Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailDifferential regulation of the REGγ–proteasome pathway by p53/TGF-β signalling and mutant p53 in cancer cells
Ali, Amjad ULg; wang, zhou; Fu, Junjiang et al

in Nature Communications (2013), 1(4), 1-16

Proteasome activity is frequently enhanced in cancer to accelerate metastasis and tumorigenesis. REGγ, a proteasome activator known to promote p53/p21/p16 degradation, is often overexpressed in cancer ... [more ▼]

Proteasome activity is frequently enhanced in cancer to accelerate metastasis and tumorigenesis. REGγ, a proteasome activator known to promote p53/p21/p16 degradation, is often overexpressed in cancer cells. Here we show that p53/TGF-β signalling inhibits the REGγ–20S proteasome pathway by repressing REGγ expression. Smad3 and p53 interact on the REGγ promoter via the p53RE/SBE region. Conversely, mutant p53 binds to the REGγ promoter and recruits p300. Importantly, mutant p53 prevents Smad3/N-CoR complex formation on the REGγ promoter, which enhances the activity of the REGγ–20S proteasome pathway and contributes to mutant p53 gain of function. Depletion of REGγ alters the cellular response to p53/TGF-β signalling in drug resistance, proliferation, cell cycle progression and proteasome activity. Moreover, p53 mutations show a positive correlation with REGγ expression in cancer samples. These findings suggest that targeting REGγ–20S proteasome for cancer therapy may be applicable to human tumours with abnormal p53/Smad protein status. Furthermore, this study demonstrates a link between p53/TGF-β signalling and the REGγ–20S proteasome pathway, and provides insight into the REGγ/p53 feedback loop. [less ▲]

Detailed reference viewed: 10 (1 ULg)
Full Text
Peer Reviewed
See detailDifferential regulation of wild-type and mutant alpha-synuclein binding to synaptic membranes by cytosolic factors.
Wislet-Gendebien, Sabine ULg; Visanji, Naomi P; Whitehead, Shawn N et al

in BMC Neuroscience (2008), 9

BACKGROUND: Alpha-Synuclein (alpha-syn), a 140 amino acid protein associated with presynaptic membranes in brain, is a major constituent of Lewy bodies in Parkinson's disease (PD). Three missense ... [more ▼]

BACKGROUND: Alpha-Synuclein (alpha-syn), a 140 amino acid protein associated with presynaptic membranes in brain, is a major constituent of Lewy bodies in Parkinson's disease (PD). Three missense mutations (A30P, A53T and E46K) in the alpha-syn gene are associated with rare autosomal dominant forms of familial PD. However, the regulation of alpha-syn's cellular localization in neurons and the effects of the PD-linked mutations are poorly understood. RESULTS: In the present study, we analysed the ability of cytosolic factors to regulate alpha-syn binding to synaptic membranes. We show that co-incubation with brain cytosol significantly increases the membrane binding of normal and PD-linked mutant alpha-syn. To characterize cytosolic factor(s) that modulate alpha-syn binding properties, we investigated the ability of proteins, lipids, ATP and calcium to modulate alpha-syn membrane interactions. We report that lipids and ATP are two of the principal cytosolic components that modulate Wt and A53T alpha-syn binding to the synaptic membrane. We further show that 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (C16:0 PAF) is one of the principal lipids found in complex with cytosolic proteins and is required to enhance alpha-syn interaction with synaptic membrane. In addition, the impaired membrane binding observed for A30P alpha-syn was significantly mitigated by the presence of protease-sensitive factors in brain cytosol. CONCLUSION: These findings suggest that endogenous brain cytosolic factors regulate Wt and mutant alpha-syn membrane binding, and could represent potential targets to influence alpha-syn solubility in brain. [less ▲]

Detailed reference viewed: 45 (8 ULg)
Full Text
See detailDifferential reinforcement of perching duration in the pigeon : a comparison with differential-reinforcement-of-low-rate key-pecking
Lejeune, Helga ULg; Richelle, Marc ULg

in Behaviour Analysis Letters (1982), 2

Pigeons were required to jump on a perch and sit on it for a specified duration before stepping off, in order to gain access to food. This duration was progressively increased by 1-sec steps. Median ... [more ▼]

Pigeons were required to jump on a perch and sit on it for a specified duration before stepping off, in order to gain access to food. This duration was progressively increased by 1-sec steps. Median response duration approximated the required repsonse duration up to values of 40 or even 50 sec and efficiency remained high. Response duration distribution had sharp peaks and comparable dispersions throughout the critical values range. These results contrast with the performance of the same birds in a conventional differential-reinforcement-of-low-rate schedule involving a key-peck response. This indicates that pigeons are able to regulate in time their own motor behaviour over much longer time intervals in the case of a perching response than in the case of key-pecking. [less ▲]

Detailed reference viewed: 21 (0 ULg)
Full Text
Peer Reviewed
See detailDifferential resistance/susceptibility patterns to pneumovirus infection among inbred mouse strains
Bui Tran Anh, Dao; Faisca, Rui-Pedro; Desmecht, Daniel ULg

in American Journal of Physiology - Lung Cellular and Molecular Physiology (2006), 291

Respiratory syncytial virus (RSV) is a prominent cause of airway morbidity in children under 1 yr of age. It is assumed that host factors influence the severity of the disease presentation and thus the ... [more ▼]

Respiratory syncytial virus (RSV) is a prominent cause of airway morbidity in children under 1 yr of age. It is assumed that host factors influence the severity of the disease presentation and thus the need for hospitalization. As a first step toward the identification of the underlying genes involved, this study was undertaken to establish whether inbred mouse strains differ in susceptibility to pneumonia virus of mice (PVM), the murine counterpart of RSV, which has been shown to accurately mimic the RSV disease of children. With this purpose in mind, double-chamber plethysmography and carbon monoxide uptake data were collected daily for 7 days after inoculation of PVM in six inbred strains of mice. In parallel, histological examinations and lung viral titration were carried out from day 5 to day 7 after inoculation. Pulmonary structure/function values reflected the success of viral replication in the lungs and revealed a pattern of continuous variation, with resistant, intermediate, and susceptible strains. The results suggest that SJL (resistant) and 129/Sv (susceptible) strains should be used in crossing experiments aimed at identifying genes controlling pneumovirus replication by the positional cloning approach. Similarly, crossing experiments using BALB/c or C57BL/6 (resistant) and DBA/2 or 129/Sv (susceptible) will allow the identification of the genes involved in the control of pulmonary inflammation during pneumovirus infection. [less ▲]

Detailed reference viewed: 75 (6 ULg)
Full Text
Peer Reviewed
See detailDifferential responsiveness between broiler and layer embryos upon different doses of L-carnitine administration. 1. Hatchability and blood parameters
Tona, K.; Nouboukpo, K. E.; Willemsen, H. et al

in Archiv Für Geglügelkunde = European Poultry Science = Revue de Science Avicole Européenne (2013), 77(4), 240-246

L-carnitine enhances the transport of long chain fatty acids through mitochondrial membrane. It can be produced by animals' organism from lysine and methionine. However, it was reported that chicken ... [more ▼]

L-carnitine enhances the transport of long chain fatty acids through mitochondrial membrane. It can be produced by animals' organism from lysine and methionine. However, it was reported that chicken embryos have a limited capacity to synthesize L-carnitine. For this study, hatching eggs from Ross and Isa Brown breeders of 35 wk old (600 eggs per line) were used. At d 18 of incubation, eggs from each genotype were divided into 4 groups i.e. control eggs, Saline (injection of saline solution), eggs injected with L-carnitine of 500 μmol (LC500) or 1000 μmol (LC1000). At hatch and 7 d post hatch, blood samples were collected for triglyceride, glucose, total protein, uric acids, triiodothyronine (T3), thyroxine (T4) and corticosterone concentrations determination. Results indicate that hatchability and percentage of chick of optimal quality were higher in Ross than Isa Brown. Overall, layer chicks had higher levels of T4, total protein and uric acid than broiler chicks. With regard to L-carnitine injection, eggs of LC1000 groups had the lowest hatchability and this negative effect was more pronounced in Isa Brown eggs. At hatch and 7 d post-hatch, control chicks had the lowest levels of triglyceride and T3 but the highest levels of T4. At 7 d-old, the highest and the lowest levels of corticosterone were obtained in chicks of LC1000 and LC500 groups, respectively, compared to control and saline groups. In conclusion, L-carnitine administration during embryonic life affected differentially hatchability and blood parameters during post-hatch juvenile growth and this in a dose dependent manner. © Verlag Eugen Ulmer, Stuttgart. [less ▲]

Detailed reference viewed: 58 (4 ULg)
Full Text
Peer Reviewed
See detailDifferential role of snail1 and snail2 zinc fingers in E-cadherin repression and epithelial to mesenchymal transition
Villarejo; Cortés-Cabrera, Alvaro; Molina Ortiz, Patricia ULg et al

in Journal of Biological Chemistry (2014), 289(2), 930-941

Snail1 (Snail) and Snail2 (Slug) are transcription factors that share a similar DNA binding structure of four and five C2H2 zinc finger motifs (ZF), respectively. Both factors bind specifically to a ... [more ▼]

Snail1 (Snail) and Snail2 (Slug) are transcription factors that share a similar DNA binding structure of four and five C2H2 zinc finger motifs (ZF), respectively. Both factors bind specifically to a subset of E-box motifs (E2-box: CAGGTG/CACCTG) in target promoters like the E-cadherin promoter and are key mediators of epithelial-to-mesenchymal transition (EMT). However, there are differences in the biological actions, in binding affinities to E-cadherin promoter, and in the target genes of Snail1 and Snail2, although the molecular bases are presently unknown. In particular, the role of each Snail1 and Snail2 ZF in the binding to E-boxes and in EMT induction has not been previously explored. We have approached this question by modeling Snail1 and Snail2 protein-DNA interactions and through mutational and functional assays of different ZFs. Results show that Snail1 efficient repression and binding to human and mouse E-cadherin promoter as well as EMT-inducing ability require intact ZF1 and ZF2, while for Snail2, either ZF3 or ZF4 is essential for those functions. Furthermore, the differential distribution of E2-boxes in mouse and human E-cadherin promoters also contributes to the differential Snail factor activity. These data indicate a non-equivalent role of Snail1 and Snail2 ZFs in gene repression, contributing to the elucidation of the molecular differences between these important EMT regulators. [less ▲]

Detailed reference viewed: 32 (3 ULg)
Full Text
Peer Reviewed
See detailDifferential roles of lipopeptides in plant host defenses and pathogen suppression.
Ongena, Marc ULg; Henry, G.; Jourdan, Emmanuel ULg et al

in Phytopathology (2010), 100

Detailed reference viewed: 15 (4 ULg)
Peer Reviewed
See detailDifferential roles of lipopeptides(LPs) in plant host defenses and pathogen suppression.
Ongena, Marc ULg; Henry, G.; Jourdan, E. et al

Conference (2010)

Detailed reference viewed: 9 (0 ULg)
See detailDifferential Seismic Modeling of Stars
Ozel, N.; Mosser, B.; Dupret, Marc-Antoine ULg et al

in Astronomical Society of the Pacific Conference Series (2013, December 01)

CoRoT (Convection Rotation and planetary Transits) observations provide the opportunity to study a large sample of stars ranging from the Main Sequence (MS) to the Red Giant Branch. With the large ... [more ▼]

CoRoT (Convection Rotation and planetary Transits) observations provide the opportunity to study a large sample of stars ranging from the Main Sequence (MS) to the Red Giant Branch. With the large increase in the number of stars showing solar-like oscillations, we intend to extract as much information as possible from a low signal-to-noise ratio (SNR) oscillation spectrum, benefiting from comparison with a reference star having similar seismic and fundamental parameters. We propose a differential method to determine stellar properties of solar-like oscillations which we call “differential seismology of stellar twins”. [less ▲]

Detailed reference viewed: 17 (0 ULg)
Full Text
Peer Reviewed
See detailDifferential sensitivity of two insect GABA-gated chloride channels to dieldrin, fipronil and picrotoxinin
Le Corronch, Hervé; Alix, Philippe ULg; Hue, B

in Journal of Insect Physiology (2002), 48

In the central nervous system of both vertebrates and invertebrates inhibitory neurotransmission is mainly achieved through activation of gamma-aminobutyric acid (GABA) receptors. Extensive studies have ... [more ▼]

In the central nervous system of both vertebrates and invertebrates inhibitory neurotransmission is mainly achieved through activation of gamma-aminobutyric acid (GABA) receptors. Extensive studies have established the structural and pharmacological properties of vertebrate GABA receptors. Although the vast majority of insect GABA-sensitive responses share some properties with vertebrate GABAA receptors, peculiar pharmacological properties of these receptors led us to think that several GABA-gated chloride channels are present in insects. We describe here the pharmacological properties of two GABA receptor subtypes coupled to a chloride channel on dorsal unpaired median (DUM) neurones of the adult male cockroach. Long applications of GABA induce a large biphasic hyperpolarization, consisting of an initial transient hyperpolarization followed by a slow phase of hyperpolarization that is not quickly desensitized. With GABA, the transient hyperpolarization is sensitive to picrotoxinin, fipronil and dieldrin whereas the slow response is insensitive to these insecticides.When GABA is replaced by muscimol and cis-4-aminocrotonic acid (CACA) a biphasic hyperpolarization consisting of an initial transient hyperpolarization followed by a sustained phase is evoked which is blocked by picrotoxinin and fipronil. Exposure to dieldrin decreases only the early phase of the muscimol and CACA-induced biphasic response, suggesting that two GABA-gated chloride channel receptor subtypes are present in DUM neurones. This study describes, for the first time, a dieldrin resistant component different to the dieldrin- and picrotoxinin-resistant receptor found in several insect species. [less ▲]

Detailed reference viewed: 29 (4 ULg)
Full Text
Peer Reviewed
See detailDifferential signalling through ALK-1 and ALK-5 regulates leptin expression in Mesenchymal Stem Cells
Zeddou, M.; RELIC, Biserka ULg; MALAISE, Olivier ULg et al

in Stem Cells & Development (2012), 21(11), 1948-54

Leptin plays a central role in maintaining energy balance, with multiple other systemic effects. Despite leptin importance in peripheral regulation of mesenchymal stem cells (MSC) differentiation, little ... [more ▼]

Leptin plays a central role in maintaining energy balance, with multiple other systemic effects. Despite leptin importance in peripheral regulation of mesenchymal stem cells (MSC) differentiation, little is known on its expression mechanism. Leptin is often described as adipokine, while it is expressed by other cell types. We have recently shown an in vitro leptin expression, enhanced by glucocorticoids in synovial fibroblasts. Here, we investigated leptin expression in MSC from bone marrow (BM-MSC), cord matrix (UMSC), and primary and dedifferentiated chondrocytes (DCH). Results showed that BM-MSC, but not UMSC, expressed leptin that was strongly enhanced by glucocorticoids. Interestingly, chondrocytes gained leptin expression progressively with dedifferentiation. This dedifferentiation was correlated with downregulation of ALK-5 expression, Smad2 phosphorylation (p-Smad2), and gain of ALK-1 expression and Smad1/5 phosphorylation (p-Smad1/5). TGF-β1 was shown to signal via ALK-5-Smad2/3 and/or ALK-1-Smad1/5 pathways. In BM-MSC, TGF-β1 increased p-Smad2 expression and markedly inhibited endogenous- and glucocorticoidinduced leptin expression, while ALK-5 inhibitor (SB431542) induced and restored this expression. In addition, both prednisolone and <br />SB431542 increased p-Smad1/5 expression. These results suggested ALK-5-Smad2 pathway as inhibitor of leptin expression, while ALK-1-Smad1/5 as activator. Indeed, Smad1 expression silencing induced leptin expression inhibition. Furthermore, prednisolone enhanced the expression of TGF-βRII while decreasing p-Smad2 in BM-MSC and SVF but not in UMSC. In vitro differentiation revealed differential osteogenic potential in SVF, BM-MSC and UMSC that correlates to their leptin expression potential. Our results suggest that ALK-1/ALK-5 balance regulates leptin expression in MSC. It also underlines UMSC as leptin non-producer MSC for cell therapy protocols where leptin expression is not suitable. [less ▲]

Detailed reference viewed: 66 (20 ULg)
Full Text
Peer Reviewed
See detailDifferential somatic Ca2+ channel profile in midbrain dopaminergic neurons
Philippart, Fabian ULg; Destreel, Geoffrey ULg; Merino-Sepulveda, Paulina et al

in Journal of Neuroscience (2016)

Dopaminergic (DA) neurons located in the ventral midbrain continuously generate a slow endogenous pacemaker activity, the mechanism of which is still debated. It has been suggested that, in the substantia ... [more ▼]

Dopaminergic (DA) neurons located in the ventral midbrain continuously generate a slow endogenous pacemaker activity, the mechanism of which is still debated. It has been suggested that, in the substantia nigra pars compacta (SNc), the pacemaking relies more on Ca2+ channels and that the density of L type Ca2+ channels is higher in these DA neurons than in those located in the ventral tegmental area (VTA). This might lead to a higher Ca2+ load in SNc DA neurons, and explain their higher susceptibility to degeneration. However, direct evidence for this hypothesis is lacking. We found that the L-type current and channel density is indeed higher in the somata of rat SNc DA neurons, and that this current undergoes less inactivation in this region. Non stationary fluctuation analysis (NSFA) measurements showed a much higher number of L-type channels in the soma of SNc DA neurons, as well as a smaller single channel conductance, pointing to a possible different molecular identity of L-type channels in DA neurons from the two areas. A major consequence of this is that pacemaking and even more so bursting are associated with a larger Ca2+ entry through L-type channels in SN DA neurons than in their VTA counterparts. Our results establish a molecular and functional difference between two populations of midbrain DA neurons that may contribute to their differential sensitivity to neurodegeneration. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Full Text
Peer Reviewed
See detailDifferential taurine responsiveness to ethanol in high- and low-alcohol sensitive rats : a brain microdialysis study
Quertemont, Etienne ULg; Linotte, Sylvie; De Witte, Philippe

in European Journal of Pharmacology (2002), 444(3), 143-150

Several microdialysis studies have investigated the effects of acute ethanol on extracellular amino acids in various rat brain regions, However, these studies led to conflicting results, suggesting that ... [more ▼]

Several microdialysis studies have investigated the effects of acute ethanol on extracellular amino acids in various rat brain regions, However, these studies led to conflicting results, suggesting that individual differences between rat strains and lines may play an important role. In the present study, high-alcohol sensitive (HAS) and low-alcohol sensitive (LAS) rats were used to investigate the possible relationship between ethanol sensitivity and the concentrations of extracellular amino acids in the nucleus accumbens. Several groups of HAS and LAS rats were injected with either saline or ethanol (1.0, 2.0 or 3.0 g/kg, i.p.) and the concentrations of amino acids in the nucleus accumbens microdialysates were assayed by electrochemical detection. Acute ethanol induced a dose-dependent increase in extracellular taurine concentrations. However, this increase was significantly reduced at 2,0 and 3.0 g,,kg ethanol in HAS rats relative to LAS rats. Since the biological functions of taurine suggest its implication in the reduction of ethanol adverse effects, a higher increase in taurine concentrations may contribute to the lower ethanol sensitivity of LAS rats. Although 2.0 and 3.0 g/kg ethanol did not affect extracellular glutamate concentrations, a significant increase in glutamate was observed after 1.0 g/kg ethanol to HAS rats but not to LAS rats. Such an effect remains unexplained but suggests that discrepancies between the results of previous microdialysate studies may be related to differences in the ethanol sensitivities of various rat strains. (C) 2002 Elsevier Science B.V All rights reserved. [less ▲]

Detailed reference viewed: 11 (1 ULg)
Full Text
Peer Reviewed
See detailDifferential usage of NF-kB activating signals by IL-1b and TNF-a in pancreatic beta cells
Ortis, Fernanda; Miani, M; Colli, ML et al

in FEBS Letters (2012), 586

The cytokines interleukin (IL)-1b and tumor necrosis factor (TNF)-a induce b-cell death in type 1 diabetes via NF-kB activation. IL-1b induces a more marked NF-kB activation than TNF-a, with higher ... [more ▼]

The cytokines interleukin (IL)-1b and tumor necrosis factor (TNF)-a induce b-cell death in type 1 diabetes via NF-kB activation. IL-1b induces a more marked NF-kB activation than TNF-a, with higher expression of genes involved in b-cell dysfunction and death. We show here a differential usage of the IKK complex by IL-1b and TNF-a in b-cells. While TNF-a uses IKK complexes containing both IKKa and IKKb, IL-1b induces complexes with IKKa only; this effect is achieved by induction of IKKb degradation via the proteasome. Both IKKg and activation of the TRAF6-TAK1-JNK pathway are involved in IL-1b-induced IKKb degradation. [less ▲]

Detailed reference viewed: 303 (5 ULg)
Full Text
See detailDifferentialdilatometer und dessen Anwendung bei Untersuchungen über die Entstehung der Alaune
Spring, Walthère ULg

in Berichte der Deutschen Chemischen Gesellschaft (1884), XVII

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailDifferentially abundant transcripts in PBMC of hospitalized geriatric patients with hip fracture compared to healthy aged controls
Vo, Thi Kim Duy; Godard, Patrice; de Saint-Hubert, Marie et al

in Experimental Gerontology (2011), 46

The abundance of a selection of transcript species involved in in!ammation, immunosenescence and stress response was compared between PBMC of 35 geriatric patients with hip fracture in acute phase (days ... [more ▼]

The abundance of a selection of transcript species involved in in!ammation, immunosenescence and stress response was compared between PBMC of 35 geriatric patients with hip fracture in acute phase (days 2–4 after hospitalization) or convalescence phase (days 7–10) and 28 healthy aged controls. Twenty-nine differentially abundant transcripts were identi"ed in acute phase versus healthy ageing. Twelve of these transcripts remained differentially abundant in convalescence phase, and 22 were similarly differentially abundant in acute phase of geriatric infectious diseases. Seven of these 22 transcripts were previously identi"ed as differentially abundant in PBMC of healthy aged versus healthy young controls, with further alteration for CD28, CD69, LCK, CTSD, HMOX1, and TNFRSF1A in acute phase after geriatric hip fracture and infectious diseases. The next question is whether these alterations are common to other geriatric diseases and/or preexist before the clinical onset of the diseases. [less ▲]

Detailed reference viewed: 104 (2 ULg)
Full Text
Peer Reviewed
See detailDifferentiated pellicle organization and lipopeptide production in standing culture of Bacillus subtilis strains.
Chollet-Imbert, Marlene; Gancel, Frederique; Slomianny, Christian et al

in Archives of microbiology (2009), 191(1), 63-71

Pellicle formation and lipopeptide production was analysed in standing cultures of different Bacillus subtilis strains producing two or three families of lipopeptides. Despite its ability to produce ... [more ▼]

Pellicle formation and lipopeptide production was analysed in standing cultures of different Bacillus subtilis strains producing two or three families of lipopeptides. Despite its ability to produce surfactin, B. Subtilis ATCC 6633 was unable to form stable pellicle at air-water interface. For the ATTC 21332 and ATCC 9943 strains, it was shown for the first time that the lipopeptides were also produced in standing cultures at productivities similar or lower than those obtained when the culture medium is agitated. A differentiated behaviour was observed between these strains in repetitive batch cultures. B. subtilis 9943 formed a wrinkled, thinner and more resistant pellicle than B. subtilis 21332. The structure of the pellicle determined by electron microscopy observations showed that cells of B. subtilis 9943 formed microcolonies whereas those of B. subtilis 21332 rapidly died. Under these conditions, surfactin production by strain 21332 decreased after 2 days whereas it remained stable for B. subtilis 9943 during the 6 days of the cultures. These data indicate that cells of B. subtilis strains growing in pellicle can produce lipopeptides differently depending on their cellular organisation. [less ▲]

Detailed reference viewed: 13 (1 ULg)
See detailDifferentiating between influencing factors land use and climate to assess drought effects on groundwater recharge in a temperate context
Verbeiren, Boud; Huysmans, Marijke; Vanderhaegen, Sven et al

Conference (2014, November)

Detailed reference viewed: 29 (0 ULg)
Full Text
Peer Reviewed
See detailDifferentiating muscle damage from myocardial injury by meaans of the serum creatinine kinase (CK) isoenzyme MB mass measurement/total CK activity ratio
el Allaf, M.; Chapelle, Jean-Paul ULg; El Allaf, Dia ULg et al

in Clinical Chemistry (1986), 32(2), 291-5

We immunoenzymometrically measured creatine kinase (CK) isoenzyme MB in extracts of myocardium and in homogenates of five different skeletal muscles. CK-MB concentrations in the former averaged 80.9 ... [more ▼]

We immunoenzymometrically measured creatine kinase (CK) isoenzyme MB in extracts of myocardium and in homogenates of five different skeletal muscles. CK-MB concentrations in the former averaged 80.9 micrograms/g wet tissue; in the skeletal muscles it varied widely, being (e.g.) 25-fold greater in diaphragm than in psoas. CK-MB in skeletal muscles ranged from 0.9 to 44 ng/U of total CK; the mean for myocardium was 202 ng/U. In sera from 10 trauma and 36 burn patients without myocardial involvement, maximum ratios for CK-MB mass/total CK activity averaged 7 (SEM 1) ng/U and 18 (SEM 6) ng/U, respectively. Except for an infant (220 ng/U), the highest ratio we found for serum after muscular damage was 38 ng/U. In contrast, the mean maximum ratio determined in 23 cases of acute myocardial infarction exceeded 200 ng/U. Among seven determinations performed 8 to 32 h after onset of symptoms, each infarct patient demonstrated at least one ratio greater than or equal to 110 ng/U. Ratios observed after infarct were unrelated to treatment received during the acute phase. We propose a CK-MB/total CK ratio of 80 ng/U as the cutoff value for differentiating myocardial necrosis from muscular injury. [less ▲]

Detailed reference viewed: 24 (4 ULg)