Comparison of the biochemical composition of normal epidermal mucus and extruded slime of hagfish (Myxine glutinosa L.)

Hagfish (Myxine glutinosa) secrete normal epidermal mucus and extruded slime. The epidermal mucus is produced continuously to prevent pathogen adherence while the extruded slime is observed predominantly during feeding, provocation or stress. To date little is known about the involvement of extruded slime in the physiological functions of hagfish. In this preliminary study, innate immune enzymes and the protein composition of hagfish normal epidermal mucus and extruded slime were analysed and compared. The lysozyme specific activity of hagfish was observed approximately two-fold higher in extruded slime than that of epidermal mucus. The extruded slime had approximately 3.5-5.0 fold increased levels of alkaline phosphatase, cathepsin B and proteases in comparison to epidermal mucus. Protease characterization using specific inhibitors showed that the extruded slime had higher levels of serine trypsin-like proteases compared to metalloproteases whereas epidermal mucus showed equal proportion of both serine and metalloproteases. SDS-PAGE analysis showed high levels of three proteins with molecular masses in the range of 13-16kDa in the extruded slime. The LC/MS/MS analysis of protein bands 1, 2 and 3 showed closest matches to hemoglobulin-3, histone H3 and H2B proteins, respectively. The observation of elevated levels of innate immune parameters in the extruded slime suggested that the extruded slime has a significant role in innate immunity of hagfish against infectious pathogens.     

Self-Help for Depression via E-mail: A Randomised Controlled Trial of Effects on Depression and Self-Help Behaviour

Background

Self-help or self-management strategies are commonly used to deal with depression, but not all are thought to be helpful. A previous study found that sub-threshold depression symptoms were improved by an e-mail intervention that encouraged the use of evidence-based self-help strategies.

Aim

To investigate whether these e-mails were effective for adults with a range of depression symptomatology including major depression.

Method

The study was a parallel-group randomised controlled trial. Adult participants with any level of depressive symptoms were recruited over the internet from the United Kingdom, Australia, Canada, Ireland, New Zealand and the United States. Participants were randomised to receive a series of e-mails either promoting the use of evidence-based self-help strategies or containing depression information as a control. E-mails were sent automatically twice a week for six weeks. Depression symptoms were assessed with the self-rated Patient Health Questionnaire depression scale (PHQ-9).

Results

1736 participants with a wide range of symptom severity were recruited and assigned to active (n = 862) and control (n = 874) groups. However, there was a significant attrition rate, with 66.9% lost to follow-up at post-intervention. Both groups showed large improvements in depression symptoms overall, with no significant difference in improvement at the end of the study (mean difference in improvement 0.35 points, 95% CI: −0.57 to 1.28, d = 0.11, 95% CI: −0.06 to 0.27), although there was a small effect at the study mid-point. Results were similar for the sub-group of participants with major depression. The active group showed small to moderate improvements in self-help behaviour (d = 0.40, 95% CI: 0.23 to 0.56).

Conclusions

These results suggest that the e-mails were able to increase participants’ use of evidence-based self-help, but that this did not improve depression more than an attention control.

ClinicalTrials.gov

{"type":"clinical-trial","attrs":{"text":"NCT01399502","term_id":"NCT01399502"}}NCT01399502     

Evidence for limited spatial spread in an exotic longhorn beetle, Tetropium fuscum (Coleoptera: Cerambycidae)

The longhorn beetle Tetropium fuscum F. (Coleoptera: Cerambycidae) has become established in Nova Scotia, Canada, where it coexists with Tetropium cinnamopterum Kirby. The two Tetropium species share a similar ecological niche and use the same volatile cues for mate attraction. Exotic T. fuscum was introduced near Halifax, Nova Scotia, in approximately 1990, but the rate of its spread 20 yr later has not been documented. We report a large-scale, 3-yr study that investigates the distribution of T. fuscum relative to its site of introduction. Traps baited with male-produced pheromone and host volatiles were used to estimate the relative abundance of the two Tetropium species. Adult T. fuscum emerged 1-2 wk earlier than T. cinnamopterum each year between 2008 and 2010. The spatial distribution of T. fuscum was characterized by a sharp decline in abundance in relation to its point of introduction, up to a threshold distance of approximately 80 km beyond which T. fuscum is rare in comparison with native T. cinnamopterum. The restricted range of T. fuscum 20 yr after its introduction may be attributed to limited dispersal of adults or reproductive failures of low-density populations. The distribution of T. fuscum seemed stable between 2008 and 2010. In 1 of 3 yr, the abundance of T. cinnamopterum increased with the distance to the site of introduction of T. fuscum, which suggests competitive interactions between the two Tetropium species.     

Chronic oscillatory strain induces MLCK associated rapid recovery from acute stretch in airway smooth muscle cells

A deep inspiration (DI) temporarily relaxes agonist-constricted airways in normal subjects, but in asthma airways are refractory and may rapidly renarrow, possibly due to changes in the structure and function of airway smooth muscle (ASM). Chronic largely uniaxial cyclic strain of ASM cells in culture causes several structural and functional changes in ASM similar to that in asthma, including increases in contractility, MLCK content, shortening velocity, and shortening capacity. However, changes in recovery from acute stretch similar to a DI have not been measured. We have therefore measured the response and recovery to large stretches of cells modified by chronic stretching and investigated the role of MLCK. Chronic, 10% uniaxial cyclic stretch, with or without a strain gradient, was administered for up to 11 days to cultured cells grown on Silastic membranes. Single cells were then removed from the membrane and subjected to 1 Hz oscillatory stretches up to 10% of the in situ cell length. These oscillations reduced stiffness by 66% in all groups (P < 0.05). Chronically strained cells recovered stiffness three times more rapidly than unstrained cells, while the strain gradient had no effect. The stiffness recovery in unstrained cells was completely inhibited by the MLCK inhibitor ML-7, but recovery in strained cells exhibiting increased MLCK was slightly inhibited. These data suggest that chronic strain leads to enhanced recovery from acute stretch, which may be attributable to the strain-induced increases in MLCK. This may also explain in part the more rapid renarrowing of activated airways following DI in asthma.     

流感病毒的检测和分型技术研究进展

近年来,病毒性流感的不断流行和暴发已引起世界范围的广泛关注。为了更好地对流感病毒进行检测和分型,我们对目前流感病毒常用的血清学检测和分型方法、免疫荧光法、PCR方法、多重RT-PCR法、实时RT-PCR法、依赖核酸序列的扩增法、环介导等温扩增法、焦磷酸测序法、基因芯片技术分别进行了描述,并阐述了其优缺点。     

Internet-based CBT for depression with and without telephone tracking in a national helpline: randomised controlled trial

Background

Telephone helplines are frequently and repeatedly used by individuals with chronic mental health problems and web interventions may be an effective tool for reducing depression in this population.

Aim

To evaluate the effectiveness of a 6 week, web-based cognitive behaviour therapy (CBT) intervention with and without proactive weekly telephone tracking in the reduction of depression in callers to a helpline service.

Method

155 callers to a national helpline service with moderate to high psychological distress were recruited and randomised to receive either Internet CBT plus weekly telephone follow-up; Internet CBT only; weekly telephone follow-up only; or treatment as usual.

Results

Depression was lower in participants in the web intervention conditions both with and without telephone tracking compared to the treatment as usual condition both at post intervention and at 6 month follow-up. Telephone tracking provided by a lay telephone counsellor did not confer any additional advantage in terms of symptom reduction or adherence.

Conclusions

A web-based CBT program is effective both with and without telephone tracking for reducing depression in callers to a national helpline.

Trial Registration

Controlled-Trials.com ISRCTN93903959