Maximal strength training enhances strength and functional performance in chronic stroke survivors

Objective: This study aimed to demonstrate that maximal strength training improves muscle strength and to assess the effect of training on function, aerobic status, and quality-of-life among chronic stroke survivors. Design: Ten patients acted as their own controls for 4 wks, before an 8-week training intervention. Patients trained 3 days/wk, with four sets of four repetitions at 85%–95% one repetition maximum in unilateral leg press and plantarflexion with an emphasis on maximal mobilization of force in the concentric phase. Results: After training, leg press strength improved by 30.6 kg (75%) and 17.8 kg (86%); plantarflexion strength improved by 35.5 kg (89%) and 28.5 kg (223%) for the unaffected and affected limbs, respectively, significantly different from the control period (all P < 0.01). The 6-min walk test improved by 13.9 m (within training period; P = 0.01), and the Timed Up and Go test time improved by 0.6 secs (within training period; P < 0.05). There were no significant changes in walking economy, peak aerobic capacity, Four-Square Step Test, or health-related quality-of-life after training. Conclusions: Maximal strength training improved muscle strength in the most affected as well as in the nonaffected leg and improved Timed-Up-And-Go time and 6-min walk distance but did not alter Four-Step Square Test time, aerobic status, or quality-of-life among chronic stroke survivors

Neuromuscular performance of paretic versus non-paretic plantar flexors after stroke.

The objective of this study was to compare the neuromuscular function of the paretic and non-paretic plantar flexors (i.e. soleus, gastrocnemius medialis, lateralis) in chronic stroke patients. It was hypothesized that the contractile rate of force development (RFD) and neural activation, assessed by electromyogram (EMG) and V-waves normalized to the M-wave, and voluntary activation (twitch interpolation) would be reduced during plantar flexor maximum voluntary isometric contraction and that the evoked muscle twitch properties would be reduced in the paretic limb. Ten chronic stroke survivors completed the study. The main findings were that the paretic side showed deteriorated function compared to the non-paretic leg in terms of (1) RFD in all analyzed time windows from force onset to 250 ms, although relative RFD (i.e. normalized to maximum voluntary force) was similar; (2) fast neural activation (for most analyzed time windows), assessed by EMG activity in time windows from EMG onset to 250 ms; (3) V-wave responses (except for gastrocnemius medialis); (4) voluntary activation; (5) the evoked peak twitch force, although there was no evidence of intrinsic muscle slowing; (6) EMG activity obtained at maximal voluntary force. In conclusion, this study demonstrates considerable neuromuscular asymmetry of the plantar flexors in chronic stroke survivors. Effective rehabilitation regimes should be investigated

The Enzyme and the cDNA Sequence of a Thermolabile and Double-Strand Specific DNase from Northern Shrimps (Pandalus borealis)

Inge W. Nilsen et al...Background We have previously isolated a thermolabile nuclease specific for double-stranded DNA from industrial processing water of Northern shrimps (Pandalus borealis) and developed an application of the enzyme in removal of contaminating DNA in PCR-related technologies. Methodology/Principal Findings A 43 kDa nuclease with a high specific activity of hydrolysing linear as well as circular forms of DNA was purified from hepatopancreas of Northern shrimp (Pandalus borealis). The enzyme displayed a substrate preference that was shifted from exclusively double-stranded DNA in the presence of magnesium to also encompass significant activity against single-stranded DNA when calcium was added. No activity against RNA was detected. Although originating from a cold-environment animal, the shrimp DNase has only minor low-temperature activity. Still, the enzyme was irreversibly inactivated by moderate heating with a half-life of 1 min at 65°C. The purified protein was partly sequenced and derived oligonucleotides were used to prime amplification of the encoding cDNA. This cDNA sequence revealed an open reading frame encoding a 404 amino acid protein containing a signal peptide. By sequence similarity the enzyme is predicted to belong to a family of DNA/RNA non-specific nucleases even though this shrimp DNase lacks RNase activity and is highly double-strand specific in some respects. These features are in agreement with those previously established for endonucleases classified as similar to the Kamchatka crab duplex-specific nuclease (Par_DSN). Sequence comparisons and phylogenetic analyses confirmed that the Northern shrimp nuclease resembles the Par_DSN-like nucleases and displays a more distant relationship to the Serratia family of nucleases. Conclusions/Significance The shrimp nuclease contains enzyme activity that may be controlled by temperature or buffer compositions. The double-stranded DNA specificity, as well as the thermolabile feature, strengthens its potential for in vitro applications.This work was supported by the Research council of Norway, project number 138822/130, Nofima Marin and Biotec Marine Biochemicals. Since IWN and KØ are employees at Nofima Marin and LJH, ME, DRG and OL are employees at Marine Biochemicals the funders played a role in the design, data analysis and the decision to publish.Peer reviewe

High-intensity interval training vs. moderate-intensity continuous training in the prevention/management of cardiovascular disease

Moderate-intensity continuous training (MICT) has long been considered the most effective exercise treatment modality for the prevention and management of cardiovascular disease, but more recently high-intensity interval training (HIIT) has emerged into the clinical environment has been viewed as a potential alternative to MICT in accruing such benefits. HIIT was initially found to induce significant improvements in numerous physiological and health-related indices, to a similar if not superior extent to MICT. Since then, many studies have attempted to explore the potential clinical utility of HIIT, relative to MICT, with respect to treating numerous cardiovascular conditions such as coronary artery disease, heart failure, stroke, and hypertension. Despite this, however, the efficacy of HIIT compared to MICT with respect to in reversing the specific symptoms and risk factors of these cardiovascular pathologies for improved health and wellbeing as well as reduced morbidity and mortality is not well understood. In addition, HIIT is often perceived as very strenuous, which could potentially render it unsafe for those at risk of or afflicted with cardiovascular disease, but these issues are also yet to be reviewed. Furthermore, the optimal HIIT protocol for each of the cardiovascular disease cohorts has not been established. Thus, the purpose of this review article is to (i) evaluate the efficacy of HIIT relative to MICT in the prevention and management of cardiovascular conditions, and (ii) explore any potential safety issues surrounding the suitability and/or tolerability of HIIT for patients with cardiovascular disease, as well as the potential optimal prescriptive variables of HIIT for application in the clinical environment

Feeding behaviour and digestion physiology in larval fish – current knowledge and gaps and bottlenecks in research

Food uptake follows rules defined by feeding behaviour that determines the kind and quantity of food ingested by fish larvae as well as how live prey and food particles are detected, captured and ingested. Feeding success depends on the progressive development of anatomical characteristics and physiological functions and on the availability of suitable food items throughout larval development. The fish larval stages present eco-morpho-physiological features very different from adults and differ from one species to another. The organoleptic properties, dimensions, detectability, movements characteristics and buoyancy of food items are all crucial features that should be considered, but is often ignored, in feeding regimes. Ontogenetic changes in digestive function lead to limitations in the ability to process certain feedstuffs. There is still a lack of knowledge about the digestion and absorption of various nutrients and about the ontogeny of basic physiological mechanisms in fish larvae, including how they are affected by genetic, dietary and environmental factors. The neural and hormonal regulation of the digestive process and of appetite is critical for optimizing digestion. These processes are still poorly described in fish larvae and attempts to develop optimal feeding regimes are often still on a ‘trial and error’ basis. A holistic understanding of feeding ecology and digestive functions is important for designing diets for fish larvae and the adaptation of rearing conditions to meet requirements for the best presentation of prey and microdiets, and their optimal ingestion, digestion and absorption. More research that targets gaps in our knowledge should advance larval rearing

"På skalaen som er meg er det ikke plass til minuspoeng": En kvalitativ analyse av hvordan unge voksne med lett depresjon forstår seg selv og sin lidelse

Bakgrunn: Depresjon er en svært forekommende psykisk lidelse som kan ha ødeleggende konsekvenser for den som rammes. Det eksisterer likevel få kvalitative undersøkelser av hvordan depresjonen oppleves og forstås fra et førstehåndsperspektiv, selv om dette kan bidra med nyttig kunnskap om lidelsen. Til tross for denne mangelen blir det stadig fremhevet hvordan vi befinner oss i et individualisert samfunn som verdsetter uavhengighet og selvansvarlighet på bekostning av en anerkjennelse av den større kulturelle konteksten (Beck, 1989; Fox, Prilleltensky &amp; Austin, 2009; Furedi, 2004; Madsen, 2012). Depresjon bør dermed også forstås i lys av de kulturelle normene og idealene som preger samfunnet vårt. Ettersom unge voksne personer, definert ut fra begrepet ‘emerging adulthood’ (Arnett, 2000), befinner seg i livsfaser preget av endring og valgmuligheter, kan det være særlig interessant å undersøke hvordan disse forstår det å være deprimert. Formål: På bakgrunn av dette vil denne studien undersøke hvordan unge voksne med lett depresjon forstår seg selv og sin rolle i lidelsen. Dernest vil den utforske betydningen av å ha depresjon i dagens samfunn, belyst fra kritiske og samfunnspsykologiske teorier og annen relevant psykologisk forskning. Metode: Dette er et selvstendig forskningsprosjekt hvor materialet som har blitt innsamlet er basert på kvalitative semistrukturerte dybdeintervjuer. Disse ble utført med unge voksne personer (20 til 29 år) som går eller har gått til psykolog eller fastlege for lette depressive plager, eller som har en lett depresjonsdiagnose. Videre ble materialet analysert ved hjelp av en ‘Big Q’-tilnærming til tematisk analyse (Clarke, Brown &amp; Hayfield, 2015). Resultater: Det ble utformet fire hovedtemaer basert på analysen: (1) forståelsen av depresjonens årsak, (2) sammenhengen mellom depresjonen og selvforståelsen, (3) selvopplevd kontroll over depresjonen og depresjonens innvirkning på kontrollen, og (4) rollen av aksept i forståelsen av depresjonen. Fremtredende var hvordan de ulike informantenes forståelser av seg selv i lidelsen er nyanserte og varierende, men fremdeles viktige for deres opplevelser av å ha en depresjon. Konklusjon: De normene og idealene kritisk samfunnspsykologi hevder et individualisert samfunn preges av, som uavhengighet, ansvarlighet og selvrealisering, virker ikke til å samsvare med det å ha en depresjon. På noen måter opplever informantene i studien dermed at deres depresjon er uforenlig med forventninger de møter fra omverdenen. Måten depresjonen endrer deres atferd og fremtoning på, og hvordan den gjør det vanskelig å mestre ulike deler av livet, er uønsket og uforståelig både for dem selv og andre. Likevel antydet mange av informantene en aksept for hvordan depresjonen påvirker dem selv og livene deres, og et ønske om en tilsvarende aksept og forståelse fra andre mennesker

Effect of high aerobic intensity interval treadmill walking in people with chronic stroke: a pilot study with one year follow-up

Objective: To determine the physiological and functional responses from high aerobic intensity treadmill walking in 4 x 4-minute intervals in people with chronic stroke and to evaluate the feasibility of this mode of training. Method: This was a baseline control trial with 1 year follow-up in an outpatient rehabilitation setting at a university hospital. Eight people with chronic stroke participated in and completed the study. Their mean age was 48.9 (± 10.6) years. We tested uphill treadmill walking in 4 x 4-minute work periods at an intensity between 85% and 95% of peak heart rate from initial maximal treadmill testing. There were 3-minute active breaks between the intervals. The main outcome measures were peak oxygen uptake (VO2peak) and walking economy (Cw). Overall compliance and adverse events determine the feasibility. Results: VO2peak increased from 2.32 (± 0.44) to 2.60 (± 0.55) L • min–1 post training (P = .003). Walking economy (Cw) improved from 1.12 (± 0.15) to 1.04 (± 0.18) L • min–1 (P = .043). At 1 year follow-up, VO2peak was 2.59 (±0.58) L • min –1 and was not significantly different from posttraining measurement (P = 1.00). Cw was 1.19 (± 0.15) L • min–1 at 1 year follow-up and thus was worse than post training (P = .023). Functional improvements were found in the 6-minute walk test (6MWT) (P = .020), 10-meter walk test (10MWT) (P = .032), and Timed Up and Go test (TUG) (P = .002) at post tests. Conclusions: High aerobic intensity interval treadmill walking significantly increased VO2peak and improved Cw in these subjects. The training was feasible and may have important implications for cardiovascular health and future rehabilitation programs in this population