Role of Unimers to Polymersomes Transition in Pluronic Blends for Controlled and Designated Drug Conveyance.

This study investigates the nanoscale self-assembly from mixtures of two symmetrical poly(ethylene oxide)-poly(propylene oxide)-pol(ethylene oxide) (PEO-PPO-PEO) block copolymers (BCPs) with different lengths of PEO blocks and similar PPO blocks. The blended BCPs (commercially known as Pluronic F88 and L81, with 80 and 10% PEO, respectively) exhibited rich phase behavior in an aqueous solution. The relative viscosity (ηrel) indicated significant variations in the flow behavior, ranging from fluidic to viscous, thereby suggesting a possible micellar growth or morphological transition. The tensiometric experiments provided insight into the intermolecular hydrophobic interactions at the liquid-air interface favoring the surface activity of mixed-system micellization. Dynamic light scattering (DLS) and small-angle neutron scattering (SANS) revealed the varied structural morphologies of these core-shell mixed micelles and polymersomes formed under different conditions. At a concentration of ≤5% w/v, Pluronic F88 exists as molecularly dissolved unimers or Gaussian chains. However, the addition of the very hydrophobic Pluronic L81, even at a much lower (<0.2%) concentration, induced micellization and promoted micellar growth/transition. These results were further substantiated through molecular dynamics (MD) simulations, employing a readily transferable coarse-grained (CG) molecular model grounded in the MARTINI force field with density and solvent-accessible surface area (SASA) profiles. These findings proved that F88 underwent micellar growth/transition in the presence of L81. Furthermore, the potential use of these Pluronic mixed micelles as nanocarriers for the anticancer drug quercetin (QCT) was explored. The spectral analysis provided insight into the enhanced solubility of QCT through the assessment of the standard free energy of solubilization (ΔG°), drug-loading efficiency (DL%), encapsulation efficiency (EE%), and partition coefficient (P). A detailed optimization of the drug release kinetics was presented by employing various kinetic models. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] MTT assay, a frequently used technique for assessing cytotoxicity in anticancer research, was used to gauge the effectiveness of these QCT-loaded mixed nanoaggregates.

Bacterial microcompartments as a next-generation metabolic engineering tool: utilizing nature's solution for confining challenging catabolic pathways.

Advancements in synthetic biology have facilitated the incorporation of heterologous metabolic pathways into various bacterial chassis, leading to the synthesis of targeted bioproducts. However, total output from heterologous production pathways can suffer from low flux, enzyme promiscuity, formation of toxic intermediates, or intermediate loss to competing reactions, which ultimately hinder their full potential. The self-assembling, easy-to-modify, protein-based bacterial microcompartments (BMCs) offer a sophisticated way to overcome these obstacles by acting as an autonomous catalytic module decoupled from the cell's regulatory and metabolic networks. More than a decade of fundamental research on various types of BMCs, particularly structural studies of shells and their self-assembly, the recruitment of enzymes to BMC shell scaffolds, and the involvement of ancillary proteins such as transporters, regulators, and activating enzymes in the integration of BMCs into the cell's metabolism, has significantly moved the field forward. These advances have enabled bioengineers to design synthetic multi-enzyme BMCs to promote ethanol or hydrogen production, increase cellular polyphosphate levels, and convert glycerol to propanediol or formate to pyruvate. These pioneering efforts demonstrate the enormous potential of synthetic BMCs to encapsulate non-native multi-enzyme biochemical pathways for the synthesis of high-value products.

New Insights on Solvent-Induced Changes in Refractivity and Specific Rotation of Poly(propylene oxide) Systems Extracted from Channeled Spectra.

Investigation of chiroptical polymers in the solution phase is paramount for designing supramolecular architectures for photonic or biomedical devices. This work is devoted to the case study of poly(propylene oxide) (PPO) optical activity in several solvents: benzonitrile, carbon disulfide, chloroform, ethyl acetate, and p-dioxane. To attain information on the interactions in these systems, rheological testing was undertaken, showing distinct variations of the rheological parameters as a function of the solvent type. These aspects are also reflected in the refractive index dispersive behavior, from which linear and non-linear optical properties are extracted. To determine the circular birefringence and specific rotation of the PPO solutions, the alternative method of the channeled spectra was employed. The spectral data were correlated with the molecular modeling of the PPO structural unit in the selected solvents. Density functional theory (DFT) computational data indicated that the torsional potential energy-related to the O1-C2-C3-O4 dihedral angle from the polymer repeating unit-was hindered in solvation environments characterized by high polarity and the ability to interact via hydrogen bonding. This was in agreement with the optical characterization of the samples, which indicated a lower circular birefringence and specific rotation for the solutions of PPO in ethyl acetate and p-dioxane. Also, the shape of optical rotatory dispersion curves was slightly modified for PPO in these solvents compared with the other ones.

Aqueous biphasic systems developed with deep eutectic solvents and polymer for the efficient extraction of pigments from beverages.

Novel aqueous biphasic systems (ABSs) developed with benzyl-based quaternary ammonium salts-deep eutectic solvents (DESs) and polypropylene glycol (PPG) were herein proposed. The liquid-liquid equilibrium and the partitioning behavior of pigments in the systems were addressed. The results suggested that the shorter the carbon chain length of the DES, the easier to form two phases. The analysis of mixed samples showed that the selective separation was achieved in the ABSs, including 99.47% of tartrazine in the DES-rich phase and 98.47% of sudan III in the PPG-rich phase. Additionally, the systems were successfully applied to the extraction of pigments from the actual beverage samples with recoveries ranging from 93.43% to 102.15%. Furthermore, the study on the separation mechanism indicated that the hydrogen bonding played a significant role in the separation process. All the above results highlight the proposed DES/polymer-based ABSs have great advantages in selective and high-performance separation of pigments from beverages.

Blood compatibility of poly(propylene glycol diester) and its water structure observed by differential scanning calorimetry and 2H-nuclear magnetic resonance spectroscopy.

Recently, we applied solution 2H-nuclear magnetic resonance spectroscopy (2H NMR) to analyze the water (deuterium oxide, D2O) structure in several biopolymers at ambient temperature. We established that polymers with good blood compatibility (i.e. poly(2-methoxyethyl acrylate) (PMEA)) have water observed at high magnetic fields (upfield) compared with bulk water. Polymers containing poly(propylene glycol) (PPG) or poly(propylene oxide) (PPO) exhibit good compatibility; however, the reason for this remains unclear. In addition, reports on the blood compatibility of PPO/PPG are limited. Therefore, PPG diester (PPGest) was prepared as a model polymer, and its blood compatibility and water structure were investigated. PPGest exhibited excellent blood compatibility. The water in PPGest was observed upfield by 2H NMR, and it was defined as non-freezing water via differential scanning calorimetry. Based on these observations, the relationship between the blood compatibility and water structure of PPGest is discussed by comparing with those of PMEA, and the reason for the good performance of PPG/PPO-based polymers is discussed.

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.

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, 17ß-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.

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.

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.

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.

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.

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 ß-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 ß-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.

Effects of propylene glycol used at different doses in Akkaraman lambs rations on metabolism-related parameters and liver gene and protein expression during different feeding periods.

This study aimed to investigate the metabolic effects of propylene glycol (PG) over 60, 90, and 120 days in lambs. Seventy-two weaned male lambs were allocated into three groups: control (Con), PG1.5 (1.5 mL/kg live weight0.75 ), and PG3 (3 mL/kg live weight0.75 ). Blood samples were collected at the beginning and slaughter days. Biochemical parameters (glucose, triglycerides, ALT, AST, LDH, BUN, and insulin) and gene and protein levels of peroxisome proliferator activated receptor gamma (PPARγ), diacylglycerol o-acyltransferase 1 (DGAT1), carbohydrate responsive element binding protein (ChREBP), and sterol regulatory element binding transcription factor 1c (SREBP-1c) in the liver were determined. Glucose in PG1.5 was increased on Day 60, while significant differences were observed in biochemical parameters except for insulin on the 60, 90, and 120 days. Biochemical parameters such as ALT, AST, LDH, and BUN increased over time, while triglycerides decreased. DGAT1 gene and protein levels were lower, while SREBP-1c and PPARγ were higher in PG groups on Day 60. While SREBP-1c was lower in PG1.5, ChREBP was higher in PG3 on Day 90. PPARγ, DGAT1, and ChREBP were upregulated in PG3 on Day 120. Positive correlations were found between proteins. The long-term use of PG in lambs did not have detrimental effects on metabolism. The study provides valuable insights into the molecular mechanisms underlying the metabolic effects of PG in lambs, shedding light on its potential applications in lamb production.

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-3ß-ol (4), 5,6-Epoxystigmasta-3ß,22,23-triol (5), Stigmastane-3ß,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-3ß,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-3ß-ol (4) and stigmast-5-ene-3ß,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-3ß,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.

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.

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.

Effects of daily propylene glycol drenching during the Ovsynch protocol on fertility and metabolic parameters in lactating dairy cows.

Negative energy balance (NEB) caused by restricted feed intake leads to body condition loss (BCS), increased metabolic stress and reduced fertility in dairy cows. Propylene glycol (PG) is a precursor of ruminal propionate for gluconeogenesis used to increase metabolic adaptation to the early postpartum period. The aim of this study was to determine the effects of daily drenching of PG during the fixed-time artificial insemination (FTAI) protocol on beta-hydroxybutyric acid (BHBA), glucose, adiponectin, insulin-like growth factor-1 (IGF1) concentrations, follicle size and pregnancy rate in dairy cows. Cows (n = 148) were randomly divided into two groups and received either 300 mL of PG (PG-OVS, n = 76) or 300 mL of water (CON-OVS, n = 72) each day of the Ovsynch protocol (GnRH-7 days-PGF2α -56 hours-GnRH-16-18-hour FTAI) between days 57 ± 3 to 67 ± 3 postpartum for the first service. Body condition scores (14 days before expected calving, at calving, on days 21 and 42 postpartum) were recorded. Blood samples were collected days 7 ± 3, 21 ± 3 postpartum, at the beginning of the Ovsynch (days 57 ± 3) and at the time of FTAI (days 67 ± 3) for measurements of BHBA, glucose, adiponectin and IGF1 concentrations. Ultrasonographic examinations were done to measure follicle size at the beginning of Ovsynch and FTAI and to determine pregnancy on days 30 and 60 following FTAI. There were no differences (p > .05) in glucose, adiponectin and IGF1 concentrations between the groups during the study. Although there was no difference (p > .05) in BHBA concentrations on postpartum day 7 ± 3, 21 ± 3 and 57 ± 3 between the groups, BHBA concentrations at the time of insemination was lower (p < .05) in the PG-OVS group (0.72 ± 0.03 mmol/L) than in the CON-OVS group (0.81 ± 0.03 mmol/L). Follicle sizes at the beginning of Ovsynch (PG-OVS, 14.5 ± 0.48 mm; CON-OVS, 14.3 ± 0.59 mm) and FTAI (PG-OVS, 17.8 ± 0.52 mm; CON-OVS, 17.7 ± 0.42 mm) were not different (p < .05). Pregnancy rate of the cows in the PG-OVS group (46.1%, 35/76) was higher (p = .05) than in the CON-OVS group (30.6%, 22/72) on day 30 following FTAI. In conclusion, decreasing serum BHBA concentrations at the time of FTAI by means of daily drenching of PG during the Ovsynch protocol, increased the pregnancy rate at first service in lactating dairy cows. On the other hand, blood glucose was not related with pregnancy rates in our study, probably as a result of our sampling time and more rapid fluctuations of blood glucose concentrations when compared to BHBA.