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1.
Arch Environ Contam Toxicol ; 49(4): 504-10, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16170449

ABSTRACT

Preservation of a healthy environment is a very important task, especially in the time of the total industrial revolution. Therefore, attempts to find new additional biomarkers of contamination are welcomed. For this aim, the functional and antioxidant properties of mussel Mytilus galloprovincialis proteins and the heavy metals Cd and Pb were explored. Mussels were collected in contaminated and noncontaminated sites in the Varna area of the Bulgarian Black Sea coast. Proteins were extracted from mussel entire soft tissue and analyzed using instrumental (Fourier transform infrared [FT-IR] spectroscopy, fluorescence, atomic absorption spectrophotometry), and biochemical (2,2'-azinobis 3-ethylbenzothiazoline-6-sulfonate) radical cation [ABTS(.+)]) methods. It was found that mussel proteins from the contaminated sites had specific qualitative changes: partial unfolding of the alpha-helix, slight shift in amide I bands, increased hydrophobicity, and fluorescent intensity in native and denatured samples. In the same mussel samples, an increased radical-scavenging capacity and increased contents of Cd and Pb in entire soft tissue were registered. Therefore, the above-mentioned indices could be used as additional biomarkers of sea water contamination.


Subject(s)
Mytilus/chemistry , Proteins/chemistry , Water Pollutants, Chemical/analysis , Animals , Antioxidants/analysis , Benzothiazoles , Biomarkers , Cadmium/analysis , Chemical Phenomena , Chemistry, Physical , Chromatography, Gel , Exocrine Glands/chemistry , Gills/chemistry , Indicators and Reagents , Lead/analysis , Metals, Heavy/analysis , Spectrometry, Fluorescence , Spectrophotometry, Atomic , Spectroscopy, Fourier Transform Infrared , Sulfonic Acids/chemistry , Urea/chemistry , Water Pollutants, Chemical/metabolism
2.
J Pept Res ; 59(2): 71-8, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11906609

ABSTRACT

The present report describes application of advanced analytical methods to establish correlation between changes in human serum proteins of patients with coronary atherosclerosis (protein metabolism) before and after moderate beer consumption. Intrinsic fluorescence, circular dichroism (CD), differential scanning calorimetry and hydrophobicity (So) were used to study human serum proteins. Globulin and albumin from human serum (HSG and HSA, respectively) were denatured with 8 m urea as the maximal concentration. The results obtained provided evidence of differences in their secondary and tertiary structures. The thermal denaturation of HSA and HSG expressed in temperature of denaturation (Td, degrees C), enthalpy (DeltaH, kcal/mol) and entropy (DeltaS kcal/mol K) showed qualitative changes in these protein fractions, which were characterized and compared with fluorescence and CD. Number of hydrogen bonds (n) ruptured during this process was calculated from these thermodynamic parameters and then used for determination of the degree of denaturation (%D). Unfolding of HSA and HSG fractions is a result of promoted interactions between exposed functional groups, which involve conformational changes of alpha-helix, beta-sheet and aperiodic structure. Here evidence is provided that the loosening of the human serum protein structure takes place primarily in various concentrations of urea before and after beer consumption (BC). Differences in the fluorescence behavior of the proteins are attributed to disruption of the structure of proteins by denaturants as well as by the change in their compactability as a result of ethanol consumption. In summary, thermal denaturation parameters, fluorescence, So and the content of secondary structure have shown that HSG is more stable fraction than HSA.


Subject(s)
Blood Proteins/chemistry , Serum Albumin/chemistry , Serum Globulins/chemistry , Calorimetry, Differential Scanning , Circular Dichroism , Humans , Protein Conformation , Protein Denaturation , Solutions , Spectrometry, Fluorescence , Spectrophotometry
3.
J Agric Food Chem ; 49(11): 5595-601, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714365

ABSTRACT

Intrinsic fluorescence (IF), surface hydrophobicity (S(o)), electrophoresis, amino acid analysis, circular dichroism (CD), and differential scanning calorimetry (DSC) were used to study folded and unfolded soluble proteins from Amaranthus hypochondriacus (A. h.) and soybean (S). Globulin (Glo) and albumin subfractions (Alb-1 and Alb-2) were extracted from A. h. and S and denatured with urea. Electrophoretic and functional properties indicated a significant correlation between soluble protein fractions from soybean and amaranth. The protein fractions shared some common electrophoretic bands as well as a similar amino acid composition. The larger percent of denaturation in protein fractions, which is associated with enthalpy and the number of ruptured hydrogen bonds, corresponds to disappearance of alpha-helix. The obtained results provided evidence of differences in their secondary and tertiary structures. The most stable was Glo followed by the Alb-2 fraction. Predicted functional changes in model protein systems such as pseudocereals and legumes in response to processing conditions may be encountered in pharmaceutical and food industries. These plants can be a substitute for some cereals.


Subject(s)
Amaranthus/chemistry , Amino Acids/analysis , Soybean Proteins/chemistry , Albumins/chemistry , Calorimetry, Differential Scanning , Circular Dichroism , Electrophoresis, Polyacrylamide Gel , Globulins/chemistry , Solubility , Spectrometry, Fluorescence
4.
J Agric Food Chem ; 49(3): 1441-5, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11312877

ABSTRACT

The aim of this study was to evaluate the influence of beer consumption (BC) on the functional and structural properties of human serum proteins (HSP). Thirty-eight volunteers (after coronary bypass) were divided into two groups: experimental (EG) and control (CG). Nineteen volunteers of the EG consumed 330 mL per day of beer (about 20 g of alcohol) for 30 consecutive days. The CG volunteers consumed mineral water instead of beer. Blood samples were collected from EG and CG patients before and after the experiment. Albumin (Alb), globulin (Glo), and methanol-precipitable proteins (MPP) from human serum were denatured with 8 M urea. Fluorescence and electrophoresis were employed in order to elucidate urea-induced conformational changes and structural behavior of proteins. The measured fluorescence emission spectra were used to estimate the stability of native and denatured protein fractions before and after BC. It was found that before BC the fractions most stable to urea denaturation were Glo, Alb, and MPP fractions. After BC in most of the beer-consuming patients (EG) some changes in native and denatured protein fractions were detected: a tendency to lower stability and minor structural deviations. These qualitative changes were more profound in MPP than in Alb and Glo. Thus, Glo is more resistible to alcohol influence than Alb, which in turn is more resistible than MPP. No serum protein changes were detected in patients of CG.


Subject(s)
Beer , Blood Proteins/chemistry , Coronary Artery Bypass , Humans , Lipids/blood , Male , Mineral Waters , Protein Conformation , Protein Denaturation , Serum Albumin/chemistry , Serum Globulins/chemistry , Spectrometry, Fluorescence , Urea
5.
J Agric Food Chem ; 49(2): 952-7, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11262055

ABSTRACT

Dietary fibers, major phenolics, main minerals, and trace elements in persimmons and apples were analyzed and compared in order to choose a preferable fruit for an antiatherosclerotic diet. Fluorometry and atomic absorption spectrometry following microwave digestion were optimized for the determination of major phenolics and minerals. Total, soluble, and insoluble dietary fibers, total phenols, epicatechin, gallic and p-coumaric acids, and concentrations of Na, K, Mg, Ca, Fe, and Mn in whole persimmons, their pulps, and peels were significantly higher than in whole apples, pulps, and peels (P < 0.01-0.0025). Conversely, the contents of Cu and Zn were higher in apples than in persimmons. In persimmons and apples all of the above components were higher in their peels than in whole fruits and pulps. The relatively high contents of dietary fibers, total and major phenolics, main minerals, and trace elements make persimmon preferable for an antiatherosclerotic diet.


Subject(s)
Dietary Fiber/analysis , Fruit/chemistry , Minerals/analysis , Phenol/analysis , Rosales/chemistry , Arteriosclerosis/prevention & control , Diet , Humans , Trace Elements/analysis
7.
J Protein Chem ; 19(8): 637-42, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11307947

ABSTRACT

The unfolding of human serum proteins (HSP) was studied by measuring the intrinsic fluorescence intensity at a wavelength of excitation corresponding to tryptophan's or typosine's fluorescence and surface hydrophobicity. The maxima emission wavelengths (lambdamax) of human serum albumin (HSA) and human serum globulin (HSG) before beer consumption (BC) were 336.0 and 337.0 nm and after BC shifted to 335.0 and 334.0 nm, respectively. The surface hydrophobicity slightly increased after BC. In a solution of 8 M urea the lambdamax of BSA shifted to 346.4 and that of BSG to 342.5 nm. In contrast, in the same solution but after BC the lambdamax positions of HSA and HSG shifted to 355.9 and 357.7 nm, respectively. A decrease in fluorescence intensity, a shift in the maximum of emission, and an increase in surface hydrophobicity which reflected unfolding of proteins were observed. Here we provide evidence that the loosening of the HSP structure takes place primarily in various concentrations of urea before and after beer consumption. Differences in the fluorescence behavior of the proteins are attributed to disruption of the structure of proteins by denaturants as well as by the change in their compactability as a result of ethanol consumption.


Subject(s)
Albumins/chemistry , Blood Proteins/chemistry , Globulins/chemistry , Tryptophan/chemistry , Beer , Fluorescence , Humans , Protein Conformation , Protein Denaturation , Protein Folding
8.
J Nutr Biochem ; 10(6): 367-71, 1999 Jun.
Article in English | MEDLINE | ID: mdl-15539312

ABSTRACT

Recent studies have shown that dietary fiber and polyphenols of vegetables and fruits improve lipid metabolism and prevent the oxidation of low density lipoprotein cholesterol (LDL-C), which hinder the development of atherosclerosis. The goal of this study was to measure the total polyphenol and dietary fiber contents of some tropical fruits (i.e., pineapple, wax apple, rambutan, lichi, guava, and mango) and compare the results to the content of these substances in the better characterized persimmon. It was found that lichi, guava, and ripe mango (cv. Keaw) have 3.35, 4.95, and 6.25 mg of total polyphenols in 100 g fresh fruit, respectively. This is significantly higher than in persimmon, pineapple, wax apple, mature green mango, and rambutan [P < 0.0005 for pineapple (Smooth Cayene variant), wax apple, persimmon, rambutan, mature green mango (cv. Keaw); the value of P < 0.001 is found only for pineapple (Phuket, Queen variant)]. The same relationship was observed for the contents of gallic acid and of dietary fiber. It can be supposed that among the studied fruit, lichi, guava, and ripe mango may be preferable for dietary prevention of atherosclerosis.

9.
J Nutr ; 128(11): 2023-7, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9808659

ABSTRACT

The effect of dietary persimmon (Pers, 7.0%) on lipid metabolism and antioxidant activity was investigated in 40 male Wistar rats adapted to cholesterol-free or 1% cholesterol diets. The rats were divided in four groups of 10. The basal diet contained wheat starch, casein, soybean oil, and mineral and vitamin mixtures. The control group (C) consumed the basal diet. To the basal diet were added 7 g/100 g dry persimmon (Pers), 1 g/100 g cholesterol (Chol), or both (Chol/Pers). The experiment lasted 4 wk. Plasma total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), triglycerides (TG), total phospholipids (TPH), HDL phospholipids (HDL-PH), lipid peroxides (LP) and liver TC concentrations were measured. Groups did not differ before the experiment. In the Chol/Pers vs. Chol group, the persimmon-supplemented diet significantly (P < 0.05) lessened the rise in plasma lipids due to dietary cholesterol: TC (3.88 vs. 4. 88 mmol/L; -20%), LDL-C (2.24 vs. 3.27 mmol/L; -31%), TG (0.72 vs. 0. 89 mmol/L; -19%), LP (2.20 vs. 3.25 mmol/L; -32%) and TC in liver (32.8 vs. 49.9 micromol/g; -34%), (P < 0.001). The Chol/Pers diet significantly reduced the decrease in HDL-PH due to dietary cholesterol (0.73 vs. 0.58 mmol/L; -25.8%, P < 0.001) and decreased the level of TPH (1.32 vs. 1.73 mmol/L; -23%, P < 0.001). Persimmon in rats fed the basal diet without cholesterol did not significantly affect the variables measured. These results demonstrate that persimmon possesses hypolipidemic and antioxidant properties that are evident when persimmon is added to the diet of rats fed cholesterol. These properties are attributed to its water-soluble dietary fiber, carotenoids and polyphenols.


Subject(s)
Cholesterol, Dietary/administration & dosage , Diet , Fruit , Lipids/blood , Animals , Cholesterol/blood , Cholesterol/metabolism , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Lipid Peroxides/blood , Liver/metabolism , Male , Phospholipids/blood , Rats , Rats, Wistar , Triglycerides/blood
10.
J R Soc Med ; 91(12): 631-3, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10730110

ABSTRACT

Moderate consumption of ethanol lowers mortality from coronary artery disease, and one of the possible mechanisms is an antiarrhythmic action. We therefore investigated the effect of a small daily dose of beer on plasma electrolytes. 52 men who seldom drank alcohol, clinically stable more than one year after coronary bypass surgery, were randomized to drink either 330 mL beer (containing about 20 g ethanol) or mineral water with similar potassium, magnesium, calcium and sodium content daily for 30 days. Plasma electrolytes and liver function indices, and also heart rate, blood pressure and weight, were measured before and after the trial period. The only significant before-and-after difference was in the group consuming beer, whose plasma magnesium rose from 0.89 (SD 0.01) to 0.98 (SD 0.02) mmol/L (P < 0.0025). This level of beer consumption did no obvious harm to liver function and its possibly beneficial effect on plasma magnesium deserves further investigation.


Subject(s)
Beer , Coronary Disease/prevention & control , Magnesium/blood , Mineral Waters/administration & dosage , Aged , Coronary Disease/mortality , Coronary Disease/therapy , Humans , Male , Middle Aged
11.
J Intern Med ; 242(3): 219-24, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9350166

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the influence of moderate beer consumption on lipid metabolism and antioxidant activity in patients (pts) with coronary artery disease (CAD). SUBJECTS: Forty-eight male pts with CAD not alcohol beverages consumers were randomly divided into experimental (EG) and control (CG) groups, 24 pts each. SETTING: Rehovot University Hospital, Israel. INTERVENTION: Every patient of the EG during a period of 30 consecutive days consumed 330 ml of Maccabee beer (> 20 g of alcohol). The pts of the CG did not consume alcohol during the trial period. METHODS: A wide range of tests including total cholesterol, LDL-C, HDL-C, total tocopherol and alpha-tocopherol. RESULTS: Only in the pts of the EG were found a tendency to an increase of the level of HDL-C and a statistically significant rise in the level of total tocopherol (P < 0.025) and alpha-tocopherol (P < 0.025). CONCLUSIONS: Even a short period of moderate beer consumption leads to some favourable biochemical changes in blood of pts with CAD which are widely regarded as indicators of CAD prevention.


Subject(s)
Alcohol Drinking , Beer , Coronary Artery Disease/blood , Lipid Peroxidation , Lipids/blood , Vitamin E/blood , Cholesterol/blood , Humans , Male , Prospective Studies , Treatment Outcome , Triglycerides/blood
12.
J Intern Med ; 241(1): 47-51, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9042093

ABSTRACT

OBJECTIVES: To evaluate the influence of a short period of moderate beer consumption on the status of the thrombolitic activity in patients with coronary artery disease (CAD). SUBJECTS AND DESIGN: From 28 patients with two- or three-vessel CAD 22 were randomly assigned to an experimental group (EG) and six to control group (CG). Before and after completion of the study every one of the 28 patients was examined and a wide range of laboratory tests was performed. SETTING: A University Hospital in Israel. INTERVENTION: Of the EG, 22 patients consumed 330 mL of beer day-1 (20 g of alcohol) for the 30-day period in addition to the usual antiatherosclerotic diet. Patients of the CG did not consume alcohol beverages. MAIN OUTCOME MEASURES: Fibrinogen, prothrombin time (PT), coagulant activity of Factor VII (F VIIc) and Factor VII antigen (F VIIag), and plasminogen activator inhibitor (PAI) levels were studied. RESULTS: After the investigation a statistically significant decrease was found in F VIIc (P < 0.01) and F VIIag (P < 0.001) and to a lesser extent a decrease in the value of PAI. Fibrinogen and PT remained unchanged in the EG also. CONCLUSIONS: Even a short period of moderate beer consumption results in a decrease in thrombogenic activity. The only sensitive tests were F VIIc and F VIIag. The decrease in thrombogenic activity may be the main cause of decreased mortality in patients with CAD who consume moderate quantities of alcoholic beverages.


Subject(s)
Alcohol Drinking , Beer , Blood Coagulation Factors/drug effects , Blood Coagulation/drug effects , Coronary Disease/blood , Ethanol/pharmacology , Aged , Blood Coagulation Factors/metabolism , Factor VII/metabolism , Fibrinogen/metabolism , Humans , Male , Middle Aged , Plasminogen Activators/antagonists & inhibitors , Prothrombin Time
13.
Article in Russian | MEDLINE | ID: mdl-3776410

ABSTRACT

The effect of strophanthin (S) on the status of the general and cerebral hemodynamics was investigated in 35 patients with ischemic stroke (IS). The central hemodynamics was studied with the help of dye dilution. The blood circulation in the system of the internal carotid artery was determined with the help of ophthalmoplethysmography and ophthalmodynamometry. S was infused intravenously in daily doses of 0.25 ml of 0.05% solution. S had a positive inotropic influence on the myocardium; the diastolic retinal pressure simultaneously decreased while the minute volume of blood in the eyes increased. The authors substantiate the possibility of the direct effect of S on the tonus of the cerebral vessels and advisability of its application in patients with IS even when there are no evident clinical signs of chronic cardiac failure.


Subject(s)
Brain Ischemia/drug therapy , Hemodynamics , Strophanthins/therapeutic use , Aged , Blood Pressure , Blood Volume , Brain/blood supply , Cardiac Output , Eye/blood supply , Female , Humans , Male , Middle Aged , Vascular Resistance
14.
Bibl Cardiol ; (35): 197-201, 1976.
Article in English | MEDLINE | ID: mdl-825099

ABSTRACT

A measurement of STI and Bcg was used to provide an objective evaluation of the results of isosorbide dinitrate treatment of 120 patients suffering from coronary artery disease. Normalization of STI and Bcg in patients reporting subjective improvement following treatment was observed in a greater number of cases than the number with ECG normalization. Therefore, it can be concluded that after effective treatment measurement of STI AND Bcg provides a more sensitive means of objective evaluation than ECG.


Subject(s)
Coronary Disease/drug therapy , Heart Function Tests/methods , Adult , Aged , Angina Pectoris/drug therapy , Ballistocardiography , Carotid Arteries , Coronary Disease/diagnosis , Coronary Disease/physiopathology , Drug Evaluation , Electrocardiography , Heart Conduction System/physiopathology , Heart Ventricles/physiopathology , Hemodynamics/drug effects , Humans , Isosorbide Dinitrate/therapeutic use , Male , Middle Aged , Nitroglycerin/therapeutic use , Phonocardiography , Pulse
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