Effect of CYP2C9*3 mutant variants on meloxicam pharmacokinetics in a healthy Chinese population

The aim of this study was to investigate the effect of the CYP2C9*3 (CYP2C9 1075 A>C) polymorphism on meloxicam pharmacokinetics in a Chinese population. Twenty-four healthy volunteers were enrolled in this study. The pyrosequencing technique was used to identify polymorphisms of CYP2C9. The concentration of meloxicam in plasma was determined by a high-performance liquid chromatography assay with mass spectrographic analysis. The Drug and Statistics Software (DAS, version 2.0) was used for curve fitting and calculations of pharmacokinetic parameters. The effects of CYP2C9*3 variant genotypes on meloxicam pharmacokinetics were compared with those of the wild type genotype. Among the 24 volunteers, two AC heterozygotes were observed in the multi-dose group. CYP2C9*3 was found to play an important role in the metabolism of meloxicam by reducing its enzymatic activity. Therefore, results of this study provide helpful information regarding inter-individual pharmacokinetic variability in the Chinese population.

Multicenter, double-blind, randomized clinical trial of parenterally administered Cefoselis versus Cefepime for the treatment of acute bacterial infections

AIM

This study aims to evaluate the clinical efficacy and safety of intravenous Cefoselis injection for the treatment of acute moderate and severe bacterial infections.

PATIENTS AND METHODS

A multicenter, double-blind, randomized clinical trial was carried out using Cefepime as control. Patients received 1.0 g of either Cefoselis or Cefepime for moderate infections or 2.0 g for severe infections at an interval of 12 hours for 7 to 14 days. A total of 276 patients (138 with Cefoselis, 138 with Cefepime) with respiratory or urinary tract infections were enrolled in the study. Up to 137 and 124 patients receiving Cefoselis and 132 and 125 patients receiving Cefepime were eligible for the ITT (intent to treat) and PP (per protocol) analyses, respectively.

RESULTS

At the end of the treatment, the cure rates and effective rates were 59.68% (74/124) and 93.55% (116/124) with Cefoselis, and 56.00% (74/124) and 90.40% (116/124) with Cefepime. The bacterial eradication rates of the two groups were 90.32% and 93.85%, respectively. No statistical differences were observed on the above-mentioned parameters between the two groups (all p > 0.05). Adverse events, mainly mild aminotransferase elevation and mild leukopenia, were observed in 11.59% (16/138) and 13.77% (19/138) of patients with Cefoselis and Cefepime, respectively (p > 0.05).

CONCLUSIONS

Cefoselis is an effective and safe choice against acute moderate and severe respiratory infections and UTI (urinary tract infection).

First Report of Corynespora cassiicola Causing Leaf Spot on Akebia trifoliate

Akebia species have been used for centuries in medicinal practices in a few Asian countries such as China and Japan. The dried stems of Akebia trifoliata are known as mutong in the Chinese pharmacopoeia (4) and mokutsu in Kampo, the traditional Chinese medicine developed in Japan (2). In China, the plant is grown in the provinces of Shandong, Hebei, Shanxi, Henan, Gansu, and some provinces in the south of the Yangtze River basin. During the summer of 2012, a leaf spot disease was detected on A. trifoliata grown in Nanning, Guangxi, China. The disease occurred and spread rapidly in July under conditions of high temperature and high humidity. The symptoms appeared on three sites that we inspected; disease incidences were higher than 80%. Initial symptoms consisted of small (less than 5 mm in diameter), circular, purple-brown leaf spots. Spots later enlarged and became elliptical, circular, or irregular with gray-white centers and dark brown rims. The centers were slightly concave. The spots could coalesce with each other, resulting in leaf desiccation and wilting. A fungal isolate was obtained from symptomatic leaf tissue that taken from a field (22°50'N, 108°22'E) in Nanning, Guangxi, China. Single-spore culture of the isolate was incubated on potato dextrose agar (PDA) for 7 days in the dark at 28°C. Conidiophores were straight to slightly curved, unbranched, and pale brown. Conidia (19.0 to 140.5 μm long and 7.0 to 11.0 μm wide) were formed singly or in chains, obclavate to cylindrical, straight or curved, pale brown, with a rounded apex and truncate base, and 1 to 13 pseudosepta. Morphological characteristics of the isolate were similar to the descriptions of Corynespora cassiicola (Berk. & M.A. Curtis) C.T. Wei (1). Genomic DNA of the isolate was extracted and used for PCR amplification of rDNA-ITS (internal transcribed spacer) sequence with primers ITS1 and ITS4. The PCR products were purified and sequenced. The sequence (GenBank Accession No. KC977496) was used in BLAST searches to interrogate GenBank for sequence similarity. High sequence similarity of 100% was obtained with several C. cassiicola strains. Pathogenicity of the isolate was investigated to demonstrate Koch's postulate. Young, healthy, fully expanded green leaves of A. trifoliata were surface sterilized. Fifteen leaves were inoculated with 10-μl drops of conidia suspension (10⁵ conidia per ml) and 10 leaves were inoculated with the same volume of sterile water to serve as controls. All the leaves were placed in a humid chamber for 5 days. Spots with similar symptoms to those observed in the field developed on all inoculated leaves. The pathogen was reisolated and identified as C. cassiicola. The controls remained symptomless. According to previous reports, A. trifoliata was infected by Alternaria tenuissima in China and by Colletotrichum acutatum in Japan (3). To our knowledge, this is the first report of C. cassiicola found on Akebia species worldwide. Furthermore, this new disease primarily affects plantations and reduces the quality and yield of the medicine. Some effective measures should be taken to control this disease. References: (1) M. B. Ellis and P. Holliday. CMI Description of Pathogenic Fungi and Bacteria, 303, 1971. (2) F. Kitaoka et al. J. Nat. Med. 63:374, 2009. (3) Y. Kobayshi et al. J. Gen. Plant Pathol. 70:295, 2004. (4) L. Li et al. HortScience 45:4, 2010.

Effect of inhibition of MEK pathway on 5-aza-deoxycytidine-suppressed pancreatic cancer cell proliferation

Pancreatic adenocarcinoma is a lethal disease because it is inoperable at the time of diagnosis. Therefore, the search for new therapeutic approaches is critical. The abnormal expression of the mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK) pathway and alteration in epigenetic modification (DNA methylation and acetylation of histones) is a common feature in the majority of human pancreatic adenocarcinomas. Because DNA methyltransferase levels are regulated by the MEK pathway, we examined the effects of an MEK inhibitor, PD98059, on the action of DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-dC), the epigenetic agent in the pancreatic cell line CFPAC1. Our results showed that PD98059 significantly potentiated the capability of 5-aza-dC to induce a cessation of cell proliferation concomitant with cell cycle arrest. We also observed an increase in tumor suppressor gene expression associated with the efficacy of treatment with PD98059 and 5-aza-dC. Further studies explored the molecular mechanisms by which 5-aza-dC induced the expression of p21(WAF1). We found that 5-aza-dC induced acetylation of histone H3 on the p21(WAF1) gene promoter and demethylation status on the p21(WAF1) gene promoter region. These effects were strikingly enhanced by the concomitant blockade of the MEK pathway. Furthermore, knockdown of p21(WAF1) by small interfering RNA rescued human pancreatic cancer cells from 5-aza-dC-mediated growth inhibition. Taken together, our results show that the MEK inhibitor enhanced the effects of 5-aza-dC in human pancreatic cancer cells. These results suggest that the MEK signal pathway may be a potential target for pancreatic cancer therapy.

Enhanced minority carrier lifetimes in GaAs/AlGaAs core-shell nanowires through shell growth optimization

The effects of AlGaAs shell thickness and growth time on the minority carrier lifetime in the GaAs core of GaAs/AlGaAs core-shell nanowires grown by metal-organic chemical vapor deposition are investigated. The carrier lifetime increases with increasing AlGaAs shell thickness up to a certain value as a result of reducing tunneling probability of carriers through the AlGaAs shell, beyond which the carrier lifetime reduces due to the diffusion of Ga-Al and/or impurities across the GaAs/AlGaAs heterointerface. Interdiffusion at the heterointerface is observed directly using high-angle annular dark field scanning transmission electron microscopy. We achieve room temperature minority carrier lifetimes of 1.9 ns by optimizing the shell growth with the intention of reducing the effect of interdiffusion.

Valosin-containing protein regulates the proteasome-mediated degradation of DNA-PKcs in glioma cells

DNA-dependent protein kinase (DNA-PK) has an important role in the repair of DNA damage and regulates the radiation sensitivity of glioblastoma cells. The VCP (valosine-containing protein), a chaperone protein that regulates ubiquitin-dependent protein degradation, is phosphorylated by DNA-PK and recruited to DNA double-strand break sites to regulate DNA damage repair. However, it is not clear whether VCP is involved in DNA-PKcs (DNA-PK catalytic subunit) degradation or whether it regulates the radiosensitivity of glioblastoma. Our data demonstrated that DNA-PKcs was ubiquitinated and bound to VCP. VCP knockdown resulted in the accumulation of the DNA-PKcs protein in glioblastoma cells, and the proteasome inhibitor MG132 synergised this increase. As expected, this increase promoted the efficiency of DNA repair in several glioblastoma cell lines; in turn, this enhanced activity decreased the radiation sensitivity and prolonged the survival fraction of glioblastoma cells in vitro. Moreover, the VCP knockdown in glioblastoma cells reduced the survival time of the xenografted mice with radiation treatment relative to the control xenografted glioblastoma mice. In addition, the VCP protein was also downregulated in ∼25% of GBM tissues from patients (WHO, grade IV astrocytoma), and the VCP protein level was correlated with patient survival (R²=0.5222, P<0.05). These findings demonstrated that VCP regulates DNA-PKcs degradation and increases the sensitivity of GBM cells to radiation.

First Report of Leaf Spot Caused by Alternaria porri on Velvet Bean (Mucuna pruriens) in China

Mucuna pruriens is a tropical legume known as velvet bean. It has many traditional and medicinal usages in treating Parkinson's disease (1), abdominal pain, cholera, infertility, scorpion bites, diabetes (3) and is found in tropical Africa, India, the Caribbean and China. During the fall of 2011, the velvet bean plants in Longan County, Guangxi, China, were damaged by a leaf disease previously unreported in China. Field inspections revealed disease incidences as high as 80%. Symptoms consisted of large spots developing between the leaf veins that ranged in length from 1 to 3 cm. Spots were dark brown, generally rectangular, and were visible from both sides of the leaf. Lots of black mycelia and conidia were found on the backs of the lesions. Lesions typically expanded and affected the entire leaf, resulting in leaves withered and killed. An Alternaria sp. having conidia with prominent beaks and spores produced singly was consistently observed on and isolated from symptomatic leaf tissue. The conidia body was brown, ovoid, obclavate, muriform, and septate, with transverse and longitudinal septa that varied from 6 to 9 and 0 to 2, respectively, and its dimensions varied from 60 to 120 × 15 to 20 μm. The beaks were 10 to 70 × 3 to 6 μm and were filamentous, slender, and unbranched. Pure culture of the fungus was made from a single spore. DNA was extracted and used in an internal transcribed spacer (ITS) PCR used ITS1 and ITS4 primers. The PCR products were purified and sequenced. The sequences were used in BLAST searches to interrogate the GenBank for sequence similarity. High sequence similarity of 100% was obtained with Alternaria porri isolate AP-18. Based on the morphological and molecular characterization, the isolate was identified as A. porri (Ellis) Ciferri (GenBank Accession No. JX556683) (2). The pathogenicity of five isolates was investigated to demonstrate Koch's postulates. Forty 8-week-old seedlings of M. pruriens, without wounding on their leaves, were sprayed with the spore suspension (10⁵ spores per ml), prepared by using 10-day-old cultures of the isolates grown on potato dextrose agar at 28°C in the dark. Every plant was sprayed with 4 ml of spore suspension. The inoculated plants were incubated in a humid chamber for 48 h and then maintained in a greenhouse. After 5 to 7 days, leaf spots similar to those observed in the field developed on all inoculated plants. The pathogen was reisolated and identified as A. porri. Control plants sprayed with distilled water remained symptomless. The inoculation test was repeated and results were the same. Because A. porri was reported to infect plants of Allium spp and cause purple blotch, we also inoculated this isolate to small onion plants, and the symptoms of purple blotch appeared after 13 days at 25 to 28°C in a greenhouse. To our knowledge, this is the first report of leaf spot caused by A. porri on velvet bean in China. References: (1) R. Katzenschlager et al. J. Neurol. Neurosurg Psychiatry. 75:1672, 2004. (2) S. T. Koike and D. H. Henderson. Plant Dis. 82:710, 1998. (3) S. O. Majekodunmi et al. Asian Pac. J. Trop. Med. 4:632, 2011.

Molecular cloning and functional characterization of a mouse ccl6 analog gene in the rat

Suppression subtractive hybridization was used to analyze differential expression of genes in rat peritoneal macrophages after granulocyte macrophage colony-stimulating factor treatment. We identified and cloned the mouse C10 analog gene in the rat, and named it as ccl6. The full-length cDNA of rat ccl6 was 467 bp, which contains a single-open reading frame and encodes 116 amino acid residues. Compared with other C-C chemokines, the rat ccl6 gene had an unusual four-exon genome structure instead of the typical three exons, it had the highest homology with murine ccl6. The rat ccl6 gene was localized on chromosome 10, where most of the C-C chemokine superfamily members are located. The recombinant rat C-C chemokine ligand 6 (CCL6) protein was expressed by the pGEX4T-1 plasmid in Escherichia coli BL21. The purified recombinant protein had bioactivity similar to that of mouse CCL6, which is a chemoattractant for macrophages and lymphocytes, but not for neutrophils.

Observation of multiple vibrational modes in ultrahigh vacuum tip-enhanced Raman spectroscopy combined with molecular-resolution scanning tunneling microscopy

Multiple vibrational modes have been observed for copper phthalocyanine (CuPc) adlayers on Ag(111) using ultrahigh vacuum (UHV) tip-enhanced Raman spectroscopy (TERS). Several important new experimental features are introduced in this work that significantly advance the state-of-the-art in UHV-TERS. These include (1) concurrent sub-nm molecular resolution STM imaging using Ag tips with laser illumination of the tip-sample junction, (2) laser focusing and Raman collection optics that are external to the UHV-STM that has two cryoshrouds for future low temperature experiments, and (3) all sample preparation steps are carried out in UHV to minimize contamination and maximize spatial resolution. Using this apparatus we have been able to demonstrate a TERS enhancement factor of 7.1 × 10(5). Further, density-functional theory calculations have been carried out that allow quantitative identification of eight different vibrational modes in the TER spectra. The combination of molecular-resolution UHV-STM imaging with the detailed chemical information content of UHV-TERS allows the interactions between large polyatomic molecular adsorbates and specific binding sites on solid surfaces to be probed with unprecedented spatial and spectroscopic resolution.

Direct-write non-linear photolithography for semiconductor nanowire characterization

A practical bottleneck prohibiting the rapid, confident and damage-free electrical contacting of vapour-liquid-solid grown nanowires arises from the random spatial distribution and variation in quality of the nanowires, and the contact dimensions required. Established techniques such as electron-beam lithography or focused ion-beam deposition have challenges in scaling, damage or complexity that can make a large statistical sample difficult. We present a direct laser-writing technique to allow rapid electrical contacting of nanowires on a large variety of substrates.

LivBioSig: development of a toolbox for online bio-signals processing and experimentation

Various research fields, such as brain computer interface, requires online acquisition and analysis of biological data to validate assumptions or to help obtaining insights into the physiological processes of the human body. In this paper we introduce the LivBioSig toolbox for online bio-signals processing and experimentation. This open source and modularized MATLAB toolbox allows performing various experiment paradigms involving online signal processing. These currently include synchronous and asynchronous BCI experiments, and event related stimulation experiments. The use of Graphic User Interfaces (GUI) makes the system suitable even for beginner Matlab users, and the experiments easily configurable. The modularized structure allows advanced users to develop the toolbox further to adapt it to the needs of the research fields.

Impact of an irreversibly adsorbed layer on local viscosity of nanoconfined polymer melts

We report the origin of the effect of nanoscale confinement on the local viscosity of entangled polystyrene (PS) films at temperatures far above the glass transition temperature. By using marker x-ray photon correlation spectroscopy with gold nanoparticles embedded in the PS films prepared on solid substrates, we have determined the local viscosity as a function of the distance from the polymer-substrate interface. The results show the impact of a very thin adsorbed layer (~7 nm in thickness) even without specific interactions of the polymer with the substrate, overcoming the effect of a surface mobile layer at the air-polymer interface and thereby resulting in a significant increase in the local viscosity as approaching the substrate interface.

Targeted gene silencing of TLR4 using liposomal nanoparticles for preventing liver ischemia reperfusion injury

RNAi-based therapy is a promising strategy for the prevention of ischemia-reperfusion injury (IRI). However, systemic administration of small interfering RNA (siRNA) may cause globally nonspecific targeting of all tissues, which impedes clinical use. Here we report a hepatocyte-specific delivery system for the treatment of liver IRI, using galactose-conjugated liposome nanoparticles (Gal-LipoNP). Heptocyte-specific targeting was validated by selective in vivo delivery as observed by increased Gal-LipoNP accumulation and gene silencing in the liver. Gal-LipoNP TLR4 siRNA treatment resulted in a significant decrease of serum alanine transferase (ALT) and aspartate transaminase (AST) in a hepatic IRI model. Histopathology displayed an overall reduction of the injury area in the Gal-LipoNP TLR4 siRNA treated mice. Additionally, neutrophil accumulation and lipid peroxidase-mediated tissue injury, detected by MPO, MDA and ROS respectively, were attenuated after Gal-LipoNP TLR4 siRNA treatment. Moreover, therapeutic effects of Gal-LipoNP TLR4 siRNA were associated with suppression of the inflammatory cytokines IL-1 and TNF-α. Taken together, this study is the first demonstration of liver IRI treatment using liver-specific siRNA delivery.