Covalent Bond between the Lys-255 Residue and the Main Chain Is Responsible for Stable Retinal Chromophore Binding and Sodium-Pumping Activity of Krokinobacter Rhodopsin 2.

Microbial rhodopsins are light-receptive proteins with various functions triggered by the photoisomerization of the retinal chromophore from the all-trans to 13-cis configuration. A retinal chromophore is covalently bound to a lysine residue in the middle of the seventh transmembrane helix via a protonated Schiff base. Bacteriorhodopsin (BR) variants lacking a covalent bond between the side chain of Lys-216 and the main chain formed purple pigments and exhibited a proton-pumping function. Therefore, the covalent bond linking the lysine residue and the protein backbone is not considered a prerequisite for microbial rhodopsin function. To further examine this hypothesis regarding the role of the covalent bond at the lysine side chain for rhodopsin functions, we investigated K255G and K255A variants of sodium-pumping rhodopsin, Krokinobacter rhodopsin 2 (KR2), with an alkylamine retinal Schiff base (prepared by mixing ethyl- or n-propylamine and retinal (EtSB or nPrSB)). The KR2 K255G variant incorporated nPrSB and EtSB as similarly to the BR variants, whereas the K255A variant did not incorporate these alkylamine Schiff bases. The absorption maximum of K255G + nPrSB was 524-516 nm, which was close to the 526 nm absorption maximum of the wild-type + all-trans retinal (ATR). However, the K255G + nPrSB did not exhibit any ion transport activity. Since the KR2 K255G variant easily released nPrSB during light illumination and did not form an O intermediate, we concluded that a covalent bond at Lys-255 is important for the stable binding of the retinal chromophore and formation of an O intermediate to achieve light-driven Na+ pump function in KR2.

Leukotriene receptor antagonists enhance HCC treatment efficacy by inhibiting ADAMs and suppressing MICA shedding.

In our previous genome-wide association study, we demonstrated the association between MHC class I-related chain A (MICA) and hepatocellular carcinoma (HCC) development in patients with chronic hepatitis C. Increasing membrane-bound MICA (mMICA) in cancer cells by reducing MICA sheddases facilitates natural killer (NK) cell-mediated cytotoxicity. Our recent study clarified that A disintegrin and metalloproteases (ADAM), including ADAM9, are MICA sheddases in HCC, and that the suppression of ADAMs increases mMICA, demonstrating the rationality of mMICA-NK targeted therapy. Furthermore, we showed that regorafenib suppresses ADAM9 transcriptionally and translationally. A library of FDA-approved drugs was screened for more efficient inhibitors of ADAM9. Flow cytometry evaluation of the expression of mMICA after treatment with various candidate drugs identified leukotriene receptor antagonists as potential ADAM9 inhibitors. Furthermore, leukotriene receptor antagonists alone or in combination with regorafenib upregulated mMICA, which was in turn downregulated by leukotriene C4 and D4 via ADAM9 function. Our study demonstrates that leukotriene receptor antagonists could be developed as novel drugs for immunological control and suppression of ADAM9 in HCC. Further, leukotriene receptor antagonists should be explored as combination therapy partners with conventional multi-kinase inhibitors for developing therapeutic strategies with enhanced efficacies for HCC management and treatment.

meta-Non-flat substituents: a novel molecular design to improve aqueous solubility in small molecule drug discovery.

Aqueous solubility is a key requirement for small-molecule drug candidates. Here, we investigated the regioisomer-physicochemical property relationships of disubstituted benzenes. We found that meta-isomers bearing non-flat substituents tend to possess the lowest melting point and the highest thermodynamic aqueous solubility among the regioisomers. The examination of pharmaceutical compounds containing a disubstituted benzene moiety supported the idea that the introduction of a non-flat substituent at the meta position of a benzene substructure would be a promising approach for medicinal chemists aiming to improve the thermodynamic aqueous solubility of drug candidates, even though it might not be universally effective.

Extracorporeal Membrane Oxygenation for Secondary Organizing Pneumonia after Severe SARS-CoV-2 Infection: A Case Report.

(Background) COVID-19 is caused by SARS-CoV-2 infection and may result in unfavorable outcomes. A recent large-scale study showed that treatment with dexamethasone leads to favorable outcomes in patients with severe COVID-19, and the use of extracorporeal membrane oxygenation (ECMO) has also been shown to improve outcomes. Recently, secondary organizing pneumonia (SOP) has been reported after SARS-CoV-2 infection, but the diagnostic and treatment strategies are still unclear. (Case presentation) Here, we report a patient with severe COVID-19 who developed SOP even after the use of dexamethasone, for whom the introduction of ECMO on the 19th day after hospitalization led to a favorable outcome. (Conclusions) Life-threatening SOP may evolve even after the use of dexamethasone, and the late-phase introduction of ECMO may save such patients with COVID-19.

The Power of Assemblies at Interfaces: Nanosensor Platforms Based on Synthetic Receptor Membranes.

Synthetic sensing materials (artificial receptors) are some of the most attractive components of chemical/biosensors because of their long-term stability and low cost of production. However, the strategy for the practical design of these materials toward specific molecular recognition in water is not established yet. For the construction of artificial material-based chemical/biosensors, the bottom-up assembly of these materials is one of the effective methods. This is because the driving forces of molecular recognition on the receptors could be enhanced by the integration of such kinds of materials at the 'interfaces', such as the boundary portion between the liquid and solid phases. Additionally, the molecular assembly of such self-assembled monolayers (SAMs) can easily be installed in transducer devices. Thus, we believe that nanosensor platforms that consist of synthetic receptor membranes on the transducer surfaces can be applied to powerful tools for high-throughput analyses of the required targets. In this review, we briefly summarize a comprehensive overview that includes the preparation techniques for molecular assemblies, the characterization methods of the interfaces, and a few examples of receptor assembly-based chemical/biosensing platforms on each transduction mechanism.

In Vivo Extracellular pH Mapping of Tumors Using Electron Paramagnetic Resonance.

An electron paramagnetic resonance (EPR)-based method for noninvasive three-dimensional extracellular pH mapping was developed using a pH-sensitive nitroxyl radical as an exogenous paramagnetic probe. Fast projection scanning with a constant magnetic field sweep enabled the acquisition of four-dimensional (3D spatial +1D spectral) EPR images within 7.5 min. Three-dimensional maps of pH were reconstructed by processing the pH-dependent spectral information on the images. To demonstrate the proposed method of pH mapping, the progress of extracellular acidosis in tumor-bearing mouse legs was studied. Furthermore, extracellular pH mapping was used to visualize the spatial distribution of acidification in different tumor xenograft mouse models of human-derived pancreatic ductal adenocarcinoma cells. The proposed EPR-based pH mapping method enabled quantitative visualization of regional changes in extracellular pH associated with altered tumor metabolism.

Serum autotaxin is a useful liver fibrosis marker in patients with chronic hepatitis B virus infection.

AIM: Autotaxin (ATX) is a secreted enzyme that is considered to be associated with liver damage as well as fibrosis. This study assessed the ability of ATX to diagnose liver fibrosis in patients with chronic hepatitis B virus (HBV) infection. METHODS: Serum ATX levels were retrospectively evaluated in 101 treatment-naïve patients with HBV-related chronic hepatitis or cirrhosis, all of whom had undergone liver biopsy at our hospital. RESULTS: Serum ATX concentration increased significantly according to liver fibrosis stage in overall (r = 0.46, P < 0.0001), male (r = 0.55, P < 0.0001), and female (r = 0.52, P = 0.0006) patient groups. When analyzed by gender, serum ATX was one of the most reliable markers for all fibrosis stages compared with other tested non-invasive markers, which included hyaluronic acid, type IV collagen 7S, aspartate aminotransferase-to-platelet ratio index, and fibrosis index based on four factors, according to receiver operating characteristic curve analysis. CONCLUSION: Based on this histologically proven data, ATX represents a novel non-invasive biomarker for liver fibrosis in HBV-infected patients.

Association between serum soluble CD14 and IL-8 levels and clinical outcome in primary biliary cholangitis.

BACKGROUND & AIMS: Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts that often leads to liver decompensation and liver failure. Although the biochemical response to ursodeoxycholic acid (UDCA) can predict disease outcome in PBC, few biomarkers have been identified as prognostic tools applicable prior to UDCA treatment. We therefore sought to identify such indicators of long-term outcome in PBC in the Japanese population. METHODS: The prebiopsy serum samples and subsequent clinical data of 136 patients with PBC treated with UDCA were analysed over a median follow-up period of 8.8 years. Serum levels of biomarkers related to microbial translocation (sCD14, EndoCAb and I-FABP) were measured along with those of 33 cytokines and chemokines and additional auto-antibodies. Associations between the tested parameters and the clinical outcomes of liver decompensation and liver-related death/liver transplantation were evaluated using the Cox proportional hazards model with stepwise methods and Kaplan-Meier analysis. RESULTS: Elevated levels of serum IL-8, and sCD14 before UDCA therapy were significantly associated with both liver decompensation and liver-related death/liver transplantation. In multivariate analyses, IL-8≥46.5 pg/mL or sCD14≥2.0 µg/mL at enrolment demonstrated the same results. Kaplan-Meier analysis also revealed IL-8 and sCD14 to be significantly associated with a poor outcome. sCD14 was significantly correlated with IL-8. EndoCAb and I-FABP were not related to disease outcome. CONCLUSIONS: Serum IL-8 and sCD14 levels before UDCA therapy represent noninvasive surrogate markers of prognosis in patients with PBC.

Serum Wisteria floribunda agglutinin-positive human Mac-2 binding protein may predict liver fibrosis and progression to hepatocellular carcinoma in patients with chronic hepatitis B virus infection.

AIM: Serum glycosylated Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA+ -M2BP) is a reliable, non-invasive marker of liver fibrosis. This study assessed the ability of WFA+ -M2BP to diagnose liver fibrosis in patients with chronic hepatitis B virus (HBV) infection and evaluated WFA+ -M2BP as a predictor of hepatocellular carcinoma (HCC) development. METHODS: Serum WFA+ -M2BP values were retrospectively evaluated in 112 treatment-naïve patients with HBV-related chronic hepatitis and cirrhosis who had undergone liver biopsy at our hospital. RESULTS: Serum WFA+ -M2BP levels were significantly related with liver fibrosis (r = 0.3725, P = 0.001). Fibrosis stage F2, F3, and F4 had a cut-off index of 0.94, 1.26, and 1.26, respectively. For diagnosing F ≥ 2 fibrosis, the area under the receiver-operating characteristic curve for WFA+ -M2BP was 0.713 and comparable with those of other non-invasive fibrosis markers, such as hyaluronic acid, type IV collagen 7S, aspartate aminotransferase-to-platelet ratio index, fibrosis-4 index, serum albumin, and platelet count. Multivariate analysis identified male, WFA+ -M2BP ≥0.71, alanine aminotransferase ≥80 IU/L, and platelet count <14.5 × 109 /L as independent risk factors for the development of HCC in patients with HBV infection. CONCLUSIONS: Serum WFA+ -M2BP values appear to be useful for assessing liver fibrosis stage and are independently associated with HCC development in patients with chronic HBV infection.

Clinicopathological characteristics of non-B non-C hepatocellular carcinoma without past hepatitis B virus infection.

AIM: Past hepatitis B virus (HBV) infection is considered a risk factor for hepatocarcinogenesis, but the clinicopathological characteristics of non-B non-C hepatocellular carcinoma (NBNC-HCC) excluding past HBV infection have not been investigated. This study aimed to clarify the clinicopathological features of strictly defined NBNC-HCC. METHODS: Among HCC patients who underwent surgical resection at our affiliated hospitals in Nagano prefecture, Japan, between 1996 and 2012, 77 were negative for serum anti-HBV core/surface antibodies in addition to HBV surface antigen and anti-hepatitis C virus antibody without signs of autoimmune liver disease, Wilson disease, or hemochromatosis. These patients were divided into the alcohol intake-positive group (ethanol intake >20 g/day, n = 31), non-alcoholic fatty liver group (steatosis >5% and ethanol intake <20 g/day, n = 30), and cryptogenic group (no ethanol intake or steatosis, n = 16). Preoperative clinical parameters, tumor and background liver pathology, and prognosis were analyzed. RESULTS: Advanced fibrosis and steatosis were detected in 64% and 60% of all patients, respectively. Approximately 85% of the alcohol intake-positive patients had advanced fibrosis. Non-alcoholic fatty liver HCC subjects had the highest body mass index and prevalence of diabetes, but 30-40% had none to mild fibrosis. The cryptogenic group of HCC patients had the lowest incidence of accompanying hepatic inflammation/fibrosis but the largest tumor size. Recurrence/survival rates were comparable among the groups. CONCLUSIONS: Liver fibrosis and steatosis are risk factors of HCC regardless of past HBV infection and ethanol consumption. The present results also indicate the possibility of hepatocarcinogenesis independent of hepatic steatosis, inflammation and fibrosis, ethanol intake, and past HBV infection.

An Activatable Photosensitizer Targeted to γ-Glutamyltranspeptidase.

We adopted a spirocyclization-based strategy to design γ-glutamyl hydroxymethyl selenorhodamine green (gGlu-HMSeR) as a photo-inactive compound that would be specifically cleaved by the tumor-associated enzyme γ-glutamyltranspeptidase (GGT) to generate the potent photosensitizer HMSeR. gGlu-HMSeR has a spirocyclic structure and is colorless and does not show marked phototoxicity toward low-GGT-expressing cells or normal tissues upon irradiation with visible light. In contrast, HMSeR predominantly takes an open structure, is colored, and generates reactive oxygen species upon irradiation. The γ-glutamyl group thus serves as a tumor-targeting moiety for photodynamic therapy (PDT), switching on tumor-cell-specific phototoxicity. To validate this system, we employed chick chorioallantoic membrane (CAM), a widely used model for preliminary evaluation of drug toxicity. Photoirradiation after gGlu-HMSeR treatment resulted in selective ablation of implanted tumor spheroids without damage to healthy tissue.

Production of infectious HCV genotype 1b virus in cell culture using a novel Set of adaptive mutations.

BACKGROUND: Despite the high prevalence of genotype 1b hepatitis C virus (HCV) among patients, a cell culture system that permits entire viral life cycle of genotype 1b isolates is limited. To develop a cell-cultured hepatitis C virus (HCVcc) of genotype 1b, the proper combination of HCV genomic variants and host cells is essential. HCV genomes isolated from patients with distinctive symptoms may provide the variants required to establish an HCVcc of genotype 1b. RESULTS: We first established subgenomic replicons in Huh7 cells using HCV cDNAs isolated from two patients: one with fulminant hepatitis after liver transplantation (TPF1) and another with acute hepatitis and moderate symptoms (sAH). Replicons established from TPF1 and sAH showed mutations in NS4B and in NS3 and NS5A, respectively. Using these replication machineries, we constructed HCV genomic RNAs for each isolate. Virus infectivity was evaluated by a focus-forming assay, which is dependent on the intracellular expression of core antigen, and production of virus particles was assessed by density-gradient centrifugation. Infectious virus was only observed in the culture medium of cells transfected with TFP1 HCV RNA. A chimeric genome with the structural segment (5'-untranslated region [UTR] through NS2) from sAH and the replication machinery (NS3 through 3'-UTR) from TPF1 exhibited greater infectivity than did TFP1, despite formation of deficient virus particles in sAH, suggesting that this genomic segment potentiates virus particle formation. To identify the responsible variants, infectious virus formation was assessed in a chimeric genome carrying parts of the sAH structural segment of the TPF1 genome. A variant in NS2 (M170T) was identified that enhanced infectious virus formation. HCVcc carrying an NS2 gene encoding the M170T substitution and adaptive mutations in NS4B (referred to as TPF1-M170T) infected naïve cured Huh7 cells in a CD81-dependent manner. CONCLUSIONS: We established a novel HCVcc of genotype 1b in Huh7 cells by introducing an amino acid variant in NS2 and adaptive mutations in NS4B from HCV genomic RNA isolated from a patient with fulminant HCV after liver transplantation.

Liver stiffness-spleen size-to-platelet ratio risk score identifies esophageal varices in Japanese patients with chronic hepatitis C.

AIM: Non-invasive methods are needed to identify esophageal varices (EV) in patients with chronic liver disease. To this end, we evaluated liver stiffness (LS)-spleen diameter-to-platelet ratio risk score (LSPS) in predicting EV among Japanese chronic hepatitis C patients. METHODS: A total of 99 patients with chronic hepatitis C who had undergone endoscopy, LS measurement and ultrasonography between 2013 and 2014 were enrolled. Clinical data were compared with those for other non-invasive markers (platelet count, aspartate aminotransferase-to-platelet ratio, FIB-4 index and platelet-to-spleen ratio), spleen size, LS and controlled attenuation parameter. Diagnostic applicability was assessed by the area under the receiver-operator curve (AUC) and predictive values along with multivariate logistic regression. RESULTS: LSPS was significantly correlated to the grade of EV (ρ = 0.617, P < 0.001) and was superior to the other non-invasive indices for determination of EV. LSPS was independently associated with EV by multivariate logistic regression analysis (odds ratio, 3.079; 95% confidence interval [CI], 2.137-4.438; P < 0.001). The cut-off value of LSPS for EV was 0.7, for which the AUC, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 0.928 (95% CI, 0.876-0.980), 86.3%, 89.6%, 70.4%, 95.8% and 88.9%, respectively. CONCLUSION: LSPS may also identify EV in patients with chronic hepatitis C in Japan. The clinical values of LSPS for EV risk merit further validation in larger prospective studies.

Controlled attenuation parameter is correlated with actual hepatic fat content in patients with non-alcoholic fatty liver disease with none-to-mild obesity and liver fibrosis.

AIM: Non-invasive steatosis-quantifying methods are required for non-alcoholic fatty liver disease (NAFLD) patients in order to monitor disease severity and assess therapeutic efficacy. Controlled attenuation parameter (CAP) evaluated with vibration-controlled transient elastography can predict the presence of steatosis, but its application to absolute hepatic fat quantitation remains unclear. The aim of this st\udy was to examine whether CAP is correlated with real hepatic fat content in NAFLD patients. METHODS: Eighty-two NAFLD patients who had undergone percutaneous liver biopsy were enrolled. CAP was measured using FibroScan(®) just before liver biopsy. The percentage of fat droplet area to hepatocyte area in biopsied specimen was determined morphometrically using computerized optical image analyzing system. The correlation between CAP and liver histology was examined. RESULTS: CAP showed an excellent correlation with actual liver fat percentage in the NAFLD patients with body mass index (BMI) of less than 28 kg/m(2) (r = 0.579, P < 0.0001), especially less than 25 kg/m(2) (r = 0.708, P < 0.01), but the meaningful correlation disappeared in the patients with BMI of 28 kg/m(2) or more. In the patients with BMI of less than 28 kg/m(2) , CAP quantitativeness was affected by the presence of stage 2-4 fibrosis, but not the presence of hepatocyte ballooning and severity of lobular inflammation. CONCLUSION: CAP may be a promising tool for quantifying hepatic fat content in NAFLD patients with none-to-mild obesity and liver fibrosis. Further improvement of CAP performance is needed for the NAFLD patients with BMI of more than 28 kg/m(2) or significant hepatic fibrosis.

Characteristics and prediction of hepatitis B e-antigen negative hepatitis following seroconversion in patients with chronic hepatitis B.

AIM: We analyzed the characteristics of alanine aminotransferase (ALT) abnormality after achieving hepatitis B e-antigen (HBeAg) seroconversion (SC) and other factors associated with the occurrence of HBeAg negative hepatitis. METHODS: We followed 36 patients with chronic hepatitis B from 3 years prior to at least 3 years after SC (mean, 11.6 years) and examined ALT, hepatitis B virus (HBV) DNA, HB surface antigen, HB core-related antigen (HBcrAg) levels and mutations related to HBeAg SC. RESULTS: ALT normalization (<31 IU/L for at least 1 year) was primarily observed until 2 years following SC, after which it became more infrequent. We next divided patients into abnormal (≥31 IU/L, n = 20) and normal (<31 IU/L, n = 16) groups based on integrated ALT level after the time point of 2 years from SC, and considered the former group as having HBeAg negative hepatitis in the present study. Although changes in median levels of ALT and HBcrAg differed significantly between the groups, multivariate analysis showed ALT normalization within 2 years after SC to be the only significant determining factor for this disease (P = 0.001). We then assessed the 19 patients whose ALT was normal at 2 years following SC, four of whom developed HBeAg negative hepatitis. Increased levels of HBV DNA (P = 0.037) and HBcrAg (P = 0.033) were significant factors of potential relevance. CONCLUSION: ALT abnormality after 2 years of SC may be evaluated as HBeAg-negative hepatitis. ALT, HBV DNA and HBcrAg levels may be useful in predicting the outcome of patients who achieve HBeAg SC.

Laparoscopic findings of congenital hepatic fibrosis: A case report and review of the published work.

A 33-year-old man visited a hospital after vomiting blood. Emergent esophagogastroduodenoscopy revealed the presence of varices in the lower esophagus. The patient did not have a past history of alcohol consumption and was negative for hepatitis B and C viruses. He was referred to our hospital for closer examination. Portal hypertension was detected by conventional imaging modalities, but signs of liver cirrhosis, thrombosis, stenosis, malformation of the portal vein and bile duct abnormalities were not observed. We performed laparoscopy-guided liver biopsy to examine the cause of portal hypertension. In addition to prominent development of collateral vessels on hepatic ligaments and the omenta, marbled whitish markings with black-green spots were dispersed over the liver surface, but nodular formation and lymphatic vesicles were not found. Biopsied specimen demonstrated severe dense fibrosis in portal areas and von Meyenburg complexes (vMC). Based on these findings, the diagnosis of congenital hepatic fibrosis (CHF) was made. Post-biopsy hemostasis was confirmed under laparoscopy and no major complications occurred after biopsy. We reviewed 11 cases of CHF which had undergone laparoscopy in Japan, including our case. Marbled whitish markings, black-green spots and collateral vessels were seen in 11, five and seven cases, respectively. When we encounter the patients having portal hypertension of unknown etiology, laparoscopy-guided liver biopsy should be considered as a safe and useful diagnostic procedure. Black-green spots in marbled whitish markings, which reflect vMC in broad fibrotic areas, are laparoscopic characteristics of CHF.

Selective ablation of ß-galactosidase-expressing cells with a rationally designed activatable photosensitizer.

We have developed an activatable photosensitizer capable of specifically inducing the death of ß-galactosidase-expressing cells in response to photoirradiation. By using a selenium-substituted rhodol scaffold bearing ß-galactoside as a targeting substituent, we designed and synthesized HMDESeR-ßGal, which has a non-phototoxic spirocyclic structure owing to the presence of the galactoside moiety. However, ß-galactosidase efficiently converted HMDESeR-ßGal into phototoxic HMDESeR, which exists predominantly in the open xanthene form. This structural change resulted in drastic recovery of visible-wavelength absorption and the ability to generate singlet oxygen ((1)O2). When HMDESeR-ßGal was applied to larval Drosophila melanogaster wing disks, which express ß-galactosidase only in the posterior region, photoirradiation induced cell death in the ß-galactosidase-expressing region with high specificity.

Identifying the Trends of Urinary microRNAs within Extracellular Vesicles for Esophageal Cancer.

Background: The advancement of multidisciplinary treatment has increased the need to develop tests to monitor tumor burden during treatment. We herein analyzed urinary microRNAs within extracellular vesicles from patients with esophageal squamous cell carcinoma (ESCC) and normal individuals using a microarray. Methods: Patients with advanced ESCC who underwent esophagectomy (A), endoscopic submucosal resection (ESD) (B), and healthy donors (C) were included. Based on microRNA expression among the groups (Analysis 1), microRNAs with significant differences between groups A and C were selected (Analysis 2). Of these candidates, microRNAs in which the change between A and C was consistent with the change between B and C were selected for downstream analysis (Analysis 3). Finally, microRNA expression was validated in patients with recurrence from A (exploratory analysis). Results: For analysis 1, 205 microRNAs were selected. For Analyses 2 and 3, the changes in 18 microRNAs were consistent with changes in tumor burden as determined by clinical imaging and pathological findings. The AUC for the detection of ESCC using 18 microRNAs was 0.72. In exploratory analysis, three of eighteen microRNAs exhibited a concordant trend with recurrence. Conclusions: The current study identified the urinary microRNAs which were significantly expressed in ESCC patients. Validation study is warranted to evaluate whether these microRNAs could reflect tumor burden during multidisciplinary treatment for ESCC.

Enantioselective synthesis of multisubstituted biaryl skeleton by chiral phosphoric acid catalyzed desymmetrization/kinetic resolution sequence.

Described herein is the enantioselective synthesis of multisubstituted biaryl derivatives by chiral phosphoric acid catalyzed asymmetric bromination. Two asymmetric reactions (desymmetrization and kinetic resolution) proceeded successively to afford chiral biaryls in excellent enantioselectivities (up to 99% ee). Both experimental and computational studies suggested that this excellent selectivity could be achieved via a highly organized hydrogen bond network among a substrate, a catalyst (chiral phosphoric acid), and a brominating reagent (N-bromophthalimide).

Muscular Metastasis of Hepatocellular Carcinoma: Case Report and Literature Review.

There are few case reports of hepatocellular carcinoma (HCC) metastasis to the skeletal muscle. A 78-year-old man developed a mass in the right shoulder. Washout of contrast medium during contrast-enhanced ultrasonography (CEUS) in both the primary HCC and the metastatic site was detected. Several nodules were scattered throughout the liver on an autopsy. In addition, the moderately differentiated HCC had metastasized to the right teres major muscle. Rare muscular metastasis should be considered if a hepatic tumor is moderately or poorly differentiated HCC. Early washout during CEUS is consistent with a pathological diagnosis of moderately or poorly differentiated HCC.