Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009443 (cold)
 92,137 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this study was to evaluate the effect of prostaglandin E1 (PGE1) on protecting against hepatic endothelial cell damage and increasing graft viability after cold preservation and reperfusion, using an isolated perfused rat liver (IPRL) model. The grafts were divided into three groups, according to the cold preservation time and PGE1 administration, namely: 4h preservation (group 1, n = 9), 6h preservation (group 2, n = 9), and 6h preservation followed by PGE1 infusion (group 3, n = 9). After cold storage, the grafts were put on the recirculating IPRL system, then reperfused for 120 min at 37 degrees C with oxygenated Krebs-Henseleit buffer containing hyaluronic acid (HA). To examine the function of the sinusoidal endothelial cells and hepatocytes, serial measurements of HA, tumor necrosis factor-alpha (TNFalpha), thromboxane B2 (TXB2), acid phosphatase, and conventional parameters in the perfusate were made. After perfusion, the trypan blue exclusion test was performed to assess the presence of any microscopic sinusoidal lining cell damage. In group 3, the bile output and HA clearance were significantly greater, while glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, TNFalpha, TXB2, and acid phosphatase in the perfusate were significantly lower than in group 2. Histologically, less endothelial cell damage and hepatocyte damage than in group 2 was also confirmed. These results therefore suggest that the improvement of hepatic graft viability by PGE1 administration is mainly due to sinusoidal endothelial cell protection.
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PMID:The mechanism of hepatic graft protection against reperfusion injury by prostaglandin E1. 1038 67

Celsior, a low viscosity and low potassium preservation solution, has recently been tested successfully in the cold preservation of heart, lung, kidney and small intestine. The purpose of the present study was to evaluate the potential of Celsior in the cold preservation of the liver. Livers were harvested from male Wistar rats and then flushed with either Celsior (CE), University of Wisconsin solution (UW) or histidine-tryptophan-alpha-ketoglutarate solution (HTK) and stored for 24 h at 4 degrees C in the respective solution. The reperfusion was performed in vitro using a recirculating model with oxygenated (95% O(2), 5% CO(2)) Krebs-Henseleit buffer at 37 degrees C. To simulate the slow rewarming during the surgical implantation in vivo, all livers were stored for 30 min at room temperature prior to reperfusion. After ischemic storage and also after reperfusion some samples were freeze-clamped for analysis of tissue metabolites while others were tested for structural and functional integrity by the isolated perfusion. CE vs. UW vs. HTK: Metabolic preservation of tissue ATP (micromol/g dry weight) during cold storage was best with Celsior (0. 46 +/- 0.17 vs. 0.26 +/- 0.03 vs. 0.35 +/- 0.07; p < 0.05 CE vs. UW), but upon reperfusion energetic recovery was comparable in the three groups (3.45 +/- 0.66 vs. 4.27 +/- 0.41 vs. 3.63 +/- 0.64 micromol/g/dry weight). There appeared to be structural integrity during reoxygenation irrespective of the used preservation solution with comparable values of parenchymal enzyme release (ALT: 575 +/- 82 vs. 547 +/- 106 vs. 593 +/- 38 mU/g/l), bile production (18.0 +/- 1.0 vs. 18.5 +/- 2.5 vs. 18.7 +/- 1.4 microl/g/ min), and the release of acid phosphatase, an indicator for activated Kupffer cells (89 +/- 13 vs. 90 +/- 5 vs. 123 +/- 21 mU/g/l) in this in vitro model. Vascular flow characteristics were approximated by the portal perfusion pressure, which tended to be elevated upon initial reperfusion in the UW group (8.4 +/- 0.6 mm Hg) compared to 6.6 +/- 1.0 and 7.3 +/- 0.4 mm Hg in Celsior and HTK, respectively. However, the pressure values decreased to the normal range even in the UW group with ongoing perfusion. The sensitivity of our model in detecting protective effects of the tested solution was confirmed by a negative control group of livers stored in Ringer's solution at 4 degrees C, yielding an impaired recovery which differed by one magnitude from the three other groups. Within the limits of an in vitro study it is concluded from these results that Celsior may become a suitable alternative for liver preservation and further studies including a transplantation in vivo are strongly encouraged.
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PMID:Experimental liver preservation with Celsior: a novel alternative to University of Wisconsin and histidine-tryptophan-alpha-ketoglutarate solutions? 1087 54

Human gammadelta T lymphocytes play an important role in nonadaptive reactions to infection and early tumor defense. This is the first report that freshly isolated, native gammadelta T cells of some healthy donors can kill human neuroblastoma cells to varying degrees. Their killing ability was increased and maintained during expansion and cultivation with interleukin-2 (IL-2; 400 IU/mL) for as long as 30 days (100% specific lysis at an effector-to-target cell (E:T) ratio of 20:1). gammadelta T lymphocytes without this spontaneous killing ability gained a specific cytolytic activity of 81% +/- 10.4% SD after stimulation with IL-2 for 24 hours. gammadelta cells were isolated from peripheral blood by positive enrichment (using a magnetic cell sorting system; purity, 95.2% +/- 3.2% SD, n = 21). High natural cytotoxic activity against human neuroblastoma cell lines (>50% specific lysis at an E:T ratio of 20:1) was exhibited by one of 11 donors, whereas two of 11 showed medium cytotoxicity (30% to 50% specific lysis). Eight of 11 donors showed very slight or no lytic activity against human neuroblastoma cells (<30% specific lysis). gammadelta T cells were also cytotoxic against Daudi (32.7% specific lysis at an E:T ratio of 20:1), Raji (10.3%), Colo 205 (23.1%), A 204 (54%), K 562 (100%), and SK-N-MC (100%) cells. Isolated gammadelta T cells were grown in Iscove modified Dulbecco medium with IL-2 (400 IU/mL). Increased cell proliferation (38.5% to 182%) was induced with phytohemagglutinin, IL-15, Clodronat, OKT3, or various combinations of these. Results of cold target inhibition assays suggest a natural killer-like activity of the gammadelta T-cell killing mechanism. Peptidase or papain render neuroblastoma cells unsusceptible to gammadelta T-cell killing, suggesting the involvement of antigen peptide(s) in the process of neuroblastoma cell killing. Treatment with acid phosphatase reduced specific lysis by 66.5% +/- 34.1% SD, which suggests a binding to phosphorylated neuroblastoma cell-surface structures in the killing mechanism of gammadelta T cells. Heat shock did not affect the extent of neuroblastoma killing by gammadelta cells. Recognition of neuroblastoma cells by gammadelta cytotoxic T lymphocytes is negatively regulated by major histocompatibility complex I receptors. Evidence for natural and inducible cell cytotoxicity of gammadelta T cells against human neuroblastoma cells, easy propagation, purification, and missing alloreactivity in mixed lymphocytes cultures indicates a role for this subpopulation of T lymphocytes in adoptive immunotherapy.
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PMID:Human gammadelta T lymphocytes exert natural and IL-2-induced cytotoxicity to neuroblastoma cells. 1100 47

An Antarctic marine bacterium (strain 116) excreting an extracellular cold-adapted metalloprotease was subjected to a detailed polyphasic taxonomic investigation. Strain 116 was previously isolated from the stomach of a specimen of the Antarctic krill Euphasia superba Dana and tentatively characterized as Sphingomonas paucimobilis 116. The 16S rDNA sequence analysis showed that the strain is in fact related to species of the genus Psychrobacter, next to Psychrobacter glacincola (97.4% similarity). Sequence similarities between strain 116 and other Psychrobacter species ranged from 96.9% (with P. urativorans) to 95.4% (with P. immobilis). Key phenotypic characteristics as well as chemotaxonomic features of the bacterium were congruent with the description of the genus Psychrobacter i.e. cells were strictly aerobic, strongly oxidase-positive, psychrotrophic, halotolerant, gram-negative non-motile coccobacilli, with ubiquinone-8 as the main respiratory lipoquinone and 18:1 cis 9, 16:1 cis and 17:1 (omega8c being the predominant cellular fatty acids. The G+C content of the DNA was 43.6 mol%. DNA-DNA hybridization studies showed that the relatedness between strain 116 and Psychrobacter glacinola is only 62.2%. Further differences were apparent in whole-cell SDS-PAGE protein pattern, cellular fatty acid profile and in a number of physiological and biochemical characteristics as well as in enzymatic activities. Tolerance to 5% bile salts, nitrate reduction, citrate utilization, acid production from carbohydrates, alkaline phosphatase, acid phosphatase, C4 esterase, C14 lipase and valine arylamidase were found to differentiate strain 116 from Psychrobacter glacincola. On the basis of this phenotypic and molecular evidences, strain 116, previously known as Sphingomonas paucimobilis 116, was recognized as a new species of the genus Psychrobacter for which the name Psychrobacter proteolyticus is proposed. Strain 116 has been deposited in the Collection de l'Institut Pasteur, France, as CIP106830T and in the Deutsche Sammlung von Mikroorganismen and Zellkulturen, as DSM13887.
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PMID:Psychrobacter proteolyticus sp. nov., a psychrotrophic, halotolerant bacterium isolated from the Antarctic krill Euphausia superba Dana, excreting a cold-adapted metalloprotease. 1140 98

Three hundred fifty newborns from Rome and 351 from Penne were studied in continental Italy. Medium high altitude above sea level and cold winters characterize the area of Penne, while low altitude and very mild winters characterize the area of Rome. An effect of environmental conditions on the association between adenosine deaminase (ADA) and acid phosphatase (ACP1), previously shown in Sardinia, has been confirmed in continental Italy. When compared with expected independent assortment, the proportion of ACP1*A/*A carrying the ADA*2 allele is lower than expected in the lowlands and higher than expected in highlands. In continental Italy there is an interaction among ACP1-ADA genotype, season of conception, and locality. The excess of *A/*A newborns carrying the ADA*2 allele is present only among those conceived in the first half of the year (January-June). Among newborns in Penne conceived in the Spring, the proportion of those with *A/*A genotype is increased and these infants show decreased intrauterine growth. The present data suggest that ADA and ACP1 interact during intrauterine life with effects on development and survival and that such effects are dependent on local environment and season of conception. Am. J. Hum. Biol. 12:214-220, 2000. Copyright 2000 Wiley-Liss, Inc.
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PMID:Adenosine deaminase-acid phosphatase association and the environment: A study in a continental Italian population. 1153 18

The acid phosphatase locus 1 (ACP1) codes for a low molecular weight phosphotyrosine protein phosphatase that has the important action of dephosphorylating tyrosine phosphorylated proteins and peptides and a second important role in modulating flavin cofactor levels and the activity of flavo-enzymes. These functions significantly influence cell division, differentiation, and growth. Two alleles (ACP1*A and ACP1*B) reach polymorphic frequencies at the ACP1 locus in all human populations, while the ACP1*C and ACP1*R alleles reach polymorphic frequencies in restricted geographical regions. The worldwide distribution of these alleles, and data from several clinical studies, strongly suggest that the ACP1 locus functions to modulate growth and that selection at this locus is a component of the selective processes influencing body mass and human population adaptation to thermal stress. The ACP1*A allele reaches highest frequencies at extreme latitudes and appears to be associated with maximizing body mass and adaptation to cold stress, whereas the ACP1*B allele reaches highest frequencies in tropical and subtropical environments and appears to be associated with minimizing body mass and adaptation to heat stress. The high frequency of the ACP1*C allele at northern latitudes, where ACP1*A allele frequencies are elevated, may be a mechanism for limiting fetal and maternal complications associated with fetal macrosomia and adult obesity in populations where protein and calorie intake are relatively high. Am. J. Hum. Biol. 12:688-701, 2000. Copyright 2000 Wiley-Liss, Inc.
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PMID:Acid phosphatase locus 1 (ACP1): Possible relationship of allelic variation to body size and human population adaptation to thermal stress-A theoretical perspective. 1153 62

In order to obtain some informations on the nature and relative activity of the phosphatases present in various helminths, biochemical studies have been made in thirteen kinds of worm parasites including the adults and larvae (Fasciola hepatica, Eurytrema pancreaticum, Paramphistomum sp., Taenia solium, Taenia pisiformis, Dipylidium caninum, Diphyllobothrium mansoni, Cysticercus cellulosae, Cysticercus fasciolaris and Sparganum). A comparison based on the analysis of pH-activity curves was made among these helminths. The worm materials were mostly obtained alive from an abattoir and removed from the organs or tissues of the animal hosts naturally infected. Sparganum and Cysticercus cellulosae, however, are collected from the subcutaneous tissue of the patients by surgical removal. The worms thoroughly washed were weighed and transferred with 0.1 M Tris buffer to a chilled glass grinder (Capacity; 15 ml) and homogenized in the cold. The homogenate was centrifuged at 5000 RPM for 30 minutes. The supernatant was pipetted off for determination of the phosphatase activity. Incubation mixtures consisted of 1 ml substrate, 1 ml buffer and 0.5ml extract. The buffers used were Tris (Hydroxymethyl) aminomethane and citric acid monohydrate and the substrate was paranitrophenyl phosphate (1 gm/25 ml). These mixtures were incubated at the temperature of 37 degrees C for 30 minutes in water bath. The absorbance or transferance of mixture was determined colorimetrically by "Spectronic 20 "spectrophotometer at 410 nm against a distilled water blank. The amount of phenol liberated was then calculated from a standard curve using phenol solutions. Controls consisted of unincubated mixtures. The results were deducted from this experiment. The phosphatase activity occurred over all parasitic helminths used in this experiment. In trematodes, pH-activity curves have demonstrated two peaks of phosphatase activity in Fasciola hepatica and Paramphistomum species. However the acid phosphatase activity was predominantly found and the alkaline phosphatase activity was found distinctly to be low in all three species. In Eurytrema pancreaticum, the pH-activity curves displayed two peaks in acid phosphatase activity, one at pH 5.0 and the other pH 9.0. In cestodes, both alkaline and acid phosphatase activity displayed the pH optima 5.0 and 9.0 to 10.0 in the adult tapeworms. However, major activity in the adults is due to the alkaline phosphtases. In contrast to the adults, Cysticercus and sparganum showed the higher activity in acid phosphatases which predominates in the larvae. In all cases of nematodes, the pH optimum for acid phosphatase was 4.0 to 6.0. A preponderance of acid phosphatase activity was shown in the extract of intestine of Ascaris lumbricoides. The aspect that phosphatases are correlated with phosphorylated passage of substances through the cuticle of helminths and may also be involved in carbohydrate metabolism is discussed.
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PMID:[Studies On Phosphatase Activity In Some Parasitic Helminths] 1291 52

Samples of liver from untreated rats, from rats infused with unconjugated bilirubin, and from biopsies of human liver were fixed overnight in cold formol-calcium. Frozen sections were stained for acid phosphatase activity by the Gomori lead-glycerophosphate procedure. Small blocks of fixed tissue were also incubated in this medium. These were then treated briefly with osmium tetroxide, dehydrated, and embedded in methacrylate. Thin sections were studied by electron microscopy. The sites of reaction product of acid phosphatase activity as visualized in electron micrographs are consistent with those seen in frozen sections studied by light microscopy. They indicate that the pericanalicular bodies of parenchymatous cells, the large spherical bodies of Kupffer cells, the microbodies appearing after bilirubin infusion and lipofuscin granules belong to the class of cytoplasmic organelles called lysosomes by de Duve.
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PMID:Localization of acid phosphatase activity in hepatic lysosomes by means of electron microscopy. 1369 27

THE ALDEHYDES INTRODUCED IN THIS PAPER AND THE MORE APPROPRIATE CONCENTRATIONS FOR THEIR GENERAL USE AS FIXATIVES ARE: 4 to 6.5 per cent glutaraldehyde, 4 per cent glyoxal, 12.5 per cent hydroxyadipaldehyde, 10 per cent crotonaldehyde, 5 per cent pyruvic aldehyde, 10 per cent acetaldehyde, and 5 per cent methacrolein. These were prepared as cacodylate- or phosphate-buffered solutions (0.1 to 0.2 M, pH 6.5 to 7.6) that, with the exception of glutaraldehyde, contained sucrose (0.22 to 0.55 M). After fixation of from 0.5 hour to 24 hours, the blocks were stored in cold (4 degrees C) buffer (0.1 M) plus sucrose (0.22 M). This material was used for enzyme histochemistry, for electron microscopy (both with and without a second fixation with 1 or 2 per cent osmium tetroxide) after Epon embedding, and for the combination of the two techniques. After fixation in aldehyde, membranous differentiations of the cell were not apparent and the nuclear structure differed from that commonly observed with osmium tetroxide. A postfixation in osmium tetroxide, even after long periods of storage, developed an image that-notable in the case of glutaraldehyde-was largely indistinguishable from that of tissues fixed under optimal conditions with osmium tetroxide alone. Aliesterase, acetylcholinesterase, alkaline phosphatase, acid phosphatase, 5-nucleotidase, adenosine triphosphatase, and DPNH and TPNH diaphorase activities were demonstrable histochemically after most of the fixatives. Cytochrome oxidase, succinic dehydrogenase, and glucose-6-phosphatase were retained after hydroxyaldipaldehyde and, to a lesser extent, after glyoxal fixation. The final product of the activity of several of the above-mentioned enzymes was localized in relation to the fine structure. For this purpose the double fixation procedure was used, selecting in each case the appropriate aldehyde.
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PMID:Cytochemistry and electron microscopy. The preservation of cellular ultrastructure and enzymatic activity by aldehyde fixation. 1397 66

Weimberg, Ralph (Northern Regional Research Laboratory, Peoria, Ill.), and William L. Orton. Synthesis and breakdown of the polyphosphate fraction and acid phosphomonoesterase of Saccharomyces mellis and their locations in the cell. J. Bacteriol. 89:740-747. 1965.-The conditions for accumulation of polyphosphate in cells of Saccharomyces mellis differ in several respects from those for acid phosphomonoesterase biosynthesis and maintenance. Polyphosphate can be synthesized or degraded in vivo by resting cells, provided an energy source is present. Experiments with growing cells indicate that the enzyme systems involved in the metabolism of the polyphosphate fraction are constitutive, since cells respond immediately to changes in the level of inorganic phosphate in the external medium. There is no change in the acid phosphatase level in either resting cells or in cells in the lag phase of growth. Enzyme formation or breakdown occurs only in cells that are exponentially dividing. Enzyme is lost rapidly from derepressed cells when they are transferred to a phosphate-rich medium, falling to a very low value by the time the cell mass had doubled. Protoplasts of repressed cells were prepared to determine the location of ortho- and polyphosphates in the cell. Previous studies have shown that phosphomonoesterase is released as a soluble enzyme when derepressed cells become protoplasts. Unlike phosphomonoesterase in derepressed cells, the two phosphate fractions in repressed cells are still attached to the protoplast after the cell wall has been digested and are eluted only when the protoplast structure is lysed in cold water. However, it is also possible to extract a part of the two phosphate fractions from intact cells in the absence of snail gut extract by osmotic shock if the cells are first suspended in a solution of high salt concentration. This treatment with salt does not affect viability. These results do not permit a definite conclusion concerning the location of ortho- and polyphosphates in the cell, other than that they are associated with the protoplast and thus occupy a position different from that of the phosphomonoesterase.
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PMID:SYNTHESIS AND BREAKDOWN OF THE POLYPHOSPHATE FRACTION AND ACID PHOSPHOMONOESTERASE OF SACCHAROMYCES MELLIS AND THEIR LOCATIONS IN THE CELL. 1427 55


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