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AIMS: In the Swiss heroin substitution trials, patients are treated with self-administered diacetylmorphine (heroin). Intravenous administration is not possible in patients that have venosclerosis. Earlier studies have demonstrated that oral diacetylmorphine may be used, although it is completely converted to morphine presystemically. Morphine bioavailability after high-dose oral diacetylmorphine is considerably higher than would be predicted from low-dose trials. The aim was to investigate whether the unexpectedly high bioavailability is due to a difference in the drug examined, and whether it depends on previous exposure or on dose. METHODS: Opioid-naive healthy volunteers and dependent patients from the Swiss heroin trials (n = 8 per group) received low doses of intravenous and oral deuterium-labelled morphine and diacetylmorphine, respectively. Patients also received a high oral diacetylmorphine dose. RESULTS: The maximum plasma concentration (C(max)) of morphine was twofold higher after oral diacetylmorphine than after morphine administration in both groups. However, morphine bioavailability was considerably higher in chronic users [diacetylmorphine 45.6% (95% confidence interval 40.0, 51.3), morphine 37.2% (30.1, 44.3)] than in naive subjects [diacetylmorphine 22.9% (16.4, 29.4), morphine 23.9% (16.5, 31.2)] after low oral doses (48.5 micromol) of either diacetylmorphine or morphine. Morphine clearance was similar in both groups. Moreover, oral absorption of morphine from diacetylmorphine was found to be dose dependent, with bioavailability reaching 64.2% (55.3, 73.1) for high diacetylmorphine doses (1601 micromol). CONCLUSIONS: Oral absorption of opioids is substance-, dose- and patient collective-dependent, suggesting that there may be a saturation of first-pass processes, the exact mechanism of which is not yet understood.

Many approaches were made in recent years to establish urine PCR as a diagnostic tool for Lyme borreliosis, but results are contradictory. In the present study, a standardized protocol spiking urine from healthy donors with a defined amount of whole Borrelia or Borrelia DNA was established. The development of a nested real-time PCR targeting ospA enabled a highly sensitive and quantitative analysis of these samples. We show the following. (i) Storage of spiked urine samples for up to 6 months at −20°C had no negative effect on spike recovery. (ii) Centrifugation of 10 ml of urine at 40,000 × g for 30 min resulted in a concentration of both spikes, i.e., whole Borrelia and DNA. (iii) The inhibition of DNA spike recovery in 48% (11 of 23 samples) of urine samples tested could be attributed to nuclease activity. This was abrogated by alkalizing the urine or by working with the samples on ice. Despite optimized conditions, analysis of urine samples of 12 patients with erythema migrans, the clinical stage considered to be associated with the highest bacterial load, revealed a positive result in only one sample. All 12 samples were negative by an alternative PCR targeting flagellin. The results of our study support doubts that urine is a suitable material for diagnosis of Lyme borreliosis.

In lipopolysaccharide-stimulated blood from 71 late-stage borreliosis patients, the ex vivo cytokine release capacity of tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) was reduced to 28% ± 5% and to 31% ± 5% (P≤ 0.001), respectively, compared to that of 24 healthy controls. White blood cell counts were normal in both groups. To investigate direct interactions between the pathogen and the immune cells, blood from healthy controls was exposed in vitro to live or heat-killedBorreliaor toBorrelialysate. Compared to the pattern induced by bacterial endotoxins, a reduced release of TNF-α and IFN-γ and an enhanced secretion of interleukin-10 and granulocyte colony-stimulating factor was found. In blood from 10 borreliosis patients stimulated withBorrelialysate, TNF-α formation was decreased to 31% ± 14% and IFN-γ formation was decreased to 8% ± 3% (P≤ 0.001) compared to the cytokine response of blood from healthy controls (n= 24). We propose to consider anti-inflammatory changes in the blood cytokine response capacity elicited byBorreliaas a condition that might favor the persistence of the spirochete.

The phage surface display technique was used to identify Borrelia burgdorferi antigens. By affinity selection with immunoglobulin G from pooled sera of six Lyme borreliosis (LB) patients, the ribosomal protein L25 was identified. The diagnostic value of L25 was investigated by an enzyme-linked immunosorbent assay, using sera from 80 LB patients and 75 controls, and the use of the protein resulted in a specificity of 99% and a 23% sensitivity, which qualify L25 as a useful antigen when combined with others.

Lyme disease (LD) is caused by Borrelia burgdorferi and displays different stages, including localized, early disseminated, and persistent infection, all of which are associated with profound inflammatory reactions in the host. Induction of proinflammatory cytokines by B. burgdorferi is mainly mediated by outer surface proteins interacting with TLR-2/TLR-1 heterodimers. In this study, we show that TNF-α induction by Borrelia lysate was impaired in heterozygous TLR-2 knockout mice, while reactivity to lipoteichoic acid, another TLR-2 ligand signaling via TLR-2/TLR-6 heterodimers, was unaffected. Blood from individuals heterozygous for the TLR-2 polymorphism Arg753Gln was tested for cytokine release upon stimulation with Borrelia lysate, and induction of TNF-α and IFN-γ was significantly lower as compared with individuals not exhibiting this variation. Overexpression of TLR-2 carrying the Arg753Gln polymorphism in HEK 293 cells led to a significantly stronger impairment of activation by TLR-2/TLR-1 ligands as compared with TLR-2/TLR-6 ligands. To study whether heterozygosity for the Arg753Gln variant of TLR-2 influenced susceptibility for LD, we analyzed 155 patients for this polymorphism. The Arg753Gln variant occurs at a significantly lower frequency in LD patients as compared with matched controls (5.8 vs 13.5%, odds ratio 0.393, 95% confidence interval 0.17–0.89, p = 0.033), with an even more pronounced difference when late stage disease was observed (2.3 vs 12.5%, odds ratio 0.163, 95% confidence interval 0.04–0.76, p = 0.018). These data suggest that Arg753Gln may protect from the development of late stage LD due to a reduced signaling via TLR-2/TLR-1.

Granulocyte colony-stimulating factor (G-CSF) has been in clinical use for over a decade. Its main applications are in adjunctive medication to chemotherapy and in mobilizing stem cells for bone marrow transplantation. However, it has additional effects in that it primes neutrophilic granulocytes for improved host defense, and reduces the release of pro-inflammatory cytokines. These effects have prompted trials for numerous other indications. New research into the production and regulation of G-CSF in health and disease may now enable tailored strategies to induce or boost G-CSF formation. Similarly, new forms of application may increase its effectiveness.

We investigated whether anti-inflammatory effects of treatment with granulocyte colony-stimulating factor (G-CSF, filgrastim) are mediated via prostaglandin E(2) (PGE(2)) induction. In a double-blind crossover study, 10 healthy volunteers received 300 microg of filgrastim or saline 1 week apart. This was repeated after oral administration of 50 mg of flurbiprofen 1 h before injection. The increase in neutrophilic granulocytes initiated by G-CSF was augmented significantly by flurbiprofen. Lipopolysaccharide-induced PGE(2) and thromboxane (TxB(2)) release were increased 8 h after G-CSF treatment. This increase was abrogated by flurbiprofen. However, flurbiprofen did not affect G-CSF-mediated decrease in tumor necrosis factor-alpha or interferon-gamma release. Of the volunteers treated with G-CSF, eight reported side effects (headache and bone pain) against none in the saline group. When flurbiprofen was given before injection, one volunteer each reported side effects in the G-CSF and in the saline group. These data show that G-CSF primes for increased PGE(2) and TxB(2) release. Cyclooxygenase inhibition counteracts neither the hematopoietic nor the anti-inflammatory activity of G-CSF but reduces side effects.