Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BAST”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Oxidative and nitrosative stress induces peroxiredoxins in pancreatic beta cells.

AIMS/HYPOTHESIS: Insulin-producing beta cells are destroyed by oxidative and nitrosative stress during the pathogenesis of Type I (insulin-dependent) diabetes mellitus. These cells are more sensitive than others due to their deficiency of well known antioxidant enzymes like superoxide dismutase, glutathione peroxidase and catalase. However the peroxiredoxins discovered in the past decade form a large family of highly conserved thioredoxin-dependent peroxide reductases, which are present in most tissues. We investigated whether peroxiredoxins I and II are present in pancreatic beta cells and if they are inducible by oxidative and nitrosative stress. METHODS: To detect these enzymes in insulin-producing beta cells we used semiquantitative RT-PCR, western blots and immunohistochemistry. The expression of peroxiredoxins I and II was analysed after treatment with cytokines, hydrogen peroxide, alloxan or streptozotocin in the rat insulinoma cells INS-1 using RT-PCR and western blots. RESULTS: We show that peroxiredoxins I and II are present in the cytoplasm of pancreatic islet cells as well as in insulinoma cell lines beta TC6-F7 and INS-1. Peroxiredoxins I and II were up-regulated by all stress agents used. CONCLUSION/INTERPRETATION: Beta cells, undersupplied with well characterized antioxidant enzymes, possess an additional antioxidant system which is inducible by oxidative as well as nitrosative stress.

Animals↗

The cuff leak test to predict failure of tracheal extubation for laryngeal edema.

OBJECTIVE: Laryngeal edema secondary to endotracheal intubation may require early re-intubation. Prior to extubation the absence of leak around an endotracheal tube may predict laryngeal edema after extubation. We evaluated the usefulness of a quantitative assessment of such a leak to identify the patients who will require early re-intubation for laryngeal edema. METHODS: This prospective study included 76 patients with endotracheal intubation for more than 12 h. The leak, in percent, was defined as the difference between expired tidal volume measured just before extubation, in volume-controlled mode, with the cuff inflated and then deflated. The best cut-off value to predict the need for re-intubation for significant laryngeal edema was determined and the patients were divided into two groups, according to this cut-off value. RESULTS: Eight of the 76 patients (11%) needed re-intubation for laryngeal edema. Patients requiring re-intubation had a smaller leak than the other patients [9 (3-18) vs 35 (13-53)%, p<0.01]. The best cut-off value for gas leak was 15.5%. The high leak group included 51 patients, of whom only two patients (3%) required re-intubation. The low leak group included 25 patients, among whom six patients (24%) required re-intubation ( p<0.01). The sensitivity of this test was 75%, the specificity 72.1%, the positive predictive value 25%, the negative predictive value 96.1% and the percent of correct classification 72.4%. CONCLUSIONS: A gas leak around the endotracheal tube greater than 15.5% can be used as a screening test to limit the risk of re-intubation for laryngeal edema.

Aged↗

Permethrin absorption not detected in single-pass perfused rabbit ear, and absorption with oxidation of 3-phenoxybenzyl alcohol.

Isolated rabbit ears were single-pass perfused with a protein-free medium. Permethrin (0.05-23.5%, w/w) was applied in four distinct ointments. Permethrin, 3-phenoxybenzyl alcohol, 3-phenoxybenzaldehyde, and 3-phenoxybenzoic acid were analysed by HPLC. Permethrin was not detected in the effluent. The permeation coefficient, calculated from the detection limit was < 7.3 x 10(-12) (cm/sec). The appearance rate of the 3-phenoxybenzyl moieties in the effluent agreed with the absorption of the corresponding impurities in the various ointments. In supernatant of homogenised skin, the hydrolysis rate of permethrin was linear; about 4 pmol/min per cm2 at 10 microM substrate concentration. The proportion of 3-phenoxybenzoic acid, a further metabolite of 3-phenoxybenzyl alcohol increased when an oxidizing co-factor system was added. The appearance rate in the effusate of 3-phenoxybenzyl alcohol following the lipophobic ointment was five times faster than from isopropyl myristate. The formation rate of 3-phenoxybenzoic acid followed saturation kinetics. Occupational systemic poisoning by dermal absorption of permethrin seems very unlikely since humans bear more epithelial cell layers than rabbits. These experiments do not contradict, however, possible paraesthesia during systemic poisoning after inhalation or ingestion of the pyrethroid-containing aerosols used in agriculture.

Animals↗

Investigating transport proteins by solid state NMR.

Transporters form an interesting and complex class of membrane proteins. Many of them are potential drug targets due to their role in translocation of ions, small molecules and peptides across the membrane or due to their role in multidrug resistance. Hence elucidating their structure and mechanism is of great importance and may lead to a host of new drugs and methods to alter or inhibit their function. Solid state NMR is an emerging technique for investigating transport proteins. Along with other biochemical and biophysical techniques solid state NMR can provide data on drug binding, protein dynamics and structure at the interface between structural biology and functional analysis. Here, we review solid state NMR applications to primary active and secondary transporters involved in translocation of small molecules. We discuss current experimental limitations and give an overall perspective on how the technique may be used to address some pertinent questions relevant to transporters.

Amino Acid Sequence↗

Hyperactivity, decreased startle reactivity, and disrupted prepulse inhibition following disinhibition of the rat ventral hippocampus by the GABA(A) receptor antagonist picrotoxin.

RATIONALE: Functional imaging studies have revealed overactivity of the hippocampus in schizophrenic patients. Neuropathological data indicate that hyperactivity of excitatory hippocampal afferents and decreased hippocampal GABA transmission contribute to this overactivity. In rats, excitation of the ventral hippocampus, e.g. by NMDA, results in hyperactivity and disruption of sensorimotor gating measured as prepulse inhibition (PPI) of the acoustic startle response, behavioral effects related to psychotic symptoms in humans. OBJECTIVE: The present study examined whether disinhibition of the ventral hippocampus by the GABA(A) antagonist picrotoxin would result in similar psychosis-related behavioral disturbances (hyperactivity, decreased PPI) as NMDA stimulation. METHODS AND RESULTS: Wistar rats received bilateral infusions of subconvulsive doses of picrotoxin (100 or 150 ng/0.5 microl per side) into the ventral hippocampus and were then immediately tested for open field locomotor activity or startle reactivity and PPI. Only the higher dose induced hyperactivity and decreased PPI. Both doses decreased acoustic startle reactivity to a similar extent. The decreased PPI appeared not to result from decreased startle reactivity, but was associated with a diminished potency of the prepulses to inhibit the startle reaction to the startle pulse, indicating a sensorimotor gating deficit. All effects were temporary, i.e. disappeared when the rats were tested 24 h after infusion. CONCLUSIONS: Decreased GABAergic inhibition in the ventral hippocampus of rats yielded psychosis-related behavioral effects, very similar to those induced by NMDA stimulation. Thus, a concurrence of decreased GABAergic inhibition and increased afferent excitation in the hippocampus of schizophrenic patients might contribute to psychotic symptoms.

Animals↗

The ventral hippocampus and fear conditioning in rats. Different anterograde amnesias of fear after tetrodotoxin inactivation and infusion of the GABA(A) agonist muscimol.

Studies on the involvement of the rat hippocampus in classical fear conditioning have focused mainly on the dorsal hippocampus and conditioning to a context. However, the ventral hippocampus has intimate connections with the amygdala and the nucleus accumbens, which are involved in classical fear conditioning to explicit and contextual cues. Consistently, a few recent lesion studies have indicated a role for the ventral hippocampus in classical fear conditioning to explicit and contextual cues. The present study examined whether neuronal activity within the ventral hippocampus is important for the formation of fear memory to explicit and contextual cues by classical fear conditioning. Tetrodotoxin (TTX; 10 ng/side), which completely blocks neuronal activity, or muscimol (1 microg/side), which increases GABA(A) receptor-mediated inhibition, were bilaterally infused into the ventral hippocampus of Wistar rats before the conditioning session of a classical fear-conditioning experiment. Conditioning to a tone and the context were assessed using freezing as a measure of conditioned fear. TTX blocked fear conditioning to both tone and context. Muscimol only blocked fear conditioning to the context. The data of the present study indicate that activity of neurons in the ventral hippocampus is necessary for the formation of fear memory to both explicit and contextual cues and that neurons in the ventral hippocampus that bear the GABA(A) receptor are important for the formation of fear conditioning to a context. In addition, both bilateral muscimol (0.5 microg/side and 1 microg/side) and TTX (5 ng/side and 10 ng/side) infusion into the ventral hippocampus dose-dependently decreased locomotor activity in an open-field experiment.

Acoustic Stimulation↗

Comparison of several approaches of therapeutic drug monitoring of cyclosporin A based on individual pharmacokinetics.

OBJECTIVE: The clinical outcome of patients after organ transplantation is correlated with cyclosporin A (CyA) exposure. It is generally accepted that the area under the concentration-time curve (AUC) provides a reliable means for drug exposure. However, in routine therapeutic drug monitoring (TDM) of CyA, trough levels are mostly used. Currently, a number of different new concepts of CyA-TDM, including approaches such as single, double or triple time-point and abbreviated AUC determinations, have been introduced. The purpose of this study was to compare the predictive value of the different strategies of TDM. METHODS: Calculations were based on 40 individual concentration time profiles after oral administration of CyA to patients who had been included into an ongoing prospective clinical trial. Non-compartmental analysis was used to calculate the AUC0-12h. Multiple linear regression was performed to describe the relationship between the different sets of blood concentrations and the respective AUC0-12h as well as to evaluate their predictive value regarding AUC. Predictive performance was assessed by prediction bias and prediction precision, which were estimated as the mean prediction error and root mean squared error, respectively. RESULTS: When comparing the various combinations of time points, it was found that one-point approaches showed the strongest differences with regard to the predictive value; the associated r2 values differed from 0.203 to 0.792. The two and three time-point approaches showed lower differences - r2 0.802-0.972. The four-point and five-point approaches (r2 0.942-0.982) were the strongest predictors for CyA AUC0-12h. Relative bias ranged from -27.7% to 63.8% and changed significantly when multiple-point predictors were used. In those cases, the predictive performance improved. Considering the predictive performance as well as the smallest bias and highest prediction precision, C3, C1 + C3, C1 + C3 + C6 and C1 + C2 + C3 + C6 were the best predictors. CONCLUSION: The results of this study indicate that in kidney transplant patients a clinically sufficient precise estimation of the CyA AUC is possible using two or three concentration time points.

Adult↗

Preclinical validation of the hypoxia tracer 2-(2-nitroimidazol-1-yl)- N-(3,3,3-[(18)F]trifluoropropyl)acetamide, [(18)F]EF3.

The 2-nitroimidazole derivative 2-(2-nitroimidazol-1-yl)- N-(3,3,3-trifluoropropyl)acetamide (EF3) is a marker which forms adducts into hypoxic cells. Radiosynthesis of [(18)F]EF3 was recently performed by our group. Our aim was to study the pharmacokinetics, biodistribution, metabolism and specificity for hypoxia of [(18)F]EF3. MCa-4, SCC VII, NFSA, FSA, FSA II or Sa-NH tumour-bearing C3H mice were injected intravenously with [(18)F]EF3 and allowed to breathe air, 10% O(2) or carbogen until sacrifice 5-770 min after injection. Radioactivity was measured ex vivo in various organs, including urine and faeces. Selected organs were additionally processed to measure tracer metabolites with high-performance liquid chromatography. The half-life in blood was 73.9 min. [(18)F]EF3 was eliminated mainly via the kidneys, with 75% of the injected activity found in the urine by 12 h 50 min. The biodistribution was fast and homogeneous except in the brain and the bone, where it was significantly lower, and in the liver and the kidney, where it was significantly higher. In most organs, the exceptions being the gastrointestinal and urinary tract, tissue-to-blood ratios were below or close to unity. In tumours, a relative accumulation of the tracer was observed with time, which, at 220 min after injection, depended on tumour strain and oxygenation conditions, i.e. 10% O(2) significantly increased the tumour-to-muscle ratio whereas carbogen decreased it. [(18)F]EF3 was rapidly metabolised in the kidney and the liver. [(18)F]EF3 is a promising tracer for detection of tumour hypoxia. A phase I study in head and neck cancer patients is in progress at our institution.

Animals↗

Detection of tumour hypoxia: comparison between EF5 adducts and [18F]EF3 uptake on an individual mouse tumour basis.

In the framework of the preclinical validation of the hypoxic tracer [(18)F]EF3, a comparison was performed between uptake of [(18)F]EF3 and EF5 adducts detected by immunofluorescence in MCa-4, FSA, FSAII, Sa-NH and NFSA tumour-bearing mice. Mice were allowed to breath carbogen (5% CO(2), 95% O(2)), 21% oxygen or 10% oxygen. A significant correlation (r (2)=0.57; p<0.01) was found between the [(18)F]EF3 tumour-to-muscle ratio and the fluorescence intensity of EF5.

Animals↗

Efficacy and toxicity of plasma-cell-reactive monoclonal antibodies B-B2 and B-B4 and their immunotoxins.

Immunotherapy based on the delivery of toxic agents to the tumor site using monoclonal antibodies (mAb) may be a promising modality in the treatment of hematological malignancies. In the selection of mAb, both for ex vivo but even more for in vivo therapy, not only their reactivity to the neoplastic cells should be considered, but also reactivity to other body constituents. Here we describe the screening of two human plasma-cell-reactive mAb B-B2 and B-B4, which may be used for immunotherapy of multiple myeloma. Cross-reactivity of B-B2 and B-B4 was determined by immunohistochemistry on a series of tissues. This revealed for both B-B2 and B-B4 a strong staining of epithelial cells in various organs, e.g. lung, liver, skin, kidney and gut, while only a weak and diffuse staining was seen with endothelial cells. In bone marrow reactivity was only found with plasma cells and not with hemopoietic precursors (CD34+ cells). Immunotoxins from B-B2 and B-B4 were constructed by coupling them to the plant-derived ribosome-inactivating protein saporin. Both B-B2 and B-B4 immunotoxins appeared to be efficient in specific inhibition of protein synthesis in plasma cell lines (IC50 respectively 1 nM and 0.1 nm). The immunotoxins were also tested on epithelial cell line A431, on liver cell line HepG2 and on human umbilical vein endothelial cells. The epithelial cell line A431 was reactive with both B-B2 and B-B4, but was only inhibited by B-B4 immunotoxin. Cell line HepG2 was reactive with both mAb, but was not inhibited by either immunotoxin. The endothelial cells showed no reactivity with B-B2 and B-B4 and were not inhibited by either immunotoxin. Bone marrow treated with B-B2 and B-B4 immunotoxin did not show a decrease in colonies of hemopoietic precursor cells. Incubation of multiple-myeloma-derived bone marrow with these immunotoxin resulted in a clear decrease of the number of plasma cells. From these data we conclude that B-B2 and B-B4 immunotoxin can be used for ex vivo bone marrow purging. Discrepancies were found between immunohistochemistry, binding assays and cytotoxicity assays with the mAb and the immunotoxin, which underlines the necessity for these various assays as a preclinical screening.

Antibodies, Monoclonal↗

The cardioprotector monoHER does not interfere with the pharmacokinetics or the metabolism of the cardiotoxic agent doxorubicin in mice.

PURPOSE: Monohydroxyethylrutoside (monoHER) has proved to be a good protector against doxorubicin-induced cardiotoxicity without interfering with the antitumor effect of doxorubicin. The aim of the present study was to determine whether there is a pharmacokinetic interaction between monoHER and doxorubicin which may be involved in monoHER cardioprotection. METHODS: Mice were treated with monoHER (500 mg x kg(-1) i.v.) alone, monoHER 5 min after doxorubicin (10 mg x kg(-1) i.v.), doxorubicin alone and doxorubicin 5 min after monoHER. The levels of monoHER and doxorubicin(ol) in plasma and heart tissue were measured by HPLC 24 h and 48 h after monoHER and doxorubicin administration, respectively. RESULTS: The areas under the concentration-time curves (AUCs) of monoHER and doxorubicin(ol) were not affected by the coadministered drug. No changes were observed in pharmacokinetic parameters such as initial and final half-lives, mean residence time, clearance and volume of distribution of monoHER and doxorubicin(ol) after single or combined administration. CONCLUSION: The cardioprotection of monoHER in mice is not caused by a pharmacokinetic interaction between monoHER and doxorubicin.

Animals↗

Bioavailability and pharmacokinetics of the cardioprotecting flavonoid 7-monohydroxyethylrutoside in mice.

PURPOSE: The pharmacokinetics and bioavailability of monoHER, a promising protector against doxorubicin-induced cardiotoxicity, were determined after different routes of administration. METHODS: Mice were treated with 500 mg.kg(-1) monoHER intraperitoneally (i.p.), subcutaneously (s.c.) or intravenously (i.v.) or with 1000 mg.kg(-1) orally. Heart tissue and plasma were collected 24 h after administration. In addition liver and kidney tissues were collected after s.c. administration. The levels of monoHER were measured by HPLC with electrochemical detection. RESULTS: After i.v. administration the AUC(0-120 min) values of monoHER in plasma and heart tissue were 20.5+/-5.3 micromol.min.ml(-1) and 4.9+/-1.3 micromol.min.g(-1) wet tissue, respectively. After i.p. administration, a mean peak plasma concentration of about 130 microM monoHER was maintained from 5 to 15 min after administration. The AUC(0-120 min) values of monoHER were 6.1+/-1.1 micromol.min.ml(-1) and 1.6+/-0.4 micromol.min.g(-1) wet tissue in plasma and heart tissue, respectively. After s.c. administration, monoHER levels in plasma reached a maximum (about 230 microM) between 10 and 20 min after administration. The AUC(0-120 min) values of monoHER in plasma, heart, liver and kidney tissues were 8.0+/-0.6 micromol.min.ml(-1), 2.0+/-0.1, 22.4+/-2.0 and 20.5+/-5.7 micromol.min.g(-1), respectively. The i.p. and s.c. bioavailabilities were about 30% and 40%, respectively. After oral administration, monoHER could not be detected in plasma, indicating that monoHER had a very poor oral bioavailability. CONCLUSIONS: MonoHER was amply taken up by the drug elimination organs liver and kidney and less by the target organ heart. Under cardioprotective conditions (500 mg/kg, i.p.), the Cmax was 131 microM and the AUC(infinity) was 6.3 microM.min. These values will be considered endpoints for the clinical phase I study of monoHER.

Administration, Oral↗

A phase I study of monohydroxyethylrutoside in healthy volunteers.

The flavonol monohydroxyethylrutoside (monoHER) has demonstrated protection against doxorubicin-induced cardiotoxicity in in vitro and in vivo studies without affecting the antitumor effect. In the present phase I study, the possible side effects and the pharmacokinetics of monoHER were evaluated in healthy volunteers with the aim to develop a safe and feasible dose to be evaluated in cancer patients treated with doxorubicin. The study was performed as a single blind, randomized trial in healthy volunteers (age between 19 and 56 years). At each dose level, six subjects received monoHER and three placebo. MonoHER was solubilized in 100 ml dextrose 5% and administered as an i.v. infusion in 10 min. The placebo consisted of 100 ml dextrose 5%. The starting dose of monoHER was 100 mg/m(2). Dose escalation by 100% of the preceding dose took place after finishing each dose level until the protecting pharmacokinetic values for C (max) and AUC(infinity) (as observed in mice after 500 mg/kg monoHER i.p.) were reached and/or serious side effects were observed. The dose was escalated up to 1,500 mg/m(2). The mean values of C (max) and AUC(infinity) were 360+/-69.3 microM and 6.8+/-2.1 micromol min/ml, respectively. These values were comparable to the C (max) and AUC(infinity) observed under the protecting conditions in mice. No serious side effects occurred during the entire study. Thus, 1,500 mg/m(2) is a feasible and safe dose to be evaluated in a phase II study to investigate the protective properties of monoHER against doxorubicin-induced cardiotoxicity in cancer patients.

Adolescent↗

The influence of the time interval between monoHER and doxorubicin administration on the protection against doxorubicin-induced cardiotoxicity in mice.

PURPOSE: Despite its well-known cardiotoxicity, the anthracyclin doxorubicin (DOX) continues to be an effective and widely used chemotherapeutic agent. DOX-induced cardiac damage presumably results from the formation of free radicals by DOX. Reactive oxygen species particularly affect the cardiac myocytes because these cells seem to have a relatively poor antioxidant defense system. The semisynthetic flavonoid monohydroxyethylrutoside (monoHER) showed cardioprotection against DOX-induced cardiotoxicity through its radical scavenging and iron chelating properties. Because of the relatively short final half-life of monoHER (about 30 min), it is expected that the time interval between monoHER and DOX might be of influence on the cardioprotective effect of monoHER. Therefore, the aim of the present study was to investigate this possible effect. METHODS: Six groups of 6 BALB/c mice were treated with saline, DOX alone or DOX (4 mg/kg i.v.) preceded by monoHER (500 mg/kg i.p.) with an interval of 10, 30, 60 or 120 min. After a 6-week treatment period and additional observation for 2 weeks, the mice were sacrificed. Their cardiac tissues were processed for light microscopy, after which cardiomyocyte damage was evaluated according to Billingham (in Cancer Treat Rep 62(6):865-872, 1978). Microscopic evaluation revealed that treatment with DOX alone induced significant cardiac damage in comparison to the saline control group (P<0.001). RESULTS: The number of damaged cardiomyocytes was 9.6-fold (95% CI 4.4-21.0) higher in mice treated with DOX alone than that in animals of the control group. The ratio of aberrant cardiomyocytes in mice treated with DOX preceded by monoHER and those in mice treated with saline ranged from 1.6 to 2.8 (mean 2.2, 95% CI 1.2-4.1, P=0.019). The mean protective effect by adding monoHER before DOX led to a significant 4.4-fold reduction (P<0.001, 95% CI 2.3-8.2) of abnormal cardiomyocytes. This protective effect did not depend on the time interval between monoHER and DOX administration (P=0.345). CONCLUSION: The results indicate that in an outpatient clinical setting monoHER may be administered shortly before DOX.

Animals↗

Long-term effects of 7-monohydroxyethylrutoside (monoHER) on DOX-induced cardiotoxicity in mice.

Doxorubicin (DOX) is a potent antitumor agent for different types of cancer, but the cumulative, dose-related cardiotoxicity limits its clinical use. The incidence of abnormal cardiac function after treatment with DOX appears to increase with time. Therefore, late cardiotoxicity is-especially in young surviving patients-a major concern. The aim of this study was to evaluate in mice whether the semisynthetic flavonoid 7-monohydroxyethylrutoside (monoHER) also protected against DOX-induced cardiotoxicity after a long period of follow-up. Four groups of 6 Balb/c mice were treated weekly during 6 weeks with saline, DOX alone (4 mg/kg i.v.), DOX preceded by monoHER (500 mg/kg i.p.), or DOX preceded by monoHER followed by long-term weekly monoHER injections during the observation period of 6 months. Half of the mice treated with DOX only developed DOX-induced heart failure and died within 6 months of observation. Two mice co-treated with monoHER showed weight loss and shortness of breath, whereas one mouse was found dead in its cage known with weight loss. The group receiving DOX plus long-term repeated doses of monoHER started to lose weight. Five out of six mice in this group developed shortness of breath and died before the end of the study with symptoms of cardiac failure induced by DOX. Statistical comparison of the histological heart damage between the different experimental groups was not possible, because the animals died at different time-points in the observation period and DOX-induced cardiotoxicity progressed with time. Nevertheless, it was clear that the initial cardioprotective effect of monoHER was not prolonged during the half-year observation period. It was even suggested that addition of repeated doses of monoHER tended to aggravate DOX-induced cardiotoxicity. It cannot be excluded that the dose and frequency of monoHER administration is crucial in obtaining an optimal antioxidant activity without a pro-oxidant activity of monoHER.

Animals↗

Doxorubicin-induced cardiotoxicity monitored by ECG in freely moving mice. A new model to test potential protectors.

In laboratory animals, histology is most commonly used to study doxorubicin-induced cardiotoxicity. However, for monitoring during treatment, large numbers of animals are needed. Recently we developed a new method to measure ECG values in freely moving mice by telemetry. With this model we investigated the effect of chronic doxorubicin administration on the ECG of freely moving BALB/c mice and the efficacy of ICRF-187 as a protective agent. The ST interval significantly widened from 15.0 +/- 1.5 to 56.8 +/- 11.8 ms in week 10 (7 weekly doses of 4 mg/kg doxorubicin given i.v. plus 3 weeks of observation). The ECG of the control animals did not change during the entire study. After sacrifice the hearts of doxorubicin-treated animals were enlarged and the atria were hypertrophic. As this schedule exerted more toxicity than needed to investigate protective agents, the protection of ICRF-187 was determined using a dose schedule with lower general toxicity (6 weekly doses of 4 mg/kg doxorubicin given i.v. plus 2 weeks of observation). On this schedule, the animals' hearts appeared normal after sacrifice and ICRF-187 (50 mg/kg given i.p. 1 h before doxorubicin) provided almost full protection. These data were confirmed by histology. The results indicate that this new model is very sensitive and enables monitoring of the development of cardiotoxicity with time. These findings result in a model that allows the testing of protectors against doxorubicin-induced cardiotoxicity as demonstrated by the protection provided by ICRF-187.

Analysis of Variance↗

Hyponatraemia in children with acute CNS disease: SIADH or cerebral salt wasting?

Hyponatraemia in patients with an acute central nervous system disease can be caused by two different mechanisms: (1) retention [corrected] of free water, i.e. the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and (2) excessive sodium retention [corrected], i.e., the cerebral salt wasting syndrome (CSW). Although the concept of CSW is well known in adult medicine, it is still not established in child neurology. We conducted a retrospective analysis of electrolyte disturbances in 195 children with various acute CNS diseases. In 20 children (10.3%) hyponatraemia with plasma sodium below 130 mmol/l was identified. On the basis of clinical and laboratory data 7 of these 20 children were diagnosed as having SIADH, and the other 9 children, as having CSW. Our data suggest that hyponatraemia attributable to CSW is at least as frequent in children as SIADH. Because of their different pathophysiological mechanisms, which require diametrically opposed therapeutic regimens, early differential diagnosis is mandatory if the correct treatment is to be given.

Acute Disease↗