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par Mohamed Ghermi, mercredi 18 novembre 2020, 11:16
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Interferon-γ (+874 T/A) and interleukin-10 (−1082 G/A) genes polymorphisms are associated with active tuberculosis in the Algerian population of Oran's city.

 

https://doi.org/10.1016/j.ijtb.2020.08.015

 

[ Modifié: jeudi 19 novembre 2020, 19:35 ]
 
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The standard genetic code multiplet structure as well as the correct degeneracies, class by class, are all extracted from the (unique) number 23!, the order of the permutation group of 23 objects.

Journal Reference: Symmetry: Culture and Science, Vol. 18, 2-3, 149-160, 2007.  

 
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This work aims at showing the relevance and the applications possibilities of the Fibonacci sequence, and also its q-deformed or "quantum" extension, in the study of the genetic code(s). First, after the presentation of a new formula, an indexed double Fibonacci sequence, comprising the first six Fibonacci numbers, is shown to describe the 20 amino acids multilets and their degeneracy as well as well as a characteristic pattern for the 61 meaningful codons. Next, the twenty amino acids, classified according to their increasing atom-number (carbon, nitrogen, oxygen and sulfur), exhibit several Fibonacci sequence patterns. Several mathematical relations are given, describing several atom-number patterns. Finally, a q-Fibonacci simple phenomenological model, with q a real deformation parameter, is used to describe, in a unified way, not only the standard genetic code, when q=1, but also all slight variations of the latter when q is near 1, as well as the case of the 21st amino acid (selenocysteine) and the 22nd one (pyrrolysine), also when q is near 1. As a by-product of this elementary model, we also show that, in the limit q=0, the number of amino acids reaches the value 6, in good agreement with old and still persistent claims that life, in its early development, could have used only a small number of amino acis. 

 
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This is the presentation for "Symmetry Festival 2013", Delft, the Netherlands 2-7 Aug. 2013. Completing the corresponding publication.

 
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The number of atoms in the four ribonucleotides uridine monophosphate (UMP), cytidine monophosphate (CMP), adenine monophosphate (AMP) and guanine monophosphate (GMP) is taken as a key parameter. A mathematical relation describing the condensation of the three basic sub-units a nucleobase, a ribose and a phosphate group, to form a ribonucleotide, is first obtained from this parameter. Next, the use of the latter and Euler's totient function is shown to lead to the atom number content of the 64 codons and also to Rakocevic's pattern "2x3456". Finally, selected sums of Fibonacci numbers are shown to lead to the nucleon number content of the amino acids in various degeneracy patterns , and also to the multiplet structure of the 20 amino acids as well as to the degeneracy.

[ Modifié: vendredi 13 novembre 2020, 21:36 ]
 
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لات

 
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Diabetes mellitus is a major risk factor for cardiovascular complications. The present study was designed to investigate the possible hypoglycaemic, hypolipidaemic and antioxidant effects of a lyophilised methanolic extract of Globularia alypum L. (Ga). Twenty rats with diabetes were divided into two groups that were fed a casein diet either with or without a Ga supplement for 28 d. Diabetes was induced in the rats by administration of a single dose of streptozotocin (50 mg/kg; intraperitoneally). Plasma total cholesterol (TC), TAG, VLDL-LDL-TC and HDL-TC and the content of final lipid peroxidation products reacting with thiobarbituric acid (TBARS) in several tissues, as well as the concentration of reduced glutathione (GSH) and antioxidant enzyme activities were evaluated. A significant reduction in plasma glucose was observed in rats treated with Ga (5.21 (SE 0.83) mmol/l) compared with untreated rats (27.4 (SE 0.21) mmol/l). TC, VLDL-LDL-TC and TAG were respectively 1.3-, 1.8- and 1.6-fold higher for Ga-treated rats than for untreated rats, whereas there was no significant difference in HDL-TC. Compared with the untreated group TBARS were diminished by 43, 51, 42 and 23% in liver, heart, brain and kidney respectively in the Ga-treated group, although in adipose tissue and gastrocnemus muscle the concentrations were similar for both groups. GSH levels were increased by 40, 25 and 36% in liver, brain and kidney respectively, whereas values in heart and muscle were similar. In liver and kidney superoxide dismutase (SOD), GSH peroxidase (GSH-Px), glutathione reductase and catalase (CAT) activities were increased significantly in Ga-treated rats compared with untreated rats (P<0.05). Moreover, for Ga-treated rats SOD activity was increased by 22% in muscle, while GSH-Px and CAT activities were 1.3- and 1.4-fold higher in heart compared with untreated rats. Administration of Ga to rats with diabetes leads to lower glycaemia and plasma lipids. Moreover, this plant exerts a beneficial action against tissue lipid peroxidation by enhancing antioxidant enzyme activities.

 
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Portulaca oleracea (Po) has been used as one of the traditional edible and medicinal plant in Algeria to treat diabetes and enhancing immunity. The aim of the present study was to investigate the possible antihyperglycemiant and hypolipemiant effects of Po lyophilized aqueous extract, in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in male Wistar rats (n=12), weighing 263±5g, by a single intraperitoneal injection of STZ (60mg/kg body weight). Diabetic rats were divided into two groups. The untreated group received a 20% casein diet (D) and the treated group received the same diet supplemented with Po lyophilized aqueous extract (1 g/100 g diet) (DPo), for 4 weeks. According to thin layer chromatography assay, the main chemical groups detected are flavonoids, alkaloids, and terpenoids. During all the experiment in spite of similar food intake in the 2 groups, there was a significant decrease in the body weight. At d28, in Po treated vs untreated diabetic group, glycemia and glycosylated haemoglobin (HbA1c) were reduced by 61% and 41%, respectively, whereas insulinemia was similar. Plasma cholesteryl esters (CE), triacylglycerols (TG) and phospholipids (PL) concentrations were decreased by 48%, 53% and 62%, respectively. The hypolipidemic effect induced by Po extract was due to the reduction of total cholesterol (TC) in VLDL (-28%), LDL-HDL1 (-51%) and C-HDL3 (-21%), and a decrease of TG in VLDL (-71%), LDL-HDL1 (-68%) and HDL2 (-30%). Quantitatively, VLDL, LDL-HDL1, HDL2 and HDL3 lipoproteins mass was respectively 2.9-, 4.1-, 1.5- and 2.5-fold lower and concomitant with the reduced levels of unesterified cholesterol (UC) (-55%), CE (-17%) and -PL (-72%) in VLDL fraction, and UC (-36%), -CE (-56%) and PL (-82%), in LDL-HDL1. Po treatment improved lecithin:cholesterol acyltransferase (LCAT) activity by 48% and its cofactor-activator, the plasma apolipoprotein (apo) A-I by 52%.. HDL3-UC (acyl group acceptor) and -PL (enzyme substrate) were diminished respectively by 47% and 82%, whereas HDL2-CE concentrations (product of LCAT reaction) were increased by 44%. In STZ-induced diabetic rat, Portulaca oleracea lyophilized aqueous extract possesses antihyperglycemiant and hypolipemiant effect by improving lipoprotein profiles. Po extract may be useful in the prevention and treatment of diabetes and dylipidemia.

 
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The effects of Portulaca oleracea (Po) lyophilized aqueous extract were determined on the serum high-density lipoproteins (HDL2 and HDL3) amounts and composition, as well as on lecithin: cholesterol acyltansferase (LCAT) activity. Methods Male Wistar rats (n = 12) were fed on 1% cholesterol-enriched diet for 10 days. After this phase, hypercholesterolemic rats (HC) were divided into two groups fed the same diet supplemented or not with Portulaca oleracea (Po-HC) (0.5%) for four weeks. Results Serum total cholesterol (TC) and triacylglycerols (TG), and liver TG values were respectively 1.6-, 1.8-, and 1.6-fold lower in Po-HC than in HC group. Cholesterol concentrations in LDL-HDL1, HDL2, and HDL3 were respectively 1.8, 1.4-, and 2.4-fold decreased in Po-HC group. HDL2 and HDL3 amounts, which were the sum of apolipoproteins (apos), TG, cholesteryl esters (CE), unesterified cholesterol (UC), and phospholipids (PL) contents, were respectively 4.5-fold higher and 1.2-fold lower with Po treatment. Indeed, enhanced LCAT activity (1.2-fold), its cofactor-activator apo A-I (2-fold) and its reaction product HDL2-CE (2.1-fold) were observed, whereas HDL3-PL (enzyme substrate) and HDL3-UC (acyl group acceptor) were 1.2- and 2.4-fold lower. Conclusion Portulaca oleracea reduces triglyceridemia, cholesterolemia, and improves reverse cholesterol transport in rat fed enriched-cholesterol diet, contributing to anti-atherogenic effects.

 
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The beneficial health effects of plant polyphenols were frequently attributed to their powerful hypolipemiant and antioxidant effects. We hypothesized that administration of Globularia alypum (Ga) lyophilized methanolic extract would ameliorate glycemia, lipid parameters, reverse cholesterol transport, as well as lipoproteins peroxidation, in diabetic rats. Diabetes was induced in male Wistar rats, weighing 250±10 g by a single intraperitoneal injection of streptozotocin (STZ) (55 mg/kg body weight). Diabetic rats (n=20) were divided into two groups, and fed during 4 weeks diets containing 20% casein (D) or a casein diet supplemented with a Ga extract (1 g/kg BW) (DGa). At d28, in DGa vs D group, glycemia was lowered by 81%, while insulinemia was markedly increased by 72%. Liver and serum lipid values were significantly decreased (P< 0.05). Lecithin:cholesterol acyltransferase (LCAT) activity was improved (+48%). Indeed, HDL3-PL (enzyme substrate) and HDL3-UC (acyl group acceptor) concentrations were respectively reduced by 50 and 52%, whereas HDL2-CE values (product of LCAT reaction) were increased (+35%). Atherogenicity ratios VLDL-LDL-C/HDL-C, TC/HDL-C and apoB/apoA were lowered respectively by 50%, 25% and 71%. Moreover, VLDL-LDL and HDL3peroxidation was decreased by 47 and 75%, respectively.In STZ-induced diabetic rat, Globularia alypum extract reduces glycemia, liver and serum lipids values, VLDL-LDL and HDL3 lipid peroxidation and ameliorates the reverse cholesterol transport. Therefore, Ga extract may be useful for preventing diabetes and lipid disorders.

[ Modifié: mercredi 15 juillet 2020, 08:59 ]