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ObjectivesInvasive fungal infections (IFIs) contribute significantly to mortality and morbidity in patients receiving myelosuppressive chemotherapy for haematological malignancies. The present study investigates the overall survival (OS), infection-related mortality and changes in treatment of IFIs in our department from 1995 until 2006.MethodsOutcomes of all chemotherapy courses were retrospectively evaluated using a standard questionnaire. Modified EORTC/MSG criteria for IFIs were applied: a positive PCR result for Aspergillus spp. in bronchoalveolar lavage was also defined as probable IFI.ResultsIn total, 1693 chemotherapy courses in 592 patients were evaluated. Sixty-three percent of chemotherapy courses were given to treat acute myeloid leukaemia, with the rest for acute lymphoblastic leukaemia or aggressive lymphoma. IFIs were observed in 139/592 patients [23.5%, 95% confidence interval (CI) 20%–27%] and in 149/1693 courses (8.8%, 95% CI 8%–10%). IFI-related mortality was 56.9% in 1995–2001 and 28.6% in 2002–06, P < 0.001. Accordingly, median OS in patients with IFI increased: 54 days (95% CI 26–82 days) in 1995–2001 versus 229 days (95% CI 35–423 days) in 2002–06, P = 0.001. By multivariate analysis, factors predictive for better OS were controlled disease after chemotherapy [hazard ratio (HR) 0.228, P < 0.001], possible IFI (in contrast to proven/probable IFI, HR 0.537, P = 0.005), age <60 years (HR 0.583, P = 0.008), time period 2002–06 (HR 0.612, P = 0.021) and use of novel antifungals (HR 0.589, P = 0.033).ConclusionsCompared with 1995–2001, IFI-related mortality decreased and OS in patients with IFI increased significantly in recent years. Improved OS was associated with controlled haematological disease, certainty of IFI diagnosis (possible), younger age, time period 2002–06 and the use of novel antifungals.

CE provides evidence of the stereoselective hydroxylation of norketamine in equinesCE with multiple isomer sulfated-CD as selector was used for the simultaneous analysis of the stereoisomers of ketamine, norketamine, 5,6-dehydronorketamine and hydroxylated metabolites of norketamine in liquid/liquid extracts of (i) in vitro incubations with ketamine or norketamine and equine liver microsomes and (ii) plasma and urine of ponies receiving a target-controlled infusion of ketamine under isoflurane anesthesia. Hydroxynorketamine metabolites with the hydroxy group at the cyclohexanone ring could be shown to be formed stereoselectively both in vitro and in vivo. Due to the lack of standard compounds, urinary extracts were fractionated by HPLC followed by characterization of the collected fractions with CE and LC-MS n with 0.7 mmu mass discrimination. Comparison of LC-MS n data obtained with the fractions, an in vitro microsomal sample, and both pony urine and hydrolyzed pony urine led to the identification of four hydroxylated norketamine metabolites with hydroxylation at the cyclohexanone ring, two with hydroxylation at the aromatic ring and four hydroxylated metabolites of ketamine. Due to the lower detection sensitivity, only the four hydroxynorketamine metabolites with hydroxylation at the cyclohexanone ring were observed by CE. The data suggest that demethylation of ketamine followed by hydroxylation of norketamine at the cyclohexanone ring is the major metabolic pathway in equine species and that the ketamine metabolism is highly stereoselective.

Prolonged impaired lung function after major abdominal surgery is not ameliorated by low tidal volume ventilation.

Enantioselective analysis of ketamine and its metabolites in equine plasma and urine by CE with multiple isomer sulfated â-CD CE with multiple isomer sulfated b-CD as the chiral selector was assessed for the simultaneous analysis of the enantiomers of ketamine and metabolites in extracts of equine plasma and urine. Different lots of the commercial chiral selector provided significant changes in enantiomeric ketamine separability, a fact that can be related to the manufacturing variability. A mixture of two lots was found to provide high-resolution separations and interference-free detection of the enantiomers of ketamine, norketamine, dehydronorketamine, and an incompletely identified hydroxylated metabolite of norketamine in liquid/liquid extracts of the two body fluids. Ketamine, norketamine, and dehydronorketamine could be unambiguously identified via HPLC fractionation of urinary extracts and using LC-MS and LC-MS/MS with 1 mmu mass discrimination. The CE assay was used to characterize the stereoselectivity of the compounds' enantiomers in the samples of five ponies anesthetized with isoflurane in oxygen and treated with intravenous continuous infusion of racemic ketamine. The concentrations of the ketamine enantiomers in plasma are equal, whereas the urinary amount of R-ketamine is larger than that of S-ketamine. Plasma and urine contain higher S-than R-norketamine levels and the mean S-/R-enantiomer ratios of dehydronorketamine in plasma and urine are lower than unity and similar.

Ketamine, an injectable anesthetic and analgesic consisting of a racemic mixture of S-and R-ketamine, is routinely used in veterinary and human medicine. Nevertheless, metabolism and pharmacokinetics of ketamine have not been characterized sufficiently in most animal species. An enantioselective CE assay for ketamine and its metabolites in microsomal preparations is described. Racemic ketamine was incubated with pooled microsomes from humans, horses and dogs over a 3 h time interval with frequent sample collection. CE data revealed that ketamine is metabolized enantioselectively to norketamine (NK), dehydronorketamine and three hydroxylated NK metabolites in all three species. The metabolic patterns formed differ in production rates of the metabolites and in stereoselectivity of the hydroxylated NK metabolites. In vitro pharmacokinetics of ketamine N-demethylation were established by incubating ten different concentrations of racemic ketamine and the single enantiomers of ketamine for 8 min and data modeling was based on Michaelis-Menten kinetics. These data revealed a reduced intrinsic clearance of the S-enantiomer in the racemic mixture compared with the single S-enantiomer in human microsomes, no difference in equine microsomes and the opposite effect in canine microsomes. The findings indicate species differences with possible relevance for the use of single S-ketamine versus racemic ketamine in the clinic.

Stereoselectivity has to be considered for pharmacodynamic and pharmacokinetic features of ketamine. Stereoselective biotransformation of ketamine was investigated in equine microsomes in vitro. Concentration curves were constructed over time, and enzyme activity was determined for different substrate concentrations using equine liver and lung microsomes. The concentrations of R/S-ketamine and R/S-norketamine were determined by enantioselective capillary electrophoresis. A two-phase model based on Hill kinetics was used to analyze the biotransformation of R/S-ketamine into R/S-norketamine and, in a second step, into R/S-downstream metabolites. In liver and lung microsomes, levels of R-ketamine exceeded those of S-ketamine at all time points and S-norketamine exceeded R-norketamine at time points below the maximum concentration. In liver and lung microsomes, significant differences in the enzyme velocity (Vmax) were observed between Sand R-norketamine formation and between Vmax of S-norketamine formation when S-ketamine was compared to S-ketamine of the racemate. Our investigations in microsomal reactions in vitro suggest that stereoselective ketamine biotransformation in horses occurs in the liver and the lung with a slower elimination of S-ketamine in the presence of R-ketamine. Scaling of the in vitro parameters to liver and lung organ clearances provided an excellent fit with previously published in vivo data and confirmed a lung first-pass effect.

Summary Purpose Intracerebral vascular malformations including cavernous angiomas (CAs) and arteriovenous malformations (AVMs) are an important cause of chronic pharmacoresistant epilepsies. Little is known about the pathogenetic basis of epilepsy in patients with vascular malformations. Intracerebral deposits of iron-containing blood products have been generally regarded as responsible for the strong epileptogenic potential of CAs. Here, we have analyzed whether blood–brain barrier (BBB) dysfunction and subsequent astrocytic albumin uptake, recently described as critical trigger of focal epilepsy, represent pathogenetic factors in vascular lesion–associated epileptogenesis. Methods We examined the correlation between hemosiderin deposits, albumin accumulation, and several clinical characteristics in a series of 80 drug-refractory epilepsy patients with CAs or AVMs who underwent surgical resection. Analysis of clinical parameters included gender, age of seizure onset, epilepsy frequency, duration of epilepsy before surgery, and postoperative seizure outcome classification according to Engel class scale. Hemosiderin deposits in the adjacent brain tissue of the vascular lesion were semiquantitatively analyzed. Fluorescent double-immunohistochemistry using GFAP/albumin costaining was performed to study albumin extravasation. Key Findings Our results suggest that a shorter duration of preoperative epilepsy is correlated with significantly better postsurgical outcome (p < 0.05), whereas no additional clinical or neuropathologic parameter correlated significantly with the postsurgical seizure situation. Intriguingly, we observed strong albumin immunoreactivity within the vascular lesion and in perilesional astrocytes (57.65 ± 4.05%), but not in different control groups. Significance Our present data on albumin uptake in brain tissue adjacent to AVMs and CAs suggests BBB dysfunction and accumulation of albumin within astrocytes as a new pathologic feature potentially associated with the epileptogenic mechanism for vascular lesions and provides novel therapy perspectives for antiepileptogenesis in affected patients.