Publications by authors named "Richard O Jenkins"

Albumin is a major protein in mammalian blood plasma or serum, where its concentration in healthy organisms is about 600 μM [...

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Data are accumulating on the hydrolytic activity of serum albumin towards esters and organophosphates. Previously, with the help of the technology of proton nuclear magnetic resonance (H NMR) spectroscopy, we observed the yield of acetate in the solution of bovine serum albumin and -nitrophenyl acetate (NPA). Thus, we showed that albumin possesses true esterase activity towards NPA.

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Article Synopsis
  • - The study investigates the effects of decaffeinated green tea extract (GTE) and two ammonium salts (ACL and ACR) on physical performance in a rat swimming model, analyzing various biological and performance metrics.
  • - The GTE + ACR combination showed the most significant improvements in swimming duration and lower lactate levels compared to the negative control group, indicating enhanced endurance.
  • - While GTE helps in body recovery and immune response, ammonium carbonate specifically boosts physical performance. However, combining GTE with ammonium salts does not yield a clearly beneficial effect.
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In mammals, glycated serum albumin (gSA) contributes to the pathogenesis of many metabolic diseases by activating the receptors (RAGE) for advanced glycation end products (AGEs). Many aspects of the gSA-RAGE interaction remain unknown. The purpose of the present paper was to study the interaction of glycated human albumin (gHSA) with RAGE using molecular modeling methods.

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The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD).

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Being one of the main proteins in the human body and many animal species, albumin plays a decisive role in the transport of various ions, electrically neutral molecules and in maintaining the colloid osmotic pressure of the blood [...

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The etiology and pathogenesis of Alzheimer's disease are multifactorial, so one of the treatment strategies is the development of the drugs that affect several targets associated with the pathogenesis of the disease. Within this roadmap, we investigated the interaction of several substituted 1,3-dihydro-2-oxo-1-benzimidazol-2-ones with their potential molecular targets: cholinesterases (ChE) and three types of the G-protein-coupled serotonin receptors (5-HTR) 5-HT, 5-HT and 5-HT (5-HTR, 5-HTR and 5-HTR, respectively). A microplate modification of the Ellman method was used for the biochemical analysis of the inhibitory ability of the drugs towards ChE.

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The esterase status of blood plasma can claim to be one of the universal markers of various diseases; therefore, it deserves attention when searching for markers of the severity of COVID-19 and other infectious and non-infectious pathologies. When analyzing the esterase status of blood plasma, the esterase activity of serum albumin, which is the major protein in the blood of mammals, should not be ignored. The purpose of this study is to expand understanding of the esterase status of blood plasma and to evaluate the relationship of the esterase status, which includes information on the amount and enzymatic activity of human serum albumin (HSA), with other biochemical parameters of human blood, using the example of surviving and deceased patients with confirmed COVID-19.

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Organophosphates (OPs) are toxic chemicals produced by an esterification process and some other routes. They are the main components of herbicides, pesticides, and insecticides and are also widely used in the production of plastics and solvents. Acute or chronic exposure to OPs can manifest in various levels of toxicity to humans, animals, plants, and insects.

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The delayed effects of acute intoxication by organophosphates (OPs) are poorly understood, and the various experimental animal models often do not take into account species characteristics. The principal biochemical feature of rodents is the presence of carboxylesterase in blood plasma, which is a target for OPs and can greatly distort their specific effects. The present study was designed to investigate the nephrotoxic effects of paraoxon (O,O-diethyl O-(4-nitrophenyl) phosphate, POX) using three models of acute poisoning in outbred Wistar rats.

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Serum albumin possesses esterase and pseudo-esterase activities towards a number of endogenous and exogenous substrates, but the mechanism of interaction of various esters and other compounds with albumin is still unclear. In the present study, proton nuclear magnetic resonance (H NMR) has been applied to the study of true esterase activity of albumin, using the example of bovine serum albumin (BSA) and -nitrophenyl acetate (NPA). The site of BSA esterase activity was then determined using molecular modelling methods.

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Being one of the main proteins in the human body and many animal species, albumin plays a decisive role in the transport of various ions-electrically neutral and charged molecules-and in maintaining the colloidal osmotic pressure of the blood. Albumin is able to bind to almost all known drugs, as well as many nutraceuticals and toxic substances, largely determining their pharmaco- and toxicokinetics. Albumin of humans and respective representatives in cattle and rodents have their own structural features that determine species differences in functional properties.

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Background: Ambient temperature is predicted to rise in Saudi Arabia, and how this will impact the health of its population has not been investigated. Saudi Arabia is one of the top ten countries with the highest prevalence of diabetes. The current study investigates the correlation between ambient temperature and HbA1c levels in a group of Saudis in Riyadh.

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As a carrier of many biologically active compounds, blood is exposed to oxidants to a greater extent than the intracellular environment. Serum albumin plays a key role in antioxidant defence under both normal and oxidative stress conditions. This review evaluates data published in the literature and from our own research on the mechanisms of the enzymatic and non-enzymatic activities of albumin that determine its participation in redox modulation of plasma and intercellular fluid.

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Background: Glycated haemoglobin (HbA1c) is the gold standard measurement in the screening, diagnosis and monitoring of diabetes mellitus. Saudi Arabia has a high prevalence of diabetes mellitus that is expected to rise, and the HbA1c test is commonly used in the screening, diagnosis and monitoring of diabetes.

Objective: This study aims to assess the impact of age and gender on HbA1c levels, and the influence of menopausal status on HbA1c variation in a large group of Saudis.

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Introduction: The impact of Ramadan fasting, a type of intermittent fasting, on the management of diabetes has not been well investigated. Physical activity, sleep duration, and time of sleep are susceptible to alterations during Ramadan due to the changes in the times and numbers of meals. This study compared physical activity and sleep patterns of individuals with type 2 diabetes mellitus (T2DM) during and after Ramadan using the international physical activity questionnaire (IPAQ) and a Fitbit Flex 2 accelerometer.

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Second messenger nicotinic acid adenine dinucleotide phosphate (NAADP) triggers Ca release via two-pore channels (TPCs) localized in endolysosomal vesicles. The aim of the present work is to evaluate the role of TPCs in the action of norepinephrine (NE), angiotensin II (AngII), vasopressin (AVP), and 5-hydroxytriptamine (5-HT) on free cytoplasmic calcium concentration ([Ca]) in smooth muscle cells (SMCs) isolated from rat aorta and on aorta contraction. To address this issue, the NAADP structural analogue and inhibitor of TPCs, NED 19, was applied.

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Poisoning by organophosphates (OPs) takes one of the leading places in the total number of exotoxicoses. Detoxication of OPs at the first stage of the poison entering the body could be achieved with the help of DNA- or RNA-aptamers, which are able to bind poisons in the bloodstream. The aim of the research was to develop an approach to rational in silico design of aptamers for OPs based on the example of paraoxon.

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Objective: To quantify the survival of Clostridium difficile spores on hospital bed sheets through the United Kingdom National Health System (UK NHS) healthcare laundry process (Health Technical Memorandum (HTM) 01-04) in vitro and on bed sheets from patients with C. difficile through the commercial laundry.

Methods: Clostridium difficile spores were inoculated onto cotton sheets and laundered through a simulated washer extractor cycle using an industrial bleach detergent with sodium hypochlorite 15% and peracetic acid sour 14% (acetic acid and hydrogen peroxide; pH, 2-4).

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Water hyacinth (Eichhornia crassipes) has been used for environmentally sustainable phytoremediation of water, though its use has been geographically restricted. For the first time we extend its geographical reach by investigating its potential for clean-up of water from a highly polluted British river (Nant-Y-Fendrod, a tributary of the River Tawe). Investigations using the plant were conducted at three levels: a bench-scale study using polluted river water and synthetic solutions; an in-situ trial using water hyacinth within the Nant-Y-Fendrod; and a bankside trial to pump and treat river water.

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Endothelium is a community of endothelial cells (ECs), which line the blood and lymphatic vessels, thus forming an interface between the tissues and the blood or lympha. This strategic position of endothelium infers its indispensable functional role in controlling vasoregulation, haemostasis, and inflammation. The state of endothelium is simultaneously the cause and effect of many diseases, and this is coupled with modifications of endothelial phenotype represented by markers and with biochemical profile of blood represented by biomarkers.

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The albumin molecule, in contrast to many other plasma proteins, is not covered with a carbohydrate moiety and can bind and transport various molecules of endogenous and exogenous origin. The enzymatic activity of albumin, the existence of which many scientists perceive skeptically, is much less studied. In toxicology, understanding the mechanistic interactions of organophosphates with albumin is a special problem, and its solution could help in the development of new types of antidotes.

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Glycosaminoglycans (GAGs) in the urine of Wistar rats, and on the surface of the epithelium and lamina propria of the bladder, were quantitatively assessed before and after acute intoxication with paraoxon or cyclophosphamide. Paraoxon was administered subcutaneously (s.c.

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In blood vessels, serotonin 5-HT2B receptors mainly mediate relaxation, although their activation by the selective agonist BW723C86 is known to exert contraction of aorta in deoxycorticosterone acetate (DOCA)-salt and N(omega)-nitro-l-arginine (l-NAME) hypertensive rats [Russel et al., 2002; Banes et al., 2003] and in mice with type 2 diabetes [Nelson et al.

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The volume of publications on the role of reactive oxygen species (ROS) in biological processes has been increasing exponentially over the last decades. ROS in large amounts clearly have detrimental effects on cell physiology, whereas low concentrations of ROS are permanently produced in cells and play a role as signaling molecules. An imbalance in ROS production and defense mechanisms can lead to pathological vascular remodeling, atherosclerosis being among them.

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