Field walking tests are commonly employed to evaluate exercise capacity, assess prognosis and evaluate treatment response in chronic respiratory diseases. In recent years, there has been a wealth of ...new literature pertinent to the conduct of the 6-min walk test (6MWT), and a growing evidence base describing the incremental and endurance shuttle walk tests (ISWT and ESWT, respectively). The aim of this document is to describe the standard operating procedures for the 6MWT, ISWT and ESWT, which can be consistently employed by clinicians and researchers. The Technical Standard was developed by a multidisciplinary and international group of clinicians and researchers with expertise in the application of field walking tests. The procedures are underpinned by a concurrent systematic review of literature relevant to measurement properties and test conduct in adults with chronic respiratory disease. Current data confirm that the 6MWT, ISWT and ESWT are valid, reliable and responsive to change with some interventions. However, results are sensitive to small changes in methodology. It is important that two tests are conducted for the 6MWT and ISWT. This Technical Standard for field walking tests reflects current evidence regarding procedures that should be used to achieve robust results.
Many proteins exert their biological activities through small exposed surface regions called epitopes that are folded peptides of well‐defined three‐dimensional structures. Short synthetic peptide ...sequences corresponding to these bioactive protein surfaces do not form thermodynamically stable protein‐like structures in water. However, short peptides can be induced to fold into protein‐like bioactive conformations (strands, helices, turns) by cyclization, in conjunction with the use of other molecular constraints, that helps to fine‐tune three‐dimensional structure. Such constrained cyclic peptides can have protein‐like biological activities and potencies, enabling their uses as biological probes and leads to therapeutics, diagnostics and vaccines. This Review highlights examples of cyclic peptides that mimic three‐dimensional structures of strand, turn or helical segments of peptides and proteins, and identifies some additional restraints incorporated into natural product cyclic peptides and synthetic macrocyclic peptidomimetics that refine peptide structure and confer biological properties.
Short peptides can be constrained by cyclization to recreate key folded elements of protein structure, like β‐strands and β‐sheets, α‐helices, and turn motifs. Coupled with internal molecular constraints, cyclization has led to many protease‐resistant, potent and target‐selective, biologically active compounds for use in biology and medicine.
We tested the hypothesis that underrepresented students in active-learning classrooms experience narrower achievement gaps than underrepresented students in traditional lecturing classrooms, averaged ...across all science, technology, engineering, and mathematics (STEM) fields and courses. We conducted a comprehensive search for both published and unpublished studies that compared the performance of underrepresented students to their overrepresented classmates in active-learning and traditional-lecturing treatments. This search resulted in data on student examination scores from 15 studies (9,238 total students) and data on student failure rates from 26 studies (44,606 total students). Bayesian regression analyses showed that on average, active learning reduced achievement gaps in examination scores by 33% and narrowed gaps in passing rates by 45%. The reported proportion of time that students spend on in-class activities was important, as only classes that implemented high-intensity active learning narrowed achievement gaps. Sensitivity analyses showed that the conclusions are robust to sampling bias and other issues. To explain the extensive variation in efficacy observed among studies, we propose the heads-and-hearts hypothesis, which holds that meaningful reductions in achievement gaps only occur when course designs combine deliberate practice with inclusive teaching. Our results support calls to replace traditional lecturing with evidence-based, active-learning course designs across the STEM disciplines and suggest that innovations in instructional strategies can increase equity in higher education.
Summary Background Back pain remains a challenge for primary care internationally. One model that has not been tested is stratification of the management according to the patient's prognosis (low, ...medium, or high risk). We compared the clinical effectiveness and cost-effectiveness of stratified primary care (intervention) with non-stratified current best practice (control). Methods 1573 adults (aged ≥18 years) with back pain (with or without radiculopathy) consultations at ten general practices in England responded to invitations to attend an assessment clinic. Eligible participants were randomly assigned by use of computer-generated stratified blocks with a 2:1 ratio to intervention or control group. Primary outcome was the effect of treatment on the Roland Morris Disability Questionnaire (RMDQ) score at 12 months. In the economic evaluation, we focused on estimating incremental quality-adjusted life years (QALYs) and health-care costs related to back pain. Analysis was by intention to treat. This study is registered, number ISRCTN37113406. Findings 851 patients were assigned to the intervention (n=568) and control groups (n=283). Overall, adjusted mean changes in RMDQ scores were significantly higher in the intervention group than in the control group at 4 months (4·7 SD 5·9 vs 3·0 5·9, between-group difference 1·81 95% CI 1·06–2·57) and at 12 months (4·3 6·4 vs 3·3 6·2, 1·06 0·25–1·86), equating to effect sizes of 0·32 (0·19–0·45) and 0·19 (0·04–0·33), respectively. At 12 months, stratified care was associated with a mean increase in generic health benefit (0·039 additional QALYs) and cost savings (£240·01 vs £274·40) compared with the control group. Interpretation The results show that a stratified approach, by use of prognostic screening with matched pathways, will have important implications for the future management of back pain in primary care. Funding Arthritis Research UK.
•Rupture of three promising microalgae by high pressure homogenization was investigated.•Cell counting was the only reliable method for quantifying rupture of all the algae.•Tetraselmis suecica was ...highly susceptible to rupture by homogenization.•Chlorella sp. had similar resistance to rupture as the yeast Saccharomyces cerevisiae.•Nannochloropsis sp. was highly resistant to rupture.
The susceptibility to rupture of the microalgae Nannochloropsis sp., Chlorella sp. and Tetraselmis suecica by high pressure homogenization was compared quantitatively to the yeast Saccharomyces cerevisiae. Methods for quantifying cell rupture were investigated including cell counting, turbidity, metabolite release and particle sizing. Cell counting was the only reliable method for quantitative comparisons of all microalgae, with turbidity complicated by agglomeration of cell debris for T. suecica, and measurement of metabolite release affected by degradation occurring for all microalgae after significant rupture. The rupture of all microalgae followed exponential decay as a function of number of passes. The pressure required to achieve rupture of 50% of the cells per pass was determined to be 170, 1070, 1380, and ca. 2000bar for Tetraselmis sp., Chlorella sp., S. cerevisiae, and Nannochloropsis sp., respectively. These results extend the criteria for selecting microalgae for industrial applications beyond consideration of growth and compositional attributes.
We contacted 256 members of the Society for Pediatric Urology to determine their experience with patients who had undergone augmentation cystoplasty and who later became pregnant and delivered a ...baby. There were 15 pregnancies in 15 patients. Urinary tract infection or pyelonephritis complicated 9 of the 15 pregnancies (60%) and 4 patients experienced premature labor. Serum creatinine levels remained stable throughout pregnancy in 14 patients. Delivery was vaginal in 10 patients, each of whom had the native continence mechanism intact, and by cesarean section in 5, of whom 3 had had prior surgical reconstruction of the vesical neck. There were no intraoperative or postoperative complications. As a consequence of this study, we recommend that patients who have had an enterocystoplasty alone should not be at an increased risk for incontinence from a vaginal delivery. Conversely, patients who have undergone augmentation cystoplasty and either vesical neck reconstruction or placement of an artificial genitourinary sphincter to attain continence should undergo cesarean section delivery to avoid the potential for disruption of the continence mechanism.
Long-term indwelling catheters constitute a risk factor for the development of bladder malignancy. We assessed prospectively by bladder biopsy and urine cytology 25 consecutive spinal cord injury ...patients catheterized for a minimum of 10 years. Two cases of squamous cell carcinoma of the bladder were identified. Both patients with cancer had positive cytology findings and hematuria, suggesting that routine bladder biopsy in the asymptomatic patient may not be warranted. The high risk of malignancy (8 per cent) in these patients is yet another compelling reason to minimize the use of long-term indwelling catheters.
This study was conducted to quantitate and compare urinary solute transport by ileum and colon in an in vivo rat model. Rates of solute transport were compared by analysis of rate constants for each ...experiment. Sodium and bicarbonate are secreted while ammonium and chloride are absorbed by both ileum and colon. Potassium is absorbed by ileum and not transported by colon. There is a tendency for water movement into the bowel lumen with both intestinal segments. Quantitatively, the amount of bicarbonate secretion and the increase in intraluminal pH is greater with ileum than colon. There is a net osmolar absorption from ileum but not colon. Hydrogen ion or ammonium absorption accounts for the majority and bicarbonate secretion the minority of the acid load in both ileum and colon. Ammonium appears to be absorbed either along with chloride or in exchange for sodium.
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