Global prevalence of resilience in health care professionals: A systematic review, meta-analysis and meta-regression.

AIMS: This review aims to examine the prevalence estimate of low resilience among health care professionals and identify the factors affecting the prevalence. BACKGROUND: Health care professionals experience high levels of stress. Understanding the health care professionals' resilience may provide an insight into how they perform in a highly stressed environment. EVALUATION: A comprehensive search of 11 databases was conducted. Studies that provided prevalence rates for low resilience among health care professionals working in a health care setting were included. Meta-analyses, sensitivity, subgroup analyses and meta-regression were conducted. KEY ISSUES: Among 27,720 studies, 41 studies (N = 17,073) across 16 countries were included. The prevalence of low resilience was 26% (95% CI: 20-32). Subgroup analyses indicated that types of resilience measures affect resilience prevalence significantly. A higher prevalence of low resilience was observed among allied health professions during the COVID-19 pandemic in the Middle East. CONCLUSIONS: This review indicated the prevalence of low resilience and type of resilience measurement instruments that affected the prevalence. IMPLICATIONS FOR NURSING MANAGEMENT: This review provides a roadmap to design tailored, discipline-specific and sustainable resilience training for nurses. Nursing managers should monitor the working hours and workload of nursing staffing in order to provide a protective working environment. This is a systematic review, and the PROSPERO registration number is CRD42021235350.

Imaging methods for determining uptake and toxicity of carbon nanotubes in vitro and in vivo.

Demand for carbon nanotubes (CNTs) is increasing rapidly in electrical, mechanical, and health and medical applications due to their thermal, electrical conductive and other properties. The continued commercial up-scaling of CNT production and application needs to be accompanied by an understanding of the occupational health, public safety and environmental implications of these materials. An increasing volume of literature on the toxicity of CNTs is being published; however, the results of these studies are frequently inconclusive. Due to the enormous number of permutations of nanoparticle shape, dimensions, composition and surface chemistry, only a fundamental understanding of the processes by which CNTs interact with cells will allow a realistic, practical assessment of the risks of the wide range of possible products. Alternatively, by understanding how the physicochemical properties of CNTs relate to their interaction with cells, it will be possible to design 'medical grade' CNTs, which can be used as diagnostic agents or as vectors to deliver therapeutic agents to cell and tissue targets. This article discusses the challenges associated with characterizing the toxicity of CNTs and the need for complimentary nanometrology techniques to relate their physicochemical properties to their toxicity.

Toxicity and imaging of multi-walled carbon nanotubes in human macrophage cells.

Multi-walled carbon nanotubes (MWNTs) have been proposed for use in many applications and concerns about their potential effect on human health have led to the interest in understanding the interactions between MWNTs and human cells. One important technique is the visualisation of the intracellular distribution of MWNTs. We exposed human macrophage cells to unpurified MWNTs and found that a decrease in cell viability was correlated with uptake of MWNTs due to mainly necrosis. Cells treated with purified MWNTs and the main contaminant Fe(2)O(3) itself yielded toxicity only from the nanotubes and not from the Fe(2)O(3). We used 3-D dark-field scanning transmission electron microscopy (DF-STEM) tomography of freeze-dried whole cells as well as confocal and scanning electron microscopy (SEM) to image the cellular uptake and distribution of unpurified MWNTs. We observed that unpurified MWNTs entered the cell both actively and passively frequently inserting through the plasma membrane into the cytoplasm and the nucleus. These suggest that MWNTs may cause incomplete phagocytosis or mechanically pierce through the plasma membrane and result in oxidative stress and cell death.

Phytochemical profiling and phase II enzyme-inducing properties of Thunbergia laurifolia Lindl. (RC) extracts.

Thunbergia laurifolia Lindl. (Acanthaceae) or Rang Chuet (RC) is described in traditional medicine for protection against dietary and environmental toxicants. This work, therefore, investigated RC's phytochemical profile, antimutagenic activity, and xenobiotic detoxification potential in its extracts. RC extracts were prepared by infusion with water, ethanol, acetone and subsequently assayed for major phytochemical constituents. Total phenolic content was 24.33, 5.65, and 1.42microg gallic acid equivalent (GAE) per mL for water, ethanol and acetone extract, respectively. HPLC analysis identified caffeic acid and apigenin as primary constituents of water extracts. Acetone and ethanol extracts contained primarily chlorophyll a and b, pheophorbide a, pheophytin a, and lutein. Treatment of Hepa 1C1C7 cells with standardized RC extracts resulted in a dose-dependent increase in QR specific activity for all extracts. Acetone extract (92microg GAE/mL) increased QR activity 2.8-fold, while ethanol (120microg GAE/mL) and water (1000microg GAE/mL) extracts increased QR activity by 1.35- and 1.56-fold, respectively. The RC extracts were subsequently assayed for mutagen and antimutagenic activity by bacterial reverse mutagenesis assay. All three RC extracts exhibited strong dose-dependent antimutagenic activity inhibiting 2-aminoanthracene induced mutagenesis up to 87% in Salmonella typhimurium TA 98. These results support the traditional medicinal use of RC for detoxification and suggest the potential role of both phenolic acids and natural chlorophyll constituents in modulating these effects.

Biphasic modulation of vascular nitric oxide catabolism by oxygen.

Endothelium-derived nitric oxide (NO) plays an important role in the regulation of vascular tone. Lack of NO bioavailability can result in cardiovascular disease. NO bioavailability is determined by its rates of generation and catabolism; however, it is not known how the NO catabolism rate is regulated in the vascular wall under normoxic, hypoxic, and anaerobic conditions. To investigate NO catabolism under different oxygen concentrations, studies of NO and O2 consumption by the isolated rat aorta were performed using electrochemical sensors. Under normoxic conditions, the rate of NO consumption in solution was enhanced in the presence of the rat aorta. Under hypoxic conditions, NO consumption decreased in parallel with the O2 concentration. Like the inhibition of mitochondrial respiration by NO, the inhibitory effects of NO on aortic O2 consumption increased as O2 concentration decreased. Under anaerobic conditions, however, a paradoxical reacceleration of NO consumption occurred. This increased anaerobic NO consumption was inhibited by the cytochrome c oxidase inhibitor NaCN but not by the free iron chelator deferoxamine, the flavoprotein inhibitor diphenylene iodonium (10 microM), or superoxide dismutase (200 U/ml). The effect of O2 on the NO consumption could be reproduced by purified cytochrome c oxidase (CcO), implying that CcO is involved in aortic NO catabolism. This reduced NO catabolism at low O2 tensions supports the maintenance of effective NO levels in the vascular wall, reducing the resistance of blood vessels. The increased anaerobic NO catabolism may be important for removing excess NO accumulation in ischemic tissues.