Imaging mass spectrometry: a new way to distinguish dermal contact from administration of cocaine, using a single fingerprint

Here we show a new and significant application area for mass spectrometry imaging. The potential for fingerprints to reveal drug use has been widely reported, with potential applications in forensics and workplace drug testing. However, one unsolved issue is the inability to distinguish between drug administration and contamination by contact. Previous work using bulk mass spectrometry analysis has shown that this distinction can only be definitively made if the hands are washed prior to sample collection. Here, we illustrate how three mass spectrometry imaging approaches, desorption electrospray ionisation (DESI), matrix assisted laser desorption ionisation (MALDI) and time of flight secondary ion mass spectrometry (ToF-SIMS) can be used to visualise fingerprints at different pixel sizes, ranging from the whole fingerprint down to the pore structure. We show how each of these magnification scales can be used to distinguish between cocaine use and contact. We also demonstrate the first application of water cluster SIMS to a fingerprint sample, which was the sole method tested here that was capable of detecting excreted drug metabolites in fingerprints, while providing spatial resolution sufficient to resolve individual pore structure. We show that after administration of cocaine, lipids and salts in the fingerprint ridges spatially correlate with the cocaine metabolite, benzoylecgonine. In contrast after contact, we have observed that cocaine and its metabolite show a poor spatial correlation with the flow of the ridges.

Self-hypnosis for intrapartum pain management in pregnant nulliparous women: a randomised controlled trial of clinical effectiveness

Objective

(Primary) To establish the effect of antenatal group self-hypnosis for nulliparous women on intra-partum epidural use.

Design

Multi-method randomised control trial (RCT).

Setting

Three NHS Trusts.

Population

Nulliparous women not planning elective caesarean, without medication for hypertension and without psychological illness.

Methods

Randomisation at 28–32 weeks’ gestation to usual care, or to usual care plus brief self-hypnosis training (two × 90-minute groups at around 32 and 35 weeks’ gestation; daily audio self-hypnosis CD). Follow up at 2 and 6 weeks postnatal.

Main outcome measures

Primary: epidural analgesia. Secondary: associated clinical and psychological outcomes; cost analysis.

Results

Six hundred and eighty women were randomised. There was no statistically significant difference in epidural use: 27.9% (intervention), 30.3% (control), odds ratio (OR) 0.89 [95% confidence interval (CI): 0.64–1.24], or in 27 of 29 pre-specified secondary clinical and psychological outcomes. Women in the intervention group had lower actual than anticipated levels of fear and anxiety between baseline and 2 weeks post natal (anxiety: mean difference −0.72, 95% CI −1.16 to −0.28, P = 0.001); fear (mean difference −0.62, 95% CI −1.08 to −0.16, P = 0.009) [Correction added on 7 July 2015, after first online publication: ‘Mean difference’ replaced ‘Odds ratio (OR)’ in the preceding sentence.]. Postnatal response rates were 67% overall at 2 weeks. The additional cost in the intervention arm per woman was £4.83 (CI −£257.93 to £267.59).

Conclusions

Allocation to two-third-trimester group self-hypnosis training sessions did not significantly reduce intra-partum epidural analgesia use or a range of other clinical and psychological variables. The impact of women's anxiety and fear about childbirth needs further investigation.

Tweetable abstract

Going to 2 prenatal self-hypnosis groups didn't reduce labour epidural use but did reduce birth fear & anxiety postnatally at < £5 per woman.

[Prolonged muscle weakness in intensive care patients with special attention to the so-called intensive care polyneuromyopathy]

Generalized muscle weakness in critically ill patients can result in prolonged periods of artificial ventilation and longer stays in the intensive care unit. Both neuropathic (critical illness polyneuropathy) and myopathic (critical illness myopathy) abnormalities seem to play an important role for this prolonged weakness. This article reviews its complex differential diagnosis with special emphasis on the current understanding of the neuromuscular syndromes. An efficient diagnostic plan is necessary for the exclusion of other curable causes of prolonged muscle weakness even in the presence of polyneuromyopathic changes. Psychological support of the patient and prophylaxis of secondary complications of prolonged immobilization are crucial when specific therapy is not possible.

Novel method for detecting micro-organisms in blood cultures

A method for detecting the growth of micro-organisms in blood culture by a visual signal is described. The system utilises a single blood culture medium that has been specifically formulated to support growth of aerobic, anaerobic, and microaerophilic micro-organisms. The system is based on the principle that when micro-organisms grow in the medium in a sealed bottle their metabolic products create positive pressure. This positive pressure displaces the infected blood and broth into an upper chamber, which acts as a visual signal of microbial activity. All the test micro-organisms, when inoculated at less than 20 colony forming units into simulated human blood cultures, gave a positive signal.