bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Temperature on Initial Feeding in Alevins of Chinook Salmon (Oncorhynchus tshawytscha)
Authors: Heming T. A. , McInerney J. E. , Alderdice D. F.
Published: April 2009

Growth and survival of chinook salmon (Oncorhynchus tshawytscha) during the transition to active feeding were examined in relation to the timing of initial food presentation at 6, 8, 10, and 12 °C. The transition to active feeding in these salmon involved a period of "precocious feeding" during which ingestion of food had no effect on fish size, growth rate, or survival. Initial utilization of food for growth and survival did not coincide with any specific stage of development, but rather it occurred earlier and at a less mature stage of development at higher temperatures. Delays in initial food presentation beyond this point reduced fish size and survival. Temperature and the timing of initial food presentation interacted to create a zone of optimum feeding. Biomass production was maximized when alevins began to feed within this zone, independent of the precise time of initial food presentation or temperature. This optimum feeding zone existed at temperatures below 12 °C, between 905 thermal units (tu) postfertilization and a point (F, tu) which varied with temperature (T, °C) as F = 1201.1 − 20.3 T.Key words: temperature, initial feeding, Oncorhynchus tshawytscha, fish culture
Ingestion-Limited Growth of Aquatic Animals: The Case for Blackman Kinetics
Authors: Condrey Richard E.
Published: April 2009

The published data on ingestion-limited growth in aquatic animals is shown to be consistent with Blackman kinetics. As such, if ingestion limits growth rate there is a linear relationship between growth and ingestion from starvation to satiation. If, however, growth is limited by some factor other than ingestion rate, there is no increase in growth rate with increasing ingestion rate.Key words: ingestion, growth, growth efficiency, Blackman kinetics
Hepatic Metallothionein in Rainbow Trout (Salmo gairdneri) as an Indicator of Metal Pollution in the Campbell River System
Authors: Roch M. , McCarter J. A. , Matheson A. T. , Clark M. J. R. , Olafson R. W.
Published: April 2009

Hepatic metallothionein was measured in livers of freshly killed rainbow trout (Salmo gairdneri) using differential pulse polarography. The fish were caught in metal-contaminated lakes of the Campbell River watershed and in a nearby control lake. The livers were analyzed for zinc, copper, and cadmium using atomic absorption spectrophotometry. High and low molecular weight protein fractions were separated by gel chromatography from liver cytosols and analyzed for metals. A downward trend from the most contaminated lake to the least was found in levels of zinc in the water, of cadmium and copper in high molecular weight fractions, and of copper in low molecular weight fractions and metallothionein. The concentration of metallothionein is a useful quantitative measure of the degree of exposure of fish to heavy metals.Key words: metallothionein, rainbow trout, Salmo gairdneri; heavy metal pollution, sublethal exposures, mine wastes
Comparison of Searching Behavior for Zooplankton in an Obligate Planktivore, Blueback Herring (Alosa aestivalis) and a Facultative Planktivore, Bluegill (Lepomis machrochirus)
Authors: Janssen John
Published: April 2009

Studies of zooplankton feeding by juvenile blueback herring (Alosa aestivalis), an obligate planktivore, and juvenile bluegills (Lepomis macrochirus), a facultative planktivore, indicate that they search by markedly different methods. The herring searches as it swims, sighting most prey above its horizontal course, and swims up to take the prey. The bluegill searches while stopped (hovering). If a prey is sighted, it swims to it, sucks it in, then coasts to a stop to resume searching. If no prey is sighted, it swims a short distance, coasts to a stop, and searches again. For uniform size prey (Artemia salina first instar nauplii) the time the bluegill hovers in a particular search position is positively correlated with the distance the prey is from the fish (r2 = 0.69–0.77, four fish). This, in conjunction with previous work on bluegills, suggests they take the first prey item seen, rather than choosing between prey. The bluegill is more reactive to moving prey of Daphnia size; however, blueback herring do not distinguish between motile and nonmotile prey, perhaps because any prey's image is moving across its retina as the herring swims. Stopping to search may be adaptive where there is a heterogenous (weedy) background, whereas moving prey are detected against the stationary background. Such a background is likely confusing to a moving fish.Key words: blueback herring, Alosa aestivalis; bluegiil, Lepomis macrochirus; predation, zooplankton
Meristic variation in beaked redfishes, Sebastes mentella and S. fasciatus, in the Northwest Atlantic
Authors: Ni I-H.
Published: April 2009

The distribution of Northwest Atlantic beaked redfishes, Sebastes mentella and S. fasciatus, has been confused for the past several decades. Sebastes fasciatus has been reported as having lower meristic counts than S. mentella. Meristic elements of 33 301 vertebrae, 22 622 anal fin ray, and 16 290 dorsal fin ray counts were utilized to examine the yearly, depth, and geographic variation of meristics in beaked redfishes. Data collected from specimens caught off West Greenland, Baffin Island, Labrador, Newfoundland, Quebec, and Nova Scotia were analyzed by 100-m-depth intervals. Temporal and depth variation were examined by the χ2-test of independence on meristic frequencies. Geographic variation was evaluated using the modes and mean values in the meristic frequency histograms. Cluster analysis of meristic frequencies displayed the dendrographic affinities and the distance matrix among division–depth blocks.Temporal variation indicated a mixture of vertebral frequency patterns which varied with depth and area. Depth variation and geographic clines were found for each of these meristic characters; the shallow and southern waters were dominated by counts of 29, 14–13, and 7 for vertebrae, dorsal fin rays, and anal fin rays, respectively, whereas deep and northern waters were dominated by 30, 15–14, and 8–9. These results suggested that S. fasciatus occurs on the Nova Scotian Shelf and Grand Bank whereas S. mentella is largely found in Baffin Bay, Labrador waters, and the Gulf of St. Lawrence. The common names of S. mentella and S. fasciatus are discussed. Additionally, five hypothetical stocks of beaked redfishes based on meristic patterns are proposed for management purposes.Key words: Sebastes mentela, S. fasciatus, redfish, meristic variation, distribution, cluster analysis
Characteristics and Identification of Pasteurella and Vibrio Species Pathogenic to Fishes using API-20E (Analytab Products) Multitube Test Strips
Authors: Kent Michael L.
Published: April 2009

Morphological, cultural, and biochemical characteristics of Pasteurella spp. and Vibrio spp. pathogenic to fishes are investigated. Vibrio anguillarum, V. ordalii, V. alginolyticus, V. parahaemolyticus, an unidentified Vibrio sp. (AN1K), Pasteurella piscicida, and P. multocida were cultured on API-20E multitube test strips (Analytab Products) and in Baumann's marine media with similar results. The API-20E Profile Index was not useful for classification of fish bacteria studied and, using the index. Vibrio sp. AN1K was misidentified as P. multocida. Bacteria studied were also grown on Marine Agar (Difco) and on blood agar at 25 and 37 °C. On blood agar at 37 °C some vibrios resembled pasteurellas as a result of pleomorphism and lack of motility. Simple diagnostic procedures for identifying Pasteurella spp. and Vibrio spp. associated with fishes using the API-20E with modifications are presented.Key words: Pasteurella, Vibrio, characteristics, Analytical Profile Index, fish pathology
EFFECT OF DIELECTRIC SCREENING ON THE DIAMAGNETIC SUSCEPTIBILITY OF A DONOR IN LOW DIMENSIONAL SEMICONDUCTING SYSTEMS
Authors: NITHIANANTHI P. , VICKRAMAN P. , JAYAKUMAR K.
Published: April 2009

The effect of spatial dielectric screening on the diamagnetic susceptibility (χ dia ) of a donor in Low Dimensional Semiconducting Systems like Quantum Well, Quantum Well Wire and Quantum Dot in the infinite barrier model has been computed and investigated within the effective mass theory using variational method. We observe that the effect of spatial dielectric screening on χ dia decreases with decrease of dimensionality of the system.
ENTANGLEMENT OF TWO-QUBIT NONORTHOGONAL STATES
Authors: BERRADA K. , CHAFIK A. , ELEUCH H. , HASSOUNI Y.
Published: April 2009

We studied the entangled two-qubit nonorthogonal pure states through spin coherent states. Using the concurrence as a measure of entanglement we express it as a function of the amplitudes of those states and find conditions for maximal and minimal entanglement.
EXOTIC LAPLACIANS AND ASSOCIATED STOCHASTIC PROCESSES
Authors: ACCARDI LUIGI , JI UN CIG , SAITÔ KIMIAKI
Published: April 2009

In this paper, we give a decomposition of the space of tempered distributions by the Cesàro norm, and for any [Formula: see text] we construct directly from the exotic trace an infinite dimensional separable Hilbert space Hc,2a-1 on which the exotic trace plays the role as the usual trace. This implies that the Exotic Laplacian coincides with the Volterra–Gross Laplacian in the Boson Fock space Γ(Hc,2a-1) over the Hilbert space Hc,2a-1. Finally we construct the Brownian motion naturally associated to the Exotic Laplacian of order 2a-1 and we find an explicit expression for the associated heat semigroup.
THE STABILITY OF QUANTUM MARKOV FILTERS
Authors: HANDEL RAMON VAN
Published: April 2009

When are quantum filters asymptotically independent of the initial state? We show that this is the case for absolutely continuous initial states when the quantum stochastic model satisfies an observability condition. When the initial system is finite dimensional, this condition can be verified explicitly in terms of a rank condition on the coefficients of the associated quantum stochastic differential equation.
HIDA DISTRIBUTION CONSTRUCTION OF NON-GAUSSIAN REFLECTION POSITIVE GENERALIZED RANDOM FIELDS
Authors: ALBEVERIO SERGIO , YOSHIDA MINORU W.
Published: April 2009

Multiple stochastic integrals with respect to the Gaussian white noise indexed by Rdare used for the construction of reflection positive non-Gaussian [Formula: see text] valued random variables (random fields). This construction is then extended to a class of Hida distribution to consider several interesting examples. In particular, some new fields (without full Euclidean invariance but satisfying all other axioms, including space rotation invariance) are constructed through this probabilistic (and purely Euclidean) procedure.
GENERATING FUNCTIONS OF CAUCHY–STIELTJES TYPE FOR ORTHOGONAL POLYNOMIALS
Authors: BOŻEJKO MAREK , DEMNI NIZAR
Published: April 2009

We give a free probabilistic interpretation of the multiplicative renormalization method. As a byproduct, we give a short proof of the Asai–Kubo–Kuo problem on the characterization of the family of measures for which this method applies with h(x) = (1 - x)-1 which turns out to be the free Meixner family. We also give a representation of the Voiculescu transform of all free Meixner laws (even in the non-freely infinitely divisible case).
Aminoacyl-tRNA Synthesis and Translational Quality Control
Authors: Ling Jiqiang , Reynolds Noah , Ibba Michael
Published: April 2009

Translating the 4-letter code of RNA into the 22-letter alphabet of proteins is a central feature of cellular life. The fidelity with which mRNA is translated during protein synthesis is determined by two factors: the availability of aminoacyl-tRNAs composed of cognate amino acid:tRNA pairs and the accurate selection of aminoacyl-tRNAs on the ribosome. The role of aminoacyl-tRNA synthetases in translation is to define the genetic code by accurately pairing cognate tRNAs with their corresponding amino acids. Synthetases achieve the amino acid substrate specificity necessary to keep errors in translation to an acceptable level in two ways: preferential binding of the cognate amino acid and selective editing of near-cognate amino acids. Editing significantly decreases the frequency of errors and is important for translational quality control, and many details of the various editing mechanisms and their effect on different cellular systems are now starting to emerge.
Pulmonary artery banding alters the expression of Ca2+transport proteins in the right atrium in rabbits
Authors: Gupta Subash C. , Varian Kenneth D. , Bal Naresh C. , Abraham Jessica L. , Periasamy Muthu , Janssen Paul M. L.
Published: April 2009

Following pulmonary artery banding (PAB), the contractile function of right ventricle diminishes over time. Subsequently, the right atrium (RA) has to contract against a higher afterload, but it is unknown to what extent ventricular dysfunction has an effect on the atrial contractility. We hypothesized that right ventricular pressure overload may have an affect on atrial contractility and Ca2+transport protein expression. Therefore, we induced pressure overload of the right ventricle by PAB for 10 wk in rabbits and examined the changes in the expression of Ca2+transport proteins in the atrium. We demonstrate that PAB significantly decreased the expression of sarco(endo)plasmic reticulum Ca2+-ATPase (Serca) 2a while expression of Na+/Ca2+exchanger-1 was significantly upregulated in the RA but not in the left atria of rabbit hearts, indicating that pressure is the major trigger. A decrease in Serca2a expression was concomitant with a significant decrease in sarcolipin (SLN), possibly indicating a compensatory role of SLN. The decreased expression of SLN was unable to completely restore sarcoplasmic reticulum Ca2+uptake function of Serca2a. Functional contractile assessments in isolated trabeculae showed no difference between PAB- and sham-operated rabbits at 1 Hz but displayed an enhanced force development at higher frequencies and in the presence of isoproterenol, while twitch timing was unaffected. Our results indicate that right ventricular mechanical overload due to PAB affects the expression of the Ca2+-handling proteins in the RA in rabbits.
Effect of proteasome inhibitors on endotoxin-induced diaphragm dysfunction
Authors: Supinski G. S. , Vanags J. , Callahan L. A.
Published: April 2009

Infections produce severe respiratory muscle dysfunction. It is known that the proteasome proteolytic system is activated in skeletal muscle in sepsis, and it has been postulated that this degradative pathway is responsible for inducing skeletal muscle weakness and wasting. The objective of this study was to determine if administration of proteasomal inhibitors (MG132, epoxomicin, bortezomib) can prevent sepsis-induced diaphragm weakness. Rats were given either 1) saline (0.5 ml ip), 2) endotoxin (12 mg/kg ip), 3) endotoxin plus MG132 (2.5 mg/kg), 4) endotoxin plus epoxomicin (1 μmol/kg), or 5) endotoxin plus bortezomib (0.05 mg/kg). Animals were killed either 48 or 96 h after injections, and assessments were made of diaphragm proteolysis, force-frequency relationships, mass, protein content, and caspase activation. Endotoxin increased proteolysis ( P <0.001). MG132, epoxomicin, and bortezomib each prevented the endotoxin-induced increase in proteolysis ( P <0.01). Endotoxin induced severe reductions in diaphragm force generation by 48 h ( P <0.01); none of the proteasomal inhibitors prevented loss of force. Endotoxin induced significant reductions in diaphragm mass and protein content by 96 h ( P <0.01); neither MG132 nor epoxomicin prevented loss of mass or protein, but bortezomib attenuated the reduction in protein content ( P <0.05). Endotoxin increased diaphragm caspase-3 activity ( P <0.01); caspase-3 activity remained high when either MG132, epoxomicin, or bortezomib were given. These data suggest proteasomal inhibitors are not an adequate treatment to prevent endotoxin-induced diaphragmatic dysfunction.
Fifty Years of Research in Balkan Endemic Nephropathy: Where Are We Now?
Authors: Stefanović Vladisav , Polenaković Momir
Published: April 2009

Despite broad investigations into the possible role of genetic factors, environmental agents and immune mechanisms, the etiology of Balkan endemic nephropathy (BEN) is only partially understood. An increased incidence of upper urothelial cancer in patients with BEN and in populations from endemic settlements has been demonstrated. Genetic studies have landed support for genetic predisposition to BEN. The similarity of the morphological and clinical pattern of BEN and Chinese herbs nephropathy has raised the possibility of a common etiologic agent, aristolochic acid (AA), described in 1969 by Ivić and confirmed by a recent study of AA-DNA adducts. Ochratoxin A (OTA) is studied extensively as the etiologic agent of BEN. Weathering of low-rank coals nearby the endemic villages produces water-soluble polycyclic aromatic hydrocarbons and aromatic amines, similar to metabolic products of acetaminophen, which has a causal relationship with analgesic nephropathy. AA is confirmed as the etiologic agent of BEN; however, it may not be the sole risk factor. More research is needed on the patterns of BEN over time and between different endemic places. Therefore, it is important to test etiological hypotheses in different endemic foci, preferably as a multicentric research. An international approach to solving the etiology of BEN is needed in the coming years. The geographic correlation and presence of AA-DNA adducts in both BEN and associated urothelial cancer support the hypothesis that these diseases share a common etiology.
HLA-DR, -DQB Typing of Steroid-Sensitive Idiopathic Nephrotic Syndrome Children in Taiwan
Authors: Huang Yuan-Yuan , Lin Fang-Ju , Fu Lin-Shien , Lan Joung-Liang
Published: April 2009

Background: The association between human leukocyte antigens (HLA) and idiopathic nephrotic syndrome (INS) in children has been discussed in various studies. Methods: In this study, 59 Chinese children with steroid-sensitive nephritic syndrome (SSNS) in Taiwan were enrolled, and 33 patients underwent renal biopsy. Results: The frequency of HLA-DR11 was found to be significantly higher and HLA-DR14 was lower in SSNS patients as compared with the healthy control group. In frequent relapsers, HLA-DR4 was more frequent, while HLA-DQB1*0602 was less frequent, as compared with infrequent relapsers. However, there was no significant difference between steroid-dependent and non-steroid-dependent patients. In patients who showed a response to levamisole, the HLA-DR9 and -DQB1*0303 alleles were more frequent, while HLA-DR13 was less frequent. In a comparison of HLA in different INS pathologies, HLA-DQB1*0401 was significantly frequent in IgM nephropathy. Even though we compared each group with the control group separately, the HLA distributions of both groups still differed from each other. Our data suggest that the immunogenic characteristics of children with SSNS in Taiwan are different from those of other populations. The common motif between different HLA alleles and the three-dimensional crystal structures may offer an explanation for the varying results from different populations. Conclusion: According to HLA typing, the results support the hypothesis that IgM nephropathy is a different entity from minimal change nephrotic syndrome.
Alcohol Consumption and Kidney Function in IgA Glomerulonephritis
Authors: Kaartinen Kati , Niemelä Onni , Syrjänen Jaana , Pörsti Ilkka , Harmoinen Aimo , Pasternack Amos , Huhtala Heini , Mustonen Jukka
Published: April 2009

Background: IgA glomerulonephritis (IgAGN) is a kidney disease with variable prognosis. Several known risk factors exist for a more progressive course. Some population studies indicate that moderate alcohol consumption might protect kidney function, but the relationship between alcohol intake and IgAGN has not previously been examined. Methods: We examined 158 (95 men) IgAGN patients (37 abstainers, 80 light drinkers, 25 moderate drinkers and 16 heavy drinkers) in a cross-sectional study. The definition of alcohol consumption was based on interviews on the amounts of alcohol intake combined with measurements of serum carbohydrate-deficient transferrin, a specific biomarker of alcohol abuse. Longitudinal data on renal function were available from 117 patients (76 men) in whom an analysis with respect to progression was also performed. Results: Moderate drinkers showed the best kidney function. When adjusted by hypertension and 24-hour protein excretion, moderate alcohol consumption in a cross-sectional multivariate analysis, and both light and moderate alcohol consumption in a longitudinal multivariate analysis were significant factors of better kidney function. When the study population was divided by gender, the best kidney function was among light drinkers in women and among moderate drinkers in men. Conclusions: Moderate alcohol consumption might have a favorable impact on the progression of IgAGN. Light alcohol consumption in women and moderate consumption in men are associated with improved indices of the glomerular filtration estimates in patients with IgAGN.
Microarray and Bioinformatics Analysis of Gene Expression in Experimental Membranous Nephropathy
Authors: Hauser Peter V. , Perco Paul , Mühlberger Irmgard , Pippin Jeffrey , Blonski Mary , Mayer Bernd , Alpers Charles E. , Oberbauer Rainer , Shankland Stuart J.
Published: April 2009

Background: Passive Heymann nephritis (PHN), the best characterized animal model of experimental membranous nephropathy, is characterized by subepithelial immune deposits, podocyte foot processes effacement and massive proteinuria beginning 4 days following disease induction. Although single genes involved in PHN have been studied, no whole genome-wide expression analysis of kidney tissue has been performed. Methods: Microarray analysis was performed to identify gene expression changes in PHN rat kidneys during the onset of proteinuria. Results: Our results showed that 234 transcripts were differentially expressed in diseased animals compared to controls. Genes exclusively upregulated in diseased animals were mainly required for cell structure and motility, immunity and defense, cell cycle, and developmental processes. The single most increased gene was transgelin (Tagln) showing a 70-fold upregulation in animals with PHN. Protein-protein interaction analysis revealed the following four processes of major relevance in disease manifestation: (i) DNA damage and repair; (ii) changes in the extracellular matrix; (iii) deregulation of cytokines and growth factors, as well as (iv) rearrangements of the cytoskeleton. Conclusion: We show for the first time the complex interplay between multiple different genes in experimental membranous nephropathy, supporting a role for genomic approaches to better understanding and defining specific disease processes.
OCRL1 Mutations in Dent 2 Patients Suggest a Mechanism for Phenotypic Variability
Authors: Shrimpton Antony E. , Hoopes, Jr. Richard R. , Knohl Stephen J. , Hueber Paul , Reed Anita A.C. , Christie Paul T. , Igarashi Takashi , Lee Philip , Lehman Anna , White Colin , Milford David V. , Sanchez Manuel Rivero , Unwin Robert , Wrong Oliver M. , Thakker Rajesh V. , Scheinman Steven J.
Published: April 2009

Background/Aims: Dent disease is an X-linked renal proximal tubulopathy associated with mutations in CLCN5 (Dent 1) or OCRL1 (Dent 2). OCRL1 mutations also cause the oculocerebrorenal syndrome of Lowe. Methods: Dent patients with normal sequence for CLCN5 were sequenced for mutations in OCRL1. By analyzing these and all other OCRL1 mutations reported, a model relating OCRL1 mutations to the resulting disease (Dent 2 or Lowe’s) was developed. Results: Six boys with Dent disease had novel OCRL1 mutations: two missense (R301H, G304E) and four mutations predicted to produce premature termination codons (L56DfsX1, S149X, P161PfsX3, and M170IfsX1). These include one of the original patients reported by Dent and Friedman. Slit lamp examinations revealed early cataracts in only one boy with normal vision. None of these Dent 2 patients had metabolic acidosis; 3 had mild mental retardation. Analysis of all known OCRL1 mutations show that Dent 2 mutations fall into two classes that do not overlap with Lowe mutations. Bioinformatics analyses identified expressed OCRL1 splice variants that help explain the variability of those clinical features that distinguish Dent disease from Lowe syndrome. Conclusions:OCRL1 mutations can cause the renal phenotype of Dent disease, without acidosis or the dramatic eye abnormalities typical of Lowe syndrome. We propose a model to explain the phenotypic variability between Dent 2 and Lowe’s based on distinctly different classes of mutations in OCRL1 producing splice variants.
Microaneurysm Turnover Is a Biomarker for Diabetic Retinopathy Progression to Clinically Significant Macular Edema: Findings for Type 2 Diabetics with Nonproliferative Retinopathy
Authors: Nunes Sandrina , Pires Isabel , Rosa Andreia , Duarte Lilianne , Bernardes Rui , Cunha-Vaz José
Published: April 2009

Purpose: To examine the relationship between microaneurysm turnover (formation rate), using a new semi-automatic method (MA-Tracker) based on color fundus photographs, and diabetic retinopathy (DR) progression to clinically significant macular edema (CSME). Methods: In total, 113 patients/eyes with nonproliferative DR (NPDR) were followed up every 6 months for 2 years as controls of the DR clinical trials, and by conventional general and ophthalmological care for the next 8 years (over a total of 10 years’ follow-up). Microaneurysm turnover for the 2 first years was computed using the MA-Tracker. Results: The 17 patients that developed CSME over the 10 years of follow-up presented a microaneurysm formation rate of 9.2 ± 18.2 microaneurysms/year (mean ± SD) during the first 2 years, which was statistically higher than the eyes that did not develop CSME (0.5 ± 1.2 microaneurysms/year, p < 0.001). These 17 patients also presented higher HbA1C levels at baseline (8.5 ± 1.2%) compared to the patients who did not develop CSME (7.3 ± 1.2%, p = 0.001). Conclusions: A high microaneurysm formation rate on color fundus photographs appears to be a good biomarker for DR progression to CSME in type 2 diabetic patients with NPDR.
Determination of Fast-Acting Plasmin Inhibitor (α2-Antiplasmin) in Plasma from Patients with Tendency to Thrombosis and Increased Fibrinolysis
Authors: Teger-Nilsson Ann-Catrine , Gyzander Erika , Myrwold Helge , Noppa Henry , Olsson Rolf , Wallmo Leif
Published: April 2009

The physiologically important α2-antiplasmin has been measured by aid of a chromogenic tripeptide substrate. Low values in patients’ plasmas are found in situations with increased fibrinolysis such as streptokinase therapy and liver cirrhosis, whereas high values are found postoperatively, postpartum and after an acute thrombosis.
Alterations of Plasmin Activity, Plasminogen Levels and Activity of Antiplasmins during Endotoxin Shock in Dogs
Authors: Aasen Ansgar O. , Gallimore Michael J. , Ohlsson Kjell , Amundsen Egil
Published: April 2009

Spontaneous plasmin activity and ‘fast-reacting’ and ‘time-dependent’ antiplasmin activities were determined during various stages of canine endotoxin shock by means of assays utilizing a chromogenic tripeptide derivative (S -2251, Kabi AB, Peptide Research Division, Mölndal). During shock, gradually decreasing values of both antiplasmins were found, revealing most pronounced falls of ‘fast-reacting’ antiplasmin. These changes of plasma antiplasmin activities were accompanied by decreasing values of plasminogen and evidence of plasmin activity. Immunochemical determination of plasma levels of α2-macro-globulin (α2-M) and α1-antitrypsin (α1-AT) and gel filtration studies, demonstrated marked falls in levels of α2-M and α2-plasmin inhibitor and small reductions of α1-AT in this state.
Chromogenic Substrates for Horseshoe Crab Clotting Enzyme
Authors: Iwanaga Sadaaki , Morita Takashi , Harada Toshie , Nakamura Shin , Niwa Makoto , Takada Katsumi , Kimura Terutoshi , Sakakibara Shunpei
Published: April 2009

An endotoxin-activated hemocyte lysate from the horseshoe crab (Tachy-pleus and Limulus) was found to hydrolyze Bz-Ile-Glu-(γ-OR)-Gly-Arg-p-nitroanilide (PNA), Bz-Val-Gly-Arg-PNA, Boc-Val-Leu-Gly-Arg-PNA, and Boc-Leu-Gly-Arg-PNA, all of which have the COOH-terminal Gly-Arg sequence. This amidase activity was due to a clotting enzyme contained in the lysate. Furthermore, the amidase activity increased by increasing the concentration of bacterial endotoxin (E. coli, 0111-B4) added to the lysate. Therefore, the measurement of the endotoxin-induced amidase activity made it possible to determine the concentration of the endotoxin.
Acetylsalicylic Acid and the Cardiovascular Effects of ADP in the Rat
Authors: Dejana Elisabetta , Bonaccorsi Aurora , de Gaetano Giovanni
Published: April 2009

Acetylsalicylic acid (ASA) did not prevent the arrhythmias induced in rats by a bolus intravenous injection of ADP, an effect independent of platelets. ASA was also unable to protect the rats from the platelet-mediated cardiovascular effects and myocardial ischaemia induced by a prolonged ADP infusion. It is suggested that the release of vasoactive substances inhibited by ASA does not play a major role in the cardiovascular effects of ADP in rats.
Platelet Adhesion and Platelet Thrombus Formation on Subendothelium of Human Arteries and Veins Exposed to Flowing Blood in vitro. A Comparison with Rabbit Aorta
Authors: Tschopp T.B. , Baumgartner H.R. , Silberbauer K. , Sinzinger H.
Published: April 2009

Subendothelium of blood vessel segments from elderly patients was exposed in a perfusion chamber to citrated blood under arterial blood flow conditions. The resulting platelet adhesion and thrombus formation was assessed morphometrically. The results show that the time course and the extent of platelet adhesion and aggregation were similar to the results obtained previously with subendothelium from rabbit arteries. The extent of surface-induced platelet aggregation was furthermore governed by both the properties of the exposed surface as well as those of the blood perfusate. No significant differences with regard to platelet reactivity were found between veins and arteries and the extent of surface-induced platelet aggregation was rather low.
Low-Dose Heparin in Gynecologic Surgery: Effect on Blood Coagulation Tests
Authors: Levesque G. , Samama M. , Kher A. , Barbier P. , Horellou M.H. , Conard J.
Published: April 2009

The laboratory control of low-dose heparin therapy is generally regarded as unnecessary. A laboratory study of the effects of low-dose heparin was performed using different methods: an amidolytic method and a method involving the inhibition of factor Xa in a coagulation test. Variations in partial thromboplastin time, recalcification clotting time, thrombin time and the plasma antithrombin HI levels were also studied. These tests were repeated (days 0, 1, 3, 8) in 27 women between the ages of 27 and 62 years who were undergoiing gynecological surgery. They received 5,000 IU of heparin either twice or thrice daily. There was no correlation between heparin levels in the blood and global clotting tests simultaneously performed. The plasma heparin levels varied between 0 and 0.15 IU/ml with both methods. A detectable heparin concentration on days 1, 3 and 8 was present in only half of the cases receiving the twice daily regimen. The plasma antithrombin III activity and concentration were not modified during treatment.
Generation of Fibrinolytic Activity in Bovine Plasma by the Combined Effects of Chloroform and Dextran Sulphate
Authors: Jenks Rodney L. , Kluft Cornells , Astrup Tage
Published: April 2009

Bovine plasma yields fibrinolytically inactive euglobulin fractions, even when prepared in the presence of dextran sulphate. Addition of flufenamate to these solutions only occasionally elicits a slight activity. However, highly fibrinolytic solutions are produced when euglobulins precipitated in the presence of dextran sulphate are exposed to chloroform. Evidence indicates that a plasminogen activator is formed, which subsequently converts plasminogen present in the fractions to plasmin. Bovine euglobulin fractions contain an inhibitor which seems to be specifically directed towards urokinase and not to plasmin or to tissue plasminogen activator. Its inhibiting capacity is decreased after treatment with chloroform.
Storage Pool Disease of Platelets in an Infant with Thrombocytopenic Absent Radii (TAR) Syndrome Simulating Fanconi’s Anaemia
Authors: Zahavi J. , Gale R. , Kakkar V.V.
Published: April 2009

This study reports the first example of ‘storage pool disease’ thrombocyto-pathia B (aspirin-like) in the family of a 4-month-old infant with thrombocytopenic absent radii (TAR) syndrome. In the infant and his father, platelet ADP and 5HT stores were normal, bleeding time was prolonged, released platelet anti-heparin activity, platelet aggregation (PA) to collagen and secondary aggregation to ADP were all significantly decreased and PA to l-epinephrine totally absent. Platelet function studies of the mother, a first cousin to her husband, were normal. This report provides further evidence to the hereditary nature of TAR syndrome. The impaired platelet function is a valuable aid in the diagnosis of TAR syndrome and Fanconi’s anaemia.
The Effects of Two Different Dosage Regimens of Sulphinpyrazone on Platelet Function ex vivo and Blood Chemistry in Man
Authors: Maguire Eric D. , Pay Graham F. , Turney John , Wallis Robert B. , Weston Michael J. , White Alan M. , Williams Laurie C. , Woods Feidhlim
Published: April 2009

When sulphinpyrazone (either 200 mg q.d.s. for 7 days or 400 mg b.d.s. for 5 days) was administered to human volunteers, inhibition of platelet function was observed ex vivo. The inhibitory effect was measured by the increase in the concentration of sodium arachidonate required to cause platelet aggregation and a decrease in the biosynthesis by the platelets of malondialdehyde from added sodium arachidonate. ADP-induced primary platelet aggregation was statistically significantly inhibited only on 1 day of the two studies. The inhibitory effect did not correlate with the plasma concentrations of unchanged sulphinpyrazone nor with its sulphone metabolite but correlated with the plasma concentration of the thioether metabolite (r = 0.577, p < 0.001). Platelet count, plasma fibrinogen, β-thromboglobulin, urea and creatinine concentrations were not changed by the drug but there was a clinically insignificant increase in bleeding time in all but one subject.
Neonatal Platelet Function: A Membrane-Related Phenomenon?
Authors: Corby Donald G. , O’Barr Thomas P.
Published: April 2009

Synthesis of prostaglandin endoperoxides was evaluated in paired maternal and cord blood samples. Platelets from mothers and neonates aggregated normally in response to arachidonic acid (AA). Cyclooxygenase activity was evaluated by. monitoring the incorporation of radioactivity into prostaglandin endoperoxide metabolites after incubation with 1-14C-AA. Thin layer radiochromatograms of methylated incubation products revealed three main peaks corresponding to 12-L-hydroxy-5,8,10,14-eicosatetraenoic acid, 12-L-hydroxy-5,8,10-heptadecatrienoicacid(HHT), and 8-(l-hydroxy-3-oxopropyl)-9,12-L-dihydroxy-5,10-heptadecadienoic acid (TXB2). Maternal and neonatal platelets incorporated similar amounts of radioactivity into HHT and TXB2. Radioimmunoassay for TXB2 in thrombin-clotted PRP revealed no significant differences between maternal and neonatal platelets. Since these metabolites are derived from cyclic endoperoxides formed by the action of cyclooxygenase on AA, we conclude that prostaglandin endoperoxide synthesis is fully developed in neonatal platelets. Mutual correction of collagen-induced platelet aggregation and ADP release was observed when equal volumes of neonatal and aspirin-treated adult platelet-rich plasma were mixed. Therefore, since neonatal platelets contain normal amounts of storage pool nucleotides, we also conclude that the defective secondary aggregation and release seen in neonatal platelets is caused by a failure in the release of AA from membrane phospholipids upon stimulation with collagen or epinephrine.
The Effect of Isolated Leukaemic Blasts on Platelet Aggregation
Authors: Zawilska K. , Komarnicki M. , Trepińska E. , Sokołowski K. , Wysocki K.
Published: April 2009

The effect of blastic cells isolated by Böyum’s method from the blood of 20 nontreated patients with acute myelogenous leukaemia on normal platelet aggregation has been studied. The isolated blasts in concentration of 2,000/µl and higher, inhibit normal platelet aggregation induced by ADP or collagen, but have no influence on aggregation initiated by epinephrine. This effect is unaffected by the presence of metabolic poisons or by the disruption of the blastic cell membrane. Our results seem to exclude interference of blastic cells with platelet prostaglandin biosynthesis. In patients with acute leukaemia and an increased leukocyte count the preparation of platelet suspension free of blastic cells is not possible, even by the albumin gradient method or by gel filtration. The leukaemic blast content in platelet-rich suspensions may account for the variations in the aggregation behaviour which are found in these patients. The influence of blastic cells may be an important factor in the bleeding tendency in myelogenous leukaemia.
Non-Enzymatic Glucosylation of Fibrinogen
Authors: McVerry B.A. , Thorpe S. , Joe F. , Gaffney P. , Huehns E.R.
Published: April 2009

Glucose, when incubated with fibrinogen, binds covalently to that protein. The reaction is non-enzymatic in type and is directly dependant on the time of incubation, temperature and pH. Glucosylation of fibrinogen is not altered by preincubation with aspirin. No preferential glucosylation of fibrinogen, fibrinogen chains or plasmin digestion products XYDE could be demonstrated, suggesting that glucose binding occurs at several different sites. No abnormality of thrombin clotting or stability of glucosylated fibrinogen could be detected. These findings are discussed in relation to the previously described abnormalities of fibrinogen metabolism in diabetes mellitus.
Automated Estimation of Factor Xa Using the Chromogenic Substrate S-2222
Authors: Madaras F. , Chew M.Y. , Parkin J.D.
Published: April 2009

A rapid automated method for the estimation of factor Xa was developed using the ‘Centrifichem’ rotary fast analyser and the substrate S-2222. The problem of interference from fibrin was overcome by performing the activation of factor X during centrifugation, so that defibrination and activation were achieved in a single step. A range of factor Xa concentrations was determined on 50 normal plasmas. This assay was correlated with a clotting assay of factor Xa using serial dilutions of normal plasma and plasma from 30 patients receiving warfarin therapy.
Urokinase Treatment for Severe Neurological Complications in a Patient with Thrombotic Thrombocytopenic Purpura
Authors: Vesconi Sergio , Langer Martin , Rossi Edoardo , Donati Maria Benedetta
Published: April 2009

In a patient with thrombotic thrombocytopenic purpura (TTP) severe neurological complications leading to coma were repeatedly reversed by treatment with urokinase. Although the therapeutic modalities for TTP still appear to be a matter of debate, thrombolytic treatment could be considered in TTP patients with severe organ involvement before the corresponding function is completely compromised.
Plasmapheresis: Its Value in the Management of Patients with Antibodies to Factor VIII
Authors: Francesconi M. , Korninger C. , Thaler E. , Niessner H. , Höcker P. , Lechner K.
Published: April 2009

12 plasmaphereses were carried out in 5 patients with antibodies to F VIII (3 haemophilic antibodies; 2 spontaneous antibodies). Plasmapheresis led in all instances to a marked reduction of the antibody level and there was a good correlation between the amount of plasma exchanged and the decrease of the antibody level. About 40 ml of plasma/kg body weight have to be removed to reduce the antibody level to half. In patients with low titre antibody who need treatment for serious bleeding, plasmapheresis is a more rapid and less expensive procedure than neutralisation of the inhibitor by high doses of F VIII. In one haemophiliac repeated plasmaphereses and subsequent high dose F VIII treatment eliminated the antibody within a short time. Plasmapheresis should always be considered when patients with antibodies to F VIII have to be treated because of severe bleeding.
Preparation of a Stable Phospholipid Reagent for Coagulation Assays
Authors: Barrowcliffe T.W. , Stocks J. , Gray E.
Published: April 2009

Modifications are described to the methods of extraction of phospholipids from brain tissue which were successful in diminishing the oxidative changes taking place during extraction. The reagents produced, particularly when prepared by a modified Folch procedure, were stable and had reproducible coagulant activities.
75SE-Methionine Platelet Survival Studies: a Proposal for a Mathematical Correction of the Curve
Authors: Fabris Fabrizio , Casonato Alessandra , Randi Maria Luigia , Varotto Lucia , Scandellari Cesare , Girolami Antonio
Published: April 2009

We studied platelet survival in 14 cardiac patients before heart valve replacement using 75Se-methionine ‘cohort label’. The temporal variation of plasma and platelet activity was plotted by a continuous curve by means of a computerized interaction of the single points. Then we computed the plasmatic radioactivity fraction used daily for thrombo-poiesis and made a subtraction of this aliquot from the experimental activity in the catabolic phase of the slope. Platelet life span obtained after this ‘correction’ is comparable with the values of random label using 51Cr.
Platelet Thromboxane Synthesis and Release Reactions in Myeloproliferative Disorders
Authors: Smith I.L. , Martin T.J.
Published: April 2009

A group of patients with myeloproliferative disorders was studied with respect to platelet aggregation responses, release of β-thromboglobulin and incorporated 5-hydroxy-tryptamine, and synthesis of thromboxane B2. In all patients the resting plasma β-thrombo-globulin was elevated. Aggregation responses were frequently impaired to adrenaline, arachi-donic acid, A23187 and the prostaglandin endoperoxide analogue, U44069. Both 5-hydroxy-tryptamine and β-thromboglobulin release were greater with patients’ platelets than with those of controls in response to adrenaline, ADP and U44069. The patients’ platelets produced more thromboxane B2 than did controls, irrespective of the agonist used, yet those aggregating agents which are thought to act by generating thromboxane A2 were relatively ineffective in causing aggregation. This might reflect resistance to thromboxane A2 action in these patients, which is met by increased thromboxane formation.
Binding of Adenosine Diphosphate to Turkey Thrombocytes
Authors: Wachowicz Barbara
Published: April 2009

Adenosine diphosphate (ADP) caused rapid and reversible aggregation of turkey thrombocytes, as determined by optical and microscopical examination. To investigate the binding of ADP to these cells, turkey thrombocyte-rich plasma was incubated with ADP-8–14C or ADP-3–3H and with human serum albumin labeled with 125I. The thrombocytes were rapidly separated by centrifugation through silicone oil. From radioactivity determination of plasma and thrombocyte pellets the uptake of ADP radioactivity by thrombocytes was calculated. Scatchard analysis of concentration-dependent binding yielded a hyperbolic plot which indicates that turkey thrombocytes similarly to human platelets have more than one type of binding site for ADP.
Influence of Brinase on Fibrinogen: Fibrin Transition in in vitro and in vivo Studies
Authors: Saldeen T. , Frisch E.P.
Published: April 2009

The influence of brinase on fibrinogen levels, ethanol gelation test (EGT), fibrin content of lungs and kidneys (125I-fibrinogen) and brinase inhibitor capacity was investigated in the rat. The animals were either treated with i.v. infusions of brinase (4 mg/kg), tranexamic acid (AMCA) + brinase or heparin + AMCA + brinase. A control group was given i.v. saline, a reference group AMCA + thrombin. Brinase caused a decrease in fibrinogen levels and an increase in the incidence of positive EGT, deposition of fibrin was not observed. Infusion of brinase into rats with inhibited fibrinolytic system (AMCA), caused a more pronounced decrease in fibrinogen levels, a further increase in the incidence of positive EGT and also fibrin deposition in the kidneys. In rats treated with AMCA + thrombin a similar decrease in fibrinogen levels was recorded, the EGT was positive in all animals, and extensive fibrin deposits were observed in the kidneys and lungs of the animals. Heparinization before infusion of AMCA + brinase antagonized the lowering in fibrinogen levels and the increase in incidence of positive EGT and, moreover, fibrin deposits were no longer observed.
Fibrinogen-Bound Sialic Acid Levels in the Dysfibrinogenaemia of Liver Disease
Authors: Francis J.L. , Armstrong D.J.
Published: April 2009

Fibrinogen-bound sialic acid levels were determined in 75 normal controls and 80 patients with liver disease. Patients with abnormal fibrin monomer polymerisation (FMP) had sialic acid levels significantly higher than normal controls or patients with normal FMP. Enzymatic removal of sialic acid from the abnormal fibrinogens corrected the abnormal FMP and thrombin-clotting times to the range of desialated controls. The accelerating effects of calcium ions, protamine sulphate and Polybrene were largely abolished by desialation, suggesting that these cations accelerate FMP by neutralising the negatively charged sialic acid residues.
Sialic Acid and Enzymatic Desialation of Cord Blood Fibrinogen
Authors: Francis J.L. , Armstrong D.J.
Published: April 2009

Fibrinogen-bound sialic acid was determined in a large series of normal adult, full-term and pre-term cord blood samples. Sialic acid was significantly higher in full-term cord fibrinogen than controls, and higher in premature than term samples. Enzymatic desialation of full-term fibrinogens corrected the abnormal thrombin times and fibrin polymerisation to normal or near-normal values. There was significant correlation between sialic acid content and thrombin time in full-term cord samples. It is concluded that fetal fibrinogen is characterised by an elevated sialic acid content, and that the degree of hypersialation is a function of gestational age.
Effect of EACA, PAMBA, AMCA and AMBOCA on Fibrinolysis Induced by Streptokinase, Urokinase and Tissue Activator
Authors: Westlund Lars E. , Lundén Ragnar , Wallén Per
Published: April 2009

A study is presented in which the inhibiting effects of EACA, PAMBA, AMCA and AMBOCA on fibrinolysis induced by three activators have been compared by a clot lysis method. The order of inhibitory potency was AMBOCA > AMCA > PAMBA > EACA. The activity ratios obtained were found to be influenced by the level of inhibition. At low levels of inhibition the differences between the inhibitory activities are usually more pronounced than at high levels. The degree of inhibition is dependent on the fibrinolytic activator used. The order of sensitivity to the inhibitors was, within the analytical conditions used, found to be: tissue activator > streptokinase > urokinase. The results are discussed in comparison to the different activity ratios reported by others.