Search Results
Results 351 - 400 of 1653
< 3 4 5 6 7 8 9 10 11 12 13 >
Foster Richard H - - 2002
The present study was designed to assess the effect of okadaic acid (OA), a protein phosphatase inhibitor, on aldosterone secretion in response to angiotensin II (AII), adrenocorticotropin (ACTH) and rises in external potassium concentration (K+). AII (10nM) caused a 20-fold increase in aldosterone production and OA reduced this response by ...
Leira F - - 2002
Apoptotic changes induced by okadaic acid and yessotoxin in BE(2)-M17 neuroblastoma cells have been evaluated and quantified by combining classical methods and fast and sensitive fluorimetric microplate assays. The phosphatase inhibitor okadaic acid induced rapid time- and dose-dependent apoptotic changes in this cell line, which were evident after 1h at ...
Van Wambeke F - - 2002
The effect of phosphate (P), nitrate (N), and organic carbon (C, glucose) enrichment on heterotrophic bacterial production was examined along two longitudinal transects covering the whole Mediterranean Sea during June and September 1999. During these cruises, integrated bacterial production ranged from 11 to 349 mgC m(-2) d(-1) for the 0-150 ...
Carneiro-Santos P - - 2001
The fluorescent probe LysoTracker Red was used to examine for the presence of acidic vesicles in cercariae and schistosomula of Schistosoma mansoni. Acidic vesicles were widely distributed throughout the body of freshly transformed schistosomula and 24-h-old schistosomula but were absent from cercariae. The vesicles of freshly transformed schistosomula were undetectable ...
Ahlemeyer B - - 2001
The standardized extract from Ginkgo biloba (EGb 761) is used for the treatment of dementia. Because of allergenic and genotoxic effects, ginkgolic acids are restricted in EGb 761 to 5 ppm. The question arises whether ginkgolic acids also have neurotoxic effects. In the present study, ginkgolic acids caused death of ...
Conconi M T - - 2001
An inadequate protein intake seems to be involved in the pathogenesis of osteoporosis. Moreover, protein from animal sources appears to protect against hip fracture, while protein from vegetable sources, which present low levels of essential amino acids, has no effect. In this preliminary work, the growth, the alkaline phosphatase activity ...
Miyazaki S - - 2001
We cloned the human tartrate-resistant acid phosphatase (TRAP) gene from human osteosarcoma cells (Saos-2), and produced recombinant human TRAP (rhTRAP) using a baculovirus vector expression system. RhTRAP from Sf9 culture medium was purified by cation exchange chromatography, gel filtration and affinity chromatography. The molecular mass and amino acid composition of ...
Masuda T - - 2001
Hen egg lysozyme elicits a sweet taste sensation for human beings. Effects of reduction of disulfide bonds, heat treatment, and chemical modification of hen egg lysozyme on both sweetness and hydrolytic activity were investigated. Both the sweetness and enzymatic activities were lost when the intradisulfide linkage in a lysozyme molecule ...
Brambila E - - 2001
Ribonucleases (RNases) are a group of enzymes that hydrolyze different classes of RNA. It has been suggested that RNase activity in cells can act to indirectly regulate protein synthesis by controlling RNA degradation. However, little is known about the role of RNases under conditions characterized by a sudden increase of ...
Sodeoka M - - 2001
Selective inhibitors of protein tyrosine phosphatases (PTPs) and dual-specificity phosphatases (DSPs) are expected to be useful tools for clarifying the biological functions of the PTPs themselves and also to be candidates for novel therapeutics. We planned a library approach for the identification of PTP/DSP inhibitors in which 3-acyltetronic acid is ...
Kang H - - 2001
Protein phosphatase 5 (PP5) exhibits low basal activity due to the autoinhibitory properties of its N-terminal and C-terminal domains but can be activated approximately 40-fold in vitro by polyunsaturated fatty acids. To identify residues involved in regulating PP5 activity, we performed scanning mutagenesis of its N-terminal tetratricopeptide repeat (TPR) domain ...
Aoyama H - - 2001
The effects of two lectins concanavalin A (conA) and soybean agglutinin, on soybean seed acid phosphatase activity were investigated using p-nitrophenylphosphate (pNPP), pyrophosphate (PPi) and phosphoenolpyruvate (PEP) as substrates. Of the four acid phosphatase isoforms (AP1, AP2, AP3A and AP3B) purified from soybean seeds, only AP1 was activated 40 and ...
Collins K A - - 2001
The survival of spermatozoa and the persistence of prostatic acid phosphatase has been an area of interest for investigators of sexual assault. However, not much documentation exists concerning the examination of a deceased individual with regard to the postmortem interval and presence of such evidence. The authors reviewed cases referred ...
Uchida K - - 2001
Within developing ovaries of many insects, some developing follicles or oocytes usually degenerate (follicular atresia or oosorption), while the others may continue to grow to maturity, thus maintaining the balance between the number of eggs and reproductive circumstances such as available nutrients. To help clarify the phenomenon of follicular atresia ...
McCormick K M - - 2001
Transforming growth factor beta (TGFbeta) is secreted as a biologically inactive complex by many cell types in vitro, but little is known of TGFbeta's activation status in vivo. This study examined the in vivo expression of active and total (active + acid-activatable) TGFbeta2 in embryonic chicken hearts during cardiac morphogenesis ...
Verrelli B C - - 2001
Earlier studies of the common PGM allozymes in Drosophila melanogaster reported no in vitro activity differences. However, our study of nucleotide variation observed that PGM allozymes are a heterogeneous mixture of amino acid polymorphisms. In this study, we analyze 10 PGM protein haplotypes with respect to PGM activity, thermostability, and ...
Sisemore M F - - 2001
Leukotoxin, a cytochrome P450-derived epoxide of linoleic acid, has been implicated as a causative factor in acute respiratory distress syndrome. Conversion of this fatty acid epoxide to leukotoxin diol by epoxide hydrolase has been hypothesized as the critical activation step in leukotoxin-induced cellular toxicity. In both human and insect cells, ...
Hegeman C E - - 2001
Phytic acid (myo-inositol hexakisphosphate) is the major storage form of phosphorus in plant seeds. During germination, stored reserves are used as a source of nutrients by the plant seedling. Phytic acid is degraded by the activity of phytases to yield inositol and free phosphate. Due to the lack of phytases ...
Zhang J M - - 2001
To investigate the neurologic mechanisms of acidic local anesthetic-induced low back pain in humans, we administered bupivacaine and buffered saline at acidic or alkalinized pH at the L5 dorsal root ganglion (DRG) of rats via a hole drilled through the transverse process covering the DRG. Behavioral changes were tested before ...
Partanen S - - 2001
The effect of pH during formalin fixation on acid phosphatases in human tissues was studied. Lysosomal-type acid phosphatase was sensitive to alkaline fixation, being completely inactive after fixation at pH 9.0. Prostatic and tartrate-resistant osteoclastic/macrophagic types were alkaline fixation-resistant, as was an acid phosphatase localized in endothelium, endometrial stromal cells ...
Goto T - - 2001
The serum acid phosphatase value was examined in nine patients with giant cell tumour of bone. Five showed a high level of acid phosphatase, which fell to within normal limits after surgery. Although the remaining four patients showed a normal acid phosphatase level before surgery, the postoperative acid phosphatase level ...
Centeno C - - 2001
Two assays were conducted to study the evolution of rye and barley phosphatases (phytase and acid phosphatase) and the degradation of its substrates (inositol phosphate esters) during seed germination. In this manner we could obtain a low-phytate, endogenous phosphatase rich ingredient to be used in animal nutrition. In the first ...
Stewart B R - - 2001
There is great interest in returning coal combustion products to mining sites for beneficial reuse as liming agents. A column study examined the effects of blending two coal fly ashes with an acid-forming coal refuse (4% pyritic S). Both fly ashes were net alkaline, but had relatively low neutralizing capacities. ...
Mistry S J - - 2001
Stathmin is a microtubule-destabilizing phosphoprotein that plays a critical role in the regulation of mitosis. The microtubule-depolymerizing activity of stathmin is lost upon phosphorylation in mitosis. Although the role of phosphorylation of stathmin by p34(cdc2) kinase in the assembly of the mitotic spindle is well established, the role of dephosphorylation ...
Igarashi Y - - 2001
The objective of the present study was to develop a specific method for the separation of tartrate-resistant acid phosphatase (TRAP) derived exclusively from osteoclasts. Heparin column-bound TRAP in human serum was separated into three peaks of TRAP activity when eluted with a linear gradient of sodium chloride. The last peak ...
Park H - - 2001
A previously undescribed cyclic heptapeptide hepatotoxin was isolated from a cyanobacteria waterbloom collected in Pakowki Lake, Alberta, Canada (49 degrees 20'N and 110 degrees 55'W). The compound was characterized by amino acid analysis, ESIMS/CID/MS, (1)H and (13)C NMR, and UV spectroscopy. Structure of the new microcystin was assigned as [D-Leu(1)]microcystin-LR ...
Leira F - - 2001
We have studied different biochemical indicators of apoptosis in okadaic acid-treated normal human lung fibroblasts (NHLF). Apoptosis was identified by fluorimetric microplate measurements of DNA content, caspase-3 activation and changes in mitochondrial and plasma membrane after 1-48-h treatments with 1-1000 nM okadaic acid. Cells exposed to okadaic acid showed activation ...
Souto M L - - 2001
Okadaic acid (OA) (1)) was the first example of a group of polyether toxins known to be produced by marine microalgae, which are responsible for the natural phenomena known as Diarrhetic Shellfish Poisoning (DSP) red tides. It is also a highly selective inhibitor of protein phosphatases type 1 (PP1) and ...
Moreno F J - - 2001
The heterogeneity of caprine caseinmacropeptide (CMP) was determined by means of treatments with neuraminidase and acid phosphatase and analyses by anion exchange FPLC and reversed-phase (RP)-HPLC, with on-line and off-line electrospray ionization mass spectrometry. The main CMP components were two non-glycosylated and di-phosphorylated forms, as well as two other mono-phosphorylated ...
Frydrychowski V A - - 2001
Okadaic acid is a potent inhibitor of select serine/threonine protein phosphatases. The importance of the C28-C38 hydrophobic domain of okadaic acid for inhibition of PP1 and PP2A was investigated. The hydrophobic domain is required but not sufficient for potent inhibition, and it also contributes to differential inhibition between PP1 and ...
Wiley J P - - 2001
Phenylboronic acid bioconjugates prepared from alkaline phosphatase by reaction with either 2,5-dioxopyrrolidinyl 3-[N-[3-(1,3,2-dioxaboran-2-yl)phenyl]carbamoyl]propanoate (PBA-XX-NHS) or 2,5-dioxopyrrolidinyl 6-[[3,5-di-(1,3,2-dioxaboran-2-yl)phenyl]carbonylamino]hexanoate (PDBA-X-NHS) were compared with respect to the efficiency with which they were immobilized on salicylhydroxamic acid-modified Sepharose (SHA-X-Sepharose) by boronic acid complex formation. When immobilized on moderate capacity SHA-X-Sepharose (5.4 micromol of SHA/mL ...
Bem S - - 2001
The solution structure and thermal stability of human prostatic acid phosphatase (hPAP) in the absence and in the presence of tartaric acid were studied by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The temperature dependence of the infrared spectrum and DSC scans indicate that hPAP undergoes thermal ...
Aragon V - - 2001
Legionella pneumophila is an intracellular pathogen of protozoa and alveolar macrophages. This bacterium contains a gene (pilD) that is involved in both type IV pilus biogenesis and type II protein secretion. We previously demonstrated that the PilD prepilin peptidase is crucial for intracellular infection by L. pneumophila and that the ...
Pan H J - - 2000
In order to understand virulence factors of Chryseobacterium indologenes isolates associated with invasive infection, enzymatic activities and cellular fatty acid profiles of 42 isolates recovered at National Taiwan University Hospital from January 1994 to December 1996 were studied. Among them, 12 blood isolates were considered as invasive and 30 (recovered ...
Saleh M T - - 2000
Mycobacterium tuberculosis secretes a large number of polypeptides with broad biological and immunological functions. We describe here the characterization of a 28-kDa acid phosphatase of M. tuberculosis (SapM) localized to the culture filtrate. The mature protein demonstrated biochemical characteristics similar to those of the bacterial nonspecific acid phosphatases. However, SapM ...
Edqvist J - - 2000
In Euphorbia lagascae the major fatty acid in triacylglycerol is the epoxidated fatty acid vernolic acid (cis-12-epoxyoctadeca-cis-9-enoic acid). The enzymic reactions occurring during the catabolism of epoxidated fatty acids during germination are not known, but it seems likely that the degradation requires the activity of an epoxide hydrolase. Epoxide hydrolases ...
Aleksieva P - - 2000
The feasibility of using proteinase producing fungus Humicola lutea 120-5 as a source of extracellular acid phosphatase was investigated. To enhance the acid phosphatase yield and significantly reduce the proteolytic activity the composition of casein-glucose medium containing inorganic phosphate (Pi) was modified. The regulation of phosphatase formation was controlled by ...
Bedet C - - 2000
gamma-Aminobutyric acid (GABA) and glycine are stored into synaptic vesicles by a recently identified vesicular inhibitory amino acid transporter [VIAAT, also called vesicular GABA transporter (VGAT)]. Immunoblotting analysis revealed that rat brain VIAAT migrated as a doublet during sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with a predominant slower band in all ...
Fernandes A P - - 2000
Beside the morphofunctional modifications undergone during spermiogenesis, the spermatozoon could undergo other modifications after copulation. Since no structural modification occurs in the spermatozoon of Acrosternum aseadum after copulation, we used cytochemical studies to show the enzymatic activities variations of acid phosphatase, thiamine pyrophosphatase, glucose-6-phosphatase and cytochrome C oxidase, when the ...
Hamilton A - - 2000
Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus ...
Kalamidas S A - - 2000
Glycogen autophagy in newborn rat hepatocytes was studied by using enzyme determinations and electron microscopy. Cyclic AMP induced glycogen autophagy in these cells. Glycogen-hydrolyzing acid glucosidase activity increased whereas acid mannose 6-phosphatase activity decreased in the liver of these animals. Parenteral glucose, which prevents postnatal glucagon secretion and tissue cyclic ...
Zippel H P - - 2000
Goldfish are ideal vertebrates for the study of regeneration within the peripheral and the central olfactory system. The present behavioural investigations studied the effects of bilateral lesions on the animals' ability to qualitatively discriminate two amino acids (10(-6) M) and their performance in two more difficult tasks: (i) rewarded amino ...
Kim J Y - - 2000
The expression of invertases was analyzed in vegetative organs of well-watered and water-stressed maize (Zea mays) plants. Early changes in sucrose metabolism and in acid soluble invertase expression were observed in vegetative sink and source organs under mild water stress. The organ-specific induction of acid invertase activity was correlated with ...
Tsekova K - - 2000
Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper were compared to three copper-sensitive Rhizopus species. High level of acid phosphatases and decreased Cu2+-uptake were found with resistant in contrast to sensitive strains. The presence of copper(II) ions in the medium increased the production of acid phosphatases ...
Uma B - - 2000
The basic phospholipase A(2) (VRV-PL-VIIIa) from Vipera russelli venom induces multiple toxic effects including neurotoxicity, myotoxicity, edema and hemorrhage. This phospholipase A(2) has been extensively characterized for its pharmacological properties except for hemorrhagic activity. In the present investigation, the lung hemorrhagic activity was assayed using lung dye diffusion method. The ...
Kato T - - 2000
A new analytical method for the detection of bile acids has been developed by adopting an alkaline phosphatase-linked DNA oligomer that binds to bile acids. A 5'-biotin-labeled DNA oligomer with a 40-nucleotide length that is defined by the in vitro selection method was connected with alkaline phosphatase through an avidin-biotin ...
Yang X - - 2000
Incubation of opossum kidney clone P (OKP) cells in acid media (pH 6. 8) causes activation of Na(+)/H(+) exchanger 3 (NHE3) at 6, 12, and 24 h. OKP cell NHE3 protein abundance was increased by 45% at 24 h of acid incubation but was unaffected at 3-12 h. By contrast, ...
Ten-Hage L - - 2000
Okadaic acid was isolated from a strain of Prorocentrum arenarium Faust (Prorocentrales, Dinophyceae) collected from Europa Island (40 degrees 22'E, 22 degrees 20'S, SW Indian Ocean). The presence of okadaic acid in the algal extract was suspected after cytotoxicity and phosphatase 2A inhibition testing. It was confirmed by ADAM derivatization, ...
Mehvar R - - 2000
A macromolecular prodrug of methylprednisolone (MP) was synthesized by conjugating MP with dextran with a M(W) of 70000 through a succinic acid linker. It has been shown previously that the dextran-MP conjugate (DMP) releases MP directly or indirectly through formation of methylprednisolone succinate (MPS) which is further hydrolyzed to MP. ...
Mandala S M - - 2000
Sphingosine and sphingosine-1-phosphate (SPP) are interconvertible sphingolipid metabolites with opposing effects on cell growth and apoptosis. Based on sequence homology with LBP1, a lipid phosphohydrolase that regulates the levels of phosphorylated sphingoid bases in yeast, we report here the cloning, identification, and characterization of a mammalian SPP phosphatase (mSPP1). This ...
< 3 4 5 6 7 8 9 10 11 12 13 >