Long-Term Effects of Rifaximin on Patients with Hepatic Encephalopathy: Its Possible Effects on the Improvement in the Blood Ammonia Concentration Levels, Hepatic Spare Ability and Refractory Ascites.

Background and Objectives: To investigate the long-term efficacy of rifaximin (RFX) for hyperammonemia and efficacy for refractory ascites in patients with cirrhosis. Materials and Methods: We enrolled 112 patients with liver cirrhosis who were orally administered RFX in this study. Changes in the clinical data of patients were evaluated up to 36 months after RFX administration. The primary endpoint was a change in blood ammonia levels. Secondary endpoints included changes in clinical symptoms, Child−Pugh (CP) score, number of hospitalizations, degree of refractory ascites, adverse events, and the relationship between RFX administration and the renin-angiotensin-aldosterone system. Results: An improved rate of overt hepatic encephalopathy (HE) of 82.7% was observed 3 months after RFX administration, which significantly induced a progressive decrease in blood ammonia concentration and an improved CP score up to 36 months. No serious RFX treatment-related adverse events were observed. 36.5% in patients after RFX administration improved refractory ascites. After RFX administration, patients with satisfactory control of hepatic ascites without addition of diuretic had lower renin concentration than those with poor control (p < 0.01). At less than 41 pg/mL renin concentration, the control of refractory ascites was significantly satisfactory (p < 0.0001). Conclusions: RFX reduced blood ammonia concentration and improved hepatic spare ability and the quality of life of patients with long-term HE to up to 36 months. Our study revealed the effects of RFX against refractory ascites, suggesting that renin concentration may be a predictive marker for assessing ascites control.

Irsogladine maleate alters expression of a tight junction protein in portal hypertensive gastropathy.

BACKGROUND AND AIM: Portal hypertensive gastropathy (PHG) is characterized by noninflammatory edema and vasodilatation of the lamina propria of the mucosal epithelium. In addition, the alterations of intercellular junction proteins and dilatation of the endothelial gaps have been reported. In this study, we examined whether irsogladine maleate (IM), a gastric mucosal protective agent, has the potential to improve PHG by restoration of tight junctions (TJs). METHODS: Twenty-four patients with PHG were registered and randomly assigned into two groups: 12 patients in the IM-administration group and 12 patients in the non-administration group. In the administration group, IM (4 mg/day) was administered orally for 12 weeks. Gastric mucosa with a red color in patients with PHG were obtained endoscopically on the registration day and 12 weeks later. The endoscopic findings were evaluated, an immunohistochemical analysis of claudin-3 (a TJ protein) expression in gastric mucosal tissues by a laser microscope was performed, and claudin-3 expression was quantified by western blot analysis. RESULTS: Irsogladine maleate improved the degree of PHG in 2/12 patients endoscopically, in contrast to none of the 12 patients in the non-administration group. Immunohistochemical analysis showed that expression of claudin-3 increased in 8/12 patients in the IM-administration group and 2/12 patients in the non-administration group (P = 0.036). Western blot analysis revealed that the increase in claudin-3 after 12 weeks was significantly higher in the IM-administration group than in the non-administration group (P = 0.010). CONCLUSIONS: The present pilot study suggested that IM might improve the gastric mucosa in PHG through restoration of TJ-protein claudin-3.

Development of rat duodenal monolayer model with effective barrier function from rat organoids for ADME assay.

The in-depth analysis of the ADME profiles of drug candidates using in vitro models is essential for drug development since a drug's exposure in humans depends on its ADME properties. In contrast to efforts in developing human in vitro absorption models, only a limited number of studies have explored models using rats, the most frequently used species in in vivo DMPK studies. In this study, we developed a monolayer model with an effective barrier function for ADME assays using rat duodenal organoids as a cell source. At first, we developed rat duodenal organoids according to a previous report, but they were not able to generate a confluent monolayer. Therefore, we modified organoid culture protocols and developed cyst-enriched organoids; these strongly promoted the formation of a confluent monolayer. Furthermore, adding valproic acid to the culture accelerated the differentiation of the monolayer, which possessed an effective barrier function and apicobasal cell polarity. Drug transporter P-gp function as well as CYP3A activity and nuclear receptor function were confirmed in the model. We expect our novel monolayer model to be a useful tool for elucidating drug absorption processes in detail, enabling the development of highly absorbable drugs.

Long-term outcome and eligibility of radiofrequency ablation for hepatocellular carcinoma over 3.0 cm in diameter.

Percutaneous radiofrequency ablation (RFA) is effective for the treatment of small hepatocellular carcinoma (HCC) with a diameter ≤ 3.0 cm. The present study aimed to elucidate the prognostic factors and clarify the indication of treatment for RFA outcomes in patients with HCC with a diameter > 3.0 cm. Among 2188 patients with HCC who underwent RFA, 100 patients with HCC with a diameter > 3.0 cm were enrolled in this study between August, 2000 and August, 2021. We analyzed local therapeutic efficacy, long-term outcomes, and prognostic factors in patients with HCC with a diameter > 3.0 cm. Among all patients, 77 patients achieved complete ablation in one session. There were no treatment-related deaths or major complications. Local tumor recurrence occurred in 48% (n = 48) of the patients, and distant tumor recurrence occurred in 82% (n = 82) of the patients during the study period. The survival rates at 1-, 3-, 5-, 10-, and 15- years were 93.0%, 66.0%, 40.0%, 15.5%, and 10.2%, respectively. Cox proportional hazards regression analysis confirmed that distant tumor recurrence, Child-Pugh class B, and pre-ablation des-γ-carboxy prothrombin (DCP) levels ≥ 200 mAU/mL were independent unfavorable prognostic factors with a hazard ratio of 3.34 (95% CI, 1.57-7.11; P = 0.002), 2.43 (95% CI, 1.35-4.37; P = 0.003), and 1.83 (95% CI, 1.14-2.93; P = 0.012), respectively. In conclusion, patients with HCC with a diameter > 3.0 cm with Child-Pugh class A and DCP levels < 200 mAU/mL might be eligible for RFA treatment.

Two Cases of Rapidly Progressive Fatty Liver Disease due to Pancreatic Exocrine Insufficiency without a History of Surgery.

We herein report two cases of rapidly progressive fatty liver (FL) disease due to pancreatic exocrine insufficiency (PEI) without a surgical history. Two women, 59 and 72 years old, with no history of abdominal surgery presented to our hospital with severe anorexia and nausea persisting for one week. Examinations revealed progressive, marked FL disease with hepatomegaly and PEI, for which pancreatic enzyme replacement therapy was effective. Commonly known causes of PEI include chronic pancreatitis, abdominal surgery (e.g. pancreaticoduodenectomy), pancreatic cancer, and obstruction of the pancreatic duct, none of which were present in either of these two cases.

Hepatitis C Virus-associated Cryoglobulinemic Livedo Reticularis Improved with Direct-acting Antivirals.

We herein report a case of hepatitis C virus (HCV)-associated cryoglobulinemic livedo reticularis in a woman in her 60s that improved with direct-acting antivirals (DAAs). Hyperpigmentation was observed in both lower legs, and a skin biopsy confirmed livedo reticularis, suggesting a relationship with cryoglobulinemia and HCV infection. DAAs with an NS5A inhibitor+NS3/4A protease inhibitor (glecaprevir/pibrentasvir) were administered for eight weeks, and a sustained virological response (SVR) was obtained. The disappearance of serum cryoglobulin was confirmed approximately two years after an SVR was obtained and livedo reticularis was improved. DAA therapy can be an effective therapeutic option for extrahepatic complications associated with HCV infection.

Disappearance of Hepatocellular Adenoma in a Patient with Cornelia de Lange Syndrome after Treatment with Transcatheter Arterial Embolization.

Cornelia de Lange syndrome (CdLS) is a congenital disorder occasionally associated with congenital portosystemic shunt (CPSSs). We herein report a patient with CdLS and CPSS who developed hepatocellular adenomas (HCAs). The patient presented to our hospital for the further investigation of newly diagnosed liver tumors. Imaging findings and pathological examination results indicated that the liver tumors were inflammatory HCAs that subsequently shrank following transcatheter arterial embolization (TAE). Patients with CdLS and CPSS are at risk of developing HCAs, and TAE may be an effective management strategy for HCA in these patients.

Validation of a method to analyze size distribution of crovalimab-complement C5-eculizumab complexes in human serum.

Background: Crovalimab is a humanized monoclonal antibody targeting human complement C5. Patients switching from eculizumab to crovalimab are expected to form drug-target-drug complexes (DTDCs), since these antibodies each bind to a different epitope on complement C5. An analytical method to evaluate the size distribution of these DTDCs was developed and validated. Methods: Human serum samples were separated by size-exclusion chromatography (SEC) into eight fractions, and the concentration of crovalimab in each fraction was measured by ELISA. We evaluated SEC, ELISA and the combination of both methods (SEC-ELISA). Results: Predetermined validation acceptance criteria were met. Conclusion: The DTDC assay method was successfully validated. It enables us to evaluate the impact of DTDCs on clinical outcomes.

Novel Endoscopic Therapy for Gastric Varices Using Direct Forward-Viewing Endoscopic Ultrasonography.

Gastric varices (GV) carry a high risk of massive hemorrhage because of potential rupture. To reduce the risk associated with GV, patients need to undergo hemostatic and preventive treatment. The objective of this retrospective study was to evaluate the usefulness of a new method, direct forward-viewing endoscopic ultrasonography (DFV-EUS) for the treatment of GV. We performed endoscopic injection sclerotherapy with histoacryl (EIS-HA) using DFV-EUS for GV in four patients. The paracentesis success rate was 75% (3/4). DFV-EUS has a significant advantage for the treatment of GV in that it can show physicians endoscopic and ultrasound views in real time during the delivery of the sclerosant into the GV. However, the proper use of the ultrasound view must be elucidated through further research for safer and more effective therapy. In the presence of distance between the mucosal surface and vascular lumen or when the blood flow site requires puncture as an additional treatment, DFV-EUS might be a good candidate for the treatment of GV. Altogether, EIS-HA with DFV-EUS might be a new therapeutic option for patients with GV.

Antigen-dependent internalization is related to rapid elimination from plasma of humanized anti-HM1.24 monoclonal antibody.

Anti-HM1.24 monoclonal antibody (AHM) is a humanized anti-HM1.24 monoclonal antibody that binds to the HM1.24 antigen, a protein that is highly expressed in multiple myeloma cells. The pharmacokinetics of AHM was determined in experiments in which AHM was administered intravenously to cynomolgus monkeys. The area under the plasma concentration-time curve increased by more than the dose ratio between 2 and 20 mg/kg, and nonlinear pharmacokinetics was observed. The elimination half-life of AHM from the plasma was 7.56 h at 2 mg/kg and 28.6 h at 20 mg/kg, which was shorter than that observed for other therapeutic humanized monoclonal antibodies, such as trastuzumab and bevacizumab. Although antibodies to AHM were detected in all monkeys on or after 10 days of administration, there was a temporal disassociation between the rapid elimination of AHM and the appearance of anti-AHM antibodies. HM1.24 antigen-dependent internalization and intracellular metabolism of AHM were investigated in peripheral blood mononuclear, KPMM2, and U937 cells. In all cases, AHM was rapidly internalized from the cell surface; this internalization was significantly prevented by phenylarsine oxide in KPMM2 cells, an inhibitor of receptor-mediated endocytosis, and the internalized AHM was subsequently degraded within the cells. Furthermore, immunofluorescence microscopy revealed that the internalized AHM is delivered to and degraded in late endosomes/lysosomes. Taken together, our results suggest that the rapid elimination of AHM from plasma in monkey is due to HM1.24 antigen-dependent internalization followed by delivery to the lysosomes.

Unresectable Ectopic Hepatocellular Carcinoma Treated with Sorafenib.

Ectopic hepatocellular carcinoma (HCC) is a rare malignancy, which manifests similar morphology and immunohistochemistry to intrahepatic HCC. Herein, we report a case of ectopic HCC in a 73-year-old male. The patient presented to our hospital with gradually progressing right lower abdominal pain, and enhanced computed tomography revealed multiple nodules in the peritoneum without intrahepatic mass. A diagnostic laparoscopy was performed, and the final pathology result confirmed that it was HCC. Additional laboratory tests showed elevated serum alpha-fetoprotein and protein induced by vitamin K absence-II (PIVKA-II) levels, suggesting our diagnosis. The patient received sorafenib, a tyrosine kinase inhibitor (TKI), for unresectable ectopic HCC. However, the tumor progressed, and because of tarry stools and hemorrhagic anemia, sorafenib was ceased after 7 months of therapy. One month after the cessation of sorafenib, the PIVKA-II level increased abruptly, and the patient died 1 year after diagnosis. The effective treatment for unresectable ectopic HCC is still unknown. Additional cases should be accumulated to determine the effect of TKI on ectopic HCC.

Exploratory Research on the Relationship between Human Gut Microbiota and Portal Hypertension.

Objective The relationship between gut microbiota and portal hypertension remains unclear. We investigated the characteristics of the gut microbiota in portal hypertension patients with esophago-gastric varices and liver cirrhosis. Methods Thirty-six patients (12 patients with portal hypertension, 12 healthy controls, and 12 non-cirrhosis patients) were enrolled in this university hospital study. Intestinal bacteria and statistical analyses were performed up to the genus level using the terminal restriction fragment length polymorphism method targeting 16S ribosomal RNA genes, with diversified regions characterizing each bacterium. Results Levels of Lactobacillales were significantly higher (p=0.045) and those of Clostridium cluster IV significantly lower (p=0.014) in patients with portal hypertension than in other patients. This Clostridium cluster contains many butanoic acid-producing strains, including Ruminococcace and Faecalibacterium prausnitzii. Clostridium cluster IX levels were also significantly lower (p=0.045) in portal hypertension patients than in other patients. There are many strains of Clostridium that produce propionic acid, and the effects on the host and the function of these bacterial species in the human intestine remain unknown. Regarding the Bifidobacterium genus, which is supposed to decrease as a result of cirrhosis, no significant decrease was observed in this study. Conclusion In the present study, we provided information on the characteristics of the gut microbiota of portal hypertension patients with esophago-gastric varices due to liver cirrhosis. In the future, we aim to develop probiotic treatments following further analyses that include the species level, such as the intestinal flora analysis method and next-generation sequencers.

Simultaneous determination of nitroglycerin and dinitrate metabolites in metabolism studies using liquid chromatography-mass spectrometry with electrospray ionization.

We have developed a liquid chromatographic-mass spectrometric method for the simultaneous determination of nitroglycerin (NTG) and its active metabolites, glyceryl 1,2-dinitrate (1,2-GDN) and glyceryl 1,3-dinitrate (1,3-GDN), for metabolism studies in cell cultures. 1,2,4-Butanetriol-1,4-dinitrate was chosen as an internal standard. Using a linear gradient of water/methanol containing 0.025 mM NH(4)Cl, the compounds were eluted within 12.5 min on an Allure Aqueous C(18) column (100 mm x 2.1 mm). Detection and quantification was achieved with multiple reaction monitoring in the negative ion mode. Intra- and inter-day variabilities for simultaneous determination of the three nitrates were below 10 and 18%, respectively, over a range of NTG and GDN concentrations of 0.5-15 ng/ml. The lower limit of quantification was found to be about 0.01 ng on column. Application of this method was illustrated through in vitro metabolism studies of NTG in culture media bathing LLC-PK1 cells and human vascular smooth muscle cells (HA-VSMC) at 37 degrees C. The degradation half-life of NTG was found to be 4.5 +/- 0.4 h and 39.2 +/- 0.02 h, respectively, for LLC-PK1 cells versus HA-VSMC. At 5 h, the 1,2-GDN versus 1,3-GDN metabolite distribution ratio in the bathing medium was found to be 1.5 +/- 0.1 and 0.2 +/- 0.02 for LLC-PK1 and HA-VSMC cells, respectively. With this method, the degradation half-life of NTG in rat plasma at 37 degrees C was shown to be 26.8 +/- 1.8 min, consistent with previous values obtained using gas chromatography.

Nonlinear intestinal pharmacokinetics of mitemcinal, the first acid-resistant non-peptide motilin receptor agonist, in rats.

The objective was to investigate the mechanism of nonlinear pharmacokinetics of mitemcinal, the first acid-resistant non-peptide motilin agonist, in rats. Super-proportional increases of the cumulative rates of radioactivity excreted into bile and urine following oral administration of [3H]-mitemcinal suggested nonlinear absorption of mitemcinal in rats. To evaluate the fraction dose absorbed (Fa) and intestinal availability (Fg), [3H]-mitemcinal was orally administrated to rats, and tritium radioactivity and unchanged mitemcinal concentration were determined in the portal blood. Fa values for 0.2 mg/kg1, 0.5 mg/kg, and 5.0 mg/kg dose groups were 0.314, 0.353, and 0.569, respectively. Corresponding Fg values were 0.243, 0.296, and 0.513, respectively. In Caco-2 experiments, the permeation of [3H]-mitemcinal in the secretory direction was larger than in the absorptive direction and was inhibited by P-glycoprotein (P-gp) substrate digoxin. The results indicate that the saturation of P-gp-mediated membrane permeation and intestinal metabolism causes the nonlinear pharmacokinetics of mitemcinal in rats.