Photosensitive Manifestations of HIV Disease
Clay J. Cockerell, Antoanella Calame in Cutaneous Manifestations of HIV Disease, 2012
HIV-infected patients have decreased levels of some major components of these antioxidant systems, notably potent endogenous thiol-reducing agents such as glutathione (GSH) and thioredoxin, involved in scavenger systems for electrophiles and ROS, as well as key enzymes such as catalase and superoxide dismutase. This may be due to an exhaustion of these scavengers caused by the overall increased state of oxidative stress. However, several other factors could be contributing to this depletion. Alterations in bowel mucosa reduce the host’s ability to absorb certain nutrients that play a direct role as free radical scavengers or key metabolites in their pathways, such as vitamins, flavonoids, quinones, minerals, and sulfur-containing amino acids.6 As the liver is a major source of scavengers like GSH,7 liver damage secondary to drugs and hepatotoxic viruses common in HIV disease may also limit production of these scavengers. Decreased levels of cystathionase, an enzyme necessary for GSH synthesis, and increased glutamate, which prevents intracellular transport of necessary substrates such as cysteine, further impede the patient’s ability to replenish these defenses. In addition, the HIV-1 tat protein represses superoxide dismutase, depriving the body of yet another defense against free radical damage.6
Real food economics
Pamela Mason, Tim Lang in Sustainable Diets, 2017
The cost of food waste is enormous. In preparation for the Second International Conference on Nutrition in 2014, the FAO published a summary of what this is. It calculated that food produce that is not consumed has an annual ‘bulk-trade value’ of $964 bn annually. This is a huge sum but, just as significant in the FAO’s view, is that these separate costs have knock-on or interactive effects. Lost food has also lost soil nutrients, which adds to soil depletion, which increases the likelihood of conflict from resource scarcity. Some FAO calculations are given in Table 7.1. Country case studies by the FAO show how significant this can be. One of milk wastage in Kenya, for example, calculated the actual loss of milk sales as 571,418 tonnes valued at US$151 m. But if the social and environmental costs due to GHGs, water, land, water pollution, soil erosion, water scarcity, biodiversity and human health were computed as well, this total loss rose to US$758 m.
Global environmental change and health
Kevin McCracken, David R. Phillips in Global Health, 2017
Land degradation, the decline in land quality, is a serious problem in all regions around the world and one of the major environmental threats to both current and future global population health. More than half of the world's land used for agriculture is now moderately to severely degraded, with around 2 billion hectares of land for crop production lost every year (UNCCD, 2011). Degradation takes many forms – loss of soil stabilizing vegetative cover, soil compaction, erosion, pollution, salinization, acidification, leaching and nutrient depletion, damaging siltation and pollution of inland waters, contamination of groundwater, desertification, etc. Natural forces can play a part, for example droughts, wildfires and coastal zone storm surges, but human factors are the main determinants. In essence, land degradation reflects a mismatch between land use and land quality. In the developing world, this mismatch is often driven by growing population pressures and widespread poverty, leading to overuse of farmlands and inappropriate expansion into ecologically fragile areas. In the more developed countries poor land use practices are also found, but they are driven more by desired market returns than the food-survival imperative facing many people in poorer countries (see also ‘Soil pollution’, below).
Caplacizumab: a change in the paradigm of thrombotic thrombocytopenic purpura treatment
Published in Expert Opinion on Biological Therapy, 2019
Maëlle le Besnerais, Agnès Veyradier, Ygal Benhamou, Paul Coppo
A better knowledge of the mechanisms involved in TTP has been rapidly and successfully translated into the clinic for the benefit of patients, making TTP an archetypal disease that has benefited from targeted therapies. After decades of empirical treatment with TPE, the identification of ADAMTS13 and the understanding of the mechanisms leading to its deficiency provided an explanation for the efficacy of plasma administration, and paved the way for the development of a recombinant form of the enzyme. Similarly, the demonstration of a major role of anti-ADAMTS13 antibodies spurred development of immunomodulatory strategies based on B-cell depletion. More recently, the inhibition of the platelet–vWF interaction by caplacizumab demonstrated efficacy in clinical trials through prevention of formation of further microthrombi and protection of organs from ischemia until immunosuppression is efficient [3,19].
Self-Stigma of seeking help and job burnout in mental health care providers: the comparative study of Lithuanian and the USA samples
Published in Journal of Workplace Behavioral Health, 2019
Auksė Endriulaitienė, Kristina Žardeckaitė-Matulaitienė, Aistė Pranckevičienė, Rasa Markšaitytė, Douglas R. Tillman, David D. Hof
Burnout might be defined as a state of physical, emotional, and mental exhaustion, resulting from frustrating work conditions and is comprised of three components: emotional exhaustion, depersonalization, and reduced personal accomplishment (Fradelos et al., 2014; Maslach, Schaufeli, & Leiter, 2001). Emotional exhaustion is a state of depletion; depersonalization is referred to as cynicism and detachment from personal interactions, and dehumanization of clients and coworkers; and reduced personal accomplishment is a feeling of low self-efficacy and ineffectiveness (Gregory & Menser, 2015; Maslach et al., 2001). These feelings distract the care provider from effective health-promoting ways of working and increase the likelihood of adverse mental or physical symptoms. Studies have consistently documented the deteriorating consequences of burnout, like poor quality of care, high absenteeism, low job satisfaction, low well-being, and poor mental and physical health of the mental health care providers (Bria, Baban, & Dumitrascu, 2012; Canadas-De la Fuente et al., 2015; Dreison et al., 2018; Fradelos et al., 2014; Lampert & Glaser, 2018; Luther et al., 2017; Ramberg & Wasserman, 2000; Siebert, 2004).
A critical review of the kinetic direct peptide reactivity assay (kDPRA) for skin sensitizer potency assessment – taking it forward
Published in Critical Reviews in Toxicology, 2021
From the 24 h depletion value observed in the DPRA with purified Azurone at 5 mM, the rate constant for peptide depletion by Azurone per se can be estimated as 3.2 × 10−4 l mol−1 s−1. Using this rate constant value, and assuming that the isoamyl catechol impurity has reacted completely within the first time interval (30 min), it is straightforward to calculate the shapes of the plots of ln(100-DP) versus [E] that would be obtained for Azurone (containing 2.5% impurity) by the kDPRA protocol.1Figure 2 shows the plot that would be obtained for the t = 210 min. data; the plots for the other t values are very similar and almost indistinguishable to the naked eye. This is because the depletion values are mainly due to the fast-reacting impurity with only a relatively small contribution from the main component. All of these plots would be expected to pass the linearity test, and by the kDPRA protocol the slope of the 30 min plot would be used to give the kmax value as shown in Table 2. At this point, it may be noted that although Azurone and Calone show some reactivity due to the main component, this may indicate peptide oxidation rather than adduct formation. Azurone and Calone have a Schiff base electrophile alert (ketone with electronegative substituents), and Schiff base electrophiles have been found to promote oxidation, but not to form stable adducts, in the DPRA (Natsch and Gfeller 2008).
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