Mortality and cardiovascular disease in patients with adrenal insufficiency

Increased risks for mortality and cardiovascular disease in primary and secondary adrenal insufficiency, and pituitary disorders have been inconsistently reported. Risk estimations have traditionally used national statistics as reference, with no matching for precise age, and time and place of clinical care of the patients and the reference population. This study evaluated risks for mortality and cardiovascular disease in patients with adrenal insufficiency of any type and, separately, primary and secondary adrenal insufficiency, by comparing with controls individually matched for sex, age, and time and place of care, using as the source of data a UK primary care database (Clinical Practice Research Datalink, CPRD). Additionally, established cardiovascular risk factors were taken into account. The risk for mortality was increased in patients with adrenal insufficiency (HR, 1.68 [95% CI, 1.58-1.77]) including primary (HR, 1.83 [1.66-2.02]) and secondary adrenal insufficiency (HR, 1.52 [1.40-1.64]). From the first year, the mortality risk was significantly increased, in accordance with an early increase in hospitalisations from adrenal crisis. Cardiovascular disease was the leading cause of death but infections posed the greatest relative mortality risk. Risk for cardiovascular events was increased but was dependent on the presence of cardiovascular risk factors (unadjusted HR, 1.28 [1.20-1.36]; adjusted HR, 1.07 [1.01-1.14]). However, specifically for cerebrovascular disease in secondary adrenal insufficiency, risk was independently increased. Concomitant cardiovascular disease was associated with adrenal crisis-related death. In conclusion, infections and adrenal crisis could account for the increased risk for mortality in adrenal insufficiency observed at the beginning of disease course. The risk for cardiovascular disease was also increased and could further contribute to adrenal crisis-related mortality. The interaction of the three factors: adrenal crisis, infections and cardiovascular disease, probably plays a part in the increased mortality of patients with adrenal insufficiency.Open Acces

Hypoglycaemia disappeared after transarterial chemoembolization in hepatocellular carcinoma

Non-Islet Cell tumour hypoglycaemia associated with hepatocellular carcinoma is an infrequent finding in clinical practice and provides a worse prognosis. The causes of hypoglycaemia are tumour production of insulin-like growth factor II and tumour uptake of glucose. There are many treatment options to control hypoglycaemia and some are unsuccessful. We thereby report a case of hepatocellular carcinoma, in which hypoglycaemia was successfully controlled by a first episode of transarterial chemoembolization

Review of Non-Thermal Plasma Technology for Hydrogenation of Vegetable Oils and Biodiesel

The hydrogenation of lipid derivative compounds has received much attention as it is one of the key chemical reactions of industrial processes to improve the physical and chemical properties of those compounds such as thermal resistance, cold flow properties, oxidative stability, etc. The principle of hydrogenation of vegetable oil for margarine production relies on the addition of hydrogen to the carbon double bond positions of fatty acid molecules to become a single bond, increasing the saturated fatty acids until the texture becomes semi-solid. The partial addition of hydrogen to biodiesel improves its oxidation resistance. At present, industrial-scale using catalytic hydrogenation of lipid derivative compounds operates under high temperature and high-pressure environments, leading to a high trans-fat content in the products and requiring catalyst separation from the product. Non-thermal plasma (NTP) technology as a green process can be deployed to substitute conventional hydrogenation, on a laboratory scale for the time being, because no catalyst is required and the process can occur at near ambient temperature and low or atmospheric pressure. Moreover, trans-fat formation is several times lower than that of catalytic hydrogenation. The present review article provides more insight into the various types of NTP technology for lipid derivative compounds hydrogenation, including discussions on different experimental setup configurations, parameters affecting plasma hydrogenation, properties of synthesized products, as well as the advantages and drawbacks of environmentally-friendly plasma hydrogenation compared to conventional catalytic hydrogenation

Influence of alkyl chain length on sulfated zirconia catalysed batch and continuous esterification of carboxylic acids by light alcohols

The impact of alkyl chain length on the esterification of C2–C16 organic acids with C1–C4 alcohols has been systematically investigated over bulk and SBA-15 supported sulfated zirconias (SZs). Rates of catalytic esterification for methanol with acetic acid are directly proportional to the sulfur content for both SZ and SZ/SBA-15, with the high dispersion of SZ achievable in conformal coatings over mesoporous SBA-15 confering significant rate-enhancements. Esterification over the most active 0.24 mmol gcat−1 bulk SZ and 0.29 mmol gcat−1 SZ/SBA-15 materials was inversely proportional to the alkyl chain length of alcohol and acid reactants; being most sensitive to changes from methanol to ethanol and acetic to hexanoic acids respectively. Kinetic analyses reveal that these alkyl chain dependencies are in excellent accord with the Taft relationship for polar and steric effects in aliphatic systems and the enthalpy of alcohol adsorption, implicating a Langmuir–Hinshelwood mechanism. The first continuous production of methyl propionate over a SZ fixed-bed is also demonstrated

Kinetics of extraction and in situ transesterification of oils from spent coffee grounds

Resource limits, environmental concerns and unstable petroleum costs have led to an increased effort to develop alternative liquid fuels. Purpose grown feedstocks are expensive and demand additional resources such as land and water. Spent coffee grounds (SCGs) are a good potential low-cost feedstock, however, processing times and costs must be lowered in order to be cost competitive with fossil fuels. In this work, we investigated the kinetics of oil extraction from SCGs to explore if current methods of oil extraction could be hastened and if an integrated process which couples oil extraction and conversion to biodiesel stages in one single step (in situ transesterification) was viable. Kinetics of oil extraction from SCGs using n-hexane as solvent was studied as a function of temperature, solvent to solid ratio and water content. We have found that oil extraction times could be as low as 10 min due to higher diffusion coefficients of oils from SCGs. Further, we demonstrate, for the first time, the successful in situ transesterification of SCGs using different concentrations of sodium hydroxide as a catalyst and methanol to oil mole ratios. Both of these outcomes show promise for lowering biodiesel production costs from SCGs, a ubiquitous waste product around the world

Process and Energy Intensification of Glycerol Carbonate Production from Glycerol and Dimethyl Carbonate in the Presence of Eggshell-Derived CaO Heterogeneous Catalyst

The process and energy intensifications for the synthesis of glycerol carbonate (GC) from glycerol and dimethyl carbonate (DMC) using an eggshell-derived CaO heterogeneous catalyst were investigated. The transesterification reaction between glycerol and DMC was typically limited by mass transfer because of the immiscible nature of the reactants. By varying the stirring speed, it was observed that the mass transfer limitation could be neglected at 800 rpm. The presence of the CaO solid catalyst made the mass transport-limited reaction process more prominent. Mass transfer intensification using a simple kitchen countertop blender as an alternative to overcome the external mass transfer limitation of a typical magnetic stirrer was demonstrated. A lower amount of the catalyst and a shorter reaction time were required to achieve 93% glycerol conversion or 91% GC yield, and the turnover frequency (TOF) increased almost 5 times from 1.5 to 7.2 min−1 when using a conventional magnetic stirrer and countertop blender, respectively. In addition, using a simple kitchen countertop blender with 7200 rpm, the reaction temperature of 60 °C could be reached within approximately 3 min without the need of a heating unit. This was the result of the self-frictional heat generated by the high-shear blender. This was considered to be heat transfer intensification, as heat was generated locally (in situ), offering a higher homogeneity distribution. Meanwhile, the trend toward energy intensification was promising as the yield efficiency increased from 0.064 to 2.391 g/kJ. A comparison among other process intensification techniques, e.g., microwave reactor, ultrasonic reactor, and reactive distillation was also rationalized

On the influence of Si:Al ratio and hierarchical porosity of FAU zeolites in solid acid catalysed esterification pretreatment of bio-oil

A family of faujasite (FAU) zeolites with different Si:Al ratio, and/or hierarchical porosity introduced via post-synthetic alkaline desilication treatment, have been evaluated as solid acid catalysts for esterification pretreatments of pyrolysis bio-oil components. Acetic acid esterification with aliphatic and aromatic alcohols including methanol, anisyl alcohol, benzyl alcohol, p-cresol and n-butanol was first selected as a model reaction to identify the optimum zeolite properties. Materials were fully characterised using N2 porosimetry, ICP, XRD, XPS, FT-IR, pyridine adsorption, NH3 TPD, In-situ ATR and inverse gas chromatography (IGC). IGC demonstrates that the surface polarity and hence hydrophobicity of FAU decreases with increased Si:Al ratio. Despite possessing a higher acid site loading and acetic acid adsorption capacity, high Al-content FAU possess weaker acidity than more siliceous catalysts. Esterification activity increases with acid strength and decreasing surface polarity following the order FAU30>FAU6>FAU2.6. The introduction of mesoporosity through synthesis of a hierarchical HFAU30 material further enhances esterification activity through improved acid site accessibility and hydrophobicity. Methanol was the most reactive alcohol for esterification, and evaluated with HFAU30 for the pretreatment of a real pyrolysis bio-oil, reducing the acid content by 76% under mild conditions

Kinetic modeling studies of heterogeneously catalyzed biodiesel synthesis reactions

The heterogeneously catalyzed transesterification reaction for the production of biodiesel from triglycerides was investigated for reaction mechanism and kinetic constants. Three elementary reaction mechanisms Eley-Rideal (ER), Langmuir-Hinshelwood-Hougen-Watson (LHHW), and Hattori with assumptions, such as quasi-steady-state conditions for the surface species and methanol adsorption, and surface reactions as the rate-determining steps were applied to predict the catalyst surface coverage and the bulk concentration using a multiscale simulation framework. The rate expression based on methanol adsorption as the rate limiting in LHHW elementary mechanism has been found to be statistically the most reliable representation of the experimental data using hydrotalcite catalyst with different formulations