Flavivirus genome recoding by codon optimisation confers genetically stable in vivo attenuation in both mice and mosquitoes.

Virus genome recoding is an attenuation method that confers genetically stable attenuation by rewriting a virus genome with numerous silent mutations. Prior flavivirus genome recoding attempts utilised codon deoptimisation approaches. However, these codon deoptimisation approaches act in a species dependent manner and were unable to confer flavivirus attenuation in mosquito cells or in mosquito animal models. To overcome these limitations, we performed flavivirus genome recoding using the contrary approach of codon optimisation. The genomes of flaviviruses such as dengue virus type 2 (DENV2) and Zika virus (ZIKV) contain functional RNA elements that regulate viral replication. We hypothesised that flavivirus genome recoding by codon optimisation would introduce silent mutations that disrupt these RNA elements, leading to decreased replication efficiency and attenuation. We chose DENV2 and ZIKV as representative flaviviruses and recoded them by codon optimising their genomes for human expression. Our study confirms that this recoding approach of codon optimisation does translate into reduced replication efficiency in mammalian, human, and mosquito cells as well as in vivo attenuation in both mice and mosquitoes. In silico modelling and RNA SHAPE analysis confirmed that DENV2 recoding resulted in the extensive disruption of genomic structural elements. Serial passaging of recoded DENV2 resulted in the emergence of rescue or adaptation mutations, but no reversion mutations. These rescue mutations were unable to rescue the delayed replication kinetics and in vivo attenuation of recoded DENV2, demonstrating that recoding confers genetically stable attenuation. Therefore, our recoding approach is a reliable attenuation method with potential applications for developing flavivirus vaccines.

Attenuation of neurovirulence of chikungunya virus by a single amino acid mutation in viral E2 envelope protein.

BACKGROUND: Chikungunya virus (CHIKV) has reemerged as a major public health concern, causing chikungunya fever with increasing cases and neurological complications. METHODS: In the present study, we investigated a low-passage human isolate of the East/ Central/South African (ECSA) lineage of CHIKV strain LK(EH)CH6708, which exhibited a mix of small and large viral plaques. The small and large plaque variants were isolated and designated as CHIKV-SP and CHIKV-BP, respectively. CHIKV-SP and CHIKV-BP were characterized in vitro and in vivo to compare their virus production and virulence. Additionally, whole viral genome analysis and reverse genetics were employed to identify genomic virulence factors. RESULTS: CHIKV-SP demonstrated lower virus production in mammalian cells and attenuated virulence in a murine model. On the other hand, CHIKV-BP induced higher pro-inflammatory cytokine levels, compromised the integrity of the blood-brain barrier, and led to astrocyte infection in mouse brains. Furthermore, the CHIKV-SP variant had limited transmission potential in Aedes albopictus mosquitoes, likely due to restricted dissemination. Whole viral genome analysis revealed multiple genetic mutations in the CHIKV-SP variant, including a Glycine (G) to Arginine (R) mutation at position 55 in the viral E2 glycoprotein. Reverse genetics experiments confirmed that the E2-G55R mutation alone was sufficient to reduce virus production in vitro and virulence in mice. CONCLUSIONS: These findings highlight the attenuating effects of the E2-G55R mutation on CHIKV pathogenicity and neurovirulence and emphasize the importance of monitoring this mutation in natural infections.

Physiologically based pharmacokinetic combined BTK occupancy modeling for optimal dosing regimen prediction of acalabrutinib in patients alone, with different CYP3A4 variants, co-administered with CYP3A4 modulators and with hepatic impairment.

PURPOSE: To develop a mathematical model combined between physiologically based pharmacokinetic and BTK occupancy (PBPK-BO) to simultaneously predict pharmacokinetic (PK) and pharmacodynamic (PD) changes of acalabrutinib (ACA) and active metabolite ACP-5862 in healthy humans as well as PD in patients. Next, to use the PBPK-BO to determine the optimal dosing regimens in patients alone, with different CYP3A4 variants, when co-administration with four CYP3A4 modulators and in patients with hepatic impairment, respectively. METHODS: The PBPK-BO model was built using physicochemical and biochemical properties of ACA and ACP-5862 and then verified by observed PK and PD data from healthy humans and patients. Finally, the model was applied to determine optimal dosing regimens in various clinical situations. RESULTS: The simulations demonstrated that 100 mg ACA twice daily (BID) was the optimal dosing regimen in patients alone. Additionally, dosage regimens might be reduced to 50 mg BID in patients with five CYP3A4 variants. Moreover, the dosing regimen should be modified to 100 mg (even to 50 mg) once daily (QD) when co-administration with erythromycin or clarithromycin, and be increased to 200 mg BID with rifampicin, and but be avoided co-administration with itraconazole. Furthermore, dosage regimen simulations showed that optimal dosing might be decreased to 50 mg BID in patients with mild and moderate hepatic impairment, and be avoided taking ACA in severely hepatically impaired patients. CONCLUSION: This PBPK-BO model can predict PK and PD in healthy humans and patients and also predict the optimal dosing regimens in various clinical situations.

Physiologically based pharmacokinetic combined JAK2 occupancy modelling to simulate PK and PD of baricitinib with kidney transporter inhibitors and in patients with hepatic/renal impairment.

PURPOSE: Our aim is to build a physiologically based pharmacokinetic and JAK2 occupancy model (PBPK-JO) to simultaneously predict pharmacokinetic (PK) and pharmacodynamic (PD) changes of baricitinib (BAR) in healthy humans when co-administrated with kidney transporters OAT3 and MATE2-K inhibitors, and in patients with hepatic and renal impairment. METHODS: Probenecid and vandetanib were selected as OAT3 and MATE2-K competitive inhibitors, respectively. The PBPK-JO model was built using physicochemical and biochemical properties of BAR, and then verified by observed clinical PK. Finally, the model was applied to determine optimal dosing regimens in various clinical situations. RESULTS: Here, we have successfully simulated PK and JAK2 occupancy profiles in humans by PBPK-JO model. Moreover, this modelling reproduced every observed PK data, and every mean relative deviation (MRD) was below 2. The simulation suggested that PK of BAR had a significant change (2.22-fold increase), however PD only had a slight increase of 1.14-fold. Additionally, the simulation also suggested that vandetanib was almost unlikely to affect the PK and PD of BAR. In simulations of hepatic and renal impairment patients, the predictions suggested that significant changes in the PK and PD of BAR occurred. However, there was a lower fold increase in JAK2 occupancy than in PK in patients relative to healthy individuals. CONCLUSION: Administration dose adjustment of BAR when co-administrated with OAT3 inhibitors or in patients with hepatic or renal impairment should combine PK and PD changes of BAR, instead of only considering PK alteration.

[Optimization of formulas of Quban gel by uniform design].

OBJECTIVE: To optimize formulas of Quban gel. METHOD: The U6 (6(2) x 3) uniform design was adopted to optimize gel formulas, with rheological parameters, such as viscosity and yield value in room temperature, viscosity and yield value in average temperature of skin, thixlotropy. RESULT: The optimum proportion of matrix was made of 1.0 g carbomer 940, 5 mL glycerin and pH value 5-6. CONCLUSION: The regression model for gel matrix quality and gel rheological parameters was established to directly reflect the impacting effect of various factors, and provide certain preference basis for the screening of gel matrix formulas. Quban gel prepared by the method was evenly distributed, moderately viscous and highly thixotropic

Chelerythrine chloride inhibits Zika virus infection by targeting the viral NS4B protein.

Zika virus (ZIKV) is a mosquito-borne virus that has re-emerged as a significant threat to global health in the recent decade. Whilst infections are primarily asymptomatic, the virus has been associated with the manifestation of severe neurological complications. At present, there is still a lack of approved antivirals for ZIKV infections. In this study, chelerythrine chloride, a benzophenanthridine alkaloid, was identified from a mid-throughput screen conducted on a 502-compound natural products library to be a novel and potent inhibitor of ZIKV infection in both in-vitro and in-vivo assays. Subsequent downstream studies demonstrated that the compound inhibits a post-entry step of the viral replication cycle and is capable of disrupting viral RNA synthesis and protein expression. The successful generation and sequencing of a ZIKV resistant mutant revealed that a single S61T mutation on the viral NS4B allowed ZIKV to overcome chelerythrine chloride inhibition. Further investigation revealed that chelerythrine chloride could directly inhibit ZIKV protein synthesis, and that the NS4B-S61T mutation confers resistance to this inhibition. This study has established chelerythrine chloride as a potential candidate for further development as a therapeutic agent against ZIKV infection.

Antiviral Activity of Catechin against Dengue Virus Infection.

Dengue virus (DENV) is the cause of dengue fever, infecting 390 million people worldwide per year. It is transmitted to humans through the bites of mosquitoes and could potentially develop severe symptoms. In spite of the rising social and economic impact inflicted by the disease on the global population, a conspicuous lack of efficacious therapeutics against DENV still persists. In this study, catechin, a natural polyphenol compound, was evaluated as a DENV infection inhibitor in vitro. Through time-course studies, catechin was shown to inhibit a post-entry stage of the DENV replication cycle. Further investigation revealed its role in affecting viral protein translation. Catechin inhibited the replication of all four DENV serotypes and chikungunya virus (CHIKV). Together, these results demonstrate the ability of catechin to inhibit DENV replication, hinting at its potential to be used as a starting scaffold for further development of antivirals against DENV infection.

Economics of planning electricity transmission considering environmental and health externalities.

Long-distance electricity transmission can achieve environmental benefits through the transfer of air pollutants. However, current electricity transmission investment decisions do not take enough environmental factors into account. This study combines Greenhouse Gas-Air Pollution Interactions and Synergies model with power system planning to reveal how regional differences in environmental and health losses affect the allocation of electricity at the spatial level. Based on the analysis of inter-provincial electricity interconnection in China, we find that the regional differences in environmental and health external costs of power generation are significant. Considering external costs in investment decisions will largely improve the economy of long-distance inter-regional electricity transfer dominated by ultra-high voltage lines, thus replacing a portion of intra-regional electricity transfer dominated by high voltage lines. Meanwhile, the increases in local health losses in major electricity exporting provinces are not significant, which can alleviate the regional equity issues caused by pollutant transfer.

[Percutaneous permeability study for patches Shangshi Zhitong on different kinds of bases].

OBJECTIVE: To study the percutaneous permeability of patches Shangshi Zhitong on different kinds of bases with the permeation percentage of brucine, strychnine and atropine. METHOD: Using modified Franz difusion to investigate the penetration quantity of brucine, strychnine and atropine. The contents of brucine, strychnine and atropine were determined by HPLC. RESULT: The average accumulative permeation percentage of brucine, strychnine and atropine on new base were 53.25%, 74.52% were 34.32%, respectively, and on old base are 54.90%, 50.24%, 46. 54%, respectively. CONCLUSION: The new base benefits the lipophilic drugs and releases more stably.

Effect of CYP3A4 Inhibitors and Inducers on Pharmacokinetics and Pharmacodynamics of Saxagliptin and Active Metabolite M2 in Humans Using Physiological-Based Pharmacokinetic Combined DPP-4 Occupancy.

We aimed to develop a physiological-based pharmacokinetic and dipepidyl peptidase 4 (DPP-4) occupancy model (PBPK-DO) characterized by two simultaneous simulations to predict pharmacokinetic (PK) and pharmacodynamic changes of saxagliptin and metabolite M2 in humans when coadministered with CYP3A4 inhibitors or inducers. Ketoconazole, delavirdine, and rifampicin were selected as a CYP3A4 competitive inhibitor, a time-dependent inhibitor, and an inducer, respectively. Here, we have successfully simulated PK profiles and DPP-4 occupancy profiles of saxagliptin in humans using the PBPK-DO model. Additionally, under the circumstance of actually measured values, predicted results were good and in line with observations, and all fold errors were below 2. The prediction results demonstrated that the oral dose of saxagliptin should be reduced to 2.5 mg when coadministrated with ketoconazole. The predictions also showed that although PK profiles of saxagliptin showed significant changes with delavirdine (AUC 1.5-fold increase) or rifampicin (AUC: a decrease to 0.19-fold) compared to those without inhibitors or inducers, occupancies of DPP-4 by saxagliptin were nearly unchanged, that is, the administration dose of saxagliptin need not adjust when there is coadministration with delavirdine or rifampicin.

Estimating air pollution and health loss embodied in electricity transfers: An inter-provincial analysis in China.

Electricity generation may create high levels of pollution, but its consumption is completely clean. Long-distance electricity transfers make the allocation of environmental externalities caused by electricity generation unfair at the regional level. This paper provides a generalized approach that can be used to evaluate air pollution and health loss embodied in electricity transfers. Impact pathway approach is combined with a network approach to evaluate embodied direct health loss and a sophisticated evaluation of air pollution diffusion is implemented to assess indirect environmental impacts between regions. Using China's inter-provincial power transmission as an example, this paper also reveals various air pollutant and health loss transfer patterns among the nation's provinces. The results emphasize the importance of characterizing the embodied environmental effects in electricity transfer through health losses rather than air pollution emissions. The inter-regional indirect impacts due to the diffusion of pollutants must be considered when examining the embodied health losses, which is even higher than the direct impact on the local. Several central regions in China, adjacent to the major electricity-export provinces, do not export a large amount of electricity, yet their health losses have increased significantly due to nationwide power transfers. The direct external health costs of electricity generation in China's major power-exporting provinces are relatively low. However, when indirect impacts are considered, external costs in the central and northern regions increase significantly. Therefore, the regional environmental benefits of shifting electricity generation to resource-rich remote areas are greatly reduced for many pairs of provinces.

[Application of thermoplastic elastomer in hot-melt pressure sensitive adhesives for transtermal drug delivery].

Development of drug dosage forms to a great extent depends on the development of drug auxiliary materials. The development of a new type of polymeric drug auxiliary materials will bring on the developing of a novel dosage forms technology and a flood of new drug dosage forms. Thermoplastic elastomer is a new type of drug polymeric auxiliary materials, at present, which has a broad application in the field of hot-melt pressure sensitive adhesives. This review mainly discussed a new transtermal Chinese drug delivery system, including matrix composition of the formula, modified thermoplastic elastomer for hot-melt pressure sensitive adhesives and their development prospects in the traditional Chinese drug delivery system. It suggested that thermoplastic elastomer of hot-melt pressure sensitive adhesives has broad development prospects in the field of the transtermal drug delivery system for traditional Chinese medicine.

Relation of Blood Arsenic Concentration with Effect and Safety of Arsenic-Containing Qinghuang Powder () in Patients with Myelodysplastic Syndrome.

OBJECTIVE: To investigate the relation of blood arsenic concentration (BAC) with clinical effect and safety of arsenic-containing Qinghuang Powder (, QHP) in patients with myelodysplastic syndrome (MDS). METHODS: Totally 163 patients with MDS were orally treated with QHP for 2 courses of treatment, 3 months as 1 course. The BACs of patients were detected by atomic fluorescence spectrophotometry at 1, 3, and 6 months during the treatment, and the effective rate, hematological improvement and safety in patients after treatment with QHP were analyzed. RESULTS: After 2 courses of treatment, the total effective rate was 89.6% (146/163), with 31.3% (51/163) of hematological improvement and 58.3% (95/163) of stable disease. The hemoglobin increased from 73.48 ± 19.30 g/L to 80.39 ± 26.56 g/L (P<0.05), the absolute neutrophil count increased from 0.81 ± 0.48 × 109/L to 1.08 ± 0.62 × 109/L (P<0.05), and no significant changes were observed in platelet counts (P>0.05). Among 46 patients previously depended on blood transfusion, 28.3% (13/46) completely got rid of blood transfusion and 21.7% (10/46) reduced the volume of blood transfusion by more than 50% after treatment. The BACs were significantly increased in patients treated for 1 month with 32.17 ± 18.04 µ g/L (P<0.05), 3 months with 33.56 ± 15.28 µ g/L (P<0.05), and 6 months with 36.78 ± 11.92 µ g/L (P<0.05), respectively, as compared with those before treatment (4.08 ± 2.11 µ g/L). There were no significant differences of BACs among the patients treated for 1, 3 and 6 months (P>0.05). The adverse reactions of digestive tract during the treatment were mild abdominal pain and diarrhea in 14 cases (8.6%), and no patients discontinued the treatment. The BACs of patients with gastrointestinal adverse reactions were significantly lower than those without gastrointestinal adverse reactions (22.39 ± 10.38 vs. 37.89 ± 11.84, µ g/L, P<0.05). The BACs of patients with clinical effect were significantly higher than those failed to treatment (40.41 ± 11.69 vs. 23.84 ± 12.03, µ g/L, P<0.05). CONCLUSION: QHP was effective and safe in the treatment of patients with MDS and the effect was associated with BACs of patients.

Paeoniflorin Promotes Angiogenesis in A Vascular Insufficiency Model of Zebrafish in vivo and in Human Umbilical Vein Endothelial Cells in vitro.

OBJECTIVE: To investigate the pro-angiogenic effects of paeoniflorin (PF) in a vascular insufficiency model of zebrafish and in human umbilical vein endothelial cells (HUVECs). METHODS: In vivo, the pro-angiogenic effects of PF were tested in a vascular insufficiency model in the Tg(fli-1:EGFP)y1 transgenic zebrafish. The 24 h post fertilization (hpf) embryos were pretreated with vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor II (VRI) for 3 h to establish the vascular insufficiency model and then post-treated with PF for 24 h. The formation of intersegmental vessels (ISVs) was observed with a fluorescence microscope. The mRNA expression of fms-like tyrosine kinase-1 (flt-1), kinase insert domain receptor (kdr), kinase insert domain receptor like (kdrl) and von Willebrand factor (vWF) were analyzed by real-time polymerase chain reaction (PCR). In vitro, the pro-angiogenic effects of PF were observed in HUVECs in which cell proliferation, migration and tube formation were assessed. RESULTS: PF (6.25-100 µmol/L) could rescue VRI-induced blood vessel loss in zebrafish and PF (25-100 µmol/L), thereby restoring the mRNA expressions of flt-1, kdr, kdrl and vWF, which were down-regulated by VRI treatment. In addition, PF (0.001-0.03 µmol/L) could promote the proliferation of HUVECs while PF stimulated HUVECs migration at 1.0-10 µmol/L and tube formation at 0.3 µmol/L. CONCLUSION: PF could promote angiogenesis in a vascular insufficiency model of zebrafish in vivo and in HUVECs in vitro.

Optimization and Standardization of the Immunodeficient Mouse Model for Assessing Fat Grafting Outcomes.

BACKGROUND: Animal models are often used to assess interventions that might improve fat grafting outcomes; however, there is great variability in the models. The authors sought to determine the predictive value of the immunocompromised mouse model for fat grafting so that experiments could be standardized and optimized. METHODS: Human lipoaspirate injections at different volumes and time points were assessed in a nude mouse model and compared with control injections of nonviable fat. Volume retention and explant histologic score were compared. In a separate study, interanimal reproducibility was determined by implanting a highly consistent hydrogel and measuring variability in volume retention. RESULTS: Injection volume significantly affects adipose resorption kinetics at 6 and 12 weeks. Masson trichrome staining revealed that macrophages were unable to infiltrate large (1 ml) grafts, and oil cysts were not absorbed by 18 weeks, which interfered with interpretation of volume retention data. Nonviable tissue was resorbed when grafts were 0.3 ml, and quantification of graft histologic viability correlated well with graft retention at all study time points. Interanimal variability was measured to be 8.44 percent of the mean retention volume for small graft volumes. CONCLUSIONS: Human fat graft retention in the immunodeficient mouse correlates with graft viability in small, 0.3-ml-volume grafts. However, centralized oil cysts in nonviable 1.0-ml grafts were not resorbed by 18 weeks and thus volume measurements were confounded and not significantly different from viable samples. In addition, tissue injury scores increased in initially healthy fat grafts at 18 weeks, possibly because of a delayed immune reaction.

A nonlinear updated gain observer for MIMO systems: Design, analysis and application to marine surface vessels.

In this paper, the state estimation problem of a class of multi-input-multi-output nonlinear systems with measurement noise is studied. We develop an extended updated-gain high gain observer to make a tradeoff between reconstruction speed and measurement noise attenuation. The designed observer, whose gains are driven by nonlinear functions of the available output estimation errors, has the ability to reconstruct system states quickly and reduce the effect of measurement noise. We establish that, if there exists a state feedback law exponentially stabilizing the system with respect to an invariant set, the estimations and estimation errors are bounded. Besides, the trajectories of state- and output-feedback (based on the proposed observer) are sufficiently close, namely performance recovery. The observer performance is illustrated by various examples in marine control, including a case of transformation into the predefined structure.