Potential Use of Mycobacterium paragordonae for Antimycobacterial Drug Screening Systems.

Our recent genome-based study indicated that Mycobacterium paragordonae (Mpg) has evolved to become more adapted to an intracellular lifestyle within free-living environmental amoeba and its enhanced intracellular survival within Acanthamoeba castellanii was also proved. Here, we sought to investigate potential use of Mpg for antimycobacterial drug screening systems. Our data showed that Mpg is more susceptible to various antibiotics compared to the close species M. marinum (Mmar) and M. gordonae, further supporting its intracellular lifestyle in environments, which would explain its protection from environmental insults. In addition, we developed two bacterial whole-cell-based drug screening systems using a recombinant Mpg stain harboring a luciferase reporter vector (rMpg-LuxG13): one for direct application to rMpg-LuxG13 and the other for drug screening via the interaction of rMpg-LuxG13 with A. castellanii. Direct application to rMpg-LuxG13 showed lower inhibitory concentration 50 (IC50) values of rifampin, isoniazid, clarithromycin, and ciprofloxacin against Mpg compared to Mmar. Application of drug screening system via the interaction of rMpg-LuxG13 with A. castellanii also exhibited lower IC50 values for rifampin against Mpg compared to Mmar. In conclusion, our data indicate that Mpg is more susceptible to various antibiotics than other strains. In addition, our data also demonstrate the feasibility of two whole cell-based drug screening systems using rMpg-LuxG13 strain for the discovery of novel anti-mycobacterial drugs.

Rationale and design to assess the efficacy and safety of HT047 in patients with acute ischemic stroke: A multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase II trial.

BACKGROUND: Though several neuroprotective agents have been evaluated as potential treatments for acute ischemic stroke, none have demonstrated a definitive treatment efficacy, which remains elusive. HT047 is an herbal extract of Scutellaria baicalensis and Pueraria lobata, both of which have been widely used to treat ischemic stroke in traditional Korean medicine. The aims of this trial are to investigate whether HT047 can improve neurologic status, particularly motor function, in acute ischemic stroke patients, and to determine the safety of HT047. METHODS: A multicenter, double-blind, randomized, placebo-controlled, 3-arm parallel group, phase II trial will be conducted in patients who have had an acute ischemic stroke within the past 14 days. The participating patients must have a Fugl-Meyer assessment (FMA) motor score ≤55, with arm or leg weakness, and Korean version of the National Institutes of Health Stroke scale (K-NIHSS) score of ≥4 and ≤15. Seventy-eight participants will be randomized in a 1:1:1 ratio and given high-dose HT047 (750 mg 3 times a day), low-dose HT047 (500 mg 3 times a day), or a placebo for 12 weeks. The primary endpoint is the change in FMA motor score between baseline and week 12. Secondary endpoints are as follows: the change in FMA motor score at weeks 4 and 8 from baseline; the change in FMA motor score at weeks 4, 8, and 12 from baseline according to the timing of treatment initiation (either within 1 week, or 1-2 weeks), or according to the presence of prognostic risk factors (hypertension, diabetes, dyslipidemia, etc); the change in K-NIHSS and Korean versions of the modified Rankin scale (K-mRS) and the modified Barthel index at weeks 4 and 12 from baseline; and the proportion of subjects at week 12 with a K-NIHSS score of 0 to 2, or with K-mRS scores of 0, ≤1, and ≤2. DISCUSSION: This study is a 1st-in-human trial of HT047 to explore the efficacy and safety in acute ischemic stroke patients. The results will provide the appropriate dosage and evidence of therapeutic benefit of HT047 for stroke recovery. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02828540) Registered July 11, 2016.

Self-Powered Coiled Carbon-Nanotube Yarn Sensor for Gastric Electronics.

The strong peristaltic contraction of the stomach facilitates mixing and emptying of ingested food, which occurs rhythmically at approximately 3 cycles/min (cpm) in humans. Generally, most patients with gastroparesis show gastric electrical dysrhythmia that is disrupted electrical signals controlling gastric contractions. For treatment of gastric electrical dysrhythmia, in vivo electrical impulses to the stomach via an implanted gastric stimulator have been known to restore these gastric deformations. Nevertheless, improved sensors to monitor gastric contractions are still needed in current gastric stimulators. Recently, we have developed a new technology converting mechanical motion to electrical energy by using stretch-induced capacitance changes of a coiled carbon-nanotube (CNT) yarn. For its potential use as a gastric deformation sensor, the performance of a coiled CNT yarn was evaluated in several biological fluids. For a sinusoidal stretch to 30%, the peak-to-peak open-circuit voltage (OCV) was consistently generated at frequencies below 0.1 Hz. This sinusoidal variation in OCV augmented as the strain increased from 10 to 30%. In an in vitro artificial gastric system, the OCV was approximately linearly proportional to the balloon volume, which can monitor periodic deformations of the balloon at 2, 3, and 4 cpm as shown for human gastric deformations. Moreover, stretchy coiled yarns generate the peak electrical voltage and power when deformed. The present study shows that a self-powered CNT yarn sensor can not only monitor the changes in frequency and amplitude of volumetric change but also generate electrical power by periodic deformations of the balloon. Therefore, it seems possible to automatically deliver accurate electrical impulses according to real-time evaluation of a patient's gastric deformation based on information on the frequency, amplitude, and rate of the OCV from CNT yarn.

Preclinical Evaluation of In Vitro and In Vivo Antiviral Activities of KCT-01, a New Herbal Formula against Hepatitis B Virus.

Hepatitis B virus (HBV) infectious diseases currently remain incurable due to limitations of conventional antivirals such as incapability of eradicating HBV DNA, prolonged use, drug resistance, and virological relapse. KCT-01, a 30% ethanol extract consisting of Artemisia capillaris, Sanguisorba officinalis, and Curcuma longa, was newly developed. The objective of this study was to investigate pharmacological activities of KCT-01 against HBV using HepG2.2.15 cells and a hydrodynamic injection model. KCT-01 significantly lowered antigen secretion, virion production, and pgRNA synthesis in HepG2.2.15 cells without affecting cell viability. KCT-01 administration also resulted in significant decrease of serum virion production, liver covalently closed circular (ccc) DNA levels, and mRNA synthesis of cytokines in the liver of mice injected with HBV DNA hydrodynamically. Interestingly, coadministration of KCT-01 with entecavir enhanced its in vitro and in vivo antiviral activities. Moreover, safety of KCT-01 was assured up to 5000 mg/kg in rats in both single and repeated-dose preclinical studies. Taken together, our findings demonstrate that KCT-01 is capable of suppressing HBV replication and inflammatory cytokine production in in vitro and in vivo models without showing toxicity, suggesting the potential of using KCT-01 alone or in combination with entecavir as antiviral agent.

Evaluation of antitumor activity of Artemisia capillaris extract against hepatocellular carcinoma through the inhibition of IL-6/STAT3 signaling axis.

Interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) signaling pathway plays critical roles in the development and progression of hepatocellular carcinoma (HCC). Artemisia capillaris (AC) has been widely used to treat various liver diseases including HCC as a herbal medicine. The effects of AC on IL-6/STAT3 signaling axis in HCC cells and subsequent anticancer activity of AC against HCC were analyzed using HCC cell lines and HBV W4P-LHB-expressing NIH3T3 cell line, which has been shown to gain tumorigenicity by activating IL-6/STAT3 signaling in our previous study. AC extract significantly suppressed the growth and colony formation of HCC cells. In addition, it inhibited the activation of STAT3 by IL-6 and subsequent synthesis of downstream molecules in HCC and W4P-NIH3T3 cells. Consequently, migration of cells was significantly suppressed by the AC extract. Collectively, the findings suggest that AC extract is capable of conferring various antitumor effects against HCC through the modulation of the IL-6/STAT3 pathway. The results provide a basis for the therapeutic use of AC in the treatment of HCC. Identification of the compound responsible for the effect may lead to the development of a novel anticancer agent against HCC.

Lateral Thalamic Infarction and the Vascular Geometry of the Posterior Cerebral Artery.

BACKGROUND: The geometric properties of the parental artery affect the development of local atherosclerosis and perforator infarction. In this study, we aimed at investigating the association between vascular geometry of the posterior cerebral artery (PCA) and the development of isolated lateral thalamic infarction (LTI), the most frequent type of thalamic infarction. METHODS: The geometric properties of the corresponding PCA in LTI patients were assessed and they include the diameters of the distal basilar artery (BA) and proximal PCA, distal BA - PCA angle, first PCA angle (angle between P1 and P2), and the presence of the posterior communicating artery (Pcom). These parameters obtained from the ipsilesional PCA were compared with the contralesional PCA and the corresponding PCA in age- and sex-matched controls. RESULTS: Forty-five LTI patients were enrolled. The ipsilesional PCA in LTI patients demonstrated a greater ipsilesional P1 - P2 angle (81.4 ± 22.6 vs. 71.3 ± 23.2°, respectively; p = 0.04) and a higher prevalence of Pcom (42.2 vs. 13.3%; p = 0.002) when compared to control subjects. In comparison with the contralesional PCA, ipsilesional PCA demonstrated a smaller diameter, larger angle between P1 and P2 segment, and a higher prevalence of Pcom. The presence of hyperlipidemia (OR 3.548 (1.283-9.811); p = 0.02) and Pcom (OR 3.507 (1.104-11.135); p = 0.03) was a factor that was independently associated with LTI. CONCLUSIONS: Local hemodynamics in the PCA may be influenced by the P1 - P2 angle and the presence of Pcom, which are associated with the development of LTI.

A Survey of Therapeutic Effects of Artemisia capillaris in Liver Diseases.

Artemisia capillaris has been recognized as an herb with therapeutic efficacy in liver diseases and widely used as an alternative therapy in Asia. Numerous studies have reported the antisteatotic, antioxidant, anti-inflammatory, choleretic, antiviral, antifibrotic, and antitumor activities of A. capillaris. These reports support its therapeutic potential in various liver diseases such as chronic hepatitis B virus (HBV) infection, cirrhosis, and hepatocellular carcinoma. In addition, several properties of its various constituents, which provide clues to the underlying mechanisms of its therapeutic effects, have been studied. This review describes the scientific evidence supporting the therapeutic potential of A. capillaris and its constituents in various liver diseases.

A shorter treatment duration may be sufficient for patients with Mycobacterium massiliense lung disease than with Mycobacterium abscessus lung disease.

BACKGROUND: Mycobacterium abscessus complex is the second most common organism isolated from patients with nontuberculous mycobacterial (NTM) lung disease in South Korea. This study aimed to compare clinical features and treatment outcomes of M. abscessus and Mycobacterium massiliense lung disease. METHODS: We retrospectively identified stored clinical isolates of M. abscessus complex as either M. abscessus or M. massiliense and reviewed medical records to compare clinical characteristics and treatment responses. All patients were treated empirically over several months with multidrug regimens, including a macrolide and one or more parenteral agents. RESULTS: Of the 249 patient isolates tested, 128 (59 with M. abscessus and 69 with M. massiliense) met the American Thoracic Society diagnostic criteria for NTM pulmonary disease, and treatment outcomes were analyzed in 48 patients (26 with M. abscessus and 22 with M. massiliense). The clinical and radiologic findings were similar between the two groups. Although the durations of parenteral and total treatment were significantly shorter in patients with M. massiliense than in those with M. abscessus (4.7 months vs 7.4 months, P = .006, and 12.1 months vs 16.3 months, P = .043), the treatment success rate was significantly higher in patients with M. massiliense (95.5%) than in M. abscessus cases (42.3%, P < .001). CONCLUSION: Patients with M. massiliense pulmonary infection responded better to this antibiotic strategy than those with M. abscessus infection. A shortened duration of treatment may be sufficient for M. massiliense pulmonary infection.

KIOM-4 Protects against Oxidative Stress-Induced Mitochondrial Damage in Pancreatic ß-cells via Its Antioxidant Effects.

The protective effect of KIOM-4, a mixture of plant extracts, was examined against streptozotocin (STZ)-induced mitochondrial oxidative stress in rat pancreatic ß-cells (RINm5F). KIOM-4 scavenged superoxide and hydroxyl radicals generated by xanthine/xanthine oxidase and Fenton reaction (FeSO(4)/H(2)O(2)), respectively, in a cell-free chemical system. In addition, a marked increase in mitochondrial reactive oxygen species (ROS) was observed in STZ-induced diabetic cells; this increase was attenuated by KIOM-4 treatment. Mitochondrial manganese superoxide dismutase (Mn SOD) activity and protein expression were down-regulated by STZ treatment and up-regulated by KIOM-4 treatment. In addition, NF-E2 related factor 2 (Nrf2), a transcription factor for Mn SOD, was up-regulated by KIOM-4. KIOM-4 prevented STZ-induced mitochondrial lipid peroxidation, protein carbonyl and DNA modification. Moreover, KIOM-4 treatment restored the loss of mitochondrial membrane potential (Δψ) that was induced by STZ treatment, and inhibited the translocation of cytochrome c from the mitochondria to the cytosol. In addition, KIOM-4 treatment elevated the level of ATP, succinate dehydrogenase activity and insulin level, which were reduced by STZ treatment. These results suggest that KIOM-4 exhibits a protective effect through its antioxidant effect and the attenuation of mitochondrial dysfunction in STZ-induced diabetic cells.

Empetrum nigrum var. japonicum extract suppresses γ-ray radiation-induced cell damage via inhibition of oxidative stress.

The ethylacetate fraction of Empetrum nigrum var. japonicum (ENE) was shown to reduce intracellular reactive oxygen species (ROS) generated by γ-radiation and activate antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and gluthathion peroxidase (GPx). ENE protected cells against radiation-induced cellular DNA damage, membrane lipid peroxidation, and protein modification, which are the main points of radiation-induced damage. In addition, ENE recovered cell viability by inhibiting apoptosis after cells were treated with radiation. ENE treatment also reduced γ-radiation induced Bax, and caspase 9 and 3 expression in irradiated cells. However, irradiated cells with ENE recovered Bcl-2 expression, which was reduced by radiation. This anti-apoptotic effect of ENE was due to the inhibition of mitogen-activated protein kinase kinase-4 (MKK4/SEK1)-c-Jun NH(2)-terminal kinase (JNK) cascades induced by γ-radiation. In summary, these results suggest that ENE protects cells against γ-radiation-induced oxidative stress via the reduction of ROS and attenuation of apoptosis.

Cytoprotective effects of triphlorethol-A against formaldehyde-induced oxidative damage and apoptosis: role of mitochondria-mediated caspase-dependent pathway.

The toxicity of formaldehyde (HCHO) has been attributed to its ability to form adducts with DNA and proteins. Triphlorethol-A, derived from Ecklonia cava, was reported to exert a cytoprotective effect against oxidative stress damage via an antioxidant mechanism. The aim of this study was to examine the mechanisms underlying the triphlorethol-A ability to protect Chinese hamster lung fibroblast (V79-4) cells against HCHO-induced damage. Triphlorethol-A significantly decreased the HCHO-induced intracellular reactive oxygen species (ROS) production. Triphlorethol-A prevented increased cell damage induced by HCHO via inhibition of mitochondria-mediated caspase-dependent apoptosis pathway. Triphlorethol-A diminished HCHO-induced mitochondrial dysfunction, including loss of mitochondrial membrane action potential (Δψ) and adenosine triphosphate (ATP) depletion. Furthermore, the anti-apoptotic effect of triphlorethol-A was exerted through inhibition of c-Jun NH(2)-terminal kinase (JNK), which was enhanced by HCHO. Our data indicate that triphlorethol-A exerts a cytoprotective effect in V79-4 cells against HCHO-induced oxidative stress by inhibiting the mitochondria-mediated caspase-dependent apoptotic pathway.

Compound K, a metabolite of ginseng saponin, induces mitochondria-dependent and caspase-dependent apoptosis via the generation of reactive oxygen species in human colon cancer cells.

The objective of this study was to elucidate the cytotoxic mechanism of Compound K, with respect to the involvement of reactive oxygen species (ROS) and the mitochondrial involved apoptosis, in HT-29 human colon cancer cells. Compound K exhibited a concentration of 50% growth inhibition (IC(50)) at 20 µg/mL and cytotoxicity in a time dependent manner. Compound K produced intracellular ROS in a time dependent fashion; however, N-acetylcysteine (NAC) pretreatment resulted in the inhibition of this effect and the recovery of cell viability. Compound K induced a mitochondria-dependent apoptotic pathway via the modulation of Bax and Bcl-2 expressions, resulting in the disruption of the mitochondrial membrane potential (Δψ(m)). Loss of the Δψ(m) was followed by cytochrome c release from the mitochondria, resulting in the activation of caspase-9, -3, and concomitant poly ADP-ribosyl polymerase (PARP) cleavage, which are the indicators of caspase-dependent apoptosis. The apoptotic effect of Compound K, exerted via the activation of c-Jun NH(2)-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK), was abrogated by specific MAPK inhibitors. This study demonstrated that Compound K-mediated generation of ROS led to apoptosis through the modulation of a mitochondria-dependent apoptotic pathway and MAPK pathway.

Antibiotic treatment of Mycobacterium abscessus lung disease: a retrospective analysis of 65 patients.

RATIONALE: The optimal therapeutic regimen and duration of treatment for Mycobacterium abscessus lung disease is not well established. OBJECTIVES: To assess the efficacy of a standardized combination antibiotic therapy for the treatment of M. abscessus lung disease. METHODS: Sixty-five patients (11 males, 55 females, median age 55 yr) with M. abscessus lung disease were treated with clarithromycin, ciprofloxacin, and doxycycline, together with an initial regimen of amikacin and cefoxitin for the first 4 weeks of hospitalization. MEASUREMENTS AND MAIN RESULTS: Treatment response rates were 83% for symptoms and 74% for high-resolution computed tomography. Sputum conversion and maintenance of negative sputum cultures for more than 12 months was achieved in 38 (58%) patients. These rates were significantly lower in patients whose isolates were resistant to clarithromycin (17%, 2/12) compared with those whose isolates were susceptible or intermediate to clarithromycin (64%, 21/33; P = 0.007). Neutropenia and thrombocytopenia associated with cefoxitin developed in 33 (51%) and 4 (6%) patients, respectively. Drug-induced hepatotoxicity occurred in 10 (15%) patients. Because of these adverse reactions, cefoxitin was discontinued in 39 (60%) patients after treatment for a median of 22 days. CONCLUSIONS: Standardized combination antibiotic therapy was moderately effective in treating M. abscessus lung disease. However, frequent adverse reactions and the potential for long-duration hospitalization are important problems that remain to be solved.

Rhapontigenin from Rheum undulatum protects against oxidative-stress-induced cell damage through antioxidant activity.

The antioxidant properties of rhapontigenin and rhaponticin isolated from Rheum undulatum were investigated. Rhapontigenin was found to scavenge intracellular reactive oxygen species (ROS), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and hydrogen peroxide (H2O2). The radical scavenging effect of rhapontigenin was more effective than rhaponticin. Rhapontigenin protected against H2O2-induced membrane lipid peroxidation and cellular DNA damage, which are the main targets of oxidative stress-induced cellular damage. The radical scavenging activity of rhapontigenin protected Chinese hamster lung fibroblast (V79-4) cells exposed to H2O2 by inhibiting apoptosis. Rhapontigenin inhibited cell damage induced by serum starvation and was also found to increase the activity of catalase and its protein expression. Further, rhapontigenin increased phosphorylation of extracellular signal-regulated kinase (ERK) and inhibited the activity of activator protein 1 (AP-1), a redox-sensitive transcription factor. In summary, these results suggest that rhapontigenin protects V79-4 cells against oxidative damage by enhancing the cellular antioxidant activity and modulating cellular signal pathways.

Inhibitory effects of glycitein on hydrogen peroxide induced cell damage by scavenging reactive oxygen species and inhibiting c-Jun N-terminal kinase.

The present study investigated the cytoprotective properties of glycitein, a metabolite formed by the transformation of glycitin by intestinal microflora, against oxidative stress. Glycitein was found to scavenge intracellular reactive oxygen species (ROS), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and thereby preventing lipid peroxidation and DNA damage. Glycitein inhibited apoptosis of Chinese hamster lung fibroblast (V79-4) cells exposed to hydrogen peroxide (H(2)O(2)) via radical scavenging activity. Glycitein abrogated the activation of c-Jun N-terminal kinase (JNK) induced by H(2)O(2) treatment and inhibited DNA binding activity of activator protein-1 (AP-1), a downstream transcription factor of JNK. Taken together, these findings suggest that glycitein protected H(2)O(2) induced cell death in V79-4 cells by inhibiting ROS generation and JNK activation.

Differentiation of Streptomyces spp. which cause potato scab disease on the basis of partial rpoB gene sequences.

In a previous study, we found that the phylogenetic analysis of partial rpoB sequences can be used effectively to phylogenetically differentiate Streptomyces spp. [B.J. Kim, C.J. Kim, J. Chun, Y.H. Koh, S.H. Lee, J.W. Hyun, C.Y. Cha, Y.H. Kook, Phylogenetic analysis of the genera Streptomyces and Kitasatospora based on partial RNA polymerase beta-subunit gene (rpoB) sequences, Int. J. Syst. Evol. Microbiol. 54 (2004) 593-598]. In the present study, we analyzed the partial rpoB gene sequences of 19 reference Streptomyces strains associated with potato scab. Furthermore, to empirically confirm the usefulness of rpoB gene analysis for the phylogenetic differentiation of Streptomyces spp., we applied the proposed system to 27 potato scab isolates obtained from the Korean provinces of Jeju-do and Kangwon-do. Phylogenetic relationships among these isolates using the devised rpoB gene-based methods were generally similar to those reported for 16S rRNA gene-based analysis. Isolates from potato scab lesion in Korea were also clearly differentiated into their phylogenetic groups by this method. In addition, the deduced RpoB amino acid sequences were also found to be useful for differentiating these strains. Our data demonstrate that the rpoB gene-based method can be used as a means of complementing other genetic methods such as 16S rRNA gene analysis or DNA-DNA hybridization to phylogenetically differentiate potato scab related Streptomyces spp.