, right nasal temperature dropped to the mild hypothermic range (<34 degrees C) two hours after institution of femoral/carotid bypass. This was maintained throughout the 12-hour cooling period without hemodynamic compromise. There was a significant improvement in the neurohistology scores in the CA1 region of the hippocampus of the SBH treated animals as compared with those of the NBT cohort., Conclusions: Post-resuscitative selective brain hypothermia reduced regional ischemic brain damage in swine with prolonged ventricular fibrillation.

Objectives: Advances in the field of cardiopulmonary resuscitation have led to an increasing number of patients initially surviving sudden cardiac arrest. Unfortunately, most of these patients do not recover from the resultant anoxic brain insult. Several animal and human trials have suggested that post-resuscitative brain hypothermia may improve neurologic recovery after cardiopulmonary arrest. Present cooling methods are slow, induce only brain surface cooling, or result in systemic hypothermia. The authors tested the hypothesis that unilateral hypothermic carotid bypass would induce bilateral brain cooling without evoking systemic hypothermia or hemodynamic instability., Methods: Anesthetized, ventilated common swine (n = 6, 24-37 kg) underwent right femoral and carotid artery bypass cannulation. Central and peripheral hemodynamic parameters were recorded every 2 minutes throughout the procedure. Thermodynamic parameters included bilateral frontal lobe, bilateral nasopharyngeal, pulmonary artery, and rectal temperatures. Hypothermic femoral-carotid bypass was accomplished by drawing blood from the right femoral artery, cooling it to 24 degrees C, and returning it to the right carotid artery at a flow rate of 5 mL/kg/min for 30 minutes., Results: With initiation of cooling, brain temperatures dropped rapidly from baseline of 37.2 degrees C to 30.6 degrees C (right frontal lobe) and 33.1 degrees C (left frontal lobe) at 30 minutes. Pulmonary artery and rectal temperatures also decreased, but never reached mild hypothermic levels (34 degrees C). There was no significant change in any hemodynamic parameters during brain cooling., Conclusions: Femoral-carotid hypothermic bypass rapidly induced a state of selective brain hypothermia without causing systemic hypothermia or hemodynamic instability.

The aim of the present study was to clarify the therapeutic effects of 1alpha, 25[OH]2 vitamin D3 (calcitriol) pulse injection on bone lesions induced in a rat model of chronic cadmium toxicosis. Ovariectomized (OVX) and control-operated (sham-OVX) rats were given repeated intravenous injections of 0.5 mg/kg/day CdCl2 for 70 weeks. The rats were then treated intravenously with 0.02 microg/kg/day calcitriol 3 days per week for 8 weeks. CdCl2 treatment induced increases in osteoid volumes of the femur cortex and trabecula. This change was accompanied by an increase in the volume of iron deposition at the mineralization front of the trabeculae and a reduction in mineral density. Abnormalities of bone metabolic parameters, which were increases in the blood calcium, inorganic phosphorous, bone-specific alkaline phosphatase, parathyroid hormone (PTH) and osteocalcin levels, and in the urine deoxypyridinoline (D-PYR) level, were also induced. Calcitriol treatment increased the blood calcium and inorganic phosphorous levels, and reduced the blood PTH level. Decreases in blood tartrate-resistant acid phosphatase and urine d-PYR levels were also induced indicating that bone resorption was suppressed. The findings indicated that the increased osteoid volume of the cortex and Fe-deposition volume of the trabecula were improved. These effects or improvements were observed in the sham-OVX rats but not in the OVX rats.

1. Sodium current (INa) blockade by TYB-3823, a newly synthesized antiarrhythmic agent, was investigated in isolated single ventricular myocytes by use of the whole cell patch-clamp technique. 2. TYB-3823 blocked INa under steady-state conditions (Kd,rest = 500 microM, Kd,i = 4.9 microM), findings consistent with a shift in the steady state INa availability curve to more negative potentials. 3. TYB-3823 produced use-dependent block at 2 Hz in conjunction with increase in pulse duration (5-300 ms), that was markedly enhanced at less negative holding potentials. 4. The time course of the onset of block was accelerated and the degree of use-dependent block was decreased at more negative holding potential. The time course of the onset of block was accentuated with enhancing block at more positive holding potentials. 5. The time course of recovery from use-dependent block was accelerated at more negative holding potentials but was accentuated at more positive holding potentials. 6. These results suggest that both tonic block and use-dependent block of sodium channels in cardiac tissue might result from an interaction of TYB-3832 with sodium channels mainly in the inactivated channel states and the kinetics of the interaction between drug and receptor may be modulated by the inactivation gate.

One of the effects of antiarrhythmic drugs is the reduction of conduction velocity. Cable theory predicts that there is a nonlinear relationship between conduction velocity and upstroke velocity (Vmax) of action potential. By using conventional microelectrode techniques, aprindine-induced reduction of Vmax of action potential and conduction velocity in guinea-pig papillary muscles were measured. Aprindine-produced, use-dependent, and concentration-dependent changes in conduction velocity and the decline of square of conduction velocity was well fit by a single exponential. Time constants for square of conduction velocity were comparable to simultaneously measured time constants for effects of Vmax. At a concentration of 1 to 10 microM aprindine, onset changes between Vmax and conduction velocity had a log-linear relationship in a predicted fashion. Whereas, in the recovery process from aprindine-induced depression, slow recovery time course of conduction velocity was observed. In conclusion, in the presence of aprindine, only onset block of conduction velocity can be analyzed quantitatively in the relationship to observation on Vmax in vitro. These results suggested that in the presence of aprindine, the recovery of internal conductance may be slower than that of Vmax.