In vivo emergence of a novel mutant L159F/L320F in the NS5B polymerase confers low-level resistance to the HCV polymerase inhibitors mericitabine and sofosbuvir.

BACKGROUND: Resistance to mericitabine (prodrug of HCV NS5B polymerase inhibitor PSI-6130) is rare and conferred by the NS5B S282T mutation. METHODS: Serum HCV RNA from patients who experienced viral breakthrough, partial response, or nonresponse in 2 clinical trials in which patients received mericitabine plus peginterferon alfa-2a (40KD)/ribavirin were analyzed by population and clonal sequence analysis as well as phenotypic assay for assessment of in vivo mericitabine resistance. RESULTS: Among 405 patients treated with mericitabine plus peginterferon alfa-2a/ribavirin in PROPEL and JUMP-C, virologic breakthrough or nonresponse were not observed; 12 patients experienced a partial response. The NS5B S282T resistance mutation was not observed in any patient. A number of treatment-associated NS5B changes were observed and characterized. A novel double mutant (L159F/L320F) with impaired replication capacity was detected in one HCV genotype 1b-infected patient. Introduction of double mutant L159F/L320F into genotype 1a (H77) and 1b (Con-1) replicons, respectively, increased the EC50 for mericitabine by 3.1- and 5.5-fold and the EC90 by 3.1- and 8.9-fold. The double mutant also decreased susceptibility to sofosbuvir (GS-7977) and GS-938 but not setrobuvir, relative to wild-type. CONCLUSIONS: A novel and replication-deficient double mutation (L159F/L320F) confers low-level resistance to mericitabine and cross-resistance to both sofosbuvir and GS-938. CLINICAL TRIALS REGISTRATION: NCT00869661, NCT01057667.

A new species of Siphlonurus Eaton, 1868 (Ephemeroptera, Siphlonuridae) from Yunnan, China.

Siphlonurusdongxi Li & Tong, sp. nov. from Shangri-La City, Yunnan Province, China, is described based on egg, nymph, and winged stages. The new species is closely related to S.davidi (Navás, 1932), and can be distinguished by the colour of the imago, the forking point of MP, the penis, posterolateral spines of tergum IX of imagoes, and first abdominal terga nymph, as well as the structure of the egg. The new species and S.davidi have the same morphological and structural characteristics, such as the long cubital area with many intercalaries, cross veins between C, Sc, RA, and RSa1 surrounded with distinct pigments, the strong curvature of vein CuP in the forewing, the broad expansion of the hindwing, the membranous penis lobes fused without teeth, supporting the proposition of a new species complex, the Siphlonurusdavidi group. The structures of the penis and the egg of the new species could help understand the origin and evolution of the genus Siphlonurus.

Stretchable Photodiodes with Polymer-Engineered Semiconductor Nanowires for Wearable Photoplethysmography.

Healthcare systems worldwide have been stressed to provide sufficient resources to serve the increasing and aging population in our society. The situation became more challenging at the time of pandemic. Technology advancement, especially the adoption of wearable health monitoring devices, has provided an important supplement to current clinical equipment. Most health monitoring devices are rigid, however, human tissues are soft. Such a difference has prohibited intimate contact between the two and jeopardized wearing comfortableness, which hurdles measurement accuracy especially during longtime usage. Here, we report a soft and stretchable photodiode that can conformally adhere onto the human body without any pressure and measure cardiovascular variables for an extended period with higher reliability than commercial devices. The photodiode used a composite light absorber consisting of an organic bulk heterojunction embedded into an elastic polymer matrix. It is discovered that the elastic polymer matrix not only improves the morphology of the bulk heterojunction for obtaining the desired mechanical properties but also alters its electronic band structure and improves the electrical properties that lead to a reduced dark current and enhanced photovoltage in the stretchable photodiode. The work has demonstrated high fidelity measurements and longtime monitoring of heat rate variability and oxygen saturation, potentially enabling next-generation wearable photoplethysmography devices for point-of-care diagnosis of cardiovascular diseases in a more accessible and affordable way.

Antiviral activity of narlaprevir combined with ritonavir and pegylated interferon in chronic hepatitis C patients.

UNLABELLED: Narlaprevir (SCH 900518) is a potent inhibitor of the hepatitis C virus (HCV) nonstructural protein 3 serine protease that is primarily metabolized by the cytochrome P450-3A4 system. In order to explore the use of ritonavir-based pharmacokinetic enhancement of an HCV protease inhibitor, this study investigated the safety, tolerability, pharmacokinetics, and antiviral activity of narlaprevir (with or without ritonavir) administered as monotherapy and as combination therapy with pegylated interferon-α-2b (PEG-IFN-α-2b) to HCV genotype 1-infected patients. This was a randomized, placebo-controlled, two-period, blinded study in 40 HCV genotype 1-infected patients (naïve and treatment-experienced). In period 1, narlaprevir was administered for 7 days as 800 mg three times daily without ritonavir or 400 mg twice daily with 200 mg ritonavir twice daily. In period 2, after a 4-week washout, the same dose and regimen of narlaprevir was administered in combination with PEG-IFN-α-2b for 14 days. Upon completion of period 2, all patients initiated PEG-IFN-α-2b and ribavirin treatment. A rapid and persistent decline in plasma HCV-RNA was observed in both treatment-experienced and treatment-naïve patients during period 1, with a mean viral load decline of at least 4 log10 in all treatment groups. A high percentage of both treatment-experienced (50%) and treatment-naïve (≥ 60%) patients had undetectable HCV-RNA (< 25 IU/mL) after period 2. Standard of care resulted in sustained virological response (SVR) rates of 38% and 81% in treatment-experienced and treatment-naïve patients, respectively. Narlaprevir (with or without ritonavir) alone or in combination with PEG-IFN-α-2b was safe and well tolerated. CONCLUSION: Narlaprevir administration resulted in a robust HCV-RNA decline and high SVR rates when followed by standard of care in both treatment-experienced and treatment-naïve HCV genotype 1-infected patients.

Polyol pathway impairs the function of SERCA and RyR in ischemic-reperfused rat hearts by increasing oxidative modifications of these proteins.

A number of studies have shown that the polyol pathway, consisting of aldose reductase (AR) and sorbitol dehydrogenase (SDH), contributes to ischemia-reperfusion (I/R)-induced myocardial infarction due to depletion of ATP. In this report we show that the polyol pathway in I/R heart also contributes to the impairment of sacro/endoplasmic reticulum Ca(2+)-ATPase (SERCA) and ryanodine receptor (RyR), two key players in Ca(2+) signaling that regulate cardiac contraction. Rat hearts were isolated and retrogradely perfused with either Krebs' buffer containing 1 microM AR inhibitor, zopolrestat, or 200 nM SDH inhibitor, CP-170,711, and challenged by 30 min of regional ischemia and 45 min of reperfusion. We found that post-ischemic contractile function of the isolated perfused hearts was improved by pharmacological inhibition of the polyol pathway. I/R-induced contractile dysfunction is most likely due to impairment in Ca(2+) signaling and the activities of SERCA and RyR. All these abnormalities were significantly ameliorated by treatment with ARI or SDI. We showed that the polyol pathway activities increase the level of peroxynitrite, which enhances the tyrosine nitration of SERCA and irreversibly modifies it to form SERCAC674-SO(3)H. This leads to reduced level of S-glutathiolated SERCA, contributing to its inactivation. The polyol pathway activities also deplete the level of GSH, leading to decreased active RyR, the S-glutathiolated RyR. Thus, in I/R heart, inhibition of polyol pathway improved the function of SERCA and RyR by protecting them from irreversible oxidation.

Polydopamine Surface Coating Synergizes the Antimicrobial Activity of Silver Nanoparticles.

Metal nanoparticles, especially silver nanoparticles (AgNPs), have drawn increasing attention for antimicrobial applications. Most studies have emphasized on the correlations between the antibacterial potency of AgNPs and the kinetics of metallic to ionic Ag conversion, while other antimicrobial mechanisms have been underestimated. In this work, we focused on the surface effects of polydopamine (PDA) coating on the antimicrobial activity of AgNPs. A method of fast deposition of PDA was used to synthesize the PDA-AgNPs with controllable coating thickness ranging from 3 to 25 nm. The antimicrobial activities of the PDA-AgNPs were analyzed by fluorescence-based growth curve assays on Escherichia coli. The results indicated that the PDA-AgNPs exhibited significantly higher antibacterial activities than poly(vinylpyrrolidone)-passivated AgNPs (PVP-AgNPs) and PDA themselves. It was found that the PDA coating synergized with the AgNPs to prominently enhance the potency of the PDA-AgNPs against bacteria. The analysis of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy elucidated that the synergistic effects could be originated from the interaction/coordination between Ag and catechol group on the PDA coating. The synergistic effects led to increased generation of reactive oxygen species and the consequent bacterial damage. These findings demonstrated the importance of the surface effects on the antimicrobial properties of AgNPs. The underlying molecular mechanisms have shined light on the future development of more potent metal nanoparticle-based antimicrobial agents.

Artemisinin is highly soluble in polyethylene Glycol 4000 and such solution has multiple biological effects.

Artemisinin has a significant role in treatment of malaria, as well as effective anti-inflammatory and anti-cancer activities. However, such problems as poor water solubility and easy recrystallization limit its application. In this study, polyethylene glycol, a solvent which is widely used in pharmaceutics, was introduced to prepare an artemisinin dissolution. Under the action of hydrogen bonding in 12% polyethylene glycol 4000 solvent, the maximum solubility of artemisinin could reach up to 1 mg/mL. Meanwhile, biological functions of such artemisinin solution were evaluated. The obtained artemisinin solution had a significant inhibitory effect on Gram-positive bacteria, Gram-negative bacteria and fungi. As for the anti-inflammatory property, 0.031 mg/mL artemisinin solution had an obvious inhibitory effect on nitric oxide release in inflammatory cells, and the survival rate of cells was greater than 50%. Low concentration of the obtained artemisinin solution (0.031 mg/mL) had no significant cytotoxicity, while it displayed selective inhibition in cancer cells. IC50 for human hepatoma cells BEL-7404, SMMC7721 and Hep G2 is 0.0016 mg/mL, 0.0084 mg/mL and 0.0541 mg/mL, respectively. In conclusion, the 12% PEG4000-assisted artemisinin solution has a good biological effect and it can be further applied in pharmaceutics, biomaterials and medicine.

Tuning the framework topologies of Co(II)-doped Zn(II)-tetrazole-benzoate coordination polymers by ligand modifications: structures and spectral studies.

In our continuing efforts to explore the effects of ligand modifications on the structures and properties of their metal complexes, we studied the in situ [2 + 3] cycloaddition reactions of benzonitrile, o-phthalodinitrile, 3-cyanobenzoic acid, 4-cyanobenzoic acid with NaN(3) in the presence of Zn(II) and/or Co(II) salts under hydrothermal conditions, and obtained four new Co(II)-doped Zn(II)-tetrazole-benzoate coordination polymers with the formula of [Co(x)Zn(1-x)(L(m))(y)](n) [5-phenyl-1H-tetrazole (HL(1)) for 1, 2-(1H-tetrazol-5-yl)benzoic acid (H(2)L(2)) for 2, 3-(1H-tetrazol-5-yl)benzoic acid (H(2)L(3)) for 3, and 4-(1H-tetrazol-5-yl)benzoic acid (H(2)L(4)) for 4]. The structure of 1 shows a classical diamondoid net, while 2 and 3, take 2D layer structure with (4.6(2))(4.6.4.6) topology and 3D SrAl(2) topology, respectively. The structure of 4 exhibits a four-connected 3D network with rare non-diamondoid 6(6) topology. The coordination modes of the center metal and the ligands in the four complexes are almost the same, being tetrahedral or four-connected, but their topologies are quite different. Thus, the four structurally related ligands allow analysis of the effects of the disposition of a second functional carboxylate group on an aromatic ring and the twist angles of the carboxylate and tetrazoyl out of the plane of the aromatic ring on the overall structural topology of their complexes. Interestingly, the Co(II) ions were doped into the Zn(II) complexes, as confirmed by their macroscopical colors, inductively coupled plasma (ICP) analysis and UV-visible spectra. In addition, the photoluminescence of the four complexes in the solid state at room temperature was briefly studied.

Sensitive Deep Ultraviolet Photodetector and Image Sensor Composed of Inorganic Lead-Free Cs3Cu2I5 Perovskite with Wide Bandgap.

In this work, a sensitive deep ultraviolet (DUV) light photodetector based on inorganic and lead-free Cs3Cu2I5 crystalline film derived by a solution method was reported. Optoelectronic characterization revealed that the perovskite device exhibited nearly no sensitivity to visible illumination with wavelength of 405 nm but exhibited pronounced sensitivity to both DUV and UV light illumination with response speeds of 26.2/49.9 ms for rise/fall time. The Ilight/Idark ratio could reach 127. What is more, the responsivity and specific detectivity were calculated to be 64.9 mA W-1 and 6.9 × 1011 Jones, respectively. In addition, the device could keep its photoresponsivity after storage in air environment for a month. It is also found that the capability of Cs3Cu2I5 crystalline film device can readily record still DUV image with acceptable resolution. The above results confirm that the DUV photodetector may hold great potential for future DUV optoelectronic device and systems.

Analysis of HCV resistance mutations during combination therapy with protease inhibitor boceprevir and PEG-IFN alpha-2b using TaqMan mismatch amplification mutation assay.

TaqMan Mismatch Amplification Mutation Assay (TaqMAMA) is a highly sensitive allelic discrimination method. The mismatch amplification mutation assay (MAMA) is based on preferential amplification of mutant allele by the 'MAMA' primer, which is designed to have two mismatches with the wild-type allele and only one mismatch with the mutant allele. In this report, the TaqMAMA method was adapted for the detection and quantitation of minor HCV variants resistant to the protease inhibitor boceprevir (SCH 503034) from clinical samples. A good correlation of mutant frequency was observed between TaqMAMA and the results of clonal sequencing. TaqMAMA detected consistently minor variants at a level as low as 0.1%. Using TaqMAMA, it was demonstrated that resistant variants existed in the viral population before boceprevir treatment. The frequency of two resistant mutants (T54A and V170A) increased significantly during treatment with boceprevir, but was suppressed by combination treatment of PEG-IFN alpha-2b and boceprevir. The prevalence of both mutants decreased at the end of the two-week follow-up period. These results show that TaqMAMA can be used to detect minor resistant variants in pretreatment samples and to study in detail the evolution of mutant viruses during targeted antiviral therapy.

Injectable hydrogels based on glycyrrhizin, alginate, and calcium for three-dimensional cell culture in liver tissue engineering.

Injectable hydrogels have been paid more attentions on cell therapy and tissue regeneration resulting from the applications in minimally invasive surgical procedures with ease of handling and complete filling of defect area. Here, a biodegradable and injectable in situ hydrogel formed by glycyrrhizin (GL), alginate (Alg), and calcium (Ca) was developed for three-dimensional (3D) cell culture. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscope (SEM) and rheology analysis were performed to characterize GL-Alg-Ca hydrogel and evaluate its formation mechanism, properties, and morphology. The biocompatibility of hydrogel was investigated by cell viability, morphology, and liver specific functions. The results of DSC, XRD, and rheology suggested that hydrogel was homogenous complex with stable structure and well viscoelasticity. Human hepatoma HepG2 cells cultured in hydrogels showed well morphology. Compared with the control group, cells in hydrogels showed good biocompatibility, and could maintain the viability, proliferation and liver function for longer periods of time. Furthermore, the hydrogel improved the mRNA expression of cytochrome P450, which were key enzyme to the metabolization of hepatocytes. The GL-Alg-Ca hydrogel could be a potential 3D cells culture system for liver tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3292-3302, 2018.

Improved Tumor Uptake by Optimizing Liposome Based RES Blockade Strategy.

Minimizing the sequestration of nanomaterials (NMs) by the reticuloendothelial system (RES) can enhance the circulation time of NMs, and thus increase their tumor-specific accumulation. Liposomes are generally regarded as safe (GRAS) agents that can block the RES reversibly and temporarily. With the help of positron emission tomography (PET), we monitored the in vivo tissue distribution of 64Cu-labeled 40 × 10 nm gold nanorods (Au NRs) after pretreatment with liposomes. We systematically studied the effectiveness of liposome administration by comparing (1) differently charged liposomes; (2) different liposome doses; and (3) varying time intervals between liposome dose and NR dose. By pre-injecting 400 µmol/kg positively charged liposomes into mice 5 h before the Au NRs, the liver and spleen uptakes of Au NRs decreased by 30% and 53%, respectively. Significantly, U87MG tumor uptake of Au NRs increased from 11.5 ± 1.1 %ID/g to 16.1 ± 1.3 %ID/g at 27 h post-injection. Quantitative PET imaging is a valuable tool to understand the fate of NMs in vivo and cationic liposomal pretreatment is a viable approach to reduce RES clearance, prolong circulation, and improve tumor uptake.

Efficacy and safety of solifenacin succinate tablets versus solifenacin succinate tablets with local estrogen for the treatment of overactive bladder in postmenopausal women--a multicenter, randomized, open-label, controlled comparison study.

OBJECTIVE: The aim of the study was to compare the effectiveness and safety of solifenacin succinate tablets alone or combined with local estrogen for overactive bladder treatment in postmenopausal women. METHODS: This multicenter, randomized, open, parallel-controlled clinical trial enrolled 104 women between January 2012 and August 2013. Participants meeting the inclusion criteria were randomized 1:1 to 12 weeks of treatment with group A (solifenacin 5 mg qd + promestriene vaginal capsules intravaginally) or group B (solifenacin 5 mg qd). Before and after 12 weeks of treatment, symptoms (urinary urgency, frequency, and urge incontinence) were analyzed. Our primary outcome was the change from baseline to the end of treatment in the mean number of voids in 24 hours. Quality of life (QoL) was assessed using International Prostate Symptom Score and Overactive Bladder Symptom Score questionnaires and safety according to the incidence of adverse events. The t test or the Mann-Whitney U test was used to compare continuous variables, and the χ(2) test or Fisher's exact test was used to compare categorical variables. RESULTS: The median decreases in the mean number of voids in 24 hours in groups A and B were 5.2. and 4.3, respectively, which were not significantly different. The median decreases in urgency episodes in groups A and B were 2.0 and 2.5, respectively. In addition, the QoL scores significantly changed in both groups (both P < 0.05). The most common adverse event was dry mouth (19.2% in both groups). CONCLUSIONS: Solifenacin with or without local estrogen was effective and safe for overactive bladder treatment in postmenopausal women. The addition of local estrogen improved subjective feelings and QoL.

Polymeric Nanovehicle Regulated Spatiotemporal Real-Time Imaging of the Differentiation Dynamics of Transplanted Neural Stem Cells after Traumatic Brain Injury.

Recent advances in neural stem cell (NSC) transplantation have led to an inspiring progress in alleviating central nervous system (CNS) damages and restoring brain functions from diseases or injuries. One challenge of NSC transplantation is directed differentiation of transplanted NSCs into desired neuronal subtypes, such as neurons, to compensate the adverse impact of brain injury; another challenge lies in the lack of tools to noninvasively monitor the dynamics of NSC differentiation after transplantation in vivo. In this study, we developed a polymer nanovehicle for morphogen sustained release to overcome the drawbacks of conventional methods to realize the long-term directed NSC differentiation in vivo. Moreover, we constructed a bicistronic vector with a unique neuron specific gene tubb3 promoter to drive reporter gene expression for real-time imaging of NSC differentiation and migration. The developed uniform nanovehicle showed efficient NSC uptake and achieved a controlled release of morphogen in cytosol to consistently stimulate NSC differentiation into neurons at a sustainably effective concentration. The spatiotemporal imaging results showed a multiplexed migration, proliferation, differentiation, and apoptosis orchestra of transplanted NSCs regulated by nanovehicles in TBI mice. The imaging results also uncovered the peak time of NSC differentiation in vivo. Although we observed only a handful of NSCs ultimately migrated to the TBI area and differentiated into neurons, those neurons were functional, ameliorating the detrimental impact of TBI. The imaging findings enabled by the nanovehicle and the neuron specific bicistronic vector provide additional understanding of the in vivo behaviors of transplanted NSCs in neuronal regenerative medicine.

Nd-Fe-B alloy-densified agarose gel for expanded bed adsorption of proteins.

Novel dense composite adsorbents for expanded bed adsorption of protein have been fabricated by coating 4% agarose gel onto Nd-Fe-B alloy powder by a water-in-oil emulsification method. Two composite matrices, namely Nd-Fe-B alloy-densified agarose (NFBA) gels with different size distributions and densities, NFBA-S (50-165 microm, 1.88 g/ml) and NFBA-L (140-300 microm, 2.04 g/ml), were produced. Lysozyme was used as a model protein to test the adsorption capacity and kinetics for the NFBA gels modified by Cibacron blue 3GA (CB-NFBA gels). Liquid-phase dispersion behavior in the expanded beds was examined by measurements of residence time distributions, and compared with that of Streamline SP (Amersham-Pharmacia Biotech, Sweden). The dependence of axial mixing in the expanded beds on flow velocity, bed expansion degree. settled bed height, and viscosity of liquid phase was investigated. Breakthrough curves of lysozyme in the expanded beds of the CB-NFBA gels were also examined. The dynamic binding capacity at 5% breakthrough was 23.3 mg/ml matrix for the CB-NFBA-S gels, and 16.7 mg/ml matrix for the CB-NFBA-L, at a flow velocity of 220 cm/h. The results indicate that the NFBA gels are promising for expanded bed adsorption of proteins.

Correlation between PAMPA permeability and cellular activities of hepatitis C virus protease inhibitors.

Parallel artificial membrane permeability assay (PAMPA) and Caco-2 cells have been frequently used for the evaluation of in vitro permeability of new chemical entities. In this study we evaluated the correlation between permeability, assessed by both methods, and the cellular potency of 34 novel hepatitis C virus (HCV) protease inhibitors. Two types of assays were used to determine the potency of HCV protease inhibitors: a cell-free assay that evaluates the intrinsic affinity (K(i)) between the protease and the inhibitor and a cell-based replicon assay that determines the inhibitors' IC90. When the K(i)/IC90 ratios were compared with the PAMPA permeability and the Caco-2 permeability by linear regression analysis, a reasonable correlation was found between the K(i)/IC90 ratio and PAMPA permeability (r2=0.76) but not with Caco-2 permeability (r2=0.29). Correlations were also assessed between K(i)/IC90 ratios and the following physico-chemical properties: logP (r2=0.41), logD (r2=0.58), clogP (r2=0.13), and mlogP (r2=0.30). These results suggest that passive permeability may play a role in the uptake and cellular activity of these HCV protease inhibitors, and that PAMPA was more predictive of cellular activity than physico-chemical properties or Caco-2 permeability.