287 research outputs found
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Monitoring of carbon dioxide uptake in accelerated carbonation processes applied to air pollution control residues
The application of Accelerated Carbonation Technology (ACT) has potential for the sequestration of carbon in waste and geological materials. ACT also has potential to be supported by carbon credit mechanisms based upon the amount of carbon sequestered from industrial emissions. For this to happen, the routine monitoring of CO2 sequestered into the solid phase is required for the planning and operation of any accelerated carbonation plant. The present paper reports the preliminary results from an assessment of existing methods for measuring CO2 imbibed into a solid by an accelerated carbonation processes. Laboratory-scale experiments were carried out to evaluate the accuracy of methodologies for measuring mineralised carbon including: loss on ignition, acid digestion and total carbon analysis. The CO2 reactivity of several wastes from municipal incineration known as Air Pollution Control residues (APCr) were also included in the study. A detailed characterisation of the materials being carbonated, using X-ray diffraction (XRD), X-ray fluorescence (XRF), thermogravimetric analysis (TGA) and ion chromatography was carried out. The results of this study showed that monitoring CO2 during accelerated carbonation is made difficult by the complex mineralogy of materials such as APCrs. As such, the presence of calcium bearing species and polymorphs of calcium carbonate formed varied between the materials investigated. The use of an acid digestion technique was not subject to interference from the chemistry or mineralogy of an ash. Among the investigated methods, acid digestion gives the most promising results as it provided robust data on the amount of carbon imbibed during processing
Parkinson's disease: autoimmunity and neuroinflammation
Parkinson's disease is a neurodegenerative disease that causes the death of dopaminergic neurons in the substantia nigra. The resulting dopamine deficiency in the basal ganglia leads to a movement disorder that is characterized by classical parkinsonian motor symptoms. Parkinson's disease is recognized as the most common neurodegenerative disorder after Alzheimer's disease.
PD ethiopathogenesis remains to be elucidated and has been connected to genetic, environmental and immunologic conditions.
The past decade has provided evidence for a significant role of the immune system in PD pathogenesis, either through inflammation or an autoimmune response. Several autoantibodies directed at antigens associated with PD pathogenesis have been identified in PD patients. This immune activation may be the cause of, rather than a response to, the observed neuronal loss.
Parkinsonian motor symptoms include bradykinesia, muscular rigidity and resting tremor. The non-motor features include olfactory dysfunction, cognitive impairment, psychiatric symptoms and autonomic dysfunction.
Microscopically, the specific degeneration of dopaminergic neurons in the substantia nigra and the presence of Lewy bodies, which are brain deposits containing a substantial amount of α-synuclein, have been recognized.
The progression of Parkinson's disease is characterized by a worsening of motor features; however, as the disease progresses, there is an emergence of complications related to long-term symptomatic treatment.
The available therapies for Parkinson's disease only treat the symptoms of the disease. A major goal of Parkinson's disease research is the development of disease-modifying drugs that slow or stop the neurodegenerative process. Drugs that enhance the intracerebral dopamine concentrations or stimulate dopamine receptors remain the mainstay treatment for motor symptoms.
Immunomodulatory therapeutic strategies aiming to attenuate PD neurodegeneration have become an attractive option and warrant further investigation
An unusual presentation of anomalous left coronary artery from the pulmonary artery (ALCAPA) syndrome in a 70-year-old man: a case report
Background: We present a rare case of anomalous origin of the left coronary artery from the pulmonary artery
syndrome in an elderly man, and we describe coronary computed tomographic angiographic imaging findings to
improve diagnostic confidence for the evaluation of this uncommon coronary artery anomaly.
Case presentation: A 70-year-old Caucasian man came to our hospital with slight limitation of physical activity
(New York Heart Association class II). He was asymptomatic for angina, syncope, and palpitations. Cardiac magnetic
resonance imaging was performed after echocardiography because a hypertrophic cardiomyopathy was suspected;
a plausible coronary artery anomaly was demonstrated as collateral evidence. Subsequently, coronary computed
tomographic angiography showed the anomalous origin of left coronary artery from the pulmonary artery; the
coronary vessels appeared markedly dilated and tortuous. Dilated intercoronary vessels along the epicardial surface
of the heart and dilated bronchial arteries, corresponding to collateral pathways, were observed. Left ventricular
hypertrophy, delayed subendocardial enhancement, and mitral insufficiency were better evaluated on
magnetic resonance images. Invasive coronary angiography confirmed the main findings. Given the patientâs
age and clinical performance, surveillance with medical management was considered appropriate, and surgical repair
was avoided.
Conclusions: Confidence with the anatomic pattern and clinical significance of this anomalous condition is necessary
to improve cardiac imaging evaluation ability. In our patient, coronary computed tomographic angiography proved to
be a reliable imaging approach, superior to invasive coronary angiography in terms of diagnostic performance and
patient safety
Iron (II) citrate complex as a food supplement: Synthesis, characterization and complex stability
Iron deficiency represents a widespread problem for a large part of the population, especially for women, and has received increasing attention in food/supplement research. The contraindications of the iron supplements commercially available (e.g., imbalances in the levels of other essential nutrients, low bioavailability, etc.) led us to search for a possible alternative. In the present work, a rapid and easy method to synthetize a solid iron (II) citrate complex from iron filings and citric acid was developed to serve, eventually, as a food supplement or additive. In order to state its atomic composition and purity, an assortment of analytical techniques was employed (e.g., combustion analysis, thermogravimetry, X-ray diffractometry, UV/Vis spectrophotometry, etc.). Results demonstrate that the synthesized crystalline solid corresponds to the formula FeC6H6O7âH2O and, by consequence, contains exclusively iron (II), which is an advantage with respect to existing commercial products, because iron (II) is better absorbed than iron (III) (high bioavailability of iron)
Potential Therapeutic Effects of Vitamin E and C on Placental Oxidative Stress Induced by Nicotine: An In Vitro Evidence
There have been a few studies that examined the oxidative stress effects of nicotine during pregnancy and lactation. The adverse effect of prenatal smoking exposure on human fetal development and growth has been a major public health issue. Active or passive smoking during pregnancy can result in a wide variety of adverse outcomes, including intrauterine growth retardation (IUGR), prematurity, stillbirth, and the sudden infant death syndrome. Smoking in pregnancy has also been associated with an increased risk of attention deficit and learning problems in childhood. Some studies argued that as a principal component of tobacco smoke, nicotine alone is responsible for the majority of negative reproductive outcomes. Nicotine and its major metabolite cotinine can cross the placental barrier. The level of nicotine in fetal tissues was found to be equal to or greater than the plasma nicotine level in the mothers. The oxidative stress induce by nicotine has been increasingly postulated as a major contributor to endothelial dysfunction. A large body of research has investigated the potential role of antioxidant nutrients in the prevention of endothelial dysfunction in women. Therefore, the present study was undertaken to assess the potential benefit of antioxidant supplementation on markers of placental oxidative stress in an in vitro model of endothelial dysfunction induced by nicotine, since it was previously found that nicotine is able to trigger the placental secretion of stress molecules. In this regard, we evaluated the effects of vitamin C, vitamin E and N-acetylcysteine (NAC), alone or in combination, in placental villi culture after exposure to nicotine. The effect of antioxidant nutrients on trophoblast cells proliferation and vitality was also evaluated. The results obtained suggest that in a patho-physiological condition, such as endothelial dysfunction induced by nicotine, the deleterious effect of reactive oxygen species may be counteracted by an antioxidant therapy, and there is the need to investigate the optimum dosing and timing of antioxidants administration, since an inappropriate antioxidant treatment in pregnant women may have deleterious consequences, reducing placental cells proliferation until to cell death
Characterization of the most frequent ATP7B mutation causing Wilson disease in hepatocytes from patient induced pluripotent stem cells
H1069Q substitution represents the most frequent mutation of the copper transporter ATP7B causing Wilson disease in Caucasian population. ATP7B localizes to the Golgi complex in hepatocytes but moves in response to copper overload to the endo-lysosomal compartment to support copper excretion via bile canaliculi. In heterologous or hepatoma-derived cell lines, overexpressed ATP7B-H1069Q is strongly retained in the ER and fails to move to the post-Golgi sites, resulting in toxic copper accumulation. However, this pathogenic mechanism has never been tested in patients' hepatocytes, while animal models recapitulating this form of WD are still lacking. To reach this goal, we have reprogrammed skin fibroblasts of homozygous ATP7B-H1069Q patients into induced pluripotent stem cells and differentiated them into hepatocyte-like cells. Surprisingly, in HLCs we found one third of ATP7B-H1069Q localized in the Golgi complex and able to move to the endo-lysosomal compartment upon copper stimulation. However, despite normal mRNA levels, the expression of the mutant protein was only 20% compared to the control because of endoplasmic reticulum-associated degradation. These results pinpoint rapid degradation as the major cause for loss of ATP7B function in H1069Q patients, and thus as the primary target for designing therapeutic strategies to rescue ATP7B-H1069Q function
SARS-CoV-2 vaccines: What we know, what we can do to improve them and what we could learn from other well-known viruses
: In recent weeks, the rate of SARS-CoV-2 infections has been progressively increasing all over the globe, even in countries where vaccination programs have been strongly implemented. In these regions in 2021, a reduction in the number of hospitalizations and deaths compared to 2020 was observed. This decrease is certainly associated with the introduction of vaccination measures. The process of the development of effective vaccines represents an important challenge. Overall, the breakthrough infections occurring in vaccinated subjects are in most cases less severe than those observed in unvaccinated individuals. This review examines the factors affecting the immunogenicity of vaccines against SARS-CoV-2 and the possible role of nutrients in modulating the response of distinct immune cells to the vaccination
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