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Naturally Occurring Polymers—Animals
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
Genes are involved in all aspects of our lives. Someone has said we are what we eat. We can extend this to say that we become what our genes do with what we eat. There is a group of genes called apolipoprotein or APO genes. There are four basic types of APO genes interestingly known as A, B, C, and E (no explanation for what happened to D; known as APOA, APOB, etc.). Here, we will focus on a specific gene that appears on chromosome 19 known as APOE. As we eat, the various food parts are digested, broken down. Both fats and cholesterol are brought through our bloodstream by lipoproteins, some called very-low-density lipoproteins (VLDLs). These fats and cholesterol are brought to various parts of the body to act as fuel and building blocks. As some of the triglycerides are delivered, the proteins now are called simply low-density lipoprotein, or LDL, known to many of us as “bad cholesterol.” After delivering the cholesterol, it becomes high-density lipoproteins (HDL), also known to us as good cholesterol and then returns to the liver to be replenished with cholesterol and fats. The APOE protein acts to affect the transfer between VLDL proteins and a receptor on a cell that needs some triglycerides. APOB serves a similar role except in delivering cholesterol. Thus, the presence and effectiveness of genes that code for the APO genes help control our weight and health, affecting such items as buildup on our arteries.
Steroids: Arthritis, Fertility, Heart Attacks, And Home Run Records
Published in Richard J. Sundberg, The Chemical Century, 2017
The association between cholesterol levels and cardiovascular disease began to be recognized around 1900, when it was observed that animals fed high cholesterol diets developed atherosclerosis. A genetic disorder, familial hypercholesterolemia, is characterized by both very high cholesterol levels and early onset of cardiovascular disease. The Framingham Heart Study of the National Institutes of Health provided convincing statistical evidence of a correlation between blood cholesterol levels and the incidence of heart disease.6 It was also recognized that a high ratio of low-density lipoprotein (LDL) to high-density lipoprotein (HDL) was a risk factor for cardiovascular disease.7 These values, in turn, are influenced by dietary intake, with saturated fat and trans-fat tending to increase LDL while unsaturated fats decrease LDL. Cardiovascular disease is a major cause of death in most of the developed world and accounts for about 15% of deaths in the United States, of which about 15% are <65 years of age. There are associations of cardiovascular diseases with several factors, including those that constitute the metabolic syndrome, namely obesity, hypertension, and insulin resistance.
Biochemistry
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
78 Nicotinic acid Niacin Lipoprotein synthesis inhibitor Soluble in water (15 g/l at 20 °C), alkali hydroxides, propylene glycol, water (150 g/l at 100 °C), ethanol (12.5 g/l at 25 °C), DMSO (25 mg/mL), methanol, carbonates, and water (15 g/l at 20 °C). Insoluble in diethyl ether. HMG-CoA reductase inhibitor (statin) Soluble in non-polar solvents. Reduction of LDL cholesterol levels
Four weeks of high-intensity interval training (HIIT) improve the cardiometabolic risk profile of overweight patients with type 1 diabetes mellitus (T1DM)
Published in European Journal of Sport Science, 2021
Katharina Minnebeck, Elena Vorona, Sarah Zinn, Reinhold Gellner, Jens Hinder, Stefan-Martin Brand, Iyad Kabar, Florian Alten, Boris Schmitz
With respect to exercise interventions in T1DM, it has been reported that MICT has the potential to reduce LDL-C levels in T1DM patients. These interventions involved exercise programmes lasting 3–4 months decreasing LDL-C by 8–14%, (Chimen et al., 2012) comparable to the mean reduction of ∼7% in the overweight group of our study. It might also be of interest that sex differences in response to HIIT might exist since we observed that HDL levels may have increased in females but not in males. However, the detected ES indicated a small effect for improvement of LDL-C and the current study was not designed to analyse sex effects. Thus, these findings need further validation.
Boundary layer considerations in a multi-layer model for LDL accumulation
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Marcello Iasiello, Kambiz Vafai, Assunta Andreozzi, Nicola Bianco
Inlet velocity effect is presented in Figure 7. It is shown that the boundary layer becomes thicker with lower velocities and also slightly higher for higher lumen radius. As expected, lower velocities result in a thicker boundary layer. For example, this means that physical exercise can possibly reduce LDL deposition. The lumen radius effects are presented in Figure 8. The boundary layer grows with the lumen radius and also slightly higher when transmural pressure increases. As mentioned earlier, this occurs because velocity gradients are lower.
Hyperlipidemia and male infertility
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Zainab Bubakr Hamad Zubi, Hamad Abdulsalam Hamad Alfarisi
Hyperlipidemia is an elevation of serum total cholesterol, low-density lipoprotein (LDL-c), very low density lipoprotein (VLDL), or triglycerides (TGs), or a low serum high-density lipoprotein (HDL-c) [1,2]. It is a common disease affecting 25% of adults in developed nations. In the United States, half of people of more than 65 years of age were treated with antihyperlipidaemic agents between 2007 and 2010 [3]. Worldwide, the incidence of dyslipidaemia is increasing in both low and high income countries [4]. Diet is an important factor that may induce hyperlipidemia. Modern diet which is highly constituted by fat, sugar and refined grains products is an important extrinsic factor for the development of this disease [5]. Hyperlipidemia is a major risk factor for the prevalence and severity of ischemic heart disease which together with stork are the primary causes of death [1]. Less recognized but growing in importance are the effects of hyperlipidemia on reproductive functions [6]. A growing evidence has linked dyslipidaemia and abnormal lipid metabolism with alterations in semen quality and fertility [7]. Hypercholesterolemia is a subclass of hyperlipidemia [9]. It is characterized by high serum LDL-c and blood cholesterol. High-cholesterol diet is the main factor in the development of hypercholesterolemia, which is a well-established risk factor for atherosclerosis and coronary heart disease [10,11]. Approximately 50% of the middle-aged adult population have been reported to have total cholesterol level above the normal range [12]. Cholesterol is an essential component for cell membrane composition, permeability, fluidity, endocytosis and signal transduction. It is the precursor of steroid hormones biosynthesis and its homeostasis is critical for male reproductive system. Thus, cholesterol must be strictly regulated for optimal cell functions as any disturbance in its homeostasis can affect male reproductive fitness and fertility [13].