Chloropicrin induces endoplasmic reticulum stress in human retinal pigment epithelial cells.

Chloropicrin is an aliphatic volatile nitrate compound that is mainly used as a pesticide. It has several toxic effects in animals and can cause irritating and other health problems in exposed humans. Since the mode of chloropicrin action is poorly understood, the aim of this study was to investigate molecular responses underlying chloropicrin toxicity. We used human retinal pigment epithelial cells (ARPE-19) as a model cell type because the eyes are one of the main target organs affected by chloropicrin exposure. Transmission electron microscopy images revealed that exposure to a chloropicrin concentration that decreased cell viability by 50%, evoked the formation of numerous electron-lucent, non-autophagy vacuoles in the cytoplasm with dilatation of the endoplasmic reticulum (ER). Lower concentrations led to the appearance of more electron-dense vacuoles, which contained cytoplasmic material and were surrounded by a membrane resembling autophagy vacuoles. According to immunoblotting analyses chloropicrin increased the amount of the ER-stress related proteins, Bip (about 3-fold compared to the controls), IRE1α (2.5-fold) and Gadd 153/Chop (2.5-fold), evidence for accumulation of misfolded proteins in the ER. This property was further confirmed by the increase of reactive oxygen species (ROS) production (2-2.5-fold), induction of heme oxygenase-1 (about 6-fold), and increase in the level of the tumour suppressor protein p53 (2-fold). Thus, the cytotoxicity of chloropicrin in the retinal pigment epithelium is postulated to be associated with oxidative stress and perturbation of the ER functions, which are possibly among the mechanisms involved in oculotoxicity of chloropicrin.

Outbreak of 2009 pandemic influenza A(H1N1) in a Finnish garrison--a serological survey.

In September 2009, an outbreak of 2009 pandemic influenza A(H1N1) took place in a Finnish garrison. In November 2009, we performed a serological survey among 984 recruits undergoing their military service at the garrison and related the results to self-reported upper respiratory tract infection (URTI) with or without fever. Of 346 volunteers who donated a blood sample, 169 (49%) had pandemic influenza A(H1N1) virus-specific antibodies. Of those, 84 (50%) reported no recent history of URTI, suggesting that a major part of those infected with pandemic influenza A(H1N1) virus may be asymptomatic.

Lack of renoprotective effect of i.v. N-acetylcysteine in patients with chronic renal failure undergoing cardiac surgery.

BACKGROUND: Pre-existing chronic renal failure is a significant risk factor for acute renal failure (ARF) after cardiac surgery. N-acetylcysteine (NAC) has been shown to prevent contrast media-induced ARF. Our objective was to evaluate whether i.v. NAC has renoprotective effects in patients with mild renal failure undergoing cardiac surgery. METHODS: In this prospective, randomized, double-blind study, 80 patients with mild to moderate renal failure undergoing elective heart surgery with cardiopulmonary bypass were recruited. All received either i.v. NAC (n=38) or placebo (n=39) at induction of anaesthesia and then up to 20 h. Urine N-acetyl-beta-D-glucosaminidase (NAG) and urine creatinine ratio, plasma creatinine, and serum cystatin C levels indicated renal function. RESULTS: Levels of urinary NAG/creatinine ratio, plasma creatinine and serum cystatin C did not significantly differ between NAC and placebo groups during five postoperative days. Urine NAG/creatinine ratio increased over 30% in 100% of patients in the NAC group vs 92.3% in the placebo group (P=0.081). Plasma creatinine increased by 25% from baseline or over 44 mumol litre(-1) in 42.1% in NAC group vs 48.7% in placebo group (P=0.560). Serum cystatin C exceeded 1.4 mg litre(-1) in 78.9% in NAC group vs 61.5% in placebo group (P=0.096). CONCLUSIONS: Prophylactic treatment with i.v. N-acetylcysteine had no renoprotective effect in patients with pre-existing renal failure undergoing cardiac surgery.

Pancytopenia induced by low-dose methotrexate. A study of the cases reported to the Finnish Adverse Drug Reaction Register From 1991 to 1999.

OBJECTIVE: To study cases of low-dose methotrexate-induced pancytopenia with special reference to clinical outcome and factors predisposing to bone marrow suppression. METHODS: Patient files of 14 cases of methotrexate-induced pancytopenia reported to the National Agency for Medicines in Finland from 1991 to 1999 were reviewed. A review of four additional cases was included. RESULTS: Of the 18 patients (median age 72 years), 12 had rheumatoid arthritis, one psoriatic arthritis, five psoriasis without arthritis, and one pemphigus erythematosus. Major co-morbidity was recorded in 12 patients, and 16 patients used significant concomitant drugs. Eight patients had a mildly or moderately elevated serum creatinine concentration. In every patient the occurrence of cytopenia was abrupt. Eight patients (44%) died, and the most frequent cause of death was infection. CONCLUSIONS: Our data show that methotrexate-induced pancytopenia is associated with high mortality especially in cases with significant co-morbidity and concomitant medications.

Randomised comparison of fluorouracil, epidoxorubicin and methotrexate (FEMTX) plus supportive care with supportive care alone in patients with non-resectable gastric cancer.

A phase III randomised study, comparing treatment with fluorouracil, epidoxorubicin and methotrexate (FEMTX) with the best supportive care, was conducted in patients with unresectable or metastatic gastric cancer. During the period from July 1986 to June 1992, 41 patients were randomised to receive FEMTX or best supportive care. MTX was given in a dose of 1500 mg m-2 intravenously (i.v.) followed after 1 h by 5-FU 1500 mg m-2 i.v. on day 1; leucovorin rescue was started after 24 h (30 mg orally every 6 h for 48 h) and epidoxorubicin 60 mg m-2 i.v. was administered on day 15. In addition both groups received tablets containing vitamins A and E. Response rates for FEMTX were as follows: complete response (CR), 19% (4/21); partial response (PR), 10% (2/21); no change (NC), 33% (7/21); and progressive disease (PD), 24% (5/21). Response rates in the control group were: NC, 20% (4/20); and PD, 80% (16/20). Increased pain was observed in one patient in the treated group and in 11 patients in the control group within the first 2 months. WHO grade III/IV toxicity in the chemotherapy group was as follows: nausea/vomiting 40%, diarrhoea 10%, stomatitis 15%, leucopenia 50% and thrombocytopenia 10%. One possible treatment-related death was due to sepsis. The median time to progression in the FEMTX group was 5.4 months [95% confidence interval (CI) 3.1-11.7 months], but only 1.7 months in the control group (95% CI 1.2-2.7 months) (P = 0.0013). Similarly, the FEMTX group displayed significantly (P = 0.0006) prolonged survival compared with the control group, i.e. median survival 12.3 months (95% CI 7.1-15.6 months) vs 3.1 months (95% CI 1.6-4.6 months). In conclusion, FEMTX combined with vitamin A and E is a fairly well-tolerated treatment, giving a response rate of 29% in patients with advanced gastric cancer, and also prolonging patients' survival. It can be used as a reference treatment in testing new investigational combinations.

Drug and ethanol effects on the clinical test for drunkenness: single doses of ethanol, hypnotic drugs and antidepressant drugs.

The clinical test for drunkenness has been used in Finland to detect alcohol-induced impairment of driving fitness. Since the data about the effects of psychotropic drugs on the clinical test for drunkenness are limited, this test was administered in two randomized double-blind cross-over trials with 12 subjects in each. The clinical tests were done at 2 hr and 5 hr after drug intake. For comparison, the representative laboratory tests used were digit symbol substitution, simulated driving (tracking+reaction time) and "global psychomotor performance". In Trial I, 15 mg of diazepam, 50 mg of amitriptyline and 15 mg of mirtazepine, each drug administered alone, had minor effects on the clinical tests. Compared to the placebo, mirtazepine, and diazepam, diazepam+mirtazepine impaired performance on the motor subtests at 2 hr. The tracking error percentage was increased by amitriptyline, diazepam+amitriptyline, and diazepam+mirtazepine up to 4.5 hr. In Trial II with 7.5 mg of zopiclone, 0.25 mg of triazolam and 0.8 g/kg of ethanol, ethanol alone and hypnotic-ethanol combinations impaired performance on the motor and vestibular subtests, whereas single drug intake had minor effects. Tracking was more sensitive to drugs than to ethanol. In conclusion, the clinical test for drunkenness detected impaired performance following single doses of ethanol or drug-ethanol combinations better than it detected impaired performance following moderate doses of drugs or drug-drug combinations, respectively.

Diazepam effects on the performance of healthy subjects are not enhanced by treatment with the antihistamine ebastine.

1. We have given 12 healthy subjects the H1-antihistamine ebastine (20 mg) or placebo in a randomized double-blind and crossover study for 1 week each. The subjects were tested for drug effects on day 6 of each period, and for interactions of ebastine with oral 15 mg diazepam (DZ) on day 7. On both days, the testing runs were at baseline and 1.5, 3, 4.5 and 6 h after intake. 2. The performance was evaluated both objectively (digit symbol substitution, flicker fusion, Maddox wing, simulated driving, body balance) and subjectively (visual analogue scales, questionnaires). Venous blood was sampled daily during the maintenance and during each testing round for the assay of plasma carebastine (the active metabolite of ebastine) by high pressure liquid chromatography and plasma diazepam by radioreceptor assay. Three-way ANOVA, paired t-test, Wilcoxon rank sign test and Fisher's fourfold table test were used for data analysis. 3. Plasma carebastine reached steady levels from day 3 onwards. The mean concentrations in the morning were 82 micrograms l-1 on day 6 and 85 micrograms l-1 on day 7. The rise (+ 150%) in plasma carebastine after an extra 20 mg ebastine was not modified by DZ. Ebastine did not affect performance objectively or subjectively, yet borderline drowsiness was recorded during the first 3 h. On day 7, plasma DZ concentrations peaked (mean 480 micrograms l-1) at 1.5 h after the intake. DZ produced impaired performance in various objective tests, and drowsiness, weakness, clumsiness, mental slowness and poor performance were reported on visual analogue scales.(ABSTRACT TRUNCATED AT 250 WORDS)

Nocturnal oxygen saturation in advanced chronic obstructive pulmonary disease after a moderate dose of ethanol.

The effect of a moderate oral dose of ethanol/(0.5 g.kg-1 body weight) on nocturnal arterial oxygen saturation (SaO2) was evaluated in nine male patients with advanced chronic obstructive pulmonary disease (COPD), (median forced expiratory volume in one second (FEV1) 0.9 l, arterial oxygen tension (PaO2) 9.3 kPa, arterial carbon dioxide tension (PaCO2) 5.3 kPa). During the four study nights (two after alcohol and two after placebo intake), the patients were monitored by whole-night computerized recordings of SaO2 (Biox-oximeter), airflow (thermistors) and respiratory as well as body movements (static charge sensitive bed). After alcohol intake, the mean blood ethanol concentration (SEM) in the evening was 42(2.3) mg.100 ml-1. Alcohol intake was associated with a marginal deterioration of nocturnal oxygenation; the mean (SEM) nocturnal SaO2 was 88.4(2.0) % after alcohol ingestion and 89.1(1.6) % after placebo ingestion, respectively. Only during the first 2 h in bed was there a statistically significant difference in SaO2 in favour of placebo (p less than 0.05). It is concluded that moderate alcohol intake in the evening, corresponding to "social" drinking, did not substantially aggravate nocturnal oxygenation in our patients with advanced COPD and mild to moderate daytime hypoxaemia.

Lack of pharmacodynamic and pharmacokinetic interactions of the antihistamine ebastine with ethanol in healthy subjects.

We have given 12 healthy subjects the H1-antihistamine ebastine (20 mg) or placebo in a double-blind, crossover study for one week each. The subjects were tested for drug effects on Day 6 of each period, and for interactions of ebastine with ethanol (0.8 g.kg-1) on Day 7. On both days, the testing runs were done at baseline and at 2, 4, and 6 h after the drug. Performance was evaluated both objectively (digit symbol substitution, flicker fusion, Madox wing, nystagmus, simulated driving, body balance) and subjectively (visual analogue scales) and with questionnaires. Venous blood samples were taken daily during maintenance and during each test run for assay of plasma carebastine. Blood ethanol concentrations were assayed with an Alcolmeter in the breath and directly in the blood. Plasma carebastine concentration reached a steady-state from Day 3 on; the mean concentrations in the morning were 92 micrograms.l-1 on Day 6 and 104 micrograms.l-1 on Day 7. The rise in plasma carebastine after an extra 20 mg of ebastine was accelerated but not increased by ethanol. Ebastine did not impair performance objectively or subjectively. It slightly improved body balance and reduced errors during simple tracking at 4 h. Blood ethanol concentrations peaked (mean 0.76 g.l-1) at 1.5 h after ethanol intake. Ethanol impaired performance in most objective tests and produced clumsiness, muzziness, and mental slowness, but little drowsiness. Ebastine neither modified the blood ethanol concentrations nor increased the effects of ethanol.(ABSTRACT TRUNCATED AT 250 WORDS)

Actions of zopiclone and carbamazepine, alone and in combination, on human skilled performance in laboratory and clinical tests.

1. Possible interactions of zopiclone and carbamazepine on human skilled performance were studied in a randomized, double-blind, crossover trial with 12 healthy young subjects. 2. Psychomotor performance (coordination, reactions, attention, cognition) and subjective effects (VAS) were measured and venous blood sampled before and 1.5, 3, 4.5 and 6 h after single oral doses of placebo, 7.5 mg of zopiclone and 600 mg of carbamazepine, which were given alone or combined. Clinical test for drunkenness (CTD) was done 2 and 5 h after drug intake. 3. Both zopiclone and carbamazepine, when administered alone, impaired performance on laboratory tests, the decrements being recorded 1.5 to 6 h after intake. In line with the plasma concentrations, the zopiclone effects peaked earlier (at 1.5 h) and lasted for a shorter time than those of carbamazepine. Zopiclone had a more pronounced effect on perceptual and cognitive functions (digit substitution) and it affected extraocular muscle tone (Maddox wing), whereas carbamazepine had stronger effects on attention. Additive pharmacodynamic actions were found in most tests after the combined treatment with zopiclone and carbamazepine. 4. CTD proved to be less sensitive than the laboratory tests in revealing drug-induced decrement of performance after administration of one agent alone. However, it revealed the combined decremental effects of zopiclone and carbamazepine. 5. When the drugs were given together, the absorption of drugs was retarded. Carbamazepine-10,11-epoxide levels were lower after intake of the drug combination than those measured after intake of carbamazepine alone. 6. The results suggest that the clinical tests developed to detect alcohol effects do not necessarily reveal drug-induced impairment of performance.

Actions and interactions of hypnotics on human performance: single doses of zopiclone, triazolam and alcohol.

Actions and interactions with ethanol (0.8 g/kg) of triazolam (TRZ, 0.25 mg) and zopiclone (ZOP, 7.5 mg) on performance and memory were studied with 12 healthy young subjects. The randomized double-blind and crossover test sessions were carried out at 1-week intervals. Each time a set of performance tests and self-assessments on visual analogue scales were done before the treatment and 1.5, 3, 4.5, 6 and 8 h after it. The clinical test for drunkenness (CTD) was done 2 and 5 h after drug intake. Venous blood was sampled after each set of tests. Both TRZ and ZOP impaired coordinative and reactive skills, but not peripheral attention or body balance. They also impaired cognitive test performance (digit substitution, symbol copying), and lowered flicker fusion threshold. The psychomotor effects of the two hypnotics and measures of subjective sedation peaked at 1.5 and 3 h. Spatial memory was impaired by TRZ at 4.5 h. Cognitive tests and tracking were most sensitive to alcohol. Furthermore alcohol impaired both motor and vestibular aspects of the CTD while both ZOP and TRZ alone had only minor effects. Alcohol enhanced and prolonged the effects of both hypnotics without modifying their plasma concentrations. Drug-alcohol interactions were mainly additive though more obvious with TRZ. Interactions were evident also on the CTD. The hypnotics were free from residual psychomotor and cognitive effects at 8 h even after the coadministration of alcohol. It is concluded that ZOP and TRZ have a mainly additive interaction with alcohol but pharmacokinetic mechanisms do not seem to contribute essentially to this.

Actions and interactions of psychotropic drugs on human performance and mood: single doses of ORG 3770, amitriptyline, and diazepam.

Actions and interactions of two antidepressants and diazepam on human skilled performance and mood were studied in a randomized double-blind cross-over trial with single oral doses of 50 mg amitriptyline (AMI), 15 mg Org 3770 (ORG) and placebo, given alone and in combination with 15 mg diazepam (DZ) to 12 young healthy subjects at one-week intervals. Objective tests (digit substitution, tapping, flicker fusion, Maddox wing, tracking, choice reactions, body sway, memory) and subjective assessments (visual analogue scale) were performed at baseline and 1.5, 3, 4.5 and 6 hours after drug administration. Side-effects were reported, blood pressure and heart rate measured and blood samples taken after each testing run. Placebo was nearly inert on performance and mood. DZ impaired some objective skills and showed sedative effects in the subjective tests. AMI produced sedation and impaired coordination as well as cognitive performance (digit substitution), most clearly at 3 to 4.5 hr. ORG resembled AMI in impairing objective and subjective performance, however, not necessarily in the same tests. Their combined effects with DZ were additive in objective tests but less additive in subjective tests. The drug combinations, but not any single drug, impaired learning acquisition. Plasma concentrations of the drugs given alone were about as expected, without important interactions. We conclude that the combinations of benzodiazepines with the antidepressants used impair skilled performance but may not cause major hazards.

Comparison of the acute physical and mental effects of ephedrine, fenfluramine, phentermine and prolintane.

Physical and mental effects of a single oral dose of ephedrine (ephedrine HCl 30 or 40 mg), fenfluramine (fenfluramine HCl 15 or 20 mg), phentermine (7.5 or 11.25 mg) and prolintane (prolintane HCl 10 or 20 mg) were compared in a double-blind placebo-controlled study. Each group consisted of 16-43 healthy volunteer medical students. The subjects fasted for at least 3 hr before drug administration and further until the end of the experiment. All the parameters were measured just prior to giving the drug, and 1.5 hr and 2.5 hr afterwards. Ephedrine significantly increased systolic blood pressure (p less than 0.05) and heart rate (p less than 0.01), whereas the other sympathomimetics affected these parameters only slightly or negligibly. None of the drugs markedly changed the tapping rate of the dominant hand. Mental activity was evaluated with a self-rating check list consisting of various mental modalities. None of the sympathomimetics significantly modified the mental activity. Memory, learning and concentration ability were evaluated with sign recording and digit span tests. In the digit span test no changes were obtained. In the sign recording test (for 3 min), phentermine increased significantly the recording score at both 1.5 hr (p less than 0.05) and 2.5 hr (p less than 0.005), and prolintane at 2.5 hr (p less than 0.05) after drug administration. The results suggest that in the doses given, which are commonly used in medical practice, ephedrine has the most pronounced cardiovascular effects, while phentermine and prolintane seem to be most active in the performance of some mental tasks.