Biomedical subjects

C Alling

Publications and source records attributed to C Alling.

At least 37 records · Page 2Linked to original sources

PubMed1998

Determination of phosphatidylethanol in blood from alcoholic males using high-performance liquid chromatography and evaporative light scattering or electrospray mass spectrometric detection.

The 'pathologic' phospholipid, phosphatidylethanol (PEth), formed only in the presence of ethanol, was determined in extracts of human blood using high-performance liquid chromatography with evaporative light scattering detection (ELSD) or electrospray (ES) mass spectrometry. Separation was performed using a diol column and a normal-phase binary gradient system. Decreasing concentrations of PEth (15 to 1 nmol/ml blood) could be detected by ELSD in three male alcoholics, up to 3 weeks after the beginning of an alcohol-free period. Using ES, levels down to 100 pmol/ml blood was detected. The molecular species of PEth were similar to those of phosphatidylcholine found in the same blood sample. The method provides a rapid quantitative and qualitative determination of PEth in blood. The limits of detection were 200 pmol (approximately 125 ng) using ELSD and 140 fmol (approximately 100 pg) using ES, total amounts injected. ON

Alcoholism↗

PubMed1998

Significance of serum S100 release after coronary artery bypass grafting.

BACKGROUND: S100 protein has been suggested to be a serum marker for cerebral complications after cardiac operation and extracorporeal circulation. The aim of this study was to characterize the S100 release pattern after extracorporeal circulation in 515 consecutive patients undergoing coronary artery bypass grafting. METHODS: Clinical variables and outcome were prospectively registered. The cerebral outcome was determined by clinical examination. S100 was measured at the end of extracorporeal circulation, and after 5, 15, and 48 hours. RESULTS: After operation, 13 patients had stroke, 12 had delayed awakening, and 17 had encephalopathy. Early S100 release, immediately after extracorporeal circulation, was associated with age and perfusion time, but not with cerebral outcome. However, S100 release after 5 to 48 hours was associated with cerebral complications and risk factors for such outcome. Patients with stroke had higher S100 levels after 15 to 48 hours. A subset of patients with renal failure had overall higher S100 levels at 5 hours. CONCLUSIONS: Early and late S100 release indicate different mechanisms for release and emphasizes the potential power of this new biochemical marker for cerebral damage.

Adult↗

PubMed1998

Acute ethanol exposure attenuates expression of junD in human neuroblastoma cells.

This study describes the effects of acute ethanol exposure on the mRNA levels of c-jun,junB and junD in the human neuroblastoma SH-SY5Y cell line. An acute exposure to 100 mM ethanol did not influence the basal and phorbol ester-induced expression of c-jun and junB, whereas the basal mRNA level of junD was attenuated by 30%. This effect was dose- and time-dependent with maximal inhibition being detected 2 h after 100 mM ethanol treatment and the mRNA levels gradually returned towards normal afterwards. Ethanol also inhibited phorbol ester-induced expression of junD. The fact that ethanol did not influence degradation of the junD mRNA suggests that acute ethanol suppresses the transcription of the gene. These results indicate that acute ethanol exerts different effects on expression of Jun transcription factors, suggesting that as compared to c-jun and junB, the junD gene may be more sensitive to acute ethanol treatment in neuronal cells.

Dactinomycin↗

PubMed1998

Stimulation of muscarinic receptors induces expression of individual fos and jun genes through different transduction pathways.

The transduction pathways coupling muscarinic receptors to induction of fos and jun genes were investigated in neuroblastoma SH-SY5Y cells. Stimulation with carbachol induced expression of c-fos, fosB, c-jun, junB, and junD. This effect was abolished by pretreatment with atropine, indicating an involvement of muscarinic receptors. These genes were also induced by activation of protein kinase C with phorbol ester or by elevating the intracellular Ca2+ concentration with a Ca2+ ionophore. The Ca2+ effect was inhibited by KN-62, suggesting an induction through Ca2+/calmodulin-dependent kinase II. Inhibition of protein kinase C with GF109203X suppressed the carbachol-stimulated increase in mRNA levels of c-fos, fosB, and junB by approximately 70% but had only minor effects on the expression of c-jun and junD. On the other hand, preincubation with KN-62 attenuated the carbachol-induced increase in c-jun and junD expression by 70% but had no effect on c-fos, fosB, and junB mRNA levels. Simultaneous inhibition of both protein kinase C and Ca2+/calmodulin-dependent kinase II completely abolished the carbachol-stimulated expression of c-jun and junD, but c-fos, fosB, and junB were still expressed to a certain extent under this condition. Comparison of the inhibitory effects of GF109203X and Gö 6976 suggests the involvement of classical protein kinase C isozymes in muscarinic receptor-stimulated expression of fos and jun genes. These results demonstrate that the muscarinic receptor-induced expression of individual fos and jun genes is regulated via different pathways, primarily protein kinase C or Ca2+/calmodulin-dependent kinase II.

Calcium↗

PubMed1998

Ethanol exposure potentiates fosB and junB expression induced by muscarinic receptor stimulation in neuroblastoma SH-SY5Y cells.

Muscarinic receptor stimulation and activation of protein kinase C cause an increase in fosB and junB transcripts in human neuroblastoma SH-SY5Y cells. In this study, the effect of long-term ethanol exposure on these events was investigated. Carbachol-stimulated fosB and junB expression was elevated in ethanol-exposed cells compared with control cells. The potentiation was time- and dose-dependent on ethanol. Preincubation with muscarinic antagonists or protein kinase C inhibitor demonstrated that the carbachol-stimulated increase in fosB and junB mRNA levels was primarily mediated via M1 receptors and dependent on the activity of protein kinase C in both control and ethanol-exposed cells. Long-term ethanol exposure did not influence the expression of fosB and junB induced by activation of protein kinase C with phorbol ester. These results demonstrate that the muscarinic receptor-stimulated fosB and junB expression is sensitive to ethanol exposure in SH-SY5Y cells, suggesting that these genes participate in the regulation of neuronal function in response to chronic ethanol treatment.

Carbachol↗

PubMed1998

Phosphatidylethanol in blood as a marker of ethanol consumption in healthy volunteers: comparison with other markers.

Phosphatidylethanol is a "pathological" phospholipid, formed via the action of phospholipase D only in the presence of ethanol. The present study was made to elucidate how different levels and patterns of alcohol intake affect blood levels of phosphatidylethanol in comparison with other markers of abuse. We used a new HPLC-evaporative light-scattering detection technique for phosphatidylethanol quantitation. This method had a total coefficient of variation of <20% at the detection limit of 0.2 nmol, equaling 0.8 micromol/liter of whole blood. Two groups were studied. (a) Five healthy volunteers were given 32 to 47 g of ethanol in a single dose, to give blood ethanol levels of approximately 25 mmol/liter after 30 to 60 min. Phosphatidylethanol, carbohydrate-deficient transferrin (CDT), and blood ethanol were measured before and after the intake. (b) Twelve student volunteers were studied during a 3 week period of prolonged alcohol consumption (total estimated intake: 1334 +/- 488 g, mean +/- SD) and phosphatidylethanol, serum-CDT, gamma-glutamyltransferase, and blood ethanol were measured at the start of the period (day 1) and twice at the end of the period (days 18 and 21). In group (a), no phosphatidylethanol was detected at any time after ethanol dosage/intake. In group (b), no blood phosphatidylethanol or blood ethanol could be demonstrated at the start, and serum-CDT was below the discrimination limit (1.3%) in all persons. No phosphatidylethanol was detected in those four persons with the lowest intake (742 +/- 150 g). However, the remaining eight persons had detectable levels of phosphatidylethanol (1.0 to 2.1 micromol/liter), and these had a higher total intake (1630 +/- 389 g). There was a statistically significant (p = 0.02) increase in serum CDT for 3 weeks. However, only 3 of 12 persons increased above the discrimination limit. The present results indicate that a substantial alcohol intake is needed to elevate blood phosphatidylethanol. In comparison with serum-CDT, blood phosphatidylethanol appears more sensitive.

Adult↗

PubMed1997

Clinical characteristics and biological parameters in temperamental clusters of suicide attempters.

A sample of 215 suicide attempters was categorized in a cluster analysis into four groups according to temperamental trails. Monoamine metabolites in the cerebrospinal fluid were analysed (n = 106). Dexamethasone suppression tests (DST) were performed (n = 154) and the activity of the enzyme monoamine oxidase in platelets (pl-MAO) was assessed (n = 103). Patients belonging to the two clusters with the most deviant temperament profiles (nos 2 and 3) were young and scored high on the Beck Hopelessness Scale and the Suicide Assessment Scale. "Cluster 3" ("neurotic, impulsive, aggressive") patients often had dysthymia and axis II, cluster B diagnoses (e.g. borderline or histrionic personality). "Cluster 2" ("neurotic and introverted") patients often had major depression. The "Cluster 1", with on the whole a normal temperament profile, had significantly higher levels of post-DST cortisol than the other clusters. The "Cluster 4" had a normal temperament profile. Adjustment disorders were most common in "Cluster 1" and "Cluster 4". The monoamine metabolite levels did not differ between the clusters, and the differences in pl-MAO activity disappeared after adjusting for age and gender. The results suggest that temperament profiles in suicide attempters are related to psychiatric diagnoses, suicidality, hopelessness, and post-DST cortisol, but are not predictive of completed suicide.

Adolescent↗

PubMed1997

Effects of ethanol on muscarinic receptor-stimulated c-fos expression in human neuroblastoma cells.

The effect of ethanol exposure on muscarinic receptor-stimulated expression of c-fos was investigated in SH-SY5Y cells. Four days of ethanol exposure enhanced carbachol-stimulated c-fos mRNA expression, analyzed with Northern blot, and Fos/AP-1 binding activity, measured with gel mobility super shift assay. Pre-incubation with muscarinic antagonists or the protein kinase C inhibitor GF109203X demonstrated that, in both control and ethanol-treated cells, carbachol-induced c-fos expression was mediated via muscarinic M1 receptors and to a large extent through protein kinase C. However, phorbol ester-induced c-fos expression was unaffected in ethanol-treated cells. Acute exposure to ethanol caused a suppression of both carbachol- and phorbol ester-stimulated c-fos expression. These results demonstrate that muscarinic receptor-stimulated gene expression is sensitive to both acute and long-term ethanol exposure.

Carbachol↗

PubMed1997

The appearance of S-100 protein in serum during and immediately after cardiopulmonary bypass surgery: a possible marker for cerebral injury.

OBJECTIVE: To investigate the appearance and elimination of brain-specific S-100 protein in serum during and immediately after cardiopulmonary bypass. DESIGN: Prospective study. PARTICIPANTS: Twenty-nine patients undergoing elective cardiac surgery. INTERVENTIONS: Twenty-seven patients were operated on for coronary artery disease; two patients had valve replacement. Serial measurements of S-100 in arterial blood during and up to 48 hours after cardiopulmonary bypass were made. MEASUREMENTS AND MAIN RESULTS: The perioperative and postoperative course was uneventful in 25 patients, with no clinical signs of neurologic complications. S-100 was not detected before extracorporeal circulation was started. Detectable concentrations (detection limit, 0.2 microgram/L) appeared in serum after 10 minutes of perfusion and reached maximum levels, 2.43 +/- 0.3 micrograms/L, at the end of bypass. The levels then declined with elimination t1/2 of 2.2 hours. Only two patients had detectable concentrations of S-100 48 hours after the end of bypass. In four patients who developed clinical signs of cerebral injury, levels of S-100 were significantly higher at the end of bypass and 24 hours after the end of bypass. CONCLUSIONS: Cardiopulmonary bypass initiates a release of brain-specific S-100 to the systemic circulation. The release and elimination of S-100 seem to follow a reproducible pattern in patients with no signs of cerebral injury. In patients who developed cerebral injury, the concentrations of S-100 in blood were increased, thus suggesting that S-100 may be a usable marker for cerebral injury after extracorporeal circulation.

Adult↗

PubMed1997

Blood phosphatidylethanol as a marker of alcohol abuse: levels in alcoholic males during withdrawal.

Phosphatidylethanol (PEth) is formed only in the presence of ethanol, via the action of phospholipase D. We studied PEth in blood as a possible marker of alcohol abuse in 15 male alcoholics admitted for detoxification. Blood was drawn on the first day after admission and up to 28 days thereafter. PEth in whole blood was 13.2 +/- 2.2 mumol liter-1 (mean +/- SE) at first sampling and remained detectable up to 14 days after admission. Blood ethanol was 0 on the morning after admission. The time courses of PEth disappearance varied among individuals. No PEth could be found in blood of control persons who had abstained from ethanol for 4 days. Levels of PEth and carbohydrate-deficient transferrin or gamma-glutamyltranspeptidase did not correlate. Its high specificity and prolonged detectability suggest PEth in blood as a marker of recent alcohol abuse.

Adult↗

PubMed1996

Ethanol exposure increases expression of c-jun and junD in human neuroblastoma cells.

The aim of this study was to investigate the effect of ethanol exposure on the expression of fos and jun genes. Exposure of human neuroblastoma SH-SY5Y cells to ethanol for 2-4 days caused a dose-dependent increase in c-jun and junD mRNA levels, whereas mRNAs for c-fos, fosB and junB were not detectable in control or ethanol-treated cells. Four days of ethanol exposure also enhanced the AP-1 binding activity. Experiments with actinomycin D demonstrated that ethanol did not influence the degradation of c-jun and junD mRNAs. These results demonstrate that long-term exposure to ethanol increases c-jun and junD expression. This effect may be one of the mechanisms through which ethanol influences the gene regulatory system in neuronal cells.

Cell Line↗

PubMed1996

Ethanol potentiates the uptake of [14C]serine into phosphatidylserine by base-exchange reaction in NG 108-15 cells.

Phospholipid base-exchange enzymes catalyze the incorporation of nitrogenous bases into phosphoglycerides by a calcium-dependent mechanism. In this study, we describe the effect of ethanol on the incorporation of radioactive serine, choline and ethanolamine into their respective phospholipids in a neuroblastoma x glioma hybrid cell line (NG 108-15). Long term ethanol exposure induced a potentiation of the incorporation of [14C]serine into phosphatidylserine. Moreover, the phosphorus content of PS was found to be increased after long-term ethanol exposure. No concomitant changes in the phosphorus content of other phospholipids were observed. The results indicate that in NG 108-15 cells, the incorporation of radiolabelled serine into PS is potentiated during chronic ethanol exposure.

Animals↗

PubMed1996

Serum S100 protein: a potential marker for cerebral events during cardiopulmonary bypass.

BACKGROUND: There is no simple method to determine the incidence or severity of brain injury after a cardiac operation. A serum marker equivalent to cardiac enzymes is required. S100 protein leaks from the cerebrospinal fluid to blood after cerebral injury. We sought to determine the pattern of release after extracorporeal circulation (ECC). METHODS: Thirty-four patients without neurologic problems underwent coronary bypass using ECC. Four had carotid stenoses. Nine others underwent coronary bypass without ECC. Serum S100 levels were measured before, during, and after the operation. RESULTS: S100 was not detected before sternotomy. Postoperative levels of S100 were related to duration of perfusion (r = 0.89, p < 0.001). Patients who did not have ECC had undetectable or fractionally raised levels except in 1 who suffered a stroke. No patient in whom ECC was used suffered an event, but those with carotid stenosis had greater S100 levels. CONCLUSIONS: S100 protein leaks into blood during ECC and may reflect both cerebral injury and increased permeability of the blood brain barrier. S100 is a promising marker for cerebral injury in cardiac surgery if elevated levels can be linked with clinical outcome.

Aged↗

PubMed1996

Impairment of the blood-CSF barrier in suicide attempters.

In a patient group of 90 suicide attempters, 18% showed an impaired blood-CSF barrier; of these 16 patients, all but one were younger than 45 years. When compared with 105 healthy controls, a significant difference in impairment of the blood-CSF barrier, between patients and controls, was seen only in those younger than 45 years (z = -2.66; P < 0.01). Paracetamol intoxication was more common among those with an impaired blood-CSF barrier than among those without an impairment (Fisher's exact test, P = 0.00029). Paracetamol intoxication was the most common method of suicide attempt in patients with adjustment disorders. There was no significant association between alcohol and/or drug abuse and an impaired blood-CSF barrier (Fisher's exact test, P = 0.91977). There were no differences in IgG index between patients and controls. The hypothesis that a blood-CSF barrier leakage may be a confounding factor when assessing the levels of monoamine metabolites in the CSF did not receive any support.

Adult↗

PubMed1996

Aggression and personality: association with amino acids and monoamine metabolites.

Associations in 52 normal individuals were examined between plasma and cerebrospinal fluid (CSF) concentrations of tryptophan (Trp) and tyrosine, and concentrations of monoamine metabolites in the CSF, and scores on an aggression questionnaire, the Kinsey Institute Reaction List II, and the Eysenck Personality Questionnaire. There was a significantly positive correlation between CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and extroverted aggression scores, and a significantly negative correlation between CSF 5-HIAA levels and introverted aggression scores. Males showed higher plasma Trp concentrations than females, and significantly positive correlations between plasma Trp concentrations and scores on extroverted aggression and the Eysenck E scale. Males, furthermore, showed a significantly negative correlation between CSF Trp levels and scores on the Eysenck P scale, and a significantly positive correlation between concentrations of 3-methoxy-4-hydroxy-phenylglycol in CSF and scores on moral aggression. These results suggest that central serotonin influences aggression in normal individuals through effects on personality.

Adult↗

PubMed1996

Carbohydrate-deficient transferrin measured by high-performance liquid chromatography and CDTect immunoassay.

Carbohydrate-deficient transferrin (CDT) was measured in three populations using anion-exchange chromatography followed by radioimmunoassay (CDTectTM) and a new high-performance liquid chromatography (HPLC) method. The correlation between the methods in 50 consecutive clinical samples was good (r = 0.87). However, in a set of 49 samples with CDT concentrations close to the reference value of the methods, the correlation was low (r = 0.51). In addition, among controls, no correlation between the methods was found (r = 0.10). Abnormal isoforms of transferrin were noted in 5% of the clinical samples. HPLC determination of CDT offers the advantage of identifying these isoforms of transferrin and thus reducing analytical pitfalls associated with the CDTectTM method.

Adult↗

PubMed1996

Ethanol and phosphatidylethanol reduce the binding of [3H]inositol 1,4,5-trisphosphate to rat cerebellar membranes.

In this study, we have analysed the effect of ethanol and phosphatidylethanol, a unique phospholipid formed only in the presence of ethanol, on the binding of [3H]inositol 1,4,5-trisphosphate to rat cerebellar membranes. Rats were intraperitoneally injected daily with 3 g of ethanol/kg body weight for different periods of time. Repeated administration of ethanol induced a reduction in the binding capacity (Bmax) without affecting the affinity constant (Kd). A significant 32% reduction was observed after 21 days of exposure (from control Bmax values of 25 +/- 3 pmol/mg and Kd values of 9 +/- 2 nM). In an in-vitro assay, phosphatidylethanol (500 microM) and phosphatidic acid (500 microM, but no other phospholipids tested, induced a reduction in Bmax (39% and 43%, respectively). The observed effect displayed by phosphatidylethanol was not due to its degradation to phosphatidic acid or other phospholipids. The results emphasize the importance of examining phosphatidylethanol (PEth) as a possible mediator of the effects of ethanol on cellular processes. However, the role of PEth in the observed effect of long-term ethanol exposure still needs further consideration.

Animals↗

PubMed1996

Long-term exposure to ethanol increases the number and function of muscarinic M1 receptors in human neuroblastoma cells.

The effect of long-term ethanol exposure on muscarinic receptors was investigated in human neuroblastoma SH-SY5Y cells. Exposure to 100 mM ethanol for 4 days enhanced both peak and steady-state levels of carbachol-stimulated inositol 1,4,5-bisphosphate increase. An ethanol concentration of 50 mM was sufficient for an enhancement of this event. The carbachol-stimulated decrease in [3H]inositol-labeled [3H]phosphatidylnositol 4,5-bisphosphate and increase [3H]inositol trisphosphate and [3H]inositol bisphosphate were also potentiated in ethanol-treated cells, which demonstrated that the receptor-stimulated activation of phospholipase C is augmented. Experiments with pirenzepine showed that carbachol-stimulated inositol 1,4,5-trisphosphate increase is mediated via M1 receptors both in ethanol-treated and control cells. Ethanol exposure for 2 or 4 days also caused an increase in [3H]N-methylscopolamine and [3H]quinuclidinyl benzilate binding sites and elevation of [3H]pirenzepine binding, which indicated that the number of muscarinic M1 receptors is increased in ethanol-treated SH-SY5Y cells. These results demonstrate that long-term exposure to ethanol potentiates muscarinic M1 receptor-stimulated activation of phospholipase C in SH-SY5Y cells. This is likely to be explained by an increased number of muscarinic M1 receptors.

Carbachol↗