Personality and job satisfaction among Chinese health practitioners: The mediating role of professional quality of life

This study aims to explore mediating effects of professional quality of life on the relationship between big-five personality traits and job satisfaction in a Chinese healthcare setting. A total of 1620 Chinese healthcare professionals were recruited to participate in a randomised cross-sectional survey. The results suggest that professional quality of life transmitted the effect of personality to job satisfaction. Specifically, compassion satisfaction and burnout mediated the positive effect of extraversion, agreeableness, conscientiousness, and openness upon job satisfaction; as well as mediated negative effects of neuroticism upon job satisfaction. Secondary traumatic stress mediated the positive effect of extraversion upon job satisfaction. The paper also discusses the cultural factors contributing to the mediating effects and implications offered by the study at the macro, messo, and micro levels

Identification of a Novel Gene for Biosynthesis of a Bacteroid-Specific Electron Carrier Menaquinone

Ubiquinone (UQ) has been considered as an electron mediator in electron transfer that generates ATP in Rhizobium under both free-living and symbiosis conditions. When mutated, the dmtH gene has a symbiotic phenotype of forming ineffective nodules on Astragalus sinicus. The gene was isolated from a Mesorhizobium huakuii 7653R transposon-inserted mutant library. The DNA sequence and conserved protein domain analyses revealed that dmtH encodes demethylmenaquinone (DMK) methyltransferase, which catalyzes the terminal step of menaquinone (MK) biosynthesis. Comparative analysis indicated that dmtH homologs were present in only a few Rhizobia. Real-time quantitative PCR showed dmtH is a bacteroid-specific gene. The highest expression was seen at 25 days after inoculation of strain 7653R. Gene disruption and complementation tests demonstrated that the dmtH gene was essential for bacteroid development and symbiotic nitrogen fixation ability. MK and UQ were extracted from the wild type strain 7653R and mutant strain HK116. MK-7 was accumulated under microaerobic condition and UQ-10 was accumulated under aerobic condition in M. huakuii 7653R. The predicted function of DmtH protein was confirmed by the measurement of methyltransferase activity in vitro. These results revealed that MK-7 was used as an electron carrier instead of UQ in M. huakuii 7653R bacteroids

Unraveling the correlations between conformation, lubrication, and chemical stability of bottlebrush polymers at interfaces

In the present study, we monitored the conformation and chemical stability of a hydrophilic bottlebrush (BB) polymer in pure water and buffered saline solutions. We correlated these parameters to lubricating and wear protecting properties. Using the Surface Forces Apparatus (SFA), we show that the BB polymer partially adsorbs on mica surfaces and extends half its contour length toward the aqueous media. This conformation gives rise to a strong repulsive interaction force when surfaces bearing BB polymer chains are pressed against each other. Analysis of these repulsive forces demonstrated that the adsorbed polymer chains could be described as end-attached elastic rods. After 2 months of aging at temperatures ranging from 4 to 37 °C, partial scission of the BB polymer's lateral chains was observed by Gel Permeation Chromatography with a half-life time of the polymer of at least two years. The thickness of the BB polymer layer assessed by SFA appeared to quickly decrease with aging time and temperature which was mainly caused by the adsorption to the substrate of the released lateral chains. The gradual loss of the BB polymer lateral chains did not impact significantly the tribological properties of the BB polymer solution nor its wear protection capacity. The friction coefficient between mica surfaces immersed in the BB polymer solution was = 0.031 ± 0.002, and was independent of the aging conditions and remained constant up to an applied pressure P = 15 atm. Altogether, this study demonstrates that besides the gradual loss of lateral chains, the BB polymer is still able to perform adequately as a lubricant and wear protecting agent over a time period suitable for in vivo administration

Lubrication and wear protection of micro-structured hydrogels using bioinspired fluids

We report the fabrication and the use of a bioinspired synovial fluid acting as a lubricant fluid and anti-wear agent at soft and porous chitosan hydrogel tribopairs. This synthetic synovial fluid is composed of sodium hyaluronate (HA) and a bottle-brush polymer (BB) having a polycationic attachment group and polyzwitterionic pendant chains. 2.5 %w/w chitosan hydrogel plugs are organized in a bilayered structure exposing a thin and dense superficial zone (SZ), covering a porous deep zone (DZ) and exhibiting microchannels perpendicularly aligned to the SZ. Using a low-load tribometer, the addition of HA lubricating solution at the hydrogel-hydrogel rubbing contact drastically decreased the coefficient of friction (CoF) from μ = 0.20 ± 0.01 to μ = 0.04 ± 0.01 on the DZ configuration and from μ = 0.31 ± 0.01 to μ = 0.08 ± 0.01 on the SZ surface when increasing HA concentration from 0 to 1000 μg/mL and its molecular mass from 10 to 1500 kDa, similar to what was found when using BB polymer alone. When combining the BB polymer and the 1500 kDa HA, the CoF remained stable at μ = 0.04 ± 0.01 for both studied contact configurations, highlighting the synergistic interaction of the two macromolecules. Hydrogel wear was characterized by assessing the final gel surface roughness by the means of an interferometer. Increasing HA concentration and molecular weight plus the addition of BB polymer lead to a dramatic surface wear protection with a final gel surface roughness of the hydrogels similar to the untested gels. In brief, BB polymer in combination with high molecular weight HA is a potential lubricating fluid as well as a wear resistant agent for soft materials lubrication and wear protection

Wear protection without surface modification using a synergistic mixture of molecular brushes and linear polymers

We describe the design of lubricating and wear protecting fluids based on mixtures of bottlebrushes (BB) and linear polymers solutions. To illustrate this concept we used hyaluronic acid (HA) - a naturally occurring linear polyelectrolyte, and a water soluble synthetic BB polymer. Individually, these two polymers exhibit poor wear protecting capabilities compared to saline solutions. Mixture of the two polymers in pure water or in saline allows to drastically increase wear protection of surfaces over a wide range of shearing conditions. We demonstrate that this synergy between the BB and HA polymers emerges from a strong cohesion between the two components forming the boundary film due to entanglements between both polymers. We show that this concept can be applied to other types of linear polymers and surfaces and is independent of the chemical and mechanical properties of the surfaces

Study on the accessibility and affordability of 50 drugs in Wuhan based on the WHO/HAI standardization method

ObjectiveTo understand the availability and affordability of essential drugs in Wuhan since the implementation of the national essential medicine system, and to provide a basis for the subsequent formulation and improvement of related policies.MethodsUsing the standard survey method jointly developed by the WHO and Health Action International (HAI), a sample of 50 essential drugs was selected to investigate and evaluate their availability and affordability in public medical and health institutions and social retail pharmacies in Wuhan, using six diseases with high clinical morbidity as the targets.ResultsThe availability of the original drug and the lowest-priced generic drug in public hospitals is 26.4 and 42.47% respectively, and that in retail pharmacies is 26.8 and 54.4% respectively. The median price ratio of the original drug and the lowest-priced generic drug is 28.71 and 2.23 respectively in public hospitals, and 29.24 and 3.59 respectively in retail pharmacies; In addition to individual drugs, such as omeprazole, others are affordable. The availability of essential drugs in public hospitals in Wuhan is lower than that in social retail pharmacies, and the availability of the lowest-priced generic drugs is much higher than that of original drugs.ConclusionThe availability of essential drugs in public hospitals in Wuhan is lower than that in social retail pharmacies, and the availability of the lowest-priced generic drugs is much higher than that of original drugs. The price of the original drug is much higher than the international reference price; The price of medicines in public hospitals is lower than that in retail pharmacies;the overall condition of affordability is good, but there is a big gap between the affordability levels of original drugs and generic drugs, and the affordability of original drugs is relatively poor. It is recommended to adjust the relevant policies according to the actual situation of Wuhan city itself, moderately ensure the supply of original drugs, improve the price transparency of retail pharmacies, and ensure that the basic drug needs of the public are met

Intermolecular interactions between Bottlebrush Polymers boost the protection of surfaces against frictional wear

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in Chemistry of materials, copyright American Chemical Society after peer review and technical editing by the publisher."Polymers exhibiting the bottlebrush (BB) architecture have excellent lubricating properties. However, to motivate their use in real life systems, they must also protect surfaces against frictional damage. In this article, we synthesized a library of polyzwiterrionic bottlebrush polymers of different architectures to explore the effect of intermolecular interactions on their conformation at interfaces and their tribological properties. Using the surface forces apparatus, we show that increasing the number of adhesive blocks on the BB polymers does not impact the friction coefficient on mica surfaces, μ, which remained close to μ = 0.02 but drastically increased the threshold pressure, P*, at which wear initiates from P* = 0.4 ± 0.1 up to 8.0 ± 0.8 MPa. In mixtures of high molecular weight hyaluronic acid and BB polymers, a synergistic interaction between polymers occurred, leading to a significant increase in P*, independently of the BB polymer tested and even reaching superprotection for strongly interacting polymers (up to P* > 14 MPa). Overall, these results show that strong intermolecular interaction between BB polymers and high molecular weight linear polymers is a promising strategy to create highly protective lubricants

Deep tissue penetration of bottle-brush polymers via cell capture evasion and fast diffusion

Drug nanocarriers (NCs) capable of crossing the vascular endothelium and deeply penetrating into dense tissues of the CNS could potentially transform the management of neurological diseases. In the present study, we investigated the interaction of bottle-brush (BB) polymers with different biological barriers in vitro and in vivo and compared it to nanospheres of similar composition. In vitro internalization and permeability assays revealed that BB polymers are not internalized by brain-associated cell lines and translocate much faster across a blood–brain barrier model compared to nanospheres of similar hydrodynamic diameter. These observations performed under static, no-flow conditions were complemented by dynamic assays performed in microvessel arrays on chip and confirmed that BB polymers can escape the vasculature compartment via a paracellular route. BB polymers injected in mice and zebrafish larvae exhibit higher penetration in brain tissues and faster extravasation of microvessels located in the brain compared to nanospheres of similar sizes. The superior diffusivity of BBs in extracellular matrix-like gels combined with their ability to efficiently cross endothelial barriers via a paracellular route position them as promising drug carriers to translocate across the blood–brain barrier and penetrate dense tissue such as the brain, two unmet challenges and ultimate frontiers in nanomedicine