Histological validation of atrial structural remodelling in patients with atrial fibrillation.

BACKGROUND AND AIMS: This study aimed to histologically validate atrial structural remodelling associated with atrial fibrillation. METHODS AND RESULTS: Patients undergoing atrial fibrillation ablation and endomyocardial atrial biopsy were included (n = 230; 67 ± 12 years old; 69 women). Electroanatomic mapping was performed during right atrial pacing. Voltage at the biopsy site (Vbiopsy), global left atrial voltage (VGLA), and the proportion of points with fractionated electrograms defined as ≥5 deflections in each electrogram (%Fractionated EGM) were evaluated. SCZtotal was calculated as the total width of slow conduction zones, defined as regions with a conduction velocity of <30 cm/s. Histological factors potentially associated with electroanatomic characteristics were evaluated using multiple linear regression analyses. Ultrastructural features and immune cell infiltration were evaluated by electron microscopy and immunohistochemical staining in 33 and 60 patients, respectively. Fibrosis, intercellular space, myofibrillar loss, and myocardial nuclear density were significantly associated with Vbiopsy (P = .014, P < .001, P < .001, and P = .002, respectively) and VGLA (P = .010, P < .001, P = .001, and P < .001, respectively). The intercellular space was associated with the %Fractionated EGM (P = .001). Fibrosis, intercellular space, and myofibrillar loss were associated with SCZtotal (P = .028, P < .001, and P = .015, respectively). Electron microscopy confirmed plasma components and immature collagen fibrils in the increased intercellular space and myofilament lysis in cardiomyocytes, depending on myofibrillar loss. Among the histological factors, the severity of myofibrillar loss was associated with an increase in macrophage infiltration. CONCLUSION: Histological correlates of atrial structural remodelling were fibrosis, increased intercellular space, myofibrillar loss, and decreased nuclear density. Each histological component was defined using electron microscopy and immunohistochemistry studies.

Cutting-edge regenerative therapy for Hirschsprung disease and its allied disorders.

Hirschsprung disease (HSCR) and its associated disorders (AD-HSCR) often result in severe hypoperistalsis caused by enteric neuropathy, mesenchymopathy, and myopathy. Notably, HSCR involving the small intestine, isolated hypoganglionosis, chronic idiopathic intestinal pseudo-obstruction, and megacystis-microcolon-intestinal hypoperistalsis syndrome carry a poor prognosis. Ultimately, small-bowel transplantation (SBTx) is necessary for refractory cases, but it is highly invasive and outcomes are less than optimal, despite advances in surgical techniques and management. Thus, regenerative therapy has come to light as a potential form of treatment involving regeneration of the enteric nervous system, mesenchyme, and smooth muscle in affected areas. We review the cutting-edge regenerative therapeutic approaches for managing HSCR and AD-HSCR, including the use of enteric nervous system progenitor cells, embryonic stem cells, induced pluripotent stem cells, and mesenchymal stem cells as cell sources, the recipient intestine's microenvironment, and transplantation methods. Perspectives on the future of these treatments are also discussed.

The advantages of duct-to-duct biliary reconstruction in pediatric living donor liver transplantation.

BACKGROUND/PURPOSE: Whether Roux-en-Y hepatic jejunectomy (HJ) or duct-to-duct biliary reconstruction (DD) is more useful in pediatric living donor liver transplantation has not yet been fully investigated. Therefore, to assess the feasibility and safety of DD, we compared the surgical outcomes of DD to HJ. METHODS: We divided 45 patients, excluding those with biliary atresia, into the DD group (n = 20) and the HJ group (n = 25), according to the type of biliary reconstruction they received. RESULTS: The 5-year survival rates (DD vs. HJ = 79.7% vs. 83.6%, p = 0.70) and the incidence of biliary complications, including bile leakage and stricture (DD vs. HJ = 1 [5.0%] vs. 1 [4.0%], p = 0.87) were not significantly different between the groups. However, intestinal complications, including bowel perforation or ileus, were significantly common in the HJ group (9/25 [36.0%]) than in the DD group (1/20 [5.0%]; p = 0.01). The three patients in the HJ group with intestinal perforation all suffered perforation at the anastomosed site in the Roux-en-Y procedure. The subgroup analysis showed the non-inferiority of DD to HJ for biliary or intestinal complications in patients weighting < 10 kg. CONCLUSION: With a proper selection of cases, DD should be a safe method for biliary reconstruction in pediatric recipients with little risk of biliary complications equivalent to HJ and a reduced risk of intestinal complications.

Successful management to prevent early graft loss due to Seventh-day Syndrome after liver retransplantation: A case report and literature review.

Graft loss characterized by sudden deterioration after initial favorable recovery of the allograft function within the first week after liver transplantation was reported as "seventh-day syndrome." The outcome of seventh-day syndrome is extremely poor, and its etiology and management are not still established. We herein reported a seventh-day syndrome case who was successfully managed by immediate desensitization after liver retransplantation and reviewed by English literature. A 19-year-old woman who had underwent the first liver transplantation when she was 2-year-old. She developed graft failure due to chronic rejection and was on the waiting list for retransplantation. An evaluation of panel-reactive antibody showed high positivity, but there were no preformed donor-specific antibodies. Plasma exchange was performed one-time just before retransplantation and the mean fluorescence intensity significantly decreased. The second liver was successfully transplanted, and post-operative course was uneventful. However, on post-operative day 5, her body temperature elevated and thereafter, her liver enzymes dramatically elevated. We immediately started a desensitization consisted of plasma exchange, intravenous immunoglobulin, and anti-CD20 antibody. The peak level of AST and ALT was 5799 IU/L and 3960 IU/L, respectively. The pathological findings of liver biopsy revealed some central venous endotheliitis and massive centrilobular hemorrhagic hepatocellular necrosis. These findings were not typical for antibody-mediated rejection, but the desensitization was effective and liver graft was successfully rescued. The only way to prevent early graft loss due to seventh-day syndrome is thought to be an immediate decision to start intensive desensitization.

The experiences of interval appendectomy for inflammatory appendiceal mass.

BACKGROUND: Interval appendectomy (IA) is a common treatment of acute appendicitis (AA) with inflammatory appendiceal mass (IAM). However, the management of patients with IAM is still controversial. The aim of this study was to assess the outcomes in patients with this condition. METHODS: We retrospectively evaluated 244 patients with AA for their clinical characteristics and outcomes. RESULTS: Forty-three patients had IAM at the first medical examination. The mean age was significantly younger and the C-reactive protein level significantly higher (12.6 vs 3.1 mg/dL) in patients with IAM. Thirty-four patients received IA, and nine received emergency appendectomy (EA). In the IA group, the diameter of the abscess was larger than in the EA group (31.4 vs 16.1 mm). The total length of hospitalization was longer in the IA group than the EA group (20.6 vs 7.0 days), although the operative time was longer in the EA group because of adhesion (101.1 vs 192.1 min). Furthermore, most IA patients received a reduced-port appendectomy (74% vs 11%). Recurrence occurred in approximately 15% of patients awaiting IA. There were no complications in either group. CONCLUSIONS: Although each treatment approach has its advantages and disadvantages, both IA and EA can be the first option for the treatment of AA with IAM.

Impact of Renal Dysfunction on Left Atrial Structural Remodeling and Recurrence After Catheter Ablation for Atrial Fibrillation　- A Propensity Score Matching Analysis.

BACKGROUND: Renal dysfunction coexists with other known risk factors of left atrial (LA) structural remodeling, expressed as low-voltage zones (LVZs), and the recurrence of atrial fibrillation (AF) after ablation. This study aimed to determine whether renal dysfunction had an independent effect on the presence of LVZs and recurrence after AF ablation, using propensity score (PS) matching analysis.Methods and Results:448 consecutive patients who underwent their initial AF ablation were enrolled. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, with 126 (28%) patients having CKD. Using PS matching analysis, new subsets (CKD and non-CKD group, n=103 each) were obtained, matched for age, sex, AF type, and LA volume. The presence of LVZs defined as bipolar voltage <0.5 mV was higher in the CKD group than in the non-CKD group (31% vs. 17%, P=0.034). Multivariate analysis showed eGFR was an independent predictor of the presence of LVZs (odds ratio 1.31 per 10-mL/min/1.73 m2decrease, P=0.029). AF-free survival rate was significantly lower in the CKD patients during 20±9 months of follow-up (63% vs. 82%, P=0.019), and eGFR was shown to be an independent predictor of recurrence (hazard ratio 1.29 per 10-mL/min/1.73 m2decrease, P=0.006), but the presence of LVZs did not predict recurrence. CONCLUSIONS: Renal dysfunction independently predicted not only the recurrence of AF after ablation but also the presence of LVZs.

ß-hydroxybutyrate protects hepatocytes against endoplasmic reticulum stress in a sirtuin 1-independent manner.

ß-hydroxybutyrate (BHB), a major ketone body in mammals, is produced from fatty acids through mitochondrial fatty acid oxidation in hepatocytes. To elucidate the role of BHB in the hepatic endoplasmic reticulum (ER), we examined the effects of BHB on hepatic ER stress induced by tunicamycin. In mouse hepatoma Hepa1c1c7 cells, BHB treatment suppressed the protein expression of ER stress responsive genes and increased cell viability, while reducing the protein expression of apoptosis inducible genes, without causing any alterations in the protein expression of sirtuin 1 (SIRT1) or the phosphorylation of AMP-activated protein kinase. The intraperitoneal administration of BHB also reduced the protein expression of ER stress responsive genes in mouse livers. In human hepatoma HepG2 cells, the protein expression levels of ER stress responsive genes were increased by the partial inhibition of BHB production with siRNA targeting endogenous 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) lyase, whereas they were decreased by promoting BHB production with fenofibrate. These findings revealed that BHB helps to suppress hepatic ER stress via a SIRT1-independent pathway, and it might be possible to manipulate ER stress by regulating BHB production genetically or pharmacologically.

Adrenic acid as an inflammation enhancer in non-alcoholic fatty liver disease.

BACKGROUND: This study was designed to identify novel links between lipid species and disease progression in non-alcoholic fatty liver disease (NAFLD). METHODS: We analyzed lipid species in the liver and plasma of db/db mice fed a choline-deficient l-amino acid-defined, high-fat diet (CDAHFD) using liquid chromatography/mass spectrometry (LC/MS). An in vitro experiment was performed using HepG2 cells stimulated with recombinant human TNFα or IL1ß. The expression of steatosis-, inflammation-, and fibrosis-related genes were analyzed. Plasma samples from NAFLD patients were also analyzed by LC/MS. RESULTS: The CDAHFD-fed db/db mice with hepatic steatosis, inflammation, mild fibrosis, obesity, and hypercholesterolemia displayed significantly higher hepatic and plasma levels of free adrenic acid (p < 0.05). The accumulated adrenic acid in the CDAHFD-fed db/db mice was associated with increased expression of ELOVL2 and 5, and the suppression of the acyl-CoA oxidase 1 gene during peroxisomal ß-oxidation. The pretreatment of HepG2 cells with adrenic acid enhanced their cytokine-induced cytokines and chemokines mRNA expression. In NAFLD patients, the group with the highest ALT levels exhibited higher plasma adrenic acid concentrations than the other ALT groups (p-value for trend <0.001). CONCLUSION: Data obtained demonstrated that adrenic acid accumulation contributes to disease progression in NAFLD.

Targeted deletion of thioesterase superfamily member 1 promotes energy expenditure and protects against obesity and insulin resistance.

Mammalian acyl-CoA thioesterases (Acots) catalyze the hydrolysis of fatty acyl-CoAs to form free fatty acids plus CoA, but their metabolic functions remain undefined. Thioesterase superfamily member 1 (Them1; synonyms Acot11, StarD14, and brown fat inducible thioesterase) is a long-chain fatty acyl-CoA thioesterase that is highly expressed in brown adipose tissue and is regulated by both ambient temperature and food consumption. Here we show that Them1(-/-) mice were resistant to diet-induced obesity despite greater food consumption. Them1(-/-) mice exhibited increased O(2) consumption and heat production, which were accompanied by increased rates of fatty acid oxidation in brown adipose tissue and up-regulation of genes that promote energy expenditure. Them1(-/-) mice were also protected against diet-induced inflammation in white adipose tissue, as well as hepatic steatosis, and demonstrated improved glucose homeostasis. The absence of Them1 expression in vivo and in cell culture led to markedly attenuated diet- or chemically induced endoplasmic reticulum stress responses, providing a mechanism by which Them1 deficiency protects against insulin resistance and lipid deposition. Taken together, these data suggest that Them1 functions to decrease energy consumption and conserve calories. In the setting of nutritional excess, the overproduction of free fatty acids by Them1 provokes insulin resistance that is associated with inflammation and endoplasmic reticulum stress.

Thioesterase superfamily member 2/Acyl-CoA thioesterase 13 (Them2/Acot13) regulates adaptive thermogenesis in mice.

Members of the acyl-CoA thioesterase (Acot) gene family hydrolyze fatty acyl-CoAs, but their biological functions remain incompletely understood. Thioesterase superfamily member 2 (Them2; synonym Acot13) is enriched in oxidative tissues, associated with mitochondria, and relatively specific for long chain fatty acyl-CoA substrates. Using Them2(-/-) mice, we have demonstrated key roles for Them2 in regulating hepatic glucose and lipid metabolism. However, reduced body weights and decreased adiposity in Them2(-/-) mice observed despite increased food consumption were not well explained. To explore a role in thermogenesis, mice were exposed to ambient temperatures ranging from thermoneutrality (30 °C) to cold (4 °C). In response to short term (24-h) exposures to decreasing ambient temperatures, Them2(-/-) mice exhibited increased adaptive responses in physical activity, food consumption, and energy expenditure when compared with Them2(+/+) mice. By contrast, genotype-dependent differences were not observed in mice that were equilibrated (96 h) at each ambient temperature. In brown adipose tissue, the absence of Them2 was associated with reduced lipid droplets, alterations in the ultrastructure of mitochondria, and increased expression of thermogenic genes. Indicative of a direct regulatory role for Them2 in heat production, cultured primary brown adipocytes from Them2(-/-) mice exhibited increased norepinephrine-mediated triglyceride hydrolysis and increased rates of O2 consumption, together with elevated expression of thermogenic genes. At least in part by regulating intracellular fatty acid channeling, Them2 functions in brown adipose tissue to suppress adaptive increases in energy expenditure.

Metabolomics-based search for therapeutic agents for non-alcoholic steatohepatitis.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the commonest form of chronic liver disease in developed countries. Non-alcoholic steatohepatitis (NASH), which represents advanced stage NAFLD, is increasingly being recognized as a major cause of liver-related morbidity and mortality. However, no effective drugs against NASH have yet been developed. Therefore, we searched for candidate therapeutic agents based on the changes in levels of hepatic metabolites via gas chromatography mass spectrometry (GC/MS)-based metabolome analysis of livers from methionine-choline deficient (MCD) diet-fed mice, a mouse model of NASH. METHODS: The metabolites were extracted from the livers of the MCD diet-fed mice and then analyzed using GC/MS. Subsequently, the MCD diet-fed mice were supplemented with hypotaurine, and the therapeutic effects of hypotaurine against steatohepatitis were evaluated. RESULTS: Ninety-nine metabolites were detected in the livers of the MCD diet-induced steatohepatitis model mice. Among these metabolites, hypotaurine exhibited the greatest decrease in its concentration in the mice. Supplementation with 2 mmol/kgBW hypotaurine attenuated liver injuries and fat accumulation caused by the MCD diet-induced steatohepatitis. Furthermore, 10 mmol/kgBW hypotaurine supplementation ameliorated fibrosis and oxidative stress induced by the MCD diet. CONCLUSION: The present metabolome analysis-based study demonstrated that hypotaurine is a novel candidate therapeutic agent for NASH.

Thioesterase superfamily member 2/acyl-CoA thioesterase 13 (Them2/Acot13) regulates hepatic lipid and glucose metabolism.

Members of the acyl-CoA thioesterase (Acot) gene family catalyze the hydrolysis of fatty acyl-CoAs, but their biological functions remain unknown. Thioesterase superfamily member 2 (Them2; synonym Acot13) is a broadly expressed mitochondria-associated Acot. Them2 was previously identified as an interacting protein of phosphatidylcholine transfer protein (PC-TP). Pctp(-/-) mice exhibit altered fatty acid metabolism that is accompanied by reduced hepatic glucose production. To examine the role of Them2 in regulating hepatic lipid and glucose homeostasis, we generated Them2(-/-) mice. In livers of Them2(-/-) mice compared with Them2(+/+) controls, a 1.9-fold increase in the K(m) of mitochondrial thioesterase activity was accompanied by a 28% increase in fatty acyl-CoA concentration. A reciprocal 23% decrease in free fatty acid concentration was associated with reduced activation of peroxisome proliferator-activated receptor α. However, fatty acid oxidation rates were preserved in livers of Them2(-/-) mice, suggesting that Them2 functions to limit ß-oxidation. Hepatic glucose production was also decreased by 45% in the setting of reduced hepatocyte nuclear factor 4α (HNF4α) expression. When fed a high-fat diet, Them2(-/-) mice were resistant to increases in hepatic glucose production and steatosis. These findings reveal key roles for Them2 in the regulation of hepatic metabolism, which are potentially mediated by PC-TP-Them2 interactions.

The Factors Associated with the Selection of Early Excision Surgery for Congenital Biliary Dilatation with a Prenatal Diagnosis.

PURPOSE: The aim of this study was to clarify the appropriate management after birth for congenital biliary dilatation (CBD, choledochal cyst) patients with a prenatal diagnosis. METHOD: Thirteen patients with a prenatal diagnosis of CBD who underwent liver biopsy during excision surgery were divided into two groups and retrospectively analyzed: group A, with liver fibrosis above F1 and group B, without liver fibrosis. RESULTS: Excision surgery was performed earlier in group A (F1-F2), at a median of 106 days old (p = 0.04). There were significant differences between the two groups in the presence symptoms and sludge, the cyst size, and the level of serum bilirubin and gamma glutamyl transpeptidase (GGT) before excision surgery (p < 0.05). Especially, in group A, prolonged serum GGT elevation and larger cysts were consistently observed from birth. The cut-off values of predictions for the presence of liver fibrosis in serum GGT and cyst size were 319 U/l and 45 mm. No significant differences were observed in the postoperative liver function or complications during the follow-up period. CONCLUSION: In patients with prenatally diagnosed CBD, the postnatal serial changes of serum GGT values and cyst size, in addition to symptoms, could help to prevent progressive liver fibrosis. LEVEL OF EVIDENCE: Ⅲ. TYPE OF STUDY: Treatment Study.

Fabrication of High-Resolution Fine Microneedles Derived from Hydrolyzed Hyaluronic Acid Gels in Vacuum Environment Imprinting Using Water Permeable Mold.

Hydrolyzed hyaluronic acid high-resolution fine microneedles of 13 µm in diameter and 24 µm in height were fabricated from hydrolyzed hyaluronic acid gels made in mixtures of water using vacuum environment imprint lithography processes with a water permeable mold. The gas traps of water and volatile solvents in the imprint materials cause transfer failure in the conventional water impermeable molds of quartz and metal. However, the water permeable mold allows the use of 67 wt% dilution water with high solubility to increase the fluidity of the hydrolyzed hyaluronic acid during the patterning of high-resolution fine microneedles for cosmetics and pharmaceuticals. This demonstration sets a new paradigm of functional pure gels for high-resolution nano-patterning applications with various cosmetic and pharmaceutical materials containing dilution water using a water permeable mold.

Atrial Structural Remodeling in Patients With Atrial Fibrillation Is a Diffuse Fibrotic Process: Evidence From High-Density Voltage Mapping and Atrial Biopsy.

Background Low-voltage areas (LVAs) in the atria of patients with atrial fibrillation are considered local fibrosis. We hypothesized that voltage reduction in the atria is a diffuse process associated with fibrosis and that the presence of LVAs reflects a global voltage reduction. Methods and Results We examined 140 patients with atrial fibrillation and 13 patients with a left accessory pathway (controls). High-density bipolar voltage mapping was performed using a grid-mapping catheter during high right atrial pacing. Global left atrial (LA) voltage (VGLA) in the whole LA and regional LA voltage (VRLA) in 6 anatomic regions were evaluated with the mean of the highest voltage at a sampling density of 1 cm2. Patients with atrial fibrillation were categorized into quartiles by VGLA. LVAs were evaluated at voltage cutoffs of 0.1, 0.5, 1.0, and 1.5 mV. Twenty-eight patients with atrial fibrillation also underwent right atrial septum biopsy, and the fibrosis extent was quantified. Voltage at the biopsy site (Vbiopsy) was recorded. VGLA results by category were Q1 (<4.2 mV), Q2 (4.2-5.6 mV), Q3 (5.7-7.0 mV), and Q4 (≥7.1 mV). VRLA at any region was reduced as VGLA decreased. VGLA and VRLA did not differ between Q4 and controls. The presence of LVAs increased as VGLA decreased at any voltage cutoff. Biopsies revealed 11±6% fibrosis, which was inversely correlated with both Vbiopsy and VGLA (r=-0.71 and -0.72, respectively). Vbiopsy was correlated with VGLA (r=0.82). Conclusions Voltage reduction in the LA is a diffuse process associated with fibrosis. Presence of LVAs reflects diffuse voltage reduction of the LA.

Palisading-like arrangement of immature ganglion cell in myenteric ganglia is a unique pathological feature of immaturity of ganglia.

BACKGROUND: Immaturity of ganglia (IG), an allied disorder of Hirschsprung disease (AD-HSCR), develops as neonatal ileus, but the dysmotility spontaneously resolves after several months. The diagnosis of IG using HE staining is often difficult. We herein report a new pathological finding of IG called the 'palisading-like pattern', which may be helpful for improving the diagnostic accuracy. METHODS: Cases of IG that were managed over the past 28 years were retrospectively reviewed. We investigated the clinical course and pathological findings for Hematoxylin-Eosin (HE) staining. The conventional diagnostic criteria for IG were (1) a normal or slightly increased number of ganglion cells and (2) ganglion cells with small nuclei. RESULTS: Among the 155 cases, 28 were diagnosed with IG, and 10 were retrospectively confirmed by HE staining. A palisading-like pattern was confirmed at the time of the initial ileostomy (median age, 2.5 days), and the palisading-like pattern had completely disappeared by the time of stoma closure (median age, 215 days) in all 10 cases. A palisading-like pattern is not present in other diseases. CONCLUSIONS: Even if immunostaining data are not available for a further analysis, the detection of a palisading-like pattern on HE staining makes an accurate diagnosis possible. LEVEL OF EVIDENCE: LEVEL IV.

A role of the aryl hydrocarbon receptor in attenuation of colitis.

BACKGROUND AND AIMS: The aryl hydrocarbon receptor (AhR), which is a member of the basic helix-loop-helix/Per-Arnt-Sim homology superfamily, plays an important role in multiple biological functions, and AhR knockout (AhR KO) animals suffer from a variety of organ disorders including a decline in the efficacy of their immune system. In addition, AhR activation is known to aid the maintenance of homeostasis in vivo. In this study, we investigated whether AhR is functionally associated with intestinal immunity. METHODS AND RESULTS: In in vivo experiments, it was found that dextran sodium sulfate (DSS)-evoked colitis was more severe in AhR KO mice than in C57BL/6J wild type mice. It was also revealed that the administration of DSS increased the expression levels of AhR and CYP1A1 mRNA in the colon epithelium. In addition, oral administration of ß-naphthoflavone (ßNF), a non-toxic agonist of AhR, suppressed the pathogenesis of DSS-induced colitis. ßNF also attenuated DSS-induced colitis. In cell culture experiments, downregulation of AhR in human colon carcinoma SW480 cells enhanced the inflammatory responses evoked by lipopolysaccharide (LPS), and furthermore, AhR activation attenuated LPS-induced inflammatory responses, suggesting that AhR expressing intestinal epithelial cells are involved in the prevention of colitis. CONCLUSIONS: Our findings about the potential role of AhR activators in epithelial immune regulation aid our understanding of mucosal homeostasis and inflammatory bowl disease (IBD) and suggest that AhR activation has therapeutic value for the treatment of IBD.

Successful Catheter Ablation for Multiple Atrial Arrhythmias in a Patient with Situs Inversus Totalis.

A 70-year-old woman with situs inversus totalis underwent catheter ablation for atrial fibrillation and atrial flutter. Although her morphologic left atrium (LA) was enlarged, we performed cryoballoon ablation and liner radiofrequency ablation of the cava-tricuspid isthmus without mapping atrial arrhythmias. However, a different form of atrial tachycardia (AT) recurred. We performed catheter ablation a second time using a three-dimensional electroanatomic mapping system. AT was not terminated by the liner ablation at the roof of morphologic LA and mitral isthmus but sustained by changing the atrial activation sequence and cycle length. Multipolar mapping catheter revealed that fractionated low-amplitude potentials were densely located in a limited area of the anterior morphologic LA, and an activation map demonstrated the presence of small-circuit reentry with an extremely slow conduction at the anterior morphologic LA. A single energy application targeting the fragmented potentials successfully terminated the AT. We successfully treated multiple ATs with a complex anatomy using a three-dimensional electroanatomic mapping system.

Ultrasound-guided double central venous access for azygos vein via the ninth and tenth intercostal veins.

Some patients with intestinal failure, who are dependent on total parenteral nutrition for long periods, suffer from a lack of suitable conventional venous access points, including axillary, external jugular, internal jugular, subclavian, saphenous, and the brachio-cephalic and femoral veins, due to their occlusion. Furthermore, extensive central venous stenosis and/or thrombosis of the superior and inferior vena cava may preclude further catheterization, so uncommon routes must be used, which can be challenging. In such patients, the azygos vein via the intercostal vein is a viable candidate. Thoracotomy-assisted, thoracoscopy-assisted, and cut-down procedures are currently suggested such access. We found that ultrasound-guided percutaneous puncture method was a safe and minimally invasive approach and successfully placed two central venous lines in preparation for small bowel transplantation via two different intercostal veins (ninth and tenth). Although the lung was actually located just below the target veins, an ultrasound provided augmented and clear vision, which contributed to the safe performance of the procedure without the need for invasive surgical intervention, such as thoracotomy, thoracoscopy, or rib resection using the cut-down technique. Furthermore, constant positive-pressure ventilation during vein puncture under general anesthesia also helps avoid venous collapse. Despite carrying a slight risk of light injury to the lung, artery, and nerve along with the vein compared to other procedures, we believe that ultrasound-guided puncture under general anesthesia is feasible as a minimally invasive method.

Activation of the aryl hydrocarbon receptor induces hepatic steatosis via the upregulation of fatty acid transport.

The aryl hydrocarbon receptor (AHR) is a basic helix-loop-helix/Per-ARNT-Sim domain transcription factor, which is activated by various xenobiotic ligands. AHR is known to be abundant in liver tissue and to be associated with hepatic steatosis. However, it has not yet been elucidated how the activation of AHR promotes hepatic steatosis. The aim of this study is to clarify the role of AHR in hepatic steatosis. The intraperitoneal injection of 3-methylcholanthrene (3MC), a potent AHR ligand, into C57BL/6J mice significantly increased the levels of triglycerides and six long-chain monounsaturated fatty acids in the livers of mice, resulting in hepatic microvesicular steatosis. 3MC significantly enhanced the expression level of fatty acid translocase (FAT), a factor regulating the uptake of long-chain fatty acids into hepatocytes, in the liver. In an in vitro experiment using human hepatoma HepG2 cells, 3MC increased the expression level of FAT, and the downregulation of AHR by AHR siRNA led to the suppression of 3MC-induced FAT expression. In addition, the mRNA level of peroxisome proliferator-activated receptor (PPAR) α, an upstream factor of FAT, was increased in the livers of 3MC-treated mice. Taking together, AHR activation induces hepatic microvesicular steatosis by increasing the expression level of FAT.