•The AlaxoLito Plus Nasal Stent does not increase exercise performance or oxygen uptake.•RBC deformability changes depending on breathing mode and intensity.•Exhaled NO increases with stent ...applications compared to oral/nasal breathing.•Blood NO concentrations are not affected.
To investigate the influence of the intranasal AlaxoLito Plus Nasal Stent during exercise on nitric oxide (NO) synthesis, NO exhalation, red blood cell (RBC) deformability and oxygen uptake.
Parameters were measured before and after acute cycle ergometer test at different intensities. Spirometric, microrheological and NO parameters were determined for oral (OB), nasal (NB) and nasal-stent breathing (SB). RBC deformability was measured and elongation indices for 3.87 Pa and maximal deformability were calculated. RBC/plasma/exhaled NO, oxygen uptake and respiratory rate were determined.
Exhaled NO was higher at rest during OB compared to SB and NB and decreased after exercise with NB and SB. Plasma and RBC NO remained unaltered during intervention. RBC deformability increased at moderate intensity during SB. Deformability decreased at moderate and medium intensity with NB. Respiratory rate for same oxygen uptake did not differ between breathing settings.
The AlaxoLito Plus Nasal Stent may modulate deformability during moderate exercise and increase NO exhalation without major effects on oxygen uptake and performance.
While overall rates of meningococcal disease have been declining in the United States for the past several decades, New York City (NYC) has experienced two serogroup C meningococcal disease outbreaks ...in 2005-2006 and in 2010-2013. The outbreaks were centered within drug use and sexual networks, were difficult to control, and required vaccine campaigns.
Whole Genome Sequencing (WGS) was used to analyze preserved meningococcal isolates collected before and during the two outbreaks. We integrated and analyzed epidemiologic, geographic, and genomic data to better understand transmission networks among patients. Betweenness centrality was used as a metric to understand the most important geographic nodes in the transmission networks. Comparative genomics was used to identify genes associated with the outbreaks.
Neisseria meningitidis serogroup C (ST11/ET-37) was responsible for both outbreaks with each outbreak having distinct phylogenetic clusters. WGS did identify some misclassifications of isolates that were more distant from the outbreak strains, as well as those that should have been included based on high genomic similarity. Genomes for the second outbreak were more similar than the first and no polymorphism was found to either be unique or specific to either outbreak lineage. Betweenness centrality as applied to transmission networks based on phylogenetic analysis demonstrated that the outbreaks were transmitted within focal communities in NYC with few transmission events to other locations.
Neisseria meningitidis is an ever changing pathogen and comparative genomic analyses can help elucidate how it spreads geographically to facilitate targeted interventions to interrupt transmission.
Depending on the exercise variables and training design, resistance exercise can be applied to gain muscle mass, prevent diseases like osteoporosis and sarcopenia or generally increase strength ...capacity. But the influence on blood flow parameters and possible consequences in health and disease are less understood. To examine the possible impact of resistance exercise of different duration on hemorheology, oxidative stress and microvascular function, participants (n = 6) performed lower-limb resistance exercise of the quadriceps femoris. Loading consisted of 1 (S1), 5 (S5) and 10 (S10) sets, on separated days, at the individual 10 repetition maximum. Blood samples were taken before (Pre) and after (Post0) each set as well after a 25-min recovery period (Post25). Hemograms were measured to analyze hematocrit, white blood cell (WBC) count and red blood cell (RBC) count. RBC deformability and aggregation were measured by ektacytometry and syllectometry to determine hemorheological responses. Plasma and RBC nitrate were measured by chemiluminescence detection to determine nitric oxide production. Formation of N-tyrosine and plasma malondialdehyde to determine oxidative stress and lipid peroxidation were measured by immunostaining and ELISA, respectively.
Hematocrit, RBC, WBC count and aggregation increased Post0 in each protocol with subsequently decreased values Post25 below Pre values. High effect size was observed regarding deformability during the different sets. RBC nitrite analysis revealed effect size alterations between the trainings, whereas plasma nitrite was not affected. Effects size was evident in lipid peroxidation, whereas N-tyrosine concentration was not altered.
Lower-limb resistance exercise induced acute changes in hematological and hemorheological parameters, whereby intermittent hemodilution and plasma shifts seemed the major contributor. The acute adaptations of RBC function seen during short duration resistance exercise might contribute to beneficial effects on microvascular circulation with a low oxidative stress response.
•Resistance exercise influences the hematological profile•Acute alterations in hemorheology are observed immediately during exercise•Adaptations of blood rheology are seen after a recovery period•Impact on the microvascular system seems independent on exercise duration and intensity
Measurement of change in patients' health status is central to both clinical trials and clinical practice. Trials commonly use serial measurements by the patients at 2 points in time while clinicians ...use the patient's retrospective assessment of change made at 1 point in time. How well these measures correlate is not known.
To compare the 2 methods in measurement of changes in pain and disability.
Longitudinal survey of patients starting new therapy for chronic arthritis in 1994 and 1995. Surveys were completed at baseline (before intervention) and at 6 weeks and 4 months.
Community health education program and university medical and orthopedic services.
A total of 202 patients undertaking self-management education (n = 140), therapy with prednisone or methotrexate (n = 34), or arthroplasty of the knee or hip (n = 28).
Concordance between serial (visual analog scale for pain and Health Assessment Questionnaire for disability) and retrospective (7-point Likert scale) measures, sensitivities of these measures, and their correlation with patients' satisfaction with the change (7-point Likert scale).
When change was small (education group), serial measures correlated poorly with retrospective assessments (eg, r=0.13-0.21 at 6 weeks). With greater change, correlations improved (eg, r = 0.45-0.71 at 6 weeks). Average agreement between all pairs of assessments was 29%. Significant lack of concordance was confirmed in all 12 comparisons by McNemar tests (P = .02 to <.001) and by t tests (P = .03 to <.001). Retrospective measures were more sensitive to change than serial measures and correlated more strongly with patients' satisfaction with change.
The 2 methods for measuring health status change did not give concordant results. Including patient retrospective assessments in clinical trials might increase the comprehensiveness of information gained and its accord with clinical practice.
Objective To evaluate the role of iliac fixation in preventing migration of suprarenal and infrarenal aortic endografts. Methods Quantitative image analysis was performed in 92 patients with ...infrarenal aortic aneurysms (76 men and 16 women) treated with suprarenal (n = 36) or infrarenal (n = 56) aortic endografts from 2000 to 2004. The longitudinal centerline distance from the superior mesenteric artery to the top of the stent graft was measured on preoperative, postimplantation, and 1-year three-dimensional computed tomographic scans, with movement more than 5 mm considered to be significant. Aortic diameters were measured perpendicular to the centerline axis. Proximal and distal fixation lengths were defined as the lengths of stent-graft apposition to the aortic neck and the common iliac arteries, respectively. Results There were no significant differences in age, comorbidities, or preoperative aneurysm size (suprarenal, 6.0 cm; infrarenal, 5.7 cm) between the suprarenal and infrarenal groups. However, the suprarenal group had less favorable aortic necks with a shorter length (13 vs 25 mm; P < .0001), a larger diameter (27 vs 24 mm; P < .0001), and greater angulation (19° vs 11°; P = .007) compared with the infrarenal group. The proximal aortic fixation length was greater in the suprarenal than in the infrarenal group (22 vs 16 mm; P < .0001), with the top of the device closer to the superior mesenteric artery (8 vs 21 mm; P < .0001) as a result of the 15-mm uncovered suprarenal stent. There was no difference in iliac fixation length between the suprarenal and infrarenal groups (26 vs 25 mm; P = .8). Longitudinal centerline stent graft movement at 1 year was similar in the suprarenal and infrarenal groups (4.3 ± 4.4 mm vs 4.8 ± 4.3 mm; P = .6). Patients with longitudinal centerline movement of more than 5 mm at 1 year or clinical evidence of migration at any time during the follow-up period comprised the respective migrator groups. Suprarenal migrators had a shorter iliac fixation length (17 vs 29 mm; P = .006) and a similar aortic fixation length (23 vs 22 mm; P > .999) compared with suprarenal nonmigrators. Infrarenal migrators had a shorter iliac fixation length (18 vs 30 mm; P < .0001) and a similar aortic fixation length (14 vs 17 mm; P = .1) compared with infrarenal nonmigrators. Nonmigrators had closer device proximity to the hypogastric arteries in both the suprarenal (7 vs 17 mm; P = .009) and infrarenal (8 vs 24 mm; P < .0001) groups. No migration occurred in either group in patients with good iliac fixation. Multivariate logistic regression analysis revealed that iliac fixation, as evidenced by iliac fixation length ( P = .004) and the device to hypogastric artery distance ( P = .002), was a significant independent predictor of migration, whereas suprarenal or infrarenal treatment was not a significant predictor of migration. During a clinical follow-up period of 45 ± 22 months (range, 12-70 months), there have been no aneurysm ruptures, abdominal aortic aneurysm–related deaths, or surgical conversions in either group. Conclusions Distal iliac fixation is important in preventing migration of both suprarenal and infrarenal aortic endografts that have longitudinal columnar support. Secure iliac fixation minimizes the risk of migration despite suboptimal proximal aortic neck anatomy. Extension of both iliac limbs to cover the entire common iliac artery to the iliac bifurcation seems to prevent endograft migration.
The appropriate size threshold for endovascular repair of small abdominal aortic aneurysms (AAA) is unclear. We studied the outcome of endovascular aneurysm repair (EVAR) as a function of ...preoperative aneurysm diameter to determine the relationship between aneurysm size and long-term outcome of endovascular repair.
We reviewed the results of 923 patients treated in a prospective, multicenter clinical trial of EVAR. Small aneurysms were defined according to two size thresholds of 5.5 cm and 5.0 cm. Two-way analysis was used to compare patients with small aneurysms (<5.5 cm, n = 441) to patients with large aneurysms (≥5.5 cm, n = 482). An ordered three-way analysis was used to compare patients with small AAA (<5.0 cm, n = 145), medium AAA (5.0 to 5.9 cm, n = 461), and large AAA (≥6.0 cm, n = 317). The primary outcome measures of rupture, AAA-related death, surgical conversion, secondary intervention, and survival were compared using Kaplan-Meier estimates at 5 years.
Median aneurysm size was 5.5 cm. The two-way comparison showed that 5 years after EVAR, patients with small aneurysms (<5.5 cm) had a lower AAA-related death rate (1% vs 6%, P = .006), a higher survival rate (69% vs 57%, P = .0002), and a lower secondary intervention rate (25% vs 32%, P = .03) than patients with large aneurysms (≥5.5 cm). Three-way analysis revealed that patients with small AAAs (<5.0 cm) were younger (P < .0001) and were more likely to have a family history of aneurysm (P < .05), prior coronary intervention (P = .003), and peripheral occlusive disease (P = .008) than patients with larger AAAs. Patients with smaller AAAs also had more favorable aortic neck anatomy (P < .004). Patients with large AAAs were older (P < .0001), had higher operative risk (P = .01), and were more likely to have chronic obstructive pulmonary disease (P = .005), obesity (P = .03), and congestive heart failure (P = .004). At 5 years, patients with small AAAs had better outcomes, with 100% freedom from rupture vs 97% for medium AAAs and 93% for large AAAs (P = .02), 99% freedom from AAA-related death vs 97% for medium AAAs and 92% for large AAAs (P = .02) and 98% freedom from conversion vs 92% for medium AAAs and 89% for large AAAs (P = .01). Survival was significantly improved in small (69%) and medium AAAs (68%) compared to large AAAs (51%, P < .0001). Multivariate Cox proportional hazards modeling revealed that aneurysm size was a significant independent predictor of rupture (P = .04; hazard ratio HR, 2.195), AAA-related death (P = .03; HR, 2.007), surgical conversion (P = .007; HR, 1.827), and survival (P = .001; HR, 1.351). There were no significant differences in secondary intervention, endoleak, or migration rates between small, medium, and large AAAs.
Preoperative aneurysm size is an important determinant of long-term outcome following endovascular repair. Patients with small AAAs (<5.0 cm) are more favorable candidates for EVAR and have the best long-term outcomes, with 99% freedom from AAA death at 5 years. Patients with large AAAs (≥6.0 cm) have shorter life expectancy and have a higher risk of rupture, surgical conversion, and aneurysm-related death following EVAR compared to patients with smaller aneurysms. Nonetheless, 92% of patients with large AAAs are protected from AAA-related death at 5 years. Patients with AAAs of intermediate size (5 to 6 cm) represent most of the patients treated with EVAR and have a 97% freedom from AAA-related death at 5 years.
We reviewed the incidence of stent-graft migration after endovascular aneurysm repair in a prospective multicenter trial and identified factors that may predispose to such migration.
All patients who ...received treatment during the course of the multicenter AneuRx clinical trial were reviewed for evidence of stent-graft migration over 5 years, from 1996 to 2001. Post-deployment distance from the renal arteries to the proximal end of the stent graft and the proximal fixation length (length of the infrarenal neck covered by the stent graft) were determined in patients for whom pre-procedure and post-procedure computed tomography scans were measured in an independent core laboratory.
Stent-graft migration was reported in 94 of 1119 patients, with mean time after device implantation of 30 ± 11 months. Freedom from migration was 98.6% at 1 year, 93.4% at 2 years, and 81.2% at 3 years (Kaplan-Meier method). Subset (n = 387) analysis revealed that initial device deployment was lower in 47 patients with migration, as evidenced by a greater renal artery to stent-graft distance (1.1 ± 0.7 cm), compared with 340 patients without migration (0.8 ± 0.6 cm;
P = .006) on post-implantation computed tomography scan. Proximal fixation length was shorter in patients with migration (1.6 ± 1.4 cm) compared with patients without migration (2.3 ± 1.4 cm;
P = .005). There was significant variation in migration rate among clinical sites (
P < .001), ranging from 0% to 30% (median, 8%), with a greater than twofold difference in migration rate between the lowest quartile (6%) and the highest quartile (15%) clinical sites. Univariate and multivariate analysis revealed that renal artery to stent-graft distance (
P = .001) and proximal fixation length (
P = .005) were significant predictors of migration, and that each millimeter increase in distance below the renal arteries increased risk for subsequent migration by 5.8% and each millimeter increase in proximal fixation length decreased risk for migration by 2.5%. Pre-implantation aortic neck length, neck diameter, degree of device oversizing, correct versus incorrect oversizing, device type (stiff vs flexible), placement of proximal extender cuffs at the original procedure, and post-procedure endoleak were not significant predictors of migration. Migration was treated with placement of extender modules in 23 patients and surgical conversion in 7 patients; 64 patients (68%) with migration have required no treatment.
Stent-graft migration among patients treated in the AneuRx clinical trial appears to be largely related to low initial deployment of the device, below the renal arteries, and short proximal fixation length. Significant variation in migration rate among clinical sites highlights the importance of the technical aspects of stent-graft deployment. Advances in intraoperative imaging and deployment techniques that have been made since completion of the clinical trial facilitate precision of device placement below the renal arteries and should increase proximal fixation length. Whether this, together with increased iliac fixation length, will result in lower risk for migration remains to be determined in long-term follow-up studies.
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