Invading slugs (Arion vulgaris) can be vectors for Listeria monocytogenes

AIMS

Listeriosis is a frequent silage-associated disease in ruminants. The slugs Arion vulgaris are invaders in gardens, vegetable crops and meadows for silage production. Field and laboratory studies were conducted to clarify whether slugs could host Listeria monocytogenes and thereby constitute a threat to animal feed safety.

METHODS AND RESULTS

Selective culture of L. monocytogenes from 79 pooled slug samples (710 slugs) resulted in 43% positive, 16% with mean L. monocytogenes values of 405 CFU g(-1) slug tissues. Of 62 individual slugs cultured, 11% also tested positive from surface/mucus. Multilocus sequence typing analysis of 36 isolates from different slug pools identified 20 sequence types belonging to L. monocytogenes lineages I and II. Slugs fed ≅4·0 × 10(5)  CFUL. monocytogenes, excreted viable L. monocytogenes in faeces for up to 22 days. Excretion of L. monocytogenes decreased with time, although there were indications of a short enrichment period during the first 24 h.

CONCLUSIONS

Arion vulgaris may act as a vector for L. monocytogenes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Highly slug-contaminated grass silage may pose a potential threat to animal feed safety.

Self-reported recurrent pain and medicine use behaviours among 15-year olds: results from the international study

BACKGROUND

There is considerable variation in adolescent pain prevalence across epidemiological studies, with limited information on pain-related behaviours among adolescents, including medicine use. The aims of this study were (1) to examine the prevalence of recurrent pain among 15-year-old adolescents internationally; (2) to investigate the association between recurrent pain and medicine use behaviours among boys and girls; and (3) to evaluate the consistency of these associations across countries.

METHODS

The World Health Organization (WHO) collaborative international Health Behaviour in School-aged Children 2009/2010 study collects data about self-reported aches and medicine use from 36,762 15-year-old adolescents from 22 countries/regions in Europe and the United States. Multi-level multivariate logistic regression, stratified by gender, was used to analyse the association between recurrent pain and medicine use for headache, stomachache, nervousness and difficulties in getting to sleep.

RESULTS

More than 30% of adolescents reported recurrent headache, almost 30% recurrent backache and approximately 20% recurrent stomachache. Although pain prevalence and medicine use for aches were much higher for girls, the association between pain and medicine use was similarly strong for both genders. Adolescents with recurrent pain are more likely to use medicines also for non-corresponding pain, nervousness and difficulties in getting to sleep. The association between recurrent pain and medicine use was consistent across countries despite large-country differences in the prevalence of recurrent pain and medicine use.

CONCLUSIONS

Recurrent pain in adolescence is common cross-nationally. Adolescents with recurrent pain are more likely to use medicine in general. Recurrent pain and medicine use should be addressed in adolescent health policies.

Cortical glutamate levels decrease in a non-human primate model of dopamine deficiency

While Parkinson's disease is the result of dopaminergic dysfunction of the nigrostriatal system, the clinical manifestations of Parkinson's disease are brought about by alterations in multiple neural components, including cortical areas. We examined how 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration affected extracellular cortical glutamate levels by comparing glutamate levels in normal and MPTP-lesioned nonhuman primates (Macaca mulatta). Extracellular glutamate levels were measured using glutamate microelectrode biosensors. Unilateral MPTP-administration rendered the animals with hemiparkinsonian symptoms, including dopaminergic deficiencies in the substantia nigra and the premotor and motor cortices, and with statistically significant decreases in basal glutamate levels in the primary motor cortex on the side ipsilateral to the MPTP-lesion. These results suggest that the functional changes of the glutamatergic system, especially in the motor cortex, in models of Parkinson's disease could provide important insights into the mechanisms of this disease.

Gels and threads: mussel-inspired one-pot route to advanced responsive materials

Self-healing hydrogels are obtained in a one-pot reaction between tannic acid, trivalent metal ions and polyallylamine. At high concentrations, meter-long threads could be drawn from low pH solutions.

Adherence to isoniazid preventive therapy in children exposed to tuberculosis: a prospective study from Guinea-Bissau

OBJECTIVE

To assess adherence to isoniazid preventive therapy (IPT) in children exposed to adult pulmonary tuberculosis (TB) at home.

METHODS

Children were enrolled on IPT if they were aged ≤ 5 years or 5-15 years and presented a tuberculin skin test induration of ≥ 10 mm. Children were included from the demographic surveillance system of the Bandim Health Project in Bissau, Guinea-Bissau. The main outcome measures were adherence, completion rates and side effects during 9 months of IPT. The main outcome was 6 consecutive months of at least 80% adherence.

RESULTS

A total of 2631 children were identified as contacts of adult TB cases. Among the children identified, 1895 (72%) were evaluated for eligibility for IPT, and 820 were enrolled in the study: 609 were aged ≤ 5 years and 211 aged 5-15 years. A total of 79% of the prescribed doses were taken, with 65% of the children taking > 80% of their doses. In all, 51% completed more than 6 consecutive months of IPT.

CONCLUSION

Overall adherence to IPT was better than previously reported from TB-endemic areas, with 76% of the children completing at least 6 months of treatment, with more than 80% adherence.

Swimming behavior and prey retention of the polychaete larvae Polydora ciliata (Johnston)

The behavior of the ubiquitous estuarine planktotrophic spionid polychaete larvae Polydora ciliata was studied. We describe ontogenetic changes in morphology, swimming speed and feeding rates and have developed a simple swimming model using low Reynolds number hydrodynamics. In the model we assumed that the ciliary swimming apparatus is primarily composed of the prototroch and secondarily by the telotroch. The model predicted swimming speeds and feeding rates that corresponded well with the measured speeds and rates. Applying empirical data to the model, we were able to explain the profound decrease in specific feeding rates and the observed increase in the difference between upward and downward swimming speeds with larval size. We estimated a critical larval length above which the buoyancy-corrected weight of the larva exceeds the propulsion force generated by the ciliary swimming apparatus and thus forces the larva to the bottom. This modeled critical larval length corresponded to approximately 1 mm, at which, according to the literature, competence for metamorphosis and no more length increase is observed. These findings may have general implications for all planktivorous polychaete larvae that feed without trailing threads. We observed bell shaped particle retention spectra with a minimum prey size of approximately 4 μm equivalent spherical diameter, and we found that an ontogenetic increase in maximum prey size add to a reduction in intra-specific food competition in the various larval stages. In a grazing experiment using natural seawater, ciliates were cleared approximately 50% more efficiently than similar sized dinoflagellates. The prey sizes retainable for P. ciliata larvae covers the microplankton fraction and includes non-motile as well as motile prey items, which is why the larvae are trophically positioned among the copepods and dinoflagellates. Not only do larval morphology and behavior govern larval feeding, prey behavior also influences the feeding efficiency of Polydora ciliata.

Infusions of albumin increase free fraction of naproxen in healthy volunteers: a randomized crossover study

BACKGROUND

In vitro and in vivo studies have indicated that stabilizers present in pharmaceutical-grade albumin influence the albumin-binding capacity for highly protein-bound drugs. However, the half-life of the stabilizers and the quantitative effect have been difficult to determine.

METHOD

A randomized crossover study including six healthy volunteers was performed. The study subjects received 750 mg of oral naproxen 2 h before the study. They were randomized to receive either 100 ml of 20% albumin or 100 ml of Ringer's acetate solution intravenously. Frequent blood samples were obtained. The experiment was repeated 4 weeks later with the alternate solution. The serum samples were analysed to determine the concentrations of albumin, N-acetyl-DL-tryptophan, caprylate, and naproxen.

RESULTS

The free fraction of naproxen increased significantly after the infusion of albumin (P<0.05). The increase was concurrent with the appearance of N-acetyl-DL-tryptophan and caprylate in serum. The free fraction of naproxen declined rapidly after the albumin infusion was completed. N-acetyl-DL-tryptophan had a half-life of approximately 30 min. The half-life of caprylate was <15 min.

CONCLUSION

A transfusion of albumin results in an increase in the free fraction of naproxen. The transient increase in free-fraction naproxen decreased together with the detectable levels of the stabilizers N-acetyl-DL-tryptophan and caprylate. N-acetyl-DL-tryptophan and caprylate have a short half-life in serum.

SNPs in genes coding for ROS metabolism and signalling in association with docetaxel clearance

The dose of docetaxel is currently calculated based on body surface area and does not reflect the pharmacokinetic, metabolic potential or genetic background of the patients. The influence of genetic variation on the clearance of docetaxel was analysed in a two-stage analysis. In step one, 583 single-nucleotide polymorphisms (SNPs) in 203 genes were genotyped on samples from 24 patients with locally advanced non-small cell lung cancer. We found that many of the genes harbour several SNPs associated with clearance of docetaxel. Most notably these were four SNPs in EGF, three SNPs in PRDX4 and XPC, and two SNPs in GSTA4, TGFBR2, TNFAIP2, BCL2, DPYD and EGFR. The multiple SNPs per gene suggested the existence of common haplotypes associated with clearance. These were confirmed with detailed haplotype analysis. On the basis of analysis of variance (ANOVA), quantitative mutual information score (QMIS) and Kruskal-Wallis (KW) analysis SNPs significantly associated with clearance of docetaxel were confirmed for GSTA4, PRDX4, TGFBR2 and XPC and additional putative markers were found in CYP2C8, EPHX1, IGF2, IL1R2, MAPK7, NDUFB4, TGFBR3, TPMT (2 SNPs), (P<0.05 or borderline significant for all three methods, 14 SNPs in total). In step two, these 14 SNPs were genotyped in additional 9 samples and the results combined with the genotyping results from the first step. For 7 of the 14 SNPs, the results are still significant/borderline significant by all three methods: ANOVA, QMIS and KW analysis strengthening our hypothesis that they are associated with the clearance of docetaxel.

High agreement on family affluence between children's and parents' reports: international study of 11-year-old children

OBJECTIVE

To examine the agreement between parents' and children's reports on four items of family affluence: number of cars, own bedroom, number of family holidays and number of computers, and to analyse predictors of disagreement.

DESIGN

Cross-sectional child-parent validation study of selected items from an internationally standardised questionnaire.

SETTING

Survey conducted in schools in Denmark, Germany, Hungary, Italy, Poland and Scotland.

PARTICIPANTS

972 11-year-old children and their parents responded to the questionnaires.

RESULTS

The child item response rates were high (above 93%). The per cent agreement was low for holidays spent with family (52.5%), but high for the other three items of family affluence (76.2-88.1%). The kappa coefficients were good or excellent for all items (between 0.41 and 0.74) and the gamma coefficients were strong for all items (between 0.56 and 0.96). Children from single-parent families were more likely to over-report family affluence (OR 2.67; CI 1.83 to 3.89).

CONCLUSIONS

Young adolescents' self-reports of family affluence are fairly valid across the six countries. This finding suggests that the variables measured can be used in epidemiological studies that aim at ranking children according to socioeconomic position.

Infusion of albumin attenuates changes in serum protein binding of drugs in surgical patients compared with volume replacement with HAES

BACKGROUND

In vitro studies have indicated that stabilizers present in pharmaceutical-grade albumin influence albumin-binding capacity for highly protein bound drugs.

METHODS

A randomized study including 40 surgical patients, treated with either albumin or starch solutions, was performed. Volumes of colloids were given based on clinical indication. Blood samples were obtained. The serum samples were analyzed to determine the concentrations of albumin, tryptophan, N-acetyl-dl-tryptophan, caprylate and alpha-1-acid glycoprotein as well as in vitro drug binding of naproxen, warfarin and digitoxin.

RESULTS

During surgery, the albumin concentration declined in the Starch group from 26.8 to 15.3 g/l. It remained unchanged in the Albumin group (29.2 g/l). The two groups were analyzed with the pre-operative sample acting as the control. In the starch group, the percent free concentration of the drugs increased significantly (P<0.01): for naproxen from 0.2% to 0.6%, for warfarin from 1.2% to 1.8% and for digitoxin from 6.8% to 11.1%. In the Albumin group, the % free fraction of naproxen doubled from 0.1% to 0.2% (P<0.05), whereas the % free fraction of warfarin decreased from 1.1% to 1.0% (P<0.05). The free fraction of digitoxin remained unchanged.

CONCLUSIONS

Infusion of albumin during surgery resulted in maintained albumin values and almost maintained binding parameters for the study drugs, although some statistically significant changes were found. The use of starch solutions, however, led to in a reduction in albumin values and a significant reduction in binding parameters.

Bacterial profiling using skin grafting, standard culture and molecular bacteriological methods

OBJECTIVE

Wound healing can be delayed by the presence of colonising bacteria, and in polymicrobial wounds they may act synergistically to the further detriment of wound healing. In this pilot investigation, biopsy and swab samples were obtained as part of skin-graft operations performed on a chronic venous leg ulcer in order to study the spatial microbial diversity and to compare standard bacteriological and molecular biological techniques.

METHOD

The wound was sampled before excision, and sampling was undertaken at multiple locations across the wound. Swab samples and biopsies were subjected to culture analysis and 16S rRNA polymerase chain reaction (PCR), and to denaturing gradient gel electrophoresis (DGGE).

RESULTS

Within the wound samples, DGGE identified the major wound microflora components and established the extent of local differences in bacterial diversity.

CONCLUSION

This ongoing investigation has verified DGGE as a powerful tool for elucidating the clinical microbiology of a chronic disease state. It also suggests that skin graft operations are a novel way of obtaining multiple samples for in vivo bacteriology and for establishing the spatial distribution of bacteria in the complex micro-environment of chronic wounds.

Doxorubicin levels in the serum and ascites of patients with ovarian cancer

AIMS

To investigate the diffusion and accumulation of doxorubicin metabolites in the ascites of patients with ovarian cancer following intravenous injection, as a model for intraperitoneal accumulation of drugs.

METHODS

The concentrations of doxorubicin and its metabolites [Doxorubicinol (Dox-ol), 7-deoxydoxorubicinolone (7d-Dox-ol-on) and 7-deoxydoxorubicinone (7d-Dox-on)] were measured using high-performance liquid chromatography in the serum and in the ascites of seven patients with recurrent ovarian carcinoma suffering from symptomatic ascites and treated with intravenous doxorubicin.

RESULTS

Doxorubicin metabolites accumulated in the peritoneal cavity. The concentrations of the doxorubicin metabolites were initially higher in the serum compared to the ascitic fluid, but following several hours the doxorubicin metabolites became higher in the ascites, and remained detectable in the ascites for up to 168h, long after disappearance from the serum.

CONCLUSIONS

Doxorubicin metabolites accumulate in the ascites and are cleared more slowly from the peritoneal compartment than from the serum. Accumulation in the peritoneal cavity with prolonged half-life should be considered when administering medication in patients with ascites.

Studies of the separation and characterisation of mixtures of starch and cellulose derivatives by use of chromatography and mass spectrometry

In this work a method was developed for characterisation of commercially available polymers consisting of mixtures of substituted cellulose and starch. Selective hydrolysis with specific enzymes was used to achieve separation of the two polymers in the mixture. Enzymes hydrolysing (1-->4)-alpha-D and (1-->6)-alpha-D-glycosidic bonds were used for the starch part and enzymes hydrolysing (1-->4)-beta-D-glycosidic bonds for the cellulose part. The hydrolysed fraction was separated from the unhydrolysed fraction and characterised by use of size-exclusion chromatography (SEC), to confirm that enzyme hydrolysis of the different polymers had occurred. High-performance anion-exchange chromatography (HPAEC) was performed to determine the amount of unmodified glucose units (UGU) in the fractions. Electrospray ionisation mass spectrometry (ESIMS) was used for determination of the substituents. All products were converted to monomers by acid hydrolysis to simplify mass spectral identification of the substituents. The monomers were further subjected to acetylation with acetic acid anhydride to facilitate identification of the substituents. By combining the results from the different analytical techniques a picture of the samples was obtained.

Asthma and wheezing symptoms in young people in six Western countries

BACKGROUND

Asthma diagnosed in children shows wide geographical variations. Large scale surveys identify children with diagnosed asthma, but neglect the group of youngsters with multiple asthmatic complaints.

METHODS

A short validated asthma questionnaire was included in six national surveys of the Health Behaviour in School-Aged Children Study. Prevalence rates are presented by country, gender and age. Gender and age differences are analysed using binary and multinomial logistic regressions controlling for age and smoking.

RESULTS

Large country differences are observed in the prevalence rates of diagnosed asthma (8.6%-20.9% in boys, 6.9%-18.5% in girls) and young people with "asthma-like symptoms" (9.6%-20.2% in boys, 9.2%-23.1% in girls). When controlling for age and smoking, significant gender differences are observed (more diagnosed asthma in boys, more asthmatic symptoms in girls). Age differences were observed in adolescents with "asthma-like symptoms", but not in diagnosed asthma.

CONCLUSIONS

Using a short asthma questionnaire, large differences in diagnosed asthma and wheezing symptoms are observed between the countries. A considerable group of youngsters with "asthma-like symptoms" is detected in all countries, and may be an unrecognised risk group in health promotion.