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The physiology of the hemostatic system in children is different from that in adults. Reference ranges for components of the hemostatic system are age dependent. During early childhood, physiologic values may overlap with values observed in congenital deficiencies of acquired pathological conditions. Physiologically decreased plasma concentrations of hemostatic components also influence the response to antithrombotic therapy. The relevance of developmental hemostasis for the laboratory diagnosis and management of hemorrhagic and thrombotic disorders during childhood is discussed.

Objective: To investigate if the factor V Leiden mutation (F-V-LM) and/or the prothrombin gene G 20210 A variant (P-G20210A-V) are risk factors for acute stroke in Austrian children., Patients: 33 children with acute ischemic stroke documented by computer tomography and/or magnetic resonance imaging of the brain were enrolled in an open multicenter survey., Results: 6/33 children had F-V-LM (5 heterozygous, 1 homozygous). This represents 18% (95% CI: 6.7-39.9%) of our pediatric stroke population and thus exceeds the expected prevalence in the Austrian population of 4,6% (Fischer's exact test, p = 0.01). F-V-LM was not found in 11 children with neonatal stroke but in 6/22 children with stroke after the neonatal period. 5/6 children with F-V-LM had an underlying disorder that is a risk factor for stroke in children. The P-G20210A-V was detected in 1/26 (3.85%; 95% CI: 0.1-21.4%) patients. Comparison of the prevalence of P-G20210A-V in our study with that in the general population of Austria of 1% revealed no statistical significance (Fischer's exact test, p = 0.38)., Conclusion: Our data suggest that the F-V-LM is a risk factor for acute stroke in Austrian children beyond the neonatal period. The P-G20210A-V apparently does not represent a risk factor for stroke in Austrian children.

In a prospective study 50 children with new onset epilepsy were investigated. Routine screening for complete blood count, serum protein, albumin, gamma-glutamyltransferase (gamma-GT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, and coagulation studies before, 3, 6 and 9 weeks after commencement of antiepileptic therapy with valproate were carried out. Serum B12 and folate levels were also determined in 29 patients. The aim of the study was to evaluate the effect of VPA on these laboratory findings. We found a significant reduction of red blood count and platelet count, whereas MCV showed a significant upward trend. Vitamin B12 levels were elevated after starting VPA therapy. We found no elevations of liver enzymes, but a significant transient reduction of ALT after 3 and 6 weeks and significantly reduced serum protein and albumin after 3, 6 and 9 weeks. Coagulation studies revealed a significant downward trend in serum fibrinogen and upward trend in thrombin time. The other parameters showed no significant changes after onset of VPA treatment. We think that reduced red blood cell and platelet counts, and elevated MCV indicate a direct toxic effect on a hematopoietic precursor or stem cell in patients treated with VPA. Furthermore, reduced protein, albumin and fibrinogen indicate an impaired liver synthetic function in asymptomatic children treated with VPA monotherapy.

Our knowledge about the transfer of drugs and environmental chemicals into breast milk has increased in the last years. This review is mainly based on recently published literature and focuses on all drugs and environmental substances with documented effects on lactation and the nursing infant. Our aim is to provide brief information for physicians who are counseling breastfeeding mothers.

Clobazam 20 mg, diazepam 10 mg, lorazepam 2 mg and oxazepam 30 mg were compared in a randomized, double-blind, placebo-controlled trial as oral premedication for 150 patients undergoing minor gynaecological surgery. All drugs and placebo significantly decreased anxiety when assessed by the patient on a 10-cm linear analogue rating scale 60 min after premedication. Diazepam 10 mg induced significantly more drowsiness when assessed by a trained observer 60 min after premedication than clobazam 20 mg, oxazepam 30 mg and placebo (P less than 0.01). Lorazepam 2 mg caused significantly more drowsiness 2 h (P less than 0.001) and 4 h (P less than 0.01) after operation, and significantly impaired psychomotor function after operation compared with the other four agents. The data suggest that clobazam 20 mg, diazepam 10 mg, oxazepam 30 mg or placebo offer advantages over lorazepam 2 mg for oral premedication in minor gynaecological surgery where early discharge after operation is preferred.

Diazepam 10 and 20 mg, lorazepam 2.5 and 5.0 mg, flunitrazepam 1 and 2 mg, and a placebo, were compared in a randomized double-blind controlled trial as oral premedication for 210 patients undergoing minor gynaecological surgery. Flunitrazepam 1 mg and lorazepam 2.5 mg were superior to placebo (P less than 0.001 and P less than 0.05 respectively) in relieving patient anxiety when assessed by a trained observer 60 min after premedication. Flunitrazepam 1 mg also produced more drowsiness (P less than 0.01) than the placebo. Comparisons of other low-dose benzodiazepine groups with the placebo, and of the large dose with the small dose of each drug revealed no significant changes in anxiolysis or drowsiness. Dizziness and prolonged drowsiness were not apparent with low-dose flunitrazepam. The data suggests that flunitrazepam 1 mg offers advantages over placebo, diazepam 10 mg and lorazepam 2.5 mg for routine oral premedication in minor gynaecological surgery.

The ventilation rates of 23 operating theatres were tested randomly. These were found to vary widely from design specifications (--43 to +40%). One modern theatre was studied intensively for 6 months and the causes of poor ventilation determined. Preventative maintenance schemes are justified by a positive relationship with plant performance. The influence of theatre ventilation of contamination with anaesthetic agents and the medico-legal implications of poor theatre ventilation are discussed. There is a need for main duct airflow signals, displayed in theatre, to warn personnel of low levels of theatre ventilation.

Blood glucose levels were studied prospectively in 40 patients undergoing elective major craniotomy. A significant (p less than 0.01) hyperglycaemic response was noted after scalp infiltration with adrenaline and incision (0.5 mmol/l) and with continued surgery (0.9 mmol/l). Patients aged 50 years and under showed a significantly greater rise with adrenaline and incision than older patients (0.8 compared with 0.4 mmol/l p less than 0.01). Preoperative high dose steroid therapy did not modify the response. Blood glucose changes were unrelated to sex, obesity, a family history of diabetes, the duration of starvation, intraoperative body temperature, anaesthetic technique, induced hypotension or blood loss.

Synthesis of host-specific and phage-specific messenger ribonucleic acid (mRNA) was studied in bacteria infected by unmodified (T1 . B) or modified [T1 . B(P1)] bacteriophage T1. In a "standard" infection of Escherichia coli B by T1 . B (no host-controlled modification involved), the rate and amount of T1 mRNA synthesis was intermediate between those values reported for infections by a virulent phage such as T4 or a temperate phage such as lambda. The initial rate of mRNA synthesis was slightly increased after T1 . B(P1) infection of E. coli B in comparison with T1 . B infection of the same host. Little or no phage mRNA synthesis could be detected in T1 . B infection of E. coli B(P1). Phage mRNA synthesis in T1 . B(P1)-infected E. coli B(P1) cells was approximately the same in amount as that seen in T1 . B(P1) infection of E. coli B. Synthesis of host-specific mRNA continued throughout the latent period in all infections studied. However, the enzyme beta-galactosidase could not be induced, except after T1 . B infection of E. coli B(P1). In an attempt to understand the apparent differences in mRNA synthesis after infection of E. coli B by phages T1 . B or T1 . B(P1), the effect of altered T1 deoxyribonucleic acid (DNA) methylation on mRNA synthesis was studied. Methyl-deficient T1 DNA, made in cells infected with ultraviolet-irradiated phage T3, inhibited (14)C-uridine incorporation more strongly than normal T1. One passage of methyl-deficient T1 through E. coli B restored uracil incorporation rates to those seen with ordinary T1. This suggests that methylation of T1 DNA can influence the rate of phage mRNA synthesis. However, attempts to relate the difference in mRNA synthesis seen between T1 . B and T1 . B(P1) in E. coli B to the activity of the P1 modification gene were not conclusive.

Various properties of the bacteriophage structural dihydrofolate reductase (DFR) have been examined to determine its function during phage infection. It has been found that a binding site for reduced nicotinamide adenine dinucleotide phosphate (NADPH), most likely on the DFR present in the phage tail plate, is required for phage viability. Attachment of adenosine diphosphoribose, an analogue of NADPH, to this site prevents phage adsorption and injection. This adenosine diphosphoribose inhibition can be competitively reversed by the addition of NADPH or oxidized nicotinamide adenine dinucleotide phosphate. It is suggested that, during phage infection, the host bacterial cell might leak compounds functionally similar to the pyridine nucleotides. These compounds have been shown to nonenzymatically change the conformation of the phage tail plate DFR which is apparently necessary for successful injection.