Population pharmacokinetic modeling of levodropropizine: extended application to comparative analysis between commercial formulations and exploration of pharmacokinetic effects of diet

Levodropropizine, a nonopioid antitussive agent, is being increasingly used in clinical practice with the development of several formulations for symptomatic relief of acute and chronic bronchitis. However, scientific and quantitative population pharmacokinetic analyses of levodropropizine are lacking. Moreover, no integrated quantitative comparison has been performed between formulations. This study quantitatively evaluated and predicted pharmacokinetic properties of formulations through population pharmacokinetic model-based comparisons of commercially available formulations. Plasma concentration profile results from bioequivalence studies of 60-mg immediate release (IR) levodropropizine tablets in 40 healthy Korean males were used as population pharmacokinetic modeling data. For interindividual variability in levodropropizine pharmacokinetics, body surface area was identified as an effective covariate that was positively correlated with peripheral compartment distribution volume. Population pharmacokinetic model for IR tablets well-described the levodropropizine syrup and capsule datasets, suggesting no significant differences in pharmacokinetics among IR tablets, syrups, and capsules of levodropropizine. In contrast, pharmacokinetic profiles differed between 90-mg controlled release (CR) and IR levodropropizine tablets; however, separate parameter estimation was possible by applying the same model structure. In terms of pharmacokinetics, twice-daily regimen of 90-mg CR tablets was equivalent to thrice-daily regimen of 60-mg IR tablets. However, at steady-state, interindividual plasma concentration variability within population was reduced by approximately 36.71-83.18%. For levodropropizine CR tablets, a high-fat diet significantly delayed gastrointestinal absorption but maintained overall plasma exposure equivalent. This study provides useful quantitative judgment data for precision medicine of levodropropizine and can be helpful in predicting the pharmacokinetics of levodropropizine based on commercialized formulation switching.

Green and inventive fluorescence approach for levodropropizine determination in human plasma

A green, rapid and sensitive fluorimetric method to quantify levodropropizine (LVP) in human plasma was exploited for the first time. The proposed method adopts LVP's intrinsic fluorescence in distilled water at a detecting emission of 345 nm following excitation at 240 nm. LVP displayed linearity across concentrations ranging from 50 to 1000 ng mL-1, with a detection limit of 0.77 ng mL-1 and a quantification limit of 2.33 ng mL-1. Thorough validation confirmed its reliability, successfully determining LVP in tablets with an average recovery of 98.64 ± 1.07 %. Furthermore, the method's applicability extended to estimate the studied drug in spiked human plasma with excellent obtained percentage recoveries (98.68 ± 1.28-100.14 ± 1.23).

Enhanced Solubility and Bioavailability of Clotrimazole in Aqueous Solutions with Hydrophobized Hyperbranched Polyglycidol for Improved Antifungal Activity

The poor solubility of clotrimazole in the aqueous medium and the uncontrolled removal of the drug-loaded suppository content limit its effectiveness in the treatment of vulvovaginal candidiasis. We present here the aqueous formulations of clotrimazole in the form of non-Newtonian structured fluids, i.e., Bingham plastic or pseudoplastic fluids constructed of hyperbranched polyglycidol, HbPGL, with a hydrophobized core with aryl groups such as phenyl or biphenyl. The amphiphilic constructs were obtained by the modification of linear units containing monohydroxyl groups with benzoyl chloride, phenyl isocyanate, and biphenyl isocyanate, while the terminal 1,2-diol groups in the shell were protected during the modification step, followed by their deprotection. The encapsulation of clotrimazole within internally hydrophobized HbPGLs using a solvent evaporation method followed by water addition resulted in structured fluids formation. Detailed Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses performed for aryl-HbPGLs with clotrimazole revealed the difference in drug compatibility among polymers. Clotrimazole in biphenyl-enriched HbPGL, unlike phenyl derivatives, was molecularly distributed in both the dry and the hydrated states, resulting in transparent formulations. The shear-thinning properties of the obtained fluid formulations make them injectable and thus suitable for the intravaginal application. Permeability tests performed with the usage of the Franz diffusion cell showed a 5-fold increase in the permeability constant of clotrimazole compared to drugs loaded in a commercially available disposable tablet and a 50-fold increase of permeability in comparison to the aqueous suspension of clotrimazole. Furthermore, the biphenyl-modified HbPGL-based drug liquid showed enhanced antifungal activity against both Candida albicans and Candida glabrata that was retained for up to 7 days, in contrast to the phenyl-HbPGL derivatives and the tablet. With their simple formulation, convenient clotrimazole/biphenyl-HbPGL formulation strategy, rheological properties, and enhanced antifungal properties, these systems are potential antifungal therapeutics for gynecological applications. This study points in the synthetic direction of improving the solubility of poorly water-soluble aryl-enriched pharmaceuticals.

Celecoxib-hydroxypropyl-β-cyclodextrin inclusion complex in a chitosan/PEO-PPO-PEO block copolymer matrix: Structural effect and drug release

HYPOTHESIS

Triblock copolymers of poly(ethylene oxide) and poly(propylene oxide)-based matrices, such as Poloxamer 407 (P407) or Pluronic® F127, are extensively utilized in drug delivery and permeation systems due to their FDA approval and listing in the US and European Pharmacopoeias. The study hypothesizes that incorporating 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and the celecoxib-HP-β-CD inclusion complex into a 16 wt% P407 and chitosan blend in an aqueous acetic acid solution will affect the system's rheological and structural properties.

EXPERIMENTS

Rheological, small-angle X-ray scattering (SAXS), and dynamic light scattering (DLS) experiments were conducted to assess the impact of acetic acid and chitosan on the 16 wt% P407 and chitosan blend. Additionally, in vitro drug release studies were performed to monitor the drug release profile over time.

FINDINGS

The addition of HP-β-CD was found to inhibit gel formation in the 16 wt% P407 and chitosan blend. However, the presence of the celecoxib-HP-β-CD inclusion complex showed no significant structural effects compared to P407 blended with chitosan alone. Rheological and SAXS analyses demonstrated that acetic acid led to the formation of a lamellar phase due to the lower pH, facilitating injectability. The presence of chitosan in acetic acid resulted in the detection of a hexagonal phase, affecting the release of celecoxib.

Occurrence and risk assessment of glycidyl and 3-monochloropropanediol esters in infant formulas marketed in Taiwan

Glycidyl esters (GEs) and 3-monochloropropanediol esters (3-MCPDEs) are process contaminants commonly found in refined edible oils which are often added to infant formulas. The Taiwan Food and Drug Administration (TFDA) launched regulations for GEs in infant formulas that went into effect on 1 July 2021. To investigate levels of GEs and 3-MCPDEs in infant formula powder, 45 products were sampled and analysed during 2020-2021. The contents of GEs and 3-MCPDEs in formulas of different brands significantly varied, but their concentrations in all of the formulas complied with European Union (EU) regulations. Infant formulas containing palm oil had significantly higher 3-MCPDE levels in both extracted oils and milk powder than those without palm oil. Concentrations of GEs and 3-MCPDEs in infant formula powder and extracted oils were significantly lower in products from Europe than those from Australia and New Zealand. Infants aged 0-1 years in Taiwan who consumed only infant formula showed a margin of exposure (MoE) exceeding 25,000. Mean consumer exposures to 3-MCPDEs stayed below the tolerable daily intake (TDI), while high exposures at the 95th percentile (P95) exceeded the TDI by 1.7-fold. Herein, we present the changing trends in the risk assessment results of infant formula across various countries in the decade. Implementation of regulations and mitigation strategy effectively reduced the risk of infants being exposed to GEs and 3-MCPDEs through infant formula.

Eco-friendly novel deconvoluted synchronous spectrofluorimetric approach for the determination of favipiravir, levodropropizine and moxifloxacin hydrochloride as an effective therapeutic combination for COVID-19; application in laboratory prepared mixtures and spiked human plasma

In this work, a green, fast, and simple synchronous spectrofluorimetric approach has been developed to simultaneously determine favipiravir, levodropropizine, and moxifloxacin hydrochloride as co-administered medications for COVID-19 treatment in pure form and spiked human plasma. The synchronous fluorescence spectroscopy technique to analyze the studied drugs at Δλ = 110 nm enabled the determination of levodropropizine at 360 nm. Then, applying Fourier Self-Deconvolution to each spectra to measure favipiravir and moxifloxacin hydrochloride at peak amplitudes of 431 nm and 479 nm, respectively, without any interference. Favipiravir, levodropropizine, and moxifloxacin hydrochloride could be sensitively determined using the described approach over concentration ranges of 20-300 ng/mL, 10-600 ng/mL, and 50-500 ng/mL, respectively. The method's validation was carried out effectively in accordance with guidelines recommended by the ICH. Finally, the Eco-scale and Green Analytical Procedure Index (GAPI) techniques have been used to evaluate the greenness of the proposed method.

Glycols: The ubiquitous solvent for dermal formulations

Glycols stand out as one of the most commonly employed safe and effective excipients for pharmaceutical and cosmeceutical products. Their widespread adoption can be attributed to their exceptional solvency characteristics and their ability to interact effectively with skin lipids and keratin for permeation enhancement. Notably, propylene glycol enjoys significant popularity in this regard. Ongoing research endeavours have been dedicated to scrutinising the impact of glycols on dermal drug delivery and shedding light on the intricate mechanisms by which glycols enhance skin permeation. This review aims to mitigate the discordance within the existing literature, assemble a holistic understanding of the impact of glycols on the percutaneous absorption of active compounds and furnish the reader with a profound comprehension of the foundational facets pertaining to their skin permeation enhancement mechanisms, while simultaneously delving deeper into the intricacies of these processes.

Acute toxicology on Danio rerio embryo and adult from Chinese traditional medicine preparation Danggui Shaoyao san

ETHNOPHARMACOLOGICAL RELEVANCE

Although the Traditional Chinese Medicine (TCM) prescription of Danggui Shaoyao San (DSS) presents substantial clinical efficacy and promising clinical prospects, the safety of DSS and its extracts have been inadequately investigated. The larva-adult duality of the zebrafish model offers a more efficient approach for evaluating the safety of herbal preparations in the fields of toxicology and pharmacology.

AIM OF THE STUDY

To investigate the acute toxicity of the extract derived from Danggui Shaoyao San, a traditional Chinese medicine preparation, on both Danio rerio embryos and adult organisms.

MATERIALS AND METHODS

The components of DSS were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The hatching rate of Danio rerio juveniles with different concentrations of DSS was calculated and the morphological changes of juveniles after administration were observed through a microscope. The behavioral trajectory of the adult fish was recorded by the observation tower of the automated Danio rerio analysis system, and DSS's effects on the behavior was analyzed. The pathological changes of Danio rerio gills, livers, kidneys, intestines and spermaries were examined using HE staining.

RESULTS

Compared with the control group, 25, 50 and 100 mg/L of DSS did not elicit any significant impacts on the hatching rate and morphology. Both 200 mg/L and the propylene glycol 2% reduced the hatching rate and caused the morphological teratogenic changes of the juvenile fish. The dosage of DSS below 100 mg/L had no discernible effect on the behavior of the adult fish, whereas the application of propylene glycol 2% was found to stimulate the adult fish, resulting in a notable increase in high-speed movement distance. 100 mg/L DSS group was not observed to cause any noticeable damage to the gills, livers, intestines and spermaries of Danio rerio, only mild nephrotoxicity was detected. The propylene glycol 2% group was found to result in pathological changes such as hyperplasia of epithelial cells on secondary lamellae, liver cell outline loss or atypia, tubal disorganization, goblet cell hypertrophy and irregularly arranged spermatozoa.

CONCLUSION

A viable approach for conducting toxicological studies on TCM preparations was developed and tested in this research. The findings showed that Danggui Shaoyao San has minimal acute toxicity to embryos and adult organisms at concentrations up to 100 mg/L. These results indicate that Danggui Shaoyao San is a safe TCM preparation.

Preparation and thermostability of a Si/P/N synergistic flame retardant containing triazine ring structure for cotton fabrics

A new synergistic flame retardant named Bisiminopropyl trimethoxysilane-1,3,5-triazine-O-bicyclic pentaerythritol phosphate (BTPODE) was synthesized, which is a type of Si/P/N flame retardant. This was accomplished by grafting aminopropyl trimethoxysilane and bicyclic pentaerythritol phosphate onto a triazine ring structure, serving as an intermediate. The structure of BTPODE was determined using nuclear magnetic resonance (1H NMR, 13C NMR, and 31P NMR) and Fourier transform infrared spectroscopy (FT-IR). SEM was used to detect the surface morphology of cotton fabrics, which suggested that BTPODE had been resoundingly stick to cotton fabrics. The flame retardant properties of cotton fabrics were evaluated by measuring the limiting oxygen index (LOI) and conducting vertical flammability experiments. Cotton fabrics with a weight gain of 20.73 % achieved an LOI value of 32.5 %. Thermogravimetric (TG) experiments demonstrated the samples' good thermostability. Furthermore, under nitrogen conditions, the char residue of cotton fabric with a weight gain of 20.73 % was 36.85 %. The cone calorimetry test (CONE) showed a significant reduction in the TSP value, indicating a certain level of smoke suppression performance. Finally, based on the obtained experimental results, the fire-retardant mechanism principle of the flame retardant was deduced.

Effect of fasedienol (PH94B) pherine nasal spray and steroidal hormones on electrogram responses and autonomic nervous system activity in healthy adult volunteers

OBJECTIVE

Fasedienol (PH94B) is a pherine compound formulated as a nasal spray that is hypothesized to regulate olfactory-amygdala circuits of fear and anxiety. Fasedienol's effect on the local electrogram of nasal chemosensory neurons (EGNR) and autonomic nervous system (ANS) responses versus steroidal hormones and controls in healthy adults is reported.

METHODS

Eight males and 8 females randomly received aerosolized control (propylene glycol) and study drugs (fasedienol, 17β-estradiol, progesterone, cortisol, and testosterone, 0.4 μg each in propylene glycol) onto the nasal septum mucosal lining at 30-min intervals over 2 sessions. EGNR was continuously monitored; autonomic parameters were recorded before and after administration.

RESULTS

Fasedienol significantly increased EGNR amplitude (males: 5.0 vs. 0.6 mV, p < 0.001; females:5.7 vs. 0.6 mV, p < 0.001), and rapidly reduced respiratory rate (p < 0.05), heart rate (p < 0.01), and electrodermal activity (p < 0.05) versus control. EGNR and ANS responses after steroidal hormone administration were similar to control. 81% reported feeling less tense/more relaxed after receiving fasedienol, but not after receiving either control or steroidal hormones.

CONCLUSIONS

Intranasal fasedienol, but not control or steroidal hormones, activated EGNR and rapidly reduced ANS responses, consistent with sympatholytic effects. Combined with subjective reports, results suggest fasedienol may provide acute relief in anxiety conditions.

A genome-reduced Corynebacterium glutamicum derivative discloses a hidden pathway relevant for 1,2-propanediol production

BACKGROUND

1,2-propanediol (1,2-PDO) is widely used in the cosmetic, food, and drug industries with a worldwide consumption of over 1.5 million metric tons per year. Although efforts have been made to engineer microbial hosts such as Corynebacterium glutamicum to produce 1,2-PDO from renewable resources, the performance of such strains is still improvable to be competitive with existing petrochemical production routes.

RESULTS

In this study, we enabled 1,2-PDO production in the genome-reduced strain C. glutamicum PC2 by introducing previously described modifications. The resulting strain showed reduced product formation but secreted 50 ± 1 mM D-lactate as byproduct. C. glutamicum PC2 lacks the D-lactate dehydrogenase which pointed to a yet unknown pathway relevant for 1,2-PDO production. Further analysis indicated that in C. glutamicum methylglyoxal, the precursor for 1,2-PDO synthesis, is detoxified with the antioxidant native mycothiol (MSH) by a glyoxalase-like system to lactoylmycothiol and converted to D-lactate which is rerouted into the central carbon metabolism at the level of pyruvate. Metabolomics of cell extracts of the empty vector-carrying wildtype, a 1,2-PDO producer and its derivative with inactive D-lactate dehydrogenase identified major mass peaks characteristic for lactoylmycothiol and its precursors MSH and glucosaminyl-myo-inositol, whereas the respective mass peaks were absent in a production strain with inactivated MSH synthesis. Deletion of mshA, encoding MSH synthase, in the 1,2-PDO producing strain C. glutamicum ΔhdpAΔldh(pEKEx3-mgsA-yqhD-gldA) improved the product yield by 56% to 0.53 ± 0.01 mM1,2-PDO mMglucose-1 which is the highest value for C. glutamicum reported so far.

CONCLUSIONS

Genome reduced-strains are a useful basis to unravel metabolic constraints for strain engineering and disclosed in this study the pathway to detoxify methylglyoxal which represents a precursor for 1,2-PDO production. Subsequent inactivation of the competing pathway significantly improved the 1,2-PDO yield.

Tobacco Constituents, Flavorants, and Paper Permeability of Factory-Made and Roll-Your-Own Cigarettes on the Australian Market

INTRODUCTION

Roll-your-own (RYO) tobacco is a popular choice in Australia, with some people who smoke finding these products more attractive than factory-made cigarettes (FMC). Differences in visual and tactile properties and in the feel and taste of the smoke may contribute to this attractiveness. These differences may be driven by variation in tobacco constituents and wrapping paper permeability. However, to date, there has been no comparison of RYO and FMC products on the Australian market.

AIMS AND METHODS

Chemical constituents, pH, flavorants, and paper permeability were compared in unburned RYO tobacco and tobacco from FMC. RYO and FMC products from matched brands were compared, as were products from the most popular FMC and RYO brands on the Australian market in 2018.

RESULTS

RYO tobacco had higher moisture and humectant content (glycerol and propylene glycol) than FMC tobacco. RYO tobacco also had higher amounts of total and reducing sugars and lower nicotine when comparing the most popular brands. RYO papers were less permeable than FMC papers. Both RYO and FMC tobacco contained many chemicals identified as flavorants, including fourteen with known potential health risks. For most measured constituents and flavorants, RYO tobaccos had more in common with other RYO than FMC, with the commonalities remaining even when matched brands were compared.

CONCLUSIONS

Higher levels of moisture, humectants, and sugars in Australian RYO tobacco compared to FMC may be increasing attractiveness of RYO by reducing the harsh taste of the smoke and increasing the moist feel of the tobacco.

IMPLICATIONS

While price is the main factor driving the use of RYO tobacco, some people who smoke find these products more attractive. This study has shown that Australian RYO tobacco contains higher amounts of glycerol, propylene glycol, and sugars than FMC. These chemicals may be improving the taste of the tobacco, as well as creating a moist feel that is falsely perceived as indicating that the tobacco is "fresh" and "less chemically." Ironically, it may be that higher amounts of some added chemicals in RYO contribute to false perceptions of a more natural and less harmful product.

Coaching in Competence by Design: A New Model of Coaching in the Moment and Coaching Over Time to Support Large Scale Implementation

Coaching is an increasingly popular means to provide individualized, learner-centered, developmental guidance to trainees in competency based medical education (CBME) curricula. Aligned with CBME's core components, coaching can assist in leveraging the full potential of this educational approach. With its focus on growth and improvement, coaching helps trainees develop clinical acumen and self-regulated learning skills. Developing a shared mental model for coaching in the medical education context is crucial to facilitate integration and subsequent evaluation of success. This paper describes the Royal College of Physicians and Surgeons of Canada's coaching model, one that is theory based, evidence informed, principle driven and iteratively and developed by a multidisciplinary team. The coaching model was specifically designed, fit for purpose to the postgraduate medical education (PGME) context and implemented as part of Competence by Design (CBD), a new competency based PGME program. This coaching model differentiates two coaching roles, which reflect different contexts in which postgraduate trainees learn and develop skills. Both roles are supported by the RX-OCR process: developing Relationship/Rapport, setting eXpectations, Observing, a Coaching conversation, and Recording/Reflecting. The CBD Coaching Model and its associated RX-OCR faculty development tool support the implementation of coaching in CBME. Coaching in the moment and coaching over time offer important mechanisms by which CBD brings value to trainees. For sustained change to occur and for learners and coaches to experience the model's intended benefits, ongoing professional development efforts are needed. Early post implementation reflections and lessons learned are provided.

Simultaneous medium chain carboxylic acids and 1,3-propanediol production in a bioaugmented lactate-based chain elongation induced with glycerol

The objective was to investigate the impact of the bioaugmentation on chain elongation process using glycerol, lactate and lactose as substrates in an open culture fermentation. In the batch trials the highest selectivity for chain elongation product, i.e. caproate, was observed in trials inoculated with co-culture of Megasphaera elsdenii and Eubacterium limosum grown on glycerol (28.6%), and in non-bioaugmented open culture run on lactose + lactate (14.8%). The results showed that E. limosum, out of two bioaugmented strains, was able to survive in the open culture. A continuous open culture fermentation of glycerol led to caproate and 1,3-propanediol (1,3-PDO) formation, while lactate addition led to 1,3-PDO and short chain carboxylates production. Moving the process into batch mode triggered even-carbon chain elongation. Presence of E. limosum promoted odd-carbon chain elongation and valerate production. Imaging flow cytometry combined with machine learning enabled the discrimination of Eubacterium cells from other microbial strains during the process.

Mechanical characterization of athletic helmet shells

Our purpose was to compare the mechanical properties of the protective outer shells of various athletic helmets in their final, fully manufactured form. Sections were taken from 3 different helmet shells (Bauer RE-AKT hockey helmet, Cascade R lacrosse helmet, and Riddell Speedflex football helmet) at 4 different locations (front, side, top, and rear) for a total of 12 test specimens. The 4 specimens from each helmet shell were potted together in epoxy resin moulds and mechanically polished. The hardness, elastic modulus and phase angle were measured using dynamic nanoindentation performed at 100 Hz with an oscillation amplitude of 1 nm (rms). Repeated ANOVA analysis was used to compare each of the dependent variables for each of the 3 helmets across the 4 different locations. The interaction between helmet type and location was significant for hardness (F6,63 = 2.84, P = 0.032, Pη2 = 0.21), elastic modulus (F6,63 = 6.412, P < 0.001, Pη2 = 0.38), and phase angle (F6,63 = 7.65, P < 0.001, Pη2 = 0.42). Polycarbonate has a higher ability to dissipate mechanical energy making it the recommended superior choice for helmet shells. In addition, the results lead us to speculate that manufacturing causes changes in the molecular weight or the distribution of fillers across locations for polyethylene but not for polycarbonate since mechanical properties are fairly uniform over the surface of football helmets, at least within a given helmet.

Effects of 1,3-propanediol associated, or not, with butylene glycol and/or glycerol on skin hydration and skin barrier function

OBJECTIVE

This study aimed to assess the effect of 1,3-propanediol at different concentrations (5%, 10%, or 15%), either applied alone or in combination with butylene glycol (BG) (5%) and/or glycerol (5%), on skin hydration and skin barrier function. The measurements were conducted using capacitance to determine skin hydration and trans epidermal water loss (TEWL) rates to evaluate skin barrier function.

METHODS

A total of 30 healthy female subjects participated in the study. Capacitance and TEWL measurements were conducted at multiple time points, including before application and at 15 min, 2 and 8 h after the humectants were applied to the forearms of the subjects. All the subjects provided written informed consent.

RESULTS

The 1,3-propanediol in all concentrations and in all combinations (with BG and/or glycerol) increased skin hydration and improved skin barrier function 15 min, 2 and 8 h after application. Glycerol increased the hydration performance of 1,3-propanediol. The application of 1,3-propanediol at a concentration of 15%, either alone or in combination with other humectants, reduced the TEWL to a greater extent than lower concentrations of 1,3-propanediol. Furthermore, the addition of glycerol to 1,3-propanediol 15% improved the skin barrier and reduced TEWL when compared with 1,3-propanediol alone and with the combination of 1,3-propanediol + BG.

CONCLUSION

The humectants significantly improved skin hydration and reduced TEWL throughout the 8-h time course. The increase in 1,3-propanediol concentration, as well as its combination with glycerol, provided a greater benefit to the skin, improving both hydration and the skin barrier function.

Unexpectedly stable homopurine parallel triplex of SNA:RNA*SNA and L-aTNA:RNA*L-aTNA

Homopurine strands are known to form antiparallel triplexes stabilized by G*G and A*A Hoogsteen pairs, which have two hydrogen bonds. But there has been no report on the parallel triplex formation of homopurine involving both adenosine and guanosine to the duplex. In this paper, we first report parallel triplex formation between a homopurine serinol nucleic acid (SNA) strand and an RNA/SNA duplex. Melting profiles revealed that the parallel SNA:RNA*SNA triplex was remarkably stable, even though the A*A pair has a single hydrogen bond. An L-acyclic threoninol nucleic acid (L-aTNA) homopurine strand also formed a stable parallel triplex with an L-aTNA/RNA duplex.

The combination of propylene glycol and vegetable glycerin e-cigarette aerosols induces airway inflammation and mucus hyperconcentration

Despite concerns over their safety, e-cigarettes (e-cigs) remain a popular tobacco product. Although nicotine and flavors found in e-cig liquids (e-liquids) can cause harm in the airways, whether the delivery vehicles propylene glycol (PG) and vegetable glycerin (VG) are innocuous when inhaled remains unclear. Here, we investigated the effects of e-cig aerosols generated from e-liquid containing only PG/VG on airway inflammation and mucociliary function in primary human bronchial epithelial cells (HBEC) and sheep. Primary HBEC were cultured at the air-liquid interface (ALI) and exposed to e-cig aerosols of 50%/50% v/v PG/VG. Ion channel conductance, ciliary beat frequency, and the expression of inflammatory markers, cell type-specific markers, and the major mucins MUC5AC and MUC5B were evaluated after seven days of exposure. Sheep were exposed to e-cig aerosols of PG/VG for five days and mucus concentration and matrix metalloproteinase-9 (MMP-9) activity were measured from airway secretions. Seven-day exposure of HBEC to e-cig aerosols of PG/VG caused a significant reduction in the activities of apical ion channels important for mucus hydration, including the cystic fibrosis transmembrane conductance regulator (CFTR) and large conductance, Ca2+-activated, and voltage-dependent K+ (BK) channels. PG/VG aerosols significantly increased the mRNA expression of the inflammatory markers interleukin-6 (IL6), IL8, and MMP9, as well as MUC5AC. The increase in MUC5AC mRNA expression correlated with increased immunostaining of MUC5AC protein in PG/VG-exposed HBEC. On the other hand, PG/VG aerosols reduced MUC5B expression leading overall to higher MUC5AC/MUC5B ratios in exposed HBEC. Other cell type-specific markers, including forkhead box protein J1 (FOXJ1), keratin 5 (KRT5), and secretoglobin family 1A member 1 (SCGB1A1) mRNAs, as well as overall ciliation, were significantly reduced by PG/VG exposure. Finally, PG/VG aerosols increased MMP-9 activity and caused mucus hyperconcentration in sheep in vivo. E-cig aerosols of PG/VG induce airway inflammation, increase MUC5AC expression, and cause dysfunction of ion channels important for mucus hydration in HBEC in vitro. Furthermore, PG/VG aerosols increase MMP-9 activity and mucus concentration in sheep in vivo. Collectively, these data show that e-cig aerosols containing PG/VG are likely to be harmful in the airways.

Disseminated tuberculosis associated with fingolimod treatment in a patient with multiple sclerosis

Fingolimod is a sphingosine-1-phosphate receptor modulator approved as a disease-modifying therapy (DMT) for relapsing-remitting multiple sclerosis (MS). A woman in her 30s was treated with fingolimod for relapsing-remitting MS. After 7 years of treatment, she presented with non-productive cough, night sweats, breathlessness and unintentional weight loss. She had a negative interferon-gamma release assay (IGRA). A high-resolution CT thorax showed innumerable miliary opacities in both lungs. Bronchoalveolar lavage was positive for Mycobacterium tuberculosis complex PCR. An MRI head showed multiple small punctate contrast-enhancing lesions most typical for tuberculomas. We describe the first reported case of disseminated tuberculosis (TB) associated with fingolimod treatment. Patients who are receiving DMT must be closely observed for the development of opportunistic infections, and IGRA results should be interpreted with caution. Screening for latent TB prior to commencing fingolimod should be considered on an individual basis. The management of TB in MS patients on DMT requires an interdisciplinary approach.

Biological Activity of Poly(1,3-propanediol citrate) Films and Nonwovens: Mechanical, Thermal, Antimicrobial, and Cytotoxicity Studies

Polymers are of great interest for medical and cosmeceutical applications. The current trend is to combine materials of natural and synthetic origin in order to obtain products with appropriate mechanical strength and good biocompatibility, additionally biodegradable and bioresorbable. Citric acid, being an important metabolite, is an interesting substance for the synthesis of materials for biomedical applications. Due to the high functionality of the molecule, it is commonly used in biomaterials chemistry as a crosslinking agent. Among citric acid-based biopolyesters, poly(1,8-octanediol citrate) is the best known. It shows application potential in soft tissue engineering. This work focuses on a much less studied polyester, poly(1,3-propanediol citrate). Porous and non-porous materials based on the synthesized polyesters are prepared and characterized, including mechanical, thermal, and surface properties, morphology, and degradation. The main focus is on assessing the biocompatibility and antimicrobial properties of the materials.

On recycling earth pressure balance shield muck with residual foaming agent: defoaming and antifoaming investigations

Earth pressure balance (EPB) shield is increasingly employed in metro tunnel construction, and causes a series of environmental, safety, and resource waste problems due to the disposal of a considerable amount of muck. In situ recycling of EPB shield muck is an effective solution, whereas the foam is generated by residual foaming agents used as the muck conditioning material during tunnelling, which often adsorbs clay particles and overflows the flocculation tank. To achieve defoaming and antifoaming during the reuse of muck, this study prepared novel eco-friendly silicone oil-polyether defoamers by condensation, compounding, and shear emulsification. Defoaming and antifoaming performances of different defoamers were tested using a modified Ross-Miles method and a scale model of field flocculation systems. The results indicated that a high efficiency in defoam and antifoam was characterized by chemical grafting of nano-SiO2 from silicone oils, uniform distribution and large size of grains, low viscosity, and surface tension. The defoamer dosage of 0.002-0.004 wt% near critical micelle concentration (CMC) for each defoamer is reasonable. Overall, the prepared hydroxyl silicone oil-glycerol polyoxypropylene ether (H-G) defoamer compared with other silicone oil-polyether defoamers and commercial defoamers presents the highest defoaming and antifoaming efficiency. Considering the effects of EPB shield muck, the H-G defoamer is least affected by the compound materials and increasing concentration of the commercial foaming agent. Nevertheless, the stability of the H-G emulsion system is weaker than that of the dimethyl silicone oil-glycerol polyoxypropylene ether (D-G) emulsion system after 1 month of sealed storage.

Construction of prophage-free and highly-transformable Limosilactobacillus reuteri strains and their use for production of 1,3-propanediol

The lactic acid bacterium Limosilactobacillus reuteri (formerly Lactobacillus reuteri) is a desirable host for the production of 1,3-propanediol (1,3-PDO) from glycerol when 1,3-PDO is used in the food or cosmetic industry. However, the production is hindered by strain instability, causing cell lysis, and difficult gene manipulation. This study reveals that the stability of L. reuteri DSM 20016 and its 1,3-PDO production, especially in the alcohol dehydrogenases (ADHs)-deletion mutants, are greatly enhanced after the deletion of two prophages (Φ3 and Φ4) present in the L. reuteri's chromosome. The resulting phage-free and ADHs-deletion mutant could produce >825 mM 1,3-PDO in 48 h without cell lysis at the theoretical maximum yield on glucose of ~2 mol/mol. Compared to the wild-type strain, the mutant exhibited a 45.2% increase in 1,3-PDO production titer and a 2.1-fold increase in yield. In addition, this study reports that the transformation efficiency of L. reuteri Δadh2Δadh6 mutant strains were greatly enhanced by >300-fold after the deletion of prophage Φ3, probably due to the removal of a restriction-modification (RM) system which resides in the phage genome. With improved stability and higher transformation efficiency, recombinant L. reuteri DSM 20016 Δadh2Δadh6ΔΦ3ΔΦ4 can be a more reliable and amenable host for industrial applications.

Dynamic flux balance analysis of 1,3-propanediol production by clostridium butyricum fermentation

To study the relationship between the yield of 1,3-propanediol (1,3-PDO) and the flux change of the Clostridium butyricum metabolic pathway, an optimized calculation method based on dynamic flux balance analysis was used by combining genome-scale flux balance analysis with a kinetic model. A more comprehensive and extensive metabolic pathway was obtained by optimization calculations. The primary extended branches include: the dihydroxyacetone node, which enters the pentose phosphate pathway; the α-oxoglutarate node, which has synthetic metabolic pathways for glutamic acid and amino acids; and the serine and homocysteine nodes, which produce cystathionine before homocysteine enters the methionine cycle pathway. According to the expanded metabolic network, the flux distribution of key nodes in the metabolic pathway and the relationship between the flux distribution ratio of nodes and the yield of 1,3-PDO were analyzed. At the dihydroxyacetone node, the flux of dihydroxyacetone converted to dihydroxyacetone phosphate was positively correlated with the yield of 1,3-PDO. As an important intermediate product, the flux change in the metabolic pathway of α-oxoglutarate reacting with amino acids to produce glutamic acid is positively correlated with the yield. When pyruvate was used as the central node to convert into lactic acid and α-oxoglutarate, the proportion of branch flux was negatively correlated with the yield of 1,3-PDO. These studies provide a theoretical basis for the optimization and further study of the metabolic pathway of C. butyricum.

Pure Covalent-Organic Framework Membrane as a Label-Free Biomimetic Nanochannel for Sensitive and Selective Sensing of Chiral Flavor Substances

Chiral flavor substances play an important role in the human perception of different tastes. Here, we report a pure covalent-organic framework (COF) membrane nanochannel in combination with a chiral gold nanoparticles (AuNPs) selector for sensing chiral flavor substances. The pure COF membrane with a proper pore size is selected as the nanochannel, while l-cysteine-modified AuNPs (l-Cys-AuNPs) are used as the chiral selector. l-Cys-AuNPs show stronger binding to the S-enantiomer than the R-enantiomer, causing current reduction to different degrees for the R- and S-enantiomer to achieve chiral sensing due to the synergistic effect of the size exclusion of the COF nanochannel and the chiral selectivity of l-Cys-AuNPs. The developed COF membrane nanochannel sensing platform not only allows an easy balance of the permeability and selectivity, which is difficult to achieve in traditional polymer membrane nanochannel sensors, but also exhibits better chiral performance than commercial artificial anodic aluminum oxide (AAO) nanochannel sensors. The developed nanochannel sensor is successfully applied for sensing flavor enantiomers such as limonene, propanediol, methylbutyric acid, and butanol with the enantiomer excess values of 55.2% (propanediol) and 72.4% (limonene) and the low detection limits of 36 (limonene) and 71 (propanediol) ng L-1. This study provides a new idea for the construction of nanochannel platforms based on the COF for sensitive and selective chiral sensing.

Felbamate urolithiasis

Drug-induced nephrolithiasis is an important consideration in recurrent stone formers with polypharmacy. While felbamate nephrolithiasis has previously been published in the paediatric population, we present the oldest published case of a felbamate stone in an adult, a man in his 30s with Lennox-Gastaut syndrome. Even with moderate dosing, high drug serum levels can occur. Performing at least one stone analysis remains a critical component to care in these patients. Urologists should have a high index of suspicion for drug stone when stone analysis returns indeterminate characterisation in the absence of infection. Close communication with neurology is key to preventing recurrent stone disease.

Synthesis and Characterization of Poly(Butylene Sebacate-Co-Terephthalate) Copolyesters with Pentaerythritol as Branching Agent

Poly(butylene sebacate-co-terephthalate) (PBSeT) copolyesters are prepared by melt polymerization via two-step transesterification and polycondensation using pentaerythritol (PE) as a branching agent. The effects of the incorporated PE on its chemical, thermal, mechanical, and degradation properties, along with the rheological properties of its melt, are investigated. The highest molecular weight and intrinsic viscosity along with the lowest melt flow index were achieved at a PE content of 0.2 mol%, with minimal reduction in the tensile strength and the highest tear strength. The addition of PE did not significantly influence the thermal behavior and stability of the PBSeT copolyesters; however, the elongation at break decreased with increasing PE content. The sample with 0.2 mol% PE exhibited a higher storage modulus and loss modulus as well as a lower loss angle tangent than the other samples, indicating improved melt elasticity. The incorporation of more than 0.2 mol% PE enhanced the enzymatic degradation of copolyesters. In summary, including within 0.2 mol%, PE effectively improved both the processability-related characteristics and degradation properties of PBSeT copolyesters, suggesting their potential suitability for use in agricultural and packaging materials.

Propylene glycol inactivates respiratory viruses and prevents airborne transmission

Viruses are vulnerable as they transmit between hosts, and we aimed to exploit this critical window. We found that the ubiquitous, safe, inexpensive and biodegradable small molecule propylene glycol (PG) has robust virucidal activity. Propylene glycol rapidly inactivates a broad range of viruses including influenza A, SARS-CoV-2 and rotavirus and reduces disease burden in mice when administered intranasally at concentrations commonly found in nasal sprays. Most critically, vaporised PG efficiently abolishes influenza A virus and SARS-CoV-2 infectivity within airborne droplets, potently preventing infection at levels well below those tolerated by mammals. We present PG vapour as a first-in-class non-toxic airborne virucide that can prevent transmission of existing and emergent viral pathogens, with clear and immediate implications for public health.

PPG-11 and PPG-15 Stearyl Ether

The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2001, along with updated information regarding product types and concentrations of use, and confirmed that PPG-11 and PPG-15 Stearyl Ether are safe as cosmetic ingredients in the practices of use and concentration as described in this report.

Chronic larval and adult honey bee laboratory testing: Which dietary additive should be considered when a test substance is not solubilized in acetone?

Chronic toxicity tests on adult and larval honey bees (Apis mellifera) can require the use of dietary additives (solvents, emulsifiers, adjuvants and viscosifier agents) when the active ingredient of plant protection products cannot be dissolved or does not remain stable and homogeneous within the test diets. Acetone is the widely used and accepted solvent allowed within the international regulatory guidelines, but it can be ineffective in keeping certain compounds in solution and can cause toxicity to adults and larvae. In this publication, we present an evaluation of alternative additives in adult and larval diets. Six dietary additives including five solvents (ethanol, isopropanol, n-propanol, propylene glycol and triethylene glycol) and a viscosifier agent (xanthan gum) at five concentrations along with a negative control and a solvent control (acetone) were investigated at seven laboratories. The safe levels for bees were determined for each of the additives used in the 10-day chronic adult and 22-day chronic larval tests. In the 10-day chronic adult study, ethanol and isopropanol were found to be safe at concentrations ≤ 5.0 %, while xanthan gum can be reliably used at concentrations ≤ 0.1 %. Greater variability across laboratories was observed for N-propanol, propylene glycol, and triethylene glycol and these agents may cause mortality when added to diets at concentrations above 0.25-0.5 %. The safe levels of additives to larval diet in the 22-day chronic larval test had a greater variability and were generally lower than what were observed for adult diet. Our results do not recommend the inclusion of ethanol or n-propanol into the larval diet, and isopropanol, propylene glycol, and triethylene glycol may cause mortality at concentrations above 0.25-0.5 %. Safe levels for xanthan gum were more variable than what was observed for adults, but it can be used reliably at concentrations ≤ 0.05 %. Our analyses conclude that several additives can be integrated successfully in honey bee laboratory bioassays at levels that cause low mortality to adults and larvae.

Formulation of Aloe vera based curcumin topical gel and its in-vitro evaluation

Curcumin is a polyphenolic compound obtained from the rhizome of plant. Curcuma longa possesses antioxidant, anti-inflammatory and wound-healing properties. The current study was designed to formulate an Aloe vera-based curcumin topical gel. To enhance curcumin's solubility, it was first complexed with β-cyclodextrin, given its hydrophobic nature. While Carbopol, carboxy methyl cellulose and guar gum were used in various concentrations as gelling agents for preparation of the formulations. The effect of propylene glycol as a permeation enhancer was also observed. The prepared formulations were tested for different parameters such as physical appearance, spreadability, drug content, pH, viscosity and in-vitro permeation. All the formulations were found to be stable. All formulations consisting of propylene glycol showed permeation within the range of 80-90%. The maximum percentage of drug release was observed in the formulation containing 1% Carbopol 940 as the gelling agent which also exhibited good spreadability. In comparison to gels formulated with carboxymethyl cellulose and guar gum, Carbopol 940 gels appeared more translucent. Consequently, it was concluded that curcumin's permeation improved following its complexation with β-cyclodextrin. This complex when further used for the formation of an aloe vera based topical gel with 1% Carbopol 940 and 10% propylene glycol demonstrated maximum efficacy.

Enhancing the Sound and Thermal Insulation Properties of Polypropylene Foam by Preparing High Melt Strength Polypropylene

High-performance polypropylene (PP) foam is a vital polymer product in industrial areas. However, the poor melt strength of ordinary PP homopolymer limits its foaming molding. In this work, high melt strength polypropylene (HMSPP) is prepared by using styrene (St) and tripropylene glycol diacrylate (TPGDA) as comonomers, and then PP foams are prepared by mold foaming method. The results show that adding St in the grafting process of TPGDA will obviously improve the melt strength of the PP matrix, and its melt strength (28 184 Pa.s) is 7.4 times higher than that of pure PP. HMSPP foam has more regular and uniform cells and higher cell density, which significantly improves the sound and thermal insulation properties of PP foam. Compared with pure PP foam, the average sound transmission loss (52.9 dB) of HMSPP foam with a low foaming ratio increased by 64%, and the thermal conductivity (0.0867 W mK-1 ) decreased by 46%. Therefore, the obtained HMSPP foam can be used in sound insulation or thermal insulation area. This work provides an available route for the high-performance utilization of PP foam.

Fermentation of biodiesel-derived crude glycerol to 1,3-propanediol with bio-wastes as support matrices: Polynomial prediction model

Biodiesel production from used cooking oil is sustainable alternative, for bio-energy production. The process generates residual crude glycerol (RCG) as the major energy-rich waste which can be used to produce various bio-based chemicals like 1,3-propanediol (1,3-PDO) through biotechnological interventions. This RCG contains several impurities like methanol, soap, organic materials, salts non-transesterified fatty acids and metals in varied concentrations. These impurities significantly affect yield and productivity of the bio-process due to their marked microbial toxicity. In this work, previously isolated Clostridium butyricum L4 was immobilized on various abundantly available cheap bio-wastes (like rice straw, activated carbon and corn cob) to explore advantages offered and improve tolerance to various feed impurities. Amongst these, shredded rice straw was found most suitable candidate for immobilization and results in maximum improvement in 1,3-PDO production (18.4%) with highest porosity (89.28%), lowest bulk density (194.48Kg/m3), and highest cellular biofilm density (CFU/g-8.4 ×1010) amongst the three matrices. For practical purposes, recyclability was evaluated and it was concluded that even after reusing for five successive cycles the production retained to ∼82.4%. Subsequently, polynomial model was developed using 30 runs central composite factorial design experiments having coefficient of regression (R²) as 0.9520, in order to predict yields under different immobilization conditions for 1,3-PDO production. Plackett-Burman was employed (Accuracy= 99.17%) to screen significant toxic impurities. Based on statistical analysis six impurities were found to be significantly influential on PDO production in adverse manner. With negative coefficient of estimate (COE) varying in decreasing order: Linoleic acid >Oleic acid >Stearic acid >NaCl>K2SO4 >KCl. The study illustrates practical application for repurposing waste glycerol generated from biodiesel plants, thus developing improved agnostic process along with yield production models.

In vitro cytotoxic effect of stigmasterol derivatives against breast cancer cells

BACKGROUND

Stigmasterol is an unsaturated phytosterol that belong to the class of tetracyclic steroids abundant in Rhoicissus tridentata. Stigmasterol is an important constituent since it has shown impressive pharmacological effects such as anti-osteoarthritis, anticancer, anti-diabetic, anti-inflammatory, antiparasitic, immunomodulatory, antifungal, antioxidant, antibacterial, and neuroprotective activities. Furthermore, due to the presence of π system and hydroxyl group, stigmasterol is readily derivatized through substitution and addition reactions, allowing for the synthesis of a wide variety of stigmasterol derivatives.

METHODS

Stigmasterol (1) isolated from Rhoicissus tridentata was used as starting material to yield eight bio-active derivatives (2-9) through acetylation, epoxidation, epoxide ring opening, oxidation, and dihydroxylation reactions. The structures of all the compounds were established using spectroscopic techniques, NMR, IR, MS, and melting points. The synthesized stigmasterol derivatives were screened for cytotoxicity against the hormone receptor-positive breast cancer (MCF-7), triple-negative breast cancer (HCC70), and non-tumorigenic mammary epithelial (MCF-12 A) cell lines using the resazurin assay.

RESULTS

Eight stigmasterol derivatives were successfully synthesized namely; Stigmasterol acetate (2), Stigmasta-5,22-dien-3,7-dione (3), 5,6-Epoxystigmast-22-en-3β-ol (4), 5,6-Epoxystigmasta-3β,22,23-triol (5), Stigmastane-3β,5,6,22,23-pentol (6), Stigmasta-5-en-3,7-dion-22,23-diol (7), Stigmasta-3,7-dion-5,6,22,23-ol (8) and Stigmast-5-ene-3β,22,23-triol (9). This is the first report of Stigmasta-5-en-3,7-dion-22,23-diol (7) and Stigmasta-3,7-dion-5,6,22,23-ol (8). The synthesized stigmasterol analogues showed improved cytotoxic activity overall compared to the stigmasterol (1), which was not toxic to the three cell lines tested (EC50 ˃ 250 µM). In particular, 5,6-Epoxystigmast-22-en-3β-ol (4) and stigmast-5-ene-3β,22,23-triol (9) displayed improved cytotoxicity and selectivity against MCF-7 breast cancer cells (EC50 values of 21.92 and 22.94 µM, respectively), while stigmastane-3β,5,6,22,23-pentol (6) showed improved cytotoxic activity against the HCC70 cell line (EC50: 16.82 µM).

CONCLUSION

Natural products from Rhoicissus tridentata and their derivatives exhibit a wide range of pharmacological activities, including anticancer activity. The results obtained from this study indicate that molecular modification of stigmasterol functional groups can generate structural analogues with improved anticancer activity. Stigmasterol derivatives have potential as candidates for novel anticancer drugs.

Consequences of poly(ethylene oxide) and poloxamer P188 on transcription in healthy and stressed myoblasts

Poly(ethylene oxide) (PEO) and poloxamers, a class of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers, have many personal and medical care applications, including the stabilization of stressed cellular membranes. Despite the widespread use, the cellular transcriptional response to these molecules is relatively unknown. C2C12 myoblasts, a model muscle cell, were subjected to short-term Poloxamer 188 (P188) and PEO181 (8,000 g/mol) treatment in culture. RNA was extracted and sequenced to quantify transcriptomic impact. The addition of moderate concentrations (14 µM) of either polymer to unstressed cells caused substantial differential gene expression, including at least twofold modulation of 357 and 588 genes, respectively. In addition, evaluation of the transcriptome response to osmotic stress without polymer treatment revealed dramatic change in RNA expression. Interestingly, the addition of polymer to stressed cells-at concentrations that provide physiological protection-did not yield a significant difference in expression of any gene relative to stress alone. Genome-scale expression analysis was corroborated by single-gene quantitative real-time PCR. Changes in protein expression were measured via western blot, which revealed partial alignment with the RNA results. Collectively, the significant changes to expression of multiple genes and resultant protein translation demonstrates an unexpectedly broad biochemical response to these polymers in healthy myoblasts in vitro. Meanwhile, the lack of substantial transcriptional response to polymer treatment in stressed cells highlights the physical nature of that protective mechanism.

E-cigarette aerosols of propylene glycol impair BK channel activity and parameters of mucociliary function

Propylene glycol (PG) is a common delivery vehicle for nicotine and flavorings in e-cigarette (e-cig) liquids and is largely considered safe for ingestion. However, little is known about its effects as an e-cig aerosol on the airway. Here, we investigated whether pure PG e-cig aerosols in realistic daily amounts impact parameters of mucociliary function and airway inflammation in a large animal model (sheep) in vivo and primary human bronchial epithelial cells (HBECs) in vitro. Five-day exposure of sheep to e-cig aerosols of 100% PG increased mucus concentrations (% mucus solids) of tracheal secretions. PG e-cig aerosols further increased the activity of matrix metalloproteinase-9 (MMP-9) in tracheal secretions. In vitro exposure of HBECs to e-cig aerosols of 100% PG decreased ciliary beating and increased mucus concentrations. PG e-cig aerosols further reduced the activity of large conductance, Ca2+-activated, and voltage-dependent K+ (BK) channels. We show here for the first time that PG can be metabolized to methylglyoxal (MGO) in airway epithelia. PG e-cig aerosols increased levels of MGO and MGO alone reduced BK activity. Patch-clamp experiments suggest that MGO can disrupt the interaction between the major pore-forming BK subunit human Slo1 (hSlo1) and the gamma regulatory subunit LRRC26. PG exposures also caused a significant increase in mRNA expression levels of MMP9 and interleukin 1 beta (IL1B). Taken together, these data show that PG e-cig aerosols cause mucus hyperconcentration in sheep in vivo and HBECs in vitro, likely by disrupting the function of BK channels important for airway hydration.

Anti-diabetic, anti-inflammatory and muscle relaxant activities of extracts from Spirogyra varians (Hassall) Kuetzing

Spirogyra varians (Hassall) Kuetzing is one of the edible freshwater filamentous green algae. This alga is commonly used as local food in northern and northeastern Thailand. A study on pharmacological activities of S. varians has not yet been extensively performed. Therefore, this study was established to investigate the anti-diabetic, anti-inflammatory and muscle relaxant activities of the extracts from S. varians. The In vitro α-glucosidase inhibition assay revealed that the propylene glycol extract exhibited the highest α-glucosidase inhibition activity compared to the methanol and ethanol extracts. However, all the extracts possess α-glucosidase inhibition activity less potent than Acarbose, an α-glucosidase inhibitor. The propylene glycol extract showed the highest inhibition of nitric oxide production in LPS-stimulated RAW 264.7 macrophage cells compared to the methanol and ethanol extracts. Nevertheless, the inhibition activity of the extracts was less potent than diclofenac, an anti-inflammatory drug. Whereas, the methanol extract exhibited the highest muscle relaxant activity on frog gastrocnemius compared to the ethanol and propylene glycol extracts. The methanol extract displayed muscle relaxant activity with a similar potent to Indomethacin, a pain relief drug. This study indicates that S. varians can be used as an effective novel natural resource for developing anti-diabetic, anti-inflammatory and muscle relief agents.

Genome-Scale Modeling and Systems Metabolic Engineering of Vibrio natriegens for the Production of 1,3-Propanediol

The fastest-growing bacterium Vibrio natriegens is a highly promising next-generation workhorse for molecular biology and industrial biotechnology. In this work, we described the workflows for developing genome-scale metabolic models and genome-editing protocols for engineering Vibrio natriegens. A case study for metabolic engineering of Vibrio natriegens for the production of 1,3-propanediol was also presented.

Passive exposure to electronic cigarette aerosol in pregnancy: A case study of a family

BACKGROUND

Passive exposure to the aerosols of electronic cigarettes (e-cigarettes) has been little studied. We assessed this exposure in late pregnancy in a woman and her 3-year-old child, exposed through e-cigarette use by another household member.

METHODS

This prospective longitudinal case study involved a family unit consisting of an e-cigarette user, a pregnant woman who delivered an infant during the study, and the couple's older 3-year-old son. At 31, 36, and 40 weeks of the pregnancy, we measured biomarkers (nicotine metabolites, tobacco-specific nitrosamines, propanediols, glycerol, and metals) in the urine and hair of all three participants and in the saliva of the adults, in cord blood at delivery, and in the breast milk at the postpartum period.

RESULTS

Samples from the e-cigarette user showed quantifiable concentrations of all analytes assessed (maximum urinary cotinine concentration, 4.9 ng/mL). Among samples taken from the mother, nicotine and its metabolites were found mainly in urine and also in saliva and hair, but not in cord blood. During the postpartum period, we found cotinine concentrations of 2.2 ng/mL in the mother's urine and 0.22 ng/mL in breast milk; 1,2-propanediol was generally detected in urine and saliva, but not in cord blood or breast milk. The maximum urinary cotinine concentration in the 3-year-old child was 2.6 ng/mL and propanediols also were detected in his urine. Nitrosamines were not detected in samples taken from the mother or the 3-year-old. Metals found in the refill liquid were detected at low levels in both the mother and the 3-year-old.

CONCLUSIONS

We detected low but not negligible concentrations of e-cigarette-related analytes (including cord blood and breast milk) in an exposed pregnant non-user and in a 3-year-old child also living in the home. Passive exposure to e-cigarette aerosols cannot be disregarded and should be assessed in larger observational studies.

The influence of UV irradiation on fish skin collagen films in the presence of xanthohumol and propanediol

Fish skin collagen films are widely used as adhesives in medicine and cosmetology. Ultraviolet (UV) irradiation can be considered as an effective sterilization method for biomaterials, however, it may also lead to material photodegradation. In this work, the influence of xanthohumol and propanediol on the physico-chemical properties of collagen films before and after UV irradiation was studied. Collagen for this research was extracted from silver carp skin and thin films were fabricated by the solution casting methods. The structure of films was researched using infrared spectroscopy. The surface properties of films were investigated using Atomic Force Microscopy (AFM) and contact angle measurements. Mechanical properties were measured as well. It was found that the addition of xanthohumol and propanediol modified the roughness of collagen films and their mechanical properties. UV irradiation led to the water loss from the film and modification of the collagen structure. In the presence of propanediol and xanthohumol the water loss after UV irradiation was smaller than in UV-irradiated collagen films without these additives.

Evaluation of propylene glycol methyl ether as a potential challenge agent for leak detection of liquid and headspace from closed system drug transfer devices using Fourier transform infrared spectroscopy

Choosing an appropriate surrogate of hazardous drugs for use in testing Closed System Drug-Transfer Devices (CSTDs) is a challenging endeavor with many factors that must be considered. It was suggested that the compound propylene glycol methyl ether (PGME) may meet many of the criteria we considered important in a suitable surrogate. Criteria included sufficient volatility to evaporate from aqueous liquid leaks efficiently, a Henry's constant which produced sufficient vapor phase concentrations to make headspace leaks detectable, and suitability for detection using a low-cost detection system. We evaluated the measurement of vapors from solutions containing PGME released inside a closed chamber. We present data used to quantify limits of detection, limits of quantification, bias, precision, and accuracy of Fourier Transform Infrared Spectroscopy (FTIR) measurements of vapors from 2.5 M PGME solutions. The effects of ethanol as a component of the PGME solution were also evaluated. Liquid drops of PGME solutions and headspace vapors above PGME solutions were released to simulate leaks from CSTDs. Using a calibration apparatus, an instrumental limit of detection (LOD) of 0.25 ppmv and a limit of quantitation (LOQ) of 0.8 ppmv were determined for PGME vapor. A LOD of 1.1 μL and a LOQ of 3.5 μL were determined for liquid aliquots of 2.5 M PGME solution released in a closed chamber. Accurate quantitation of liquid leaks required complete evaporation of droplets. With the upper end of the useable quantitation range limited by slow evaporation of relatively large droplets and the lower end defined by the method LOQ, the method evaluated in this research had a narrow quantitative range for liquid droplets. Displacement of 45 mL of vial headspace containing PGME vapor is the largest amount expected when using the draft NIOSH testing protocol. Release of an unfiltered 45 mL headspace aliquot within the NIOSH chamber was calculated to produce a concentration of 0.8 ppmv based on the Henry's constant, which is right at the instrumental LOQ. Therefore, the sensitivity of the method was not adequate to determine leaks of PGME vapor from a headspace release through an air filtering CSTD when using the draft NIOSH testing protocols with an FTIR analyzer.

Electronic Cigarette Use, Misuse, and Harm

Electronic cigarettes (e-cigarettes) are battery-powered devices that use heat to aerosolize a liquid containing a variety of substances (usually nicotine and/or cannabinoids, flavorings, and glycerol or propylene glycol base) that is then inhaled. E-cigarettes are rapidly evolving over time, so the true health effects of e-cigarettes are difficult to study and remain largely unknown. We review the effects of e-cigarettes on nicotine addiction and on pulmonary disease including the effects of dual use and switching from combustible cigarettes to e-cigarettes. Studies show that e-cigarette use can increase the risk to nicotine dependence and combustible tobacco use. Studies show an association between e-cigarette use and pulmonary disease. Some studies suggest reduced harm from e-cigarette use compared with smoking, but this requires further study. Most adults who use e-cigarettes also smoke cigarettes; epidemiologic studies suggest that the combination of e-cigarettes and cigarettes is more harmful than using either product alone.

Improving tolerance and 1,3-propanediol production of Clostridium butyricum using physical mutagenesis, adaptive evolution and genome shuffling

Bioconversion efficiency of glycerol to 1,3-propanediol (1,3-PD) by Clostridium butyricum is bottlenecked by its low tolerance to various stressors, especially glycerol as the substrate, 1,3-PD as the end product, and butyric acid as a by-product, which eventually decreases 1,3-PD yield. This study aimed at improving the tolerance and 1,3-PD production capability of C. butyricum using random mutagenesis and evolutionary techniques. Mutagenesis of wild strain by atmospheric room temperature plasma (ARTP) provided the first population with maximum tolerance to 160 g/L glycerol, while microbial microdroplet culture system (MMC)-mediated adaptive laboratory evolution (ALE) generated the second population with tolerance to 100 g/L 1,3-PD. Subsequently, genome shuffling of both populations yielded a final strain, GJH-418, which generated 60.12 g/L1,3-PD with a productivity of 1.72 g/L/h. The transcript analysis of the mutant and wild strains revealed the possible involvement of 8 genes in high tolerance and high 1,3-PD production through either up- or down-regulation.

Selectivity and kinetic modeling of penicillin G acylase variants for the synthesis of cephalexin under a broad range of substrate concentrations

The kinetics of cephalexin synthesis and hydrolysis of the activated acyl-donor precursor phenylglycine methyl ester (PGME) were characterized under a broad range of substrate concentrations. A previously developed model by Youshko-Svedas involving the formation of the acyl-enzyme complex followed by binding of the nucleophilic β-lactam donor does not fully estimate the maximum reaction yields for cephalexin synthesis at different concentrations using initial-rate data. 7-aminodesacetoxycephalosporanic acid (7-ADCA) was discovered to be a potent inhibitor of cephalexin hydrolysis, which may account for the deviation from model predictions. Three kinetic models were compared for cephalexin synthesis, with the model incorporating competitive inhibition due to 7-ADCA yielding the best fit. Additionally, the βF24A variant and Assemblase® did not exhibit significantly different kinetics for the synthesis of cephalexin compared to the wild-type, for the concentration range evaluated and for both initial-rate experiments and time-course synthesis experiments. Lastly, a continuous stirred-tank reactor for cephalexin synthesis was simulated using the model incorporating competitive inhibition by 7-ADCA, with clear tradeoffs observed between productivity, fractional yield, and PGME conversion.

Identification and semi-quantification of metabolites of new plasticizers in urine collected from flemish adults and children

A suspect screening workflow combined with a semi-quantification method was applied for the investigation of metabolites of the plasticizers di-propylene glycol dibenzoate (DiPGDB) and tri-n-butyl trimellitate (TBTM) in human urine collected from adults and children during winter (W) and summer (S) seasons. Liquid chromatography - quadrupole time of flight mass spectrometry (LC-QTOF-MS) was applied for the analyses. Two direct and one indirect metabolites of DiPGDB were identified: 3-(3-hydroxypropoxy) propyl benzoate (DiPGDB-M194), 3,4,5-trihydroxy-6-[3-(3-hydroxypropoxy) propoxy] oxane-2-carboxylic acid (DiPGDB-M310), hippuric acid (DiPGDB-M179) and one metabolite of TBTM: bis(butoxycarbonyl) benzoyloxy]-3,4,5-trihydroxyoxane-2-carboxylic acid (TBTM-M498). The identified metabolites were reported with levels of confidence (LoC) 2 and 3 and their concentrations were assessed using a semi-quantification approach. The respective concentration ranges for W and S samples were 0.20-42 ng/mL and 0.07-29 ng/mL for DiPGDB-M194, 2.5-1420 ng/mL and 5.0-2320 ng/mL for DiPGDB-M310, 230-10840 ng/mL and 320-8420 ng/mL for DiPGDB-M179, and 0.40-30 ng/mL and 0.65-30 ng/mL for TBTM-M498. The detection frequency order in urine samples was DiPGDB-M310 = DiPGDB-M179 (100%) >TBTM-M498 (44%) > DiPGDB-M194 (28%) for W and DiPGDB-M179 (99%)> DiPGDB-M310 (98%) > TBTM-M498 (57%) > DiPGDB-M194 (30%) for S. The identified metabolites DiPGDB-M310, DiPGDB-M194 and TBTM-M498 are potential biomarkers for the evaluation of human exposure to DiPGDB and TBTM. DiPGDB-M179 cannot be used for the same purpose due to its formation from compounds with multi-source origin. The application of the semi-quantification method could be useful for further studies where analytical standards are not available.

Novel selective "on-off" fluorescence sensor based on julolidine hydrazone-Al3+ complex for Cu2+ ion: DFT study

A hydrazone (T1) was synthesized by reacting 8-hydroxyjulolidine-9-carboxaldehyde with 2-furoic hydrazide and then modified with Al³⁺ ion to form a novel hydrazone Al³⁺ complex (T1-Al³⁺) in an aqueous solution (8% propylene glycol in 10 mM HEPES pH 5.5). The T1-Al³⁺ complex was studied as a Cu²⁺ selective sensor due to its highly efficient capacibility of paramagnetic quenching. The results showed that the T1-Al³⁺ complexed sensor possesses remarkable sensitivity and selectivity for Cu²⁺ ion in 8% propylene glycol in 10 mM HEPES pH 5.5 as compared with other tested analytes. Notably, this sensor has a broad linear detection range of 10-110 µM for Cu²⁺ ion and a detection limit level of 0.62 µM, which is lower than the Cu²⁺ concentration threshold in drinking water designated by the United States Environmental Protection Agency (EPA). Additionally, it was detectable for the presence of Cu²⁺ ion in mineral water and tap water samples. The selectivity of T1-Al³⁺ complexed sensor with Cu²⁺ ion could be explained by the basis of computation with Gaussian software complied with the basis sets of B3LYP/6-31 G(d,p)/LANL2DZ. Furthermore, only T1 exhibited anticancer efficacy against HeLa and U251 cells with MTT assay.

Optimization of ultrasound-assisted extraction of bioactive compounds from coffee pulp using propylene glycol as a solvent and their antioxidant activities

In the cosmetic and pharmaceutical industries, it has been increasingly popular to use alternative solvents in the extraction of bioactive compounds from plants. Coffee pulp, a by-product of coffee production, contains different phenolic compounds with antioxidant properties. The effects of polyols, amplitude, extraction time, solvent concentration, and liquid-solid ratio on total phenolic content (TPC) using ultrasound-assisted extraction (UAE) were examined by single-factor studies. Three main factors that impact TPC were selected to optimize the extraction conditions for total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), and their antioxidant activities using the Box-Behnken design. Different extraction methods were compared, the bioactive compounds were identified and quantified by liquid chromatography triple quadrupole mass spectrometer (LC-QQQ), and the cytotoxicity and cellular antioxidant activities of the extract were studied. According to the response model, the optimal conditions for the extraction of antioxidants from coffee pulp were as follows: extraction time of 7.65 min, liquid-solid ratio of 22.22 mL/g, and solvent concentration of 46.71 %. Under optimized conditions, the values of TPC, TFC, TTC, 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging assay, 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging assay, and Ferric reducing antioxidant power assay (FRAP) were 9.29 ± 0.02 mg GAE/g sample, 58.82 ± 1.38 mg QE/g sample, 8.69 ± 0.25 mg TAE/g sample, 7.56 ± 0.27 mg TEAC/g sample, 13.59 ± 0.25 mg TEAC/g sample, and 10.90 ± 0.24 mg FeSO₄/g sample, respectively. Compared with other extraction conditions, UAE with propylene glycol extract (PG-UAE) was significantlyhigher in TPC, TFC, TTC, DPPH, ABTS, and FRAP response values than UAE with ethanol (EtOH-UAE), maceration with propylene glycol (PG-maceration), and maceration with ethanol (EtOH -maceration) (p < 0.05). Major bioactive compounds detected by LC-QQQ included chlorogenic acid, caffeine, and trigonelline. At higher concentrations starting from 5 mg/ml, PG-UAE extract showed higher cell viability than EtOH-UAE in both cytotoxicity and cellular antioxidant assays. The researcher expects that this new extraction technique developed in this work could produce a higher yield of bioactive compounds with higher biological activity. Therefore, they can be used as active ingredients in cosmetics (anti-aging products) and pharmaceutical applications (food supplements, treatment for oxidative stress-related diseases) with minimal use of chemicals and energy.

Construction of sublingual trilaminated Eszopiclone fast dissolving film for the treatment of Insomnia: Formulation, characterization and In vivo clinical comparative pharmacokinetic study in healthy human subjects

Background

Disturbed sleep can cause to m health problems such as cognitive impairment, depressed mood, and negative effects on cardiovascular, endocrine, and immune function. This study formulates and optimizes Eszopiclone trilaminate fast dissolving film.

Methods

Prepared Eszopiclone trilaminate fast dissolving film (Eszopiclone TFDF) was characterized by disintegration time, drug release, tensile strength (TS), percentage elongation (EB%), folding endurance, taste masking test, and in vitro dissolution test. The selected formulas were F2 (0.5% xanthan gum, 10% propylene glycol), F4 (3% sodium alginate, 10% propylene glycol) and F6 (1.5% pullulan, 10% propylene glycol) were subjected to in vivo study compared to conventional Lunesta® tablet.

Results

The results indicated that disintegration time was in the range of 940 m. Drug release was found to be in the field of 78.51%–99.99%, while TS values and EB% differed from 11.12 to 25.74 (MPa) and 25.38%–36.43%, respectively. The folding endurance went between 200 and 300 times. All formulas exhibited acceptable uniformity content, surface pH, film thickness, and a good taste feeling.

Conclusion

F4 had the highest Cmax (39.741 ± 6.785-μg/l) and lower Tmax (1.063 hr) among other formulas and conventional tablets. Therefore, FDFs’ technology could increase the therapeutic effect of Eszopiclone.

Fermentative reforming of crude glycerol to 1,3-propanediol using Clostridium butyricum strain L4

Repurposed used cooking oil is a sustainable alternative to other feedstocks for biodiesel production offering enviro-economic benefits. Residual crude glycerol (RCG) from such biodiesel production plants is difficult to utilize due to presence of numerous toxic impurities with various inhibitory effects on biological fermentative reforming process. However, it is a new industrial feedstock for bio-based production of 1,3-propanediol. In this work, a new Clostridium butyricum strain L4 was isolated from biogas reactor leachate after rigorous adaption and 35 subcultures under increasing stress conditions and studied for green production of 1,3-propanediol (PDO) from RCG and further process development. Evaluation of fermentative reforming kinetics was performed and the optimal reaction conditions are pH 7.0, temperature 30 °C, 2 g yeast extract/L and 15 g ammonium sulphate/L. Glycerol-glucose co-fermentation (10:1) enhanced cell growth and thus, PDO output by 11.6 g/L. In comparison to batch fermentation (24.8 g PDO/L; 0.58 mol PDO/mol glycerol) there was 2.8-fold improvement with fed-batch process resulting in accumulation of 70.1 g PDO/L (Yield = 0.65 mol PDO/mol glycerol) using the studied biocatalyst in 150 h. In order to predict yields under different operational conditions a multiple linear regression model was developed (r² = 0.783) with six independent variables (p < 0.05), where biomass (g/L) and temperature (^oC) were forecasted as top contributors to PDO yield. Finally, this biocatalyst appears as a potential candidate for industrial use due to its non-pathogenic nature, ability to grow in wide pH and temperature conditions, tolerance to high substrate and product concentration, insignificant generation of by-products and Coenzyme B12 independent biotransformation. The study can add value to bio-utilization of RCG to produce green 1,3-propanediol.