Muscle sympathetic nerve activity at rest compared to exercise tolerance

Cardiovascular autonomic function is associated with physical performance and exercise training adaptation. The association between physical performance and sympathetic regulation is not well known. We hypothesized that sympathetic nervous system activity is associated with physical performance among male runners. The study population included 26 healthy male club runners [age 33 ± 5 years, body mass index (BMI) 24 ± 1 kg/m², VO_2max 58 ± 5 ml kg⁻¹ min⁻¹; mean ± SD]. Muscle sympathetic nerve activity (MSNA) was assessed from the peroneal nerve by the microneurography technique during 5 min of supine rest. Physical performance was assessed by time to exhaustion during treadmill running. The mean resting MSNA was 20 ± 6 bursts min⁻¹ (range 6–34). The mean time to exhaustion was 1,005 ± 136 s (range 720–1260). When the study group was divided into tertiles according to their running performance (866 ± 69, 994 ± 30 and 1154 ± 71 s in time to exhaustion, P < 0.0001 between the groups), MSNA was lower (P = 0.032) in the group with the best running performance (16 ± 5 bursts min⁻¹) compared to those with the worst running performance (23 ± 7 bursts min⁻¹). In conclusion, baseline sympathetic activity, measured by a microneurography at rest, may be associated with the maximal running performance of healthy subjects.     

Advanced interatrial block predicts ineffective cardioversion of atrial fibrillation: a FinCV2 cohort study

AimsRhythm control using electrical cardioversion (CV) is a common treatment strategy for patients with symptomatic atrial fibrillation (AF). To guide clinical decision making, we sought to assess if electrocardiographic interatrial blocks could predict CV failure or AF recurrence as the phenomenon is strongly associated with atrial arrhythmias.MethodsThis study included 715 patients who underwent a CV for persistent AF lasting >48 h. P-wave duration and morphology were analyzed in post-procedure or the most recent sinus rhythm electrocardiograms and compared with rates of CV failure and AF recurrence within 30 days after CV as well as their combination (ineffective CV).ResultsCV was unsuccessful in 63 out of 715 patients (8.8%) and AF recurred in 209 out of 652 (29.2%) patients within 30 days after CV. Overall, 272 (38.0%) CVs turned out ineffective. Advanced interatrial block (AIAB) defined as P-wave duration ≥120 ms and biphasic morphology in inferior leads (II, III and aVF) was diagnosed in 72 (10.1%) cases. AIAB was an independent predictor for CV failure (OR 4.51, 95%CI 1.76–11.56, p = .002), AF recurrence (OR 2.93, 95%CI 1.43–5.99, p = .003) and ineffective CV (OR 3.87, 95%CI 2.04–7.36, p < .001).ConclusionAIAB predicted CV failure, AF recurrence as well as their composite. This study presents an easy electrocardiographic tool for the identification of patients with persistent AF who might not benefit from an elective CV in the future.

KEY MESSAGES

• Interatrial blocks are very common in patients with atrial fibrillation.
• Advanced interatrial block predicts ineffective cardioversion.

     

Long-term results of arthroscopic Bankart repair: Minimum 10 years of follow-up

Purpose

This study investigated the long-term results of arthroscopic Bankart repair in terms of rates and timelines of recurrence of instability, with special interest in young adult patients aged ≤20 years.

Methods

Between 2000 and 2005, 186 shoulders [182 patients, 50 women, median age 26 (range 15–58) years] were operated on at a university hospital using arthroscopic Bankart repair because of instability after traumatic anteroinferior shoulder dislocation. Medical records were retrospectively reviewed and patients were assessed using postal questionnaires or telephone interview after a minimum of 10 years of follow-up [median 12.2 (range 10–16) years]. The primary outcome measure was recurrence of instability (assessed from 167 shoulders), other outcome measures included Oxford instability score (OIS), subjective shoulder value (SSV), and Western Ontario instability index (WOSI) (assessed from 157 shoulders).

Results

At the end of follow-up, 50/167 shoulders (30%) had recurrence of instability and 30/167 (18%) were subjected to reoperation due to instability symptoms. Twenty-six (52%) failures occurred within ≤2 years, 11 (22%) within 2–5 years, and 13 (26%) >5 years after surgery. Failure rate was 19/35 (54%) for patients aged ≤20 years and 31/132 (24%) for patients aged >20 years; reoperation rates were 11/35 (31%) and 19/132 (14%), respectively. Mean OIS was 20 (SD 9, range 12–50), SSV 83% (SD 21, range 10–100), and WOSI score 80 (SD 22, range 33–100).

Conclusions

Nearly one-third of patients had recurrence of instability after arthroscopic Bankart repair after a minimum of 10-year follow-up. Patients aged ≤20 years did poorly with more than half of the patients having recurrence; alternative stabilization techniques should probably be considered for these patients.

Level of evidence

IV.

     

5q11, 8p11, and 10q22 are recurrent chromosomal breakpoints in prostate cancer cell lines

Prostate cancer cell lines have been widely used as model systems characterizing pathogenetic, functional, and therapeutic aspects of prostate cancer development. However, their chromosomal compositions are poorly characterized. In this study, five prostate cancer cell lines-TSU-Pr1, JCA-1, NCI-H660, ALVA-31, and PPC-1-were investigated by G-banding, comparative genomic hybridization (CGH), and spectral karyotyping. The results were combined with our previous findings in the prostate cancer cell lines PC-3, DU145, and LNCaP. By comparative genomic hybridization (CGH), the most frequent losses were observed at 13q, 8p, 9p, and 4q, whereas gains were most commonly seen at 8q, 10q, and 18p. The composite karyotypes were characterized by multiple numerical and structural chromosomal aberrations. Recurrent breakpoints at 5q11, 8p11, and 10q22 were observed to participate in deletion and translocation events in five of the cell lines, suggesting the importance of tumor suppressor and/or oncogenes in these regions. ALVA-31 and PPC-1 shared nine identical derivative chromosomes, two of which have also been detected in PC-3. In addition, the identification of the same homozygous deletion at D10S541 and of an identical TP53 gene mutation in all three cell lines suggests a common origin of these cell lines.     

A new quantitative measure of disc degeneration

Background Context

The ability to adequately measure a phenomenon is critical to studying and understanding it. Since 1957, a variety of subjective visual grading methods have been used to assess disc degeneration, but these have been limited by gross ordinal scales and imprecision, as well as suboptimal reliability. Conceptually sound, objective, precise measurements are needed to advance knowledge of disc degeneration and its causes, progression, and consequences.

Effects of the wood extractives dehydroabietic acid and betulinol on reproductive physiology of zebrafish (Danio rerio)-a two-generation study

Two wood extractives, dehydroabietic acid (DHAA) and betulinol (BET), present in wood industry effluents were evaluated for their potential effects on the reproductive physiology of zebrafish. Adult zebrafish (F0) were exposed in a continuous flow-through system to 50 microg/l DHAA, 5 microg/l BET and 0.27 microg/l (1 nM) 17beta-estradiol (E2) for 3 months. Eggs were collected from F0 fish and the following F1 generation was exposed for 6 months. Biomarkers analyzed in both F0 and F1 fish were plasma vitellogenin (Vtg), testosterone (T), E2 (only females) and gonadal histology. DHAA and BET affected growth in terms of increased condition factor, and spawning was stimulated in BET-exposed fish of the F0 generation. F0 males exposed to DHAA and F0 females exposed to BET showed lower plasma Vtg concentration, but F1 males exposed to BET showed an increase in Vtg. In fish exposed to E2, the positive control for estrogenic effects, a pronounced increase in Vtg concentration was observed. Plasma sex steroids were not significantly affected by the wood extractives. However, although not statistically significant, the T concentration tended to be lower in fish of all BET treatments. The histological study revealed alterations in spermatogenic stages of F0 males exposed to DHAA and BET, which were different from those caused by E2. In F1 females, the percentage of vitellogenic oocytes was decreased in DHAA, BET and E2 exposures. This study shows that DHAA and BET may contribute to growth alterations and reproductive disturbances reported in fish exposed to pulp and paper mill effluents. Further, these wood extractives may have different effects in F0 and F1 generation fish, which highlights the value of two-generation studies in investigations regarding endocrine disrupting compounds.     

Early palmar plate fixation of distal radius fractures may benefit patients aged 50 years or older: a randomized trial comparing 2 different treatment protocols

Background and purpose — There is no consensus regarding optimal treatment of displaced distal radius fractures (DRFs). We compared the results of 2 treatment protocols: early palmar plating vs. primary nonoperative treatment of displaced DRFs.

Patients and methods — We performed a prospective randomized controlled study including 80 patients aged ≥ 50 years with dorsally displaced DRFs, excluding AO type C3 fractures. Patients were randomized to undergo either immediate surgery with palmar plating (n = 38), or initial nonoperative treatment (n = 42) after successful closed reduction in both groups. Delayed surgery was performed in nonoperatively treated patients showing early loss of alignment (n = 16). The primary outcome measure was Disabilities of the Arm, Shoulder, and Hand (DASH) score.

Results — Mean DASH scores at 24 months in the early surgery group were 7.9 vs. 14 in the initial nonoperative group (difference between means 6, 95% CI 0.1–11, p = 0.05). Delayed operation was performed on 16/42 of patients due to secondary displacement in the initial nonoperative group. In “as treated” analysis, DASH scores were 7 in the early surgery group, 13 in the nonoperative group, and 17 after delayed surgery (p = 0.02). The difference in DASH scores between early and delayed surgery was 9 points (CI 0.3–19, p = 0.02)

Interpretation — Treatment of DRFs with early palmar plating resulted in better 2-year functional outcomes for ≥50-year-old patients compared with a primary nonoperative treatment protocol. Delayed surgery in case of secondary displacement was not beneficial in terms of function.