Clinical Applications and Acute Hepatotoxicity of Intravenous Amiodarone

This cross-sectional, retrospective study was designed to evaluate the current clinical applications and acute hepatotoxicity of intravenous amiodarone administration at a hospital in China. Clinical data were collected from 1214 patients receiving intravenous amiodarone treatment between October 2003 and September 2005. Baseline patient characteristics, drug indications, administration records and acute hepatotoxicity associated with the drug were examined. Amiodarone was used primarily in arrhythmic patients with obvious cardiac dysfunction. Atrial fibrillation and ventricular arrhythmia were the two most commonly treated dysfunctions. Incorrect indications and administration methods were also noted. Hepatotoxicity occurred in 12.6% of the patients, but was mild in most cases. Males showed a higher incidence of hepatotoxicity than females. The use of amiodarone was considered to be reasonable and standardized, but there was still considerable room for improvement, particularly in the standardization of administration guidelines. Intravenous amiodarone can cause hepatotoxicity and hepatic function tests should be performed soon after giving amiodarone intravenously.

Music for medical indications in the neonatal period: a systematic review of randomised controlled trials

OBJECTIVE

To conduct a systematic review of the efficacy of music for medical indications in term or preterm neonates.

METHODS

We searched 17 electronic databases, subject bibliographies, reference lists and trials registries. Two reviewers independently screened studies for inclusion, assessed methodological quality, and extracted data. Meta-analysis was not feasible due to heterogeneity in outcomes so a qualitative analysis is presented.

RESULTS

Nine randomised trials were included. The methodological quality was generally poor (median Jadad score = 1). The outcomes most commonly reported were physiological measures (heart rate (HR), respiratory rate, oxygen saturation (SaO2)), behavioural state and pain. Six studies evaluated music for the painful procedures circumcision (three trials) and heel prick (three trials). For circumcisions, one high quality pilot study (n = 23) showed benefits of music for the outcomes of HR, SaO2 and pain, while two low quality studies showed no difference. For heel prick, three low quality studies provided some evidence that music may be beneficial primarily for measures of behaviour and pain. The remaining studies evaluated the use of music in preterm infants to improve physiological and behavioural parameters (n = 31; benefits observed for behavioural parameters), to reinforce non-nutritive sucking via use of a pacifier activated lullaby (n = 32; significant increase in feeding rates), and to influence physiological stability and behaviours in infants with chronic lung disease (n = 22; no significant differences for outcomes assessed).

CONCLUSIONS

The heterogeneity in study populations, interventions and outcomes precludes definitive conclusions around efficacy. There is preliminary evidence for some therapeutic benefits of music for specific indications; however, these findings need to be confirmed in methodologically rigorous trials.

Assessment of NMDA receptor NR1 subunit hypofunction in mice as a model for schizophrenia

N-methyl-D-aspartate receptors (NMDARs) play a pivotal role in excitatory neurotransmission, synaptic plasticity and brain development. Clinical and experimental evidence suggests a dysregulation of NMDAR function and glutamatergic pathways in the pathophysiology of schizophrenia. We evaluated electrophysiological and behavioral properties of NMDAR deficiency utilizing mice that express only 5-10% of the normal level of NMDAR NR1 subunit. Auditory and visual event related potentials yielded significantly increased amplitudes for the P20 and N40 components in NMDAR deficient (NR1(neo)-/-) mice suggesting decreased inhibitory tone. Compared to wild types, NR1(neo)-/- mice spent less time in social interactions and showed reduced nest building. NR1(neo)-/- mice displayed a preference for open arms of a zero maze and central zone of an open field, possibly reflecting decreased anxiety-related behavioral inhibition. However, locomotor activity did not differ between groups in either home cage environment or during behavioral testing. NR1(neo)-/- mice displayed hyperactivity only when placed in a large unfamiliar environment, suggesting that neither increased anxiety nor non-specific motor activation accounts for differential behavioral patterns. Data suggest that NMDAR NR1 deficiency causes disinhibition in sensory processing as well as reduced behavioral inhibition and impaired social interactions. The behavioral signature in NR1(neo)-/- mice supports the impact of impaired NMDAR function in a mouse model with possible relevance to negative symptoms in schizophrenia.

Amino acids as precursors of trihalomethane and haloacetic acid formation during chlorination

Twenty amino acids were chlorinated and examined for the formation of trihalomethane (THM) and haloacetic acid (HAA). The amino acids exhibited a high Cl(2) demand (3.4-10 mg Cl(2) mg(-1) C) but low THM formation (<4.19 microg mg(-1) C) except for tryptophan and tyrosine (45.8 - 147 microg mg(-1) C). Large variation in HAA yield occurred among the amino acids (from not detectable to 106 microg mg(-1) C). One group of amino acids, possessing chain structures, exhibited a slow increase in HAA formation (<6.2 micromol mol(-1) amino acid or <11.3 microg mg(-1) C) as the chlorine demand increased (3.4-8.9 mol Cl(2) mol(-1) amino acids). The other group of amino acids, containing ring structures (including tryptophan, tyrosine, histidine, phenylalanine, and proline) and two amino acids with chain structures (aspartic acid and asparagine), showed a fast increase in HAA formation (16-96 micromol mol(-1) amino acid or 27-106 microg mg(-1) C) with the increase in chlorine demand (5.2-15.9 mol Cl(2) mol(-1) amino acid). The ratios of TCAA to DCAA (mol/mol), derived from the amino acids, ranged between 0.01 and 1.10.

Effect of recombinant Rv1009 protein on promoting the growth of Mycobacterium tuberculosis

AIMS

To determine whether resuscitation-promoting factor (RPF) from Mycobacterium tuberculosis can promote mycobacterial growth and shorten culture time.

METHOD AND RESULTS

We cloned, expressed and purified an RPF from M. tuberculosis, Rv1009 protein and subsequently studied the biological activity of the recombinant Rv1009 (rRv1009) in liquid and on solid media. Our results indicate that the molecular weight of rRv1009 protein expressed in Escherichia coli BL21 was approximately 39 kDa. At picomolar and micromolar concentrations, rRv1009 protein could increase the optical density of freeze-dried Mycobacterium bovis BCG three to fivefold in Middlebrook 7H9 medium, stimulate the growth of viable mycobacteria on solid medium, and shorten positive growth detection time of a small number of M. tuberculosis in BACTEC 960 medium.

CONCLUSIONS

The rRv1009 could promote proliferation of mycobacteria. It may be useful for culture of mycobacteria presented in clinical samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

rRv1009 protein can be used as a growth-promoting reagent of mycobacteria in the medium to shorten the time of culture.

Pulse width effect in ultrafast laser ionization imaging

The effects of different laser pulse widths on laser-induced ionization imaging of microstructures embedded in transparent materials are investigated. It is shown that a femtosecond laser-induced ionization probe can detect the variation of elemental composition of the sample materials with a higher contrast ratio, whereas the ionization probe generated by picosecond laser pulses is more sensitive to the structural change inside optical materials, which can be well explained by the different roles of multiphoton ionization and avalanche ionization involved in material breakdown. These results also suggest that an optimum diagnosis could be obtained if well-selected laser parameters are employed in ultrafast laser ionization imaging.