Methyl carbamate is a common herbicide for controlling undesired growth of weeds. The effect of methyl carbamate on proton translocation through chloroplast membranes has been investigated. pH changes produced by light-induced proton transport through chloroplast membranes in spinach were measured by a glass microelectrode. The measurement of pH changes in chloroplasts is useful for assessing toxic effects of the herbicide. Kinetic analysis of proton translocation shows that the rate of proton uptake follows a first-order and diminishes with the elevation of the carbamate concentration. The rate of outward leakage of accumulated protons through chloroplast membranes in the dark is significantly reduced in the presence of carbamate. Methyl carbamate only inhibits proton transport at the sub-millimolar level of the herbicide. The results suggest that methyl carbamate does not significantly inhibit proton transport through chloroplast membranes in its practical use. Thus, an excess use of methyl carbamate may not affect proton transport or the enzyme function in chloroplasts.
A lectin from the root tuber of Trichosanthes tricuspidatus has been isolated by affinity chromatography on cross-linked guar gum column. In SDS-PAGE the purified lectin (Trichosanthes tricuspidatus tuber agglutinin: TTTA) resolved as a single band at M-r 67 and 28 kDa in the absence and presence of beta-mercaptoethanol, respectively. It is a glycoprotein with 2.7 % of carbohydrate content. It agglutinated rabbit and human ABO erythrocytes. The agglutination was inhibited galactose and galactose containing sugars with increased beta-anomeric specificity.
High level of homocysteine (Hcy) is a significant independent, prothrombotic risk factor for atherothrombotic cardiovascular disease and associated with endothelial dysfunction. Plasminogen activator inhibitor 1 (PAI-1) and C-reactive protein (CRP) have also been associated with an increased risk for myocardial infarction. 43 patients with coronary vascular disease and 35 healty volunteer as control group were participated in this study. Total plasma homocysteine (tHcy), plasma PAI-1 and CRP level were measured. There were an increase in tHcy, PAI-1 and CRP levels patient group as compared to control. However, only correlation was found between tHcy and PAI-1. These result suggest that Hey may play an important role in the impaired fibrinolysis.
To investigate the effects of chronic whole-body microwave exposure, on serum Thyroid Stimulating Hormone (TSH), thyroxin (T-4), triiodothyronine (T-3), Cortisol, Growth Hormone (GH), Follicular Stimulating Hormone (FSH) and Estradiol concentrations, Wistar-albino female rats without treated and treated Vitamin C and Vitamin E were exposed to Microwave (MW) with a frequency of 9.450 MHz at the power density of 2.65 mW/cm(2) with corresponding specific absorption rate of 1.80 W/kg for 1h/day during 21 days. Vitamin C (150 mg/kg/day) and Vitamin E (150 mg/kg/day) were administrated during last seven exposure days to MW+Vit.C (n=8) and MW+Vit.E (n=8) groups respectively. Rectal temperatures were measured in all female rats. Serum levels of GH and FSH decreased (p<0.05, p<0.01 respectively) while estradiol levels increased in MW exposure group (p<0.05). But other hormones did not change in MW group (n=8). All hormone levels of rats treated with Vitamin C did not change (p>0.05). T-3 and T-4 hormones of exposed rats were found to be significant at MW +Vit.E group according to MW group (p<0.05). Rectal temperature differences were found to be significant in experimental groups according to sham group (n=8) (p<0.05). It was concluded that the changes of hormone concentrations under study was consistent with MW-induced thermal stimulation of Hypothalamic-Hypophysial-Adrenal (HHA) and Hypothalamic-Hypophysial-Thyroid (HHT) activity and Vitamin E might play role in changing T-3 and T-4 hormones.
Changes of pH produced by proton influx through chloroplast membranes in spinach were measured by a glass pH-microelectrode. Dimethyl-3,3'-dithiobispropionimidate dihydrochloride (DTBP) was used to study the functions of amino acid residues involved in proton flux. Kinetic results of proton translocation showed that the rate of proton pumping was considerably reduced in the presence of DTBP. The inhibitory effects increased with the concentration of DTBP. Proton pumping in illuminated spinach chloroplasts was completely inhibited at 2.1 mM of DTBP. The proton outward leakage in the dark was also affected. The decrease in proton pumping in the presence of DTBP suggested that cysteine residues played a role in proton pumping, and would appear to be covalently bound with some sulfhydryl groups. The subsequent interaction changed the conformation of the membrane. The use of DTBP would provide useful information on cross-linking properties between sulfhydryl groups of enzymes.
Artocarpin, an alpha-D-galactosyl specific lectin from Artocarpus lakoocha seeds was purified to homogeneity (M.W. approximate to 70,000) by ammonium sulfate fractionation followed by affinity chromatography on melibiose-agarose column. The mature seeds were homogenized in 250 mM sucrose solution with or without 5mM EDTA (Na salt) separately followed by differential centrifugation, whereby four fractions vir., wall, intermediate, microsomal pellets and soluble supernatant were obtained. The lectin activity was associated with all the fractions showing highest specific activity in the soluble supernatant. Localization of artocarpin in A. lakoocha seeds using monospecific anti-artocarpin and fluorescein isothiocyanate-conjugated goat anti-rabbit IgG by immunofluorescent staining technique revealed that the lectin was present in the entire cytosolic region and the cell wall with occasional appearance in the intercellular space. The above findings are in good agreement with those obtained from differential centrifugation studies.
Angiotensin-converting enzyme-like activity (ACELA) was determined in crude tissue homogenates of the marine polychaete, Nereis virens, by an HPLC assay using two synthetic substrates. The enzyme had a K-M of 2.8 mM and a V-max of 527 nmol/min/mg protein with the substrate N-(3-[2-furyl]acroyl)-phenylalanylglycylglycine (FAPGG) and a K-M Of 3.1 mM and a V-max of 22.3 nmol/min/mg protein with the substrate hippurylhistidylleucine (HHL). The enzyme had enhanced activity in the presence of added chloride with maximum activity at a chloride concentration of 300 mM. IC50 values with the specific angiotensin-converting enzyme (ACE) inhibitors lisinopril and captopril were 130 nM and 53 nM, respectively. Phosphoramidon, a potent inhibitor of other carboxypeptidases but not ACE, did not inhibit activity at 1 x 10(-3) M. The enzyme appeared to be soluble (not membrane associated) and ACELA was highest in coelomic fluid with a specific activity of 212 nmol min(-1) mg(-1). An M, value of 105 kDa was obtained for the enzyme by gel-filtration chromatography.
Antiviral and antitumoral effect of L-ascorbate (L-AsA) / Cu (II) have been established. We studied the antibacterial effect of L-ascorbate / Cu (II) and its mechanism. Oxidation products of ascorbate (AsA) produced in the presence of Cu(li). It has been known that these oxidation produts cause breaks in protein and nucleic acids. They also lead lipid peroxidation. Effects of different concentrations of AsA + CuCl2 on the growth of Bacillus subtilis and Staphylococcus aureus were investigated. Also subtoxic concentration of AsA / Cu (II) that affect the bacterial growth were established. It was found that the inhibitory concentration for B. subtilis and S. aureus was 4 mM AsA+ 100 mu M CuCl2. The growth of bacterial cells were followed spectrophotometrically. Also viable cell counts were made. Bacterial membranes isolated from control cells and bacteria grown in AsA+CuCl2 medium were applied on SDS-PAGE to show the changes occured in the membranes.
The presence of phosphonolipids formed from 2-aminoethylphosphonate in 3T3-L1 fibroblasts prevents their differentiation into adipocytes which is normally induced by the insulin mimetic Troglitazone, just as the phosphonolipids inhibit the differentiation induced by insulin itself (Smith, et al., Biochem. Arch. 8, 339-344 (1992)). Insulin and Troglitazone were found to act synergistically and produced a far greater induction of differentiation, as measured by the activity of glycerol-3-phosphate dehydrogenase, than either one alone. The presence of phosphonolipids prevented the differentiation which is induced by Troglitazone in control cells. When the 2-aminoethylphosphonate was washed out of the cells, Troglitazone induced differentiation which was comparable to that of control cells, unlike the results with insulin (Cleveland and Smith, Biochem. Arch. 14, 269-274 (1998)) where differentiation was restored only to 25% of normal upon washout of the 2-aminoethylphosphonate. The results suggest that while insulin and Troglitazone produce the same overall response in 3T3-L1 fibroblasts, the detailed process by which they do so may be different.
The present experiment was carried out to investigate whether 9450 MHz and 2450 MHz microwave exposure (MW) affect to the plasmid DNA of Escherichia coli puc 9 or not. Suspensions of E.coli puc 9 were exposed to microwave radiation at 2450 MHz (55,110,165,220 and 275 W for 30 and 60 second) and 9450 MHz (2.65mW/cm(2) for 10,20,40 and 60 minutes). However, plasmid DNA of E.coli puc 9 were also exposed to 9450 MHz (10,20,40 and 60 minutes) and 2450 MHz (55,110,165,220 and 275 W for 30 and 60 second) Microwave. After exposures of E.coli puc 9, the plasmid DNA were isolated and evaluated by AGE assay. We found that amount of plasmid DNA was not changed in 9450 MHz and 2450 MHz MW exposure. The difference of temperatures between before and after 2450 MHz MW exposures were found to be significant (P<0.01). It was concluded that E.coli puc 9 plasmid DNA was not affected by 9450 MHz and 2450 MHz Microwave radiation.
The effect of three amino acids (phenilalanine tyrosine triptophane) have been examined on differentiation of DNA, RNA, protein synthesis and cell growth in cell culture for Cicer arietinum L. cultivated in Murashige and Skoog medium. The Cicer arietinum L, culture were treated with 20, 40,60,80 and 100 mu g. levels of each phenolic amino acid. Amount of DNA, RNA, proteins and cell growth were determined by the levels in the time intervals of 24 h incubation time during 6 days. Obtained data were evaluated statistically Consequently, experimental results reveal that excessive amount of phenolic amino acids cause significant inhibition on RNA, protein and cell growth. Phenilalanine not strongly effect on DNA synthesis or activity of DNA polymerase was unaffected by phenilalanine but tyrosine and triptophane has significant effect on DNA. On the other hand, it has been supposed that extreme amount of phenolic amino acids may be converted to phenolic compounds by cell regulatory systems.
Extracellular hemagglutinin was excreted into the Richard's medium during the growth and development of the phytopathogenic fungus Macrophomina phaseolina. Extracellular hemagglutinin activity increased along with the growth of the organism, attaining maximum on seventh day and then gradually declined. The effect of varying concentrations of sucrose (carbon source) and KNO3 (nitrogen source) in the medium on the production of extracellular hemagglutinin was studied. The results indicate that high concentration of sucrose caused reduction in specific activity of the extracellular hemagglutinin whereas increasing the concentration of KNO3 led to higher specific activity. Maximum specific activity was observed when the concentrations of sucrose and KNO3 were both 5g.L-1 in the medium.
The aim of this work is to look at the absorption rates of Cu++ ions by Nasturtium officinale. For this purpose the solutions containing different concentrations of Cu++ ions (0.1; 0.3; 0.5; 1; 2; 3; 4 and 5 mgL(-1)) have been prepared. We have placed the plants of the relatively same size in each concentration. After 24, 48 and 72 h, the Cu++ concentrations in the solutions were measured for each concentrations. The plants exposed to the Cu++ ion concentrations of 0.1; 0.3 and 0.5 mgL(-1) were found to absorption all the metal ions present without any effects on the plants, while at the concentrations of 1, 2 and 3 mgL(-1), there is an accumulation at certain levels, despite some effects on the plants. However, at the solutions of 4 and 5 mgL(-1), it was observed that the plants died after a short time. In conclusion, Nasturtium officinale is able to absorption the lower concentrations of Cu++ ions but it seems that it is not able to accumulate the higher concentrations of Cu++ ions.
In vitro studies with lactoferrin (LF) at concentrations of 5, 25, 125, and 250mg/L inhibited the formation of hydroxyl radicals approximately by 6, 12, 14, and 23% respectively. No inhibitory effects were noticed on the superoxide anion-generating system at the same concentrations of LF tested (<4% at 250 mg/L). Following incubation of the gastric and intestinal mucosal tissues a concentration dependent protection against superoxide anion and hydroxyl radical induced lipid peroxidation was demonstrated by LF at 125 and 250 mg/L tested (gastric vs intestinal mucosal lipid peroxidation by superoxide generating system-6-9% vs 8-11%; gastric vs intestinal mucosal lipid peroxidation by hydroxyl radical generating system: 11-24% vs 15-27%). All these results indicate that LF may exhibit some scavenging ability towards hydroxyl radicals by chelating iron. Results on gastroprotective effects of LF treatment on alcohol induced lipid peroxidation in model rats have shown that only pretreatment of animals with LF (1 g/kg/day p.o in two equally divide doses 12 h apart) prevented oxidant injury by approximately 12% in both gastric and intestinal mucosa. No protective effects were produced from LF post-treatment in the mucosal lipid peroxidation in rats challenged with oxidant injury. Similarly pre-treatment protective effects of LF were noticed with respect to DNA fragmentation (6%) and membrane micro-viscosities (7%) in mucosal tissues. Based on the results from these studies it can be concluded that only pretreatment with LF offers protection against the deleterious effects of oxidant injury in gastrointestinal mucosa. It is also concluded that LF provides the protection against oxidant injury by chelating iron as seen from the comparative results with desferrioxamine.
We have investigated whether functions of pituitary gland change when the rats are exposed to sinusoidal magnetic fields at dark. In this study, 26 Wistar Albino rats were divided into two groups as experimental (n=14) and sham group (n=12). Experimental was exposed to 0.75 mT sinusoidal magnetic field procuded by Helmholtz coils and sham group was housed between inactivated Helmholtz coils, for one month. After one month Animals were sacrificed and their blood were taken. Serum hormone levels were determined by Radioimmunassay method. In exposed group, serum cortisol TSH, FSH and prolactin concentration did not statistically changed according to sham exposed group (p>0.05), but Growth Hormone and testesterone levels statistically changed (p<0.05).
Osteocalcin, also called bone gla-protein (BGP), is a small, vitamin D and vitamin K-dependent noncollagenous, calcium-binding protein synthesized by osteoblasts and odontoblasts (1-7). Presently, it is the only protein found to be specific for bone and dentin. Although the majority of synthesized osteocalcin associates with bone, a fraction of neosynthesized osteocalcin is released into the circulation (1,5,8). Serum osteocalcin is an important marker of bone turnover in normal subjects and patients (1,3,5). Current understanding of the role of osteocalcin based on radioimmunoassay measurements and there is considerable interest in its determination in serum as a noninvasive index of bone formation(1).
Skeletal alkaline phosphatase, an enzyme localised in the osteoblasts as well as in the extracellular layers of a newly synthesized matrix, is released into the circulation by an unclear mechanism. Serum alkaline phasphatase is derived from several sources including the liver, bone (where it is needed for osteoblastic activity), kidney, intestine, and placenta (in pregnant women). Therefore, elevated levels of serum alkaline phosphatase are observed in a variety of disorders such as rickets and osteomalacia, Paget's disease, hyperparathyroidism, during the healing of fractures, osteoblastic carcinoma and intra- and extrahepatic cholestasis. Serum total alkaline phosphatase activity is the most commonly used marker of bone formation, but it lacks sensitivity and specifity. Many assay procedures have been developed in attempts to improve the specifity and the sensitivity of serum alkaline phosphatase measurement. A new reagent which has recently been reported is likely to be available in the future.
The erythrocyte (RBC) deformability and lipid composition of RBC membrane were investigated in non-insulin dependent diabetes mellitus (NIDDM) patients (n=20) and healthy controls (n=15). The RBC deformability, whole blood and plasma viscocity were significantly higher in NIDDM patients than in controls (p<0.001). No difference in the RBC count and MCV were found between NIDDM patients and controls. Total cholesterol (TC), total phospholipid (TPL) levels of the plasma were significantly high (P<0.001) and no significant differences were observed in the levels of low density-cholesterol (LDL-C), and high density-cholesterol (HDL-C) in patients with NIDDM compared with the control group. In RBC, TC levels of NIDDM patients were found to be increased (P<0.001) when compared with controls. The levels of TPL did not change in RBC between NIDDM patients and controls. In the plasma and RBC, the ratio of TC/TPL was found to be increased in NIDDM patients compared with control group. A similar trend was observed for RBC phosphatidyicholine (PC) levels, but in this case, the increase was not statistical significantly. This finding shows that RBC deformability is regulated by lipid compositions of the cell membrane in the NIDDM patients. This regulation plays an important role between diabetes and vascular diseases.
Pleurotus sajor-caju, an edible mushroom was grown under submerged condition in whey medium. Different inorganic and organic nitrogen sources were added to deproteinized whey to study their effect on growth and protein content of P. sajor-caju. Increase in biomass production was noted with all the nitrogen sources tested except urea, which was inhibitory. Nitrogen sources showed marked influence on protein and ash content of the biomass, which varied from 29.2 to 39.1% and 15.1 to 19.1% respectively. Pollution load of whey could be reduced substantially by culturing P. sajor-caju in whey.
Protein synthesis during cerebral ischemia is blocked by energy failure and impaired after restoration of energy stores. The mechanisms of prolonged impairment of brain protein synthesis by transient ischemia are not fully understood,however, it seems that proteins may become more vulnerable to a persistant imbalance between synthesis and degredation or to different abnormalities after ischemia. To assess the effects of transient ischemia on specific proteins, rats are submitted to 20 min four-vessel occlusion (4VO) followed by recirculation times from 30 min to 7 days. The soluble supernatant and membrane fractions are obtained. Boiled soluble fractions are loaded onto a SDS-12.5% polyacrylamide gel electrophoresis. The separated proteins quantified with a densitometer. Changes of proteins are observed. The possibility that abnormal changes of proteins after ischemia may participate to the pathological process of ischemic disturbances is discussed.
