PiggyBac-ing on a Primate Genome: Novel Elements, Recent Activity and Horizontal Transfer

To better understand the extent of Class II transposable element activity in mammals, we investigated the mouse lemur, Microcebus murinus, whole genome shotgun (2X) draft assembly. Analysis of this strepsirrhine primate extended previous research that targeted anthropoid primates and found no activity within the last 37 Myr. We tested the hypothesis that members of the piggyBac Class II superfamily have been inactive in the strepsirrhine lineage of primates during the same period. Evidence against this hypothesis was discovered in the form of three nonautonomous piggyBac elements with activity periods within the past 40 Myr and possibly into the very recent past. In addition, a novel family of piggyBac transposons was identified, suggesting introduction via horizontal transfer. A second autonomous element was also found with high similarity to an element recently described from the little brown bat, Myotis lucifugus, further implicating horizontal transfer in the evolution of this genome. These findings indicate a more complex history of transposon activity in mammals rather than a uniform shutdown of Class II transposition, which had been suggested by analyses of more common model organisms

The feasibility of measuring the activation of the trunk muscles in healthy older adults during trunk stability exercises

<p>Abstract</p> <p>Background</p> <p>As the older adult population increases, the potential functional and clinical burden of trunk muscle dysfunction may be significant. An evaluation of risk factors including the impact of the trunk muscles in terms of their temporal firing patterns, amplitudes of activation, and contribution to spinal stability is required. Therefore, the specific purpose of this study was to assess the feasibility of measuring the activation of trunk muscles in healthy older adults during specific leg exercises with trunk stabilization.</p> <p>Methods</p> <p>12 asymptomatic adults 65 to 75 years of age were included in the study. Participants performed a series of trunk stability exercises, while bilateral activation of abdominal and back extensor muscles was recorded by 24 pairs of Meditrace™ surface electrodes. Maximal voluntary isometric contractions (MVIC) were performed for electromyographic (EMG) normalization purposes. EMG waveforms were generated and amplitude measures as a percentage of MVIC were calculated along with ensemble average profiles. 3D kinematics data were also recorded, using an electromagnetic sensor placed at the left lateral iliac crest. Furthermore, a qualitative assessment was conducted to establish the participant's ability to complete all experimental tasks.</p> <p>Results</p> <p>Excellent quality abdominal muscle activation data were recorded during the tasks. Participants performed the trunk stability exercises with an unsteady, intermittent motion, but were able to keep pelvic motion to less than 10°. The EMG amplitudes showed that during these exercises, on average, the older adults recruited their abdominal muscles from 15–34% of MVIC and back extensors to less than 10% of MVIC. There were similarities among the abdominal muscle profiles. No participants reported pain during the testing session, although 3 (25%) of the participants reported delayed onset muscle soreness during follow up that was not functionally limiting.</p> <p>Conclusion</p> <p>Older adults were able to successfully complete the trunk stability protocol that was developed for younger adults with some minor modifications. The collected EMG amplitudes were higher than those reported in the literature for young healthy adults. The temporal waveforms for the abdominal muscles showed a degree of synchrony among muscles, except for the early activation from the internal oblique prior to lifting the leg off the table.</p

Reductions in co-contraction following neuromuscular re-education in people with knee osteoarthritis

Background Both increased knee muscle co-contraction and alterations in central pain processing have been suggested to play a role in knee osteoarthritis pain. However, current interventions do not target either of these mechanisms. The Alexander Technique provides neuromuscular re-education and may also influence anticipation of pain. This study therefore sought to investigate the potential clinical effectiveness of the AT intervention in the management of knee osteoarthritis and also to identify a possible mechanism of action. Methods A cohort of 21 participants with confirmed knee osteoarthritis were given 20 lessons of instruction in the Alexander Technique. In addition to clinical outcomes EMG data, quantifying knee muscle co-contraction and EEG data, characterising brain activity during anticipation of pain, were collected. All data were compared between baseline and post-intervention time points with a further 15-month clinical follow up. In addition, biomechanical data were collected from a healthy control group and compared with the data from the osteoarthritis subjects. Results: Following AT instruction the mean WOMAC pain score reduced by 56% from 9.6 to 4.2 (P<0.01) and this reduction was maintained at 15 month follow up. There was a clear decrease in medial co-contraction at the end of the intervention, towards the levels observed in the healthy control group, both during a pre-contact phase of gait (p<0.05) and during early stance (p<0.01). However, no changes in pain-anticipatory brain activity were observed. Interestingly, decreases in WOMAC pain were associated with reductions in medial co-contraction during the pre-contact phase of gait. Conclusions: This is the first study to investigate the potential effectiveness of an intervention aimed at increasing awareness of muscle behaviour in the clinical management of knee osteoarthritis. These data suggest a complex relationship between muscle contraction, joint loading and pain and support the idea that excessive muscle co-contraction may be a maladaptive response in this patient group. Furthermore, these data provide evidence that, if the activation of certain muscles can be reduced during gait, this may lead to positive long-term clinical outcomes. This finding challenges clinical management models of knee osteoarthritis which focus primarily on muscle strengthening

Older People, Sense of Coherence and Community

Population ageing is a global trend and even though years added to life often are lived in good health; it will have an impact on healthcare, housing and facilities, and social security costs. Healthy ageing in place, especially in one’s own home and community, increasingly receives attention from health professionals, researchers, and policymakers. In this chapter, we first discuss the meaning of the concept of healthy ageing, and how Sense of Coherence contributes to this process. Next, we discuss the characteristics of the community in which older people live their lives and how the community can provide resources (GRR and SRR) to strengthen Sense of Coherence and hence perceived well-being and quality of life

Community-based infant hearing screening in a developing country: parental uptake of follow-up services

<p>Abstract</p> <p>Background</p> <p>Universal newborn hearing screening is now considered an essential public health care for the early detection of disabling life-long childhood hearing impairment globally. However, like any health interventions in early childhood, parental support and participation is essential for achieving satisfactory uptake of services. This study set out to determine maternal/infant socio-demographic factors associated with follow-up compliance in community-based infant hearing screening programmes in a developing country.</p> <p>Methods</p> <p>After health educational/counselling sessions, infants attending routine childhood immunisation clinics at four primary care centres were enrolled into a two-stage infant hearing screening programme consisting of a first-stage screening with transient-evoked otoacoustic emissions and second-stage screening with automated auditory brainstem response. Infants referred after the second-stage screening were scheduled for diagnostic evaluation within three months. Maternal and infant factors associated with completion of the hearing screening protocol were determined with multivariable logistic regression analysis.</p> <p>Results</p> <p>No mother declined participation during the study period. A total of 285 out of 2,003 eligible infants were referred after the first-stage screening out of which 148 (51.9%) did not return for the second-stage, while 32 (39.0%) of the 82 infants scheduled for diagnostic evaluation defaulted. Mothers who delivered outside hospitals were significantly more likely to return for follow-up screening than those who delivered in hospitals (Odds ratio: 1.62; 95% confidence intervals: 0.98 – 2.70; p = 0.062). No other factors correlated with follow-up compliance for screening and diagnostic services.</p> <p>Conclusion</p> <p>Place of delivery was the only factor that correlated albeit marginally with infant hearing screening compliance in this population. The likely influence of issues such as the number of return visits for follow-up services, ineffective tracking system and the prevailing unfavourable cultural perception towards childhood deafness on non-compliance independently or through these factors warrant further investigation.</p

Mapping and phasing of structural variation in patient genomes using nanopore sequencing

Despite improvements in genomics technology, the detection of structural variants (SVs) from short-read sequencing still poses challenges, particularly for complex variation. Here we analyse the genomes of two patients with congenital abnormalities using the MinION nanopore sequencer and a novel computational pipeline—NanoSV. We demonstrate that nanopore long reads are superior to short reads with regard to detection of de novo chromothripsis rearrangements. The long reads also enable efficient phasing of genetic variations, which we leveraged to determine the parental origin of all de novo chromothripsis breakpoints and to resolve the structure of these complex rearrangements. Additionally, genome-wide surveillance of inherited SVs reveals novel variants, missed in short-read data sets, a large proportion of which are retrotransposon insertions. We provide a first exploration of patient genome sequencing with a nanopore sequencer and demonstrate the value of long-read sequencing in mapping and phasing of SVs for both clinical and research applications

Domain Altering SNPs in the Human Proteome and Their Impact on Signaling Pathways

Single nucleotide polymorphisms (SNPs) constitute an important mode of genetic variations observed in the human genome. A small fraction of SNPs, about four thousand out of the ten million, has been associated with genetic disorders and complex diseases. The present study focuses on SNPs that fall on protein domains, 3D structures that facilitate connectivity of proteins in cell signaling and metabolic pathways. We scanned the human proteome using the PROSITE web tool and identified proteins with SNP containing domains. We showed that SNPs that fall on protein domains are highly statistically enriched among SNPs linked to hereditary disorders and complex diseases. Proteins whose domains are dramatically altered by the presence of an SNP are even more likely to be present among proteins linked to hereditary disorders. Proteins with domain-altering SNPs comprise highly connected nodes in cellular pathways such as the focal adhesion, the axon guidance pathway and the autoimmune disease pathways. Statistical enrichment of domain/motif signatures in interacting protein pairs indicates extensive loss of connectivity of cell signaling pathways due to domain-altering SNPs, potentially leading to hereditary disorders

Stretching the spines of gymnasts: a review

Gymnastics is noted for involving highly specialized strength, power, agility and flexibility. Flexibility is perhaps the single greatest discriminator of gymnastics from other sports. The extreme ranges of motion achieved by gymnasts require long periods of training, often occupying more than a decade. Gymnasts also start training at an early age (particularly female gymnasts), and the effect of gymnastics training on these young athletes is poorly understood. One of the concerns of many gymnastics professionals is the training of the spine in hyperextension-the ubiquitous 'arch' seen in many gymnastics positions and movements. Training in spine hyperextension usually begins in early childhood through performance of a skill known as a back-bend. Does practising a back-bend and other hyperextension exercises harm young gymnasts? Current information on spine stretching among gymnasts indicates that, within reason, spine stretching does not appear to be an unusual threat to gymnasts' health. However, the paucity of information demands that further study be undertaken