Effects of 2 ankle fatigue models on the duration of postural stability dysfunction

Context: Muscle fatigue is generally categorized in 2 ways: that caused by peripheral weakness (peripheral fatigue) and that caused by a progressive failure of voluntary neural drive (central fatigue). Numerous variables have been studied in conjunction with fatigue protocols, including postural stability, maximum voluntary contraction force, and reaction time. When torque recordings fall below 50% of a maximum voluntary contraction, the muscle is described as fatigued, but whether this value is a good indicator of fatigue has not been studied.Objective: To compare the effects of 2 ankle musculature fatigue protocols (30% and 50%) on the duration of postural stability dysfunction.Design: To assess differences between the 30% and 50% fatigue protocols, we calculated a 1 between-groups factor (subjects) and 2 within-groups factors (fatigue, test) analysis of variance.Setting: E.J. Nutter Athletic Training Facility.Patients or Other Participants: Twenty subjects (10 men, 10 women; age = 21.15 ± 2.23 years; height = 172.97 ± 9.86 cm; mass = 70.62 ± 14.60 kg) volunteered for this study. Subjects had no history of lower extremity injury, vestibular or balance disorders, functional ankle instability, or head injury in the past 6 months.Intervention(s): On separate days, subjects performed isokinetic fatiguing contractions of the plantar flexors and dorsiflexors in a 30% protocol (70% decrease in strength) and a 50% protocol (50% decrease in strength).Main Outcome Measure(s): Baseline and postfatigue postural stability scores were determined before and after the isokinetic fatiguing contractions. Plantar-flexion peak-torque measurements were obtained for the 2 fatiguing protocols. Three prefatigue and 12 postfatigue postural stability trials were recorded. Velocities for testing were 60°/s for plantar flexion and 120°/s for dorsiflexion.Results: Sway velocity was significantly greater when the ankle was fatigued to 30% (1.56°/s) than in the 50% condition (1.36°/s). For the 30% protocol, sway was significantly impaired when the pretest condition (1.19°/s) was compared with posttest trial 1 (2.34°/s), trial 2 (2.37°/s), and trial 3 (1.71°/s). For the 50% protocol, sway was significantly impaired when the pretest condition (1.27°/s) was compared with posttest trial 1 (2.02°/s).Conclusions: The 30% fatigue protocol resulted in significantly longer impairment of postural stability than the 50% protocol. Because the 30% protocol resulted in a greater effect but was relatively short-lived (approximately 75 to 90 s), it is more useful for research purposes.     

Dysferlin mutations in LGMD2B, Miyoshi myopathy, and atypical dysferlinopathies

DYSF encoding dysferlin is mutated in Miyoshi myopathy and Limb-Girdle Muscular Dystrophy type 2B, the two main phenotypes recognized in dysferlinopathies. Dysferlin deficiency in muscle is the most relevant feature for the diagnosis of dysferlinopathy and prompts the search for mutations in DYSF. DYSF, located on chromosome 2p13, contains 55 coding exons and spans 150 kb of genomic DNA. We performed a genomic analysis of the DYSF coding sequence in 34 unrelated patients from various ethnic origins. All patients showed an absence or drastic decrease of dysferlin expression in muscle. A primary screening of DYSF using SSCP or dHPLC of PCR products of each of 55 exons of the gene was followed by sequencing whenever a sequence variation was detected. All together, 54 sequence variations were identified in DYSF, 50 of which predicting either a truncated protein or one amino-acid substitution and most of them (34 out of 54) being novel. In 23 patients, we identified two pathogenic mutations, while only one was identified in 11 patients. These mutations were widely spread in the coding sequence of the gene without any mutational "hotspot."     

Erratum: Sodium channel gene (SCN5A) mutations in 44 index patients with brugada syndrome: Different incidences in familial and sporadic disease

In supplementation of previously published cardiac sodium channel (SCN5A) gene mutations that were cited in the text, in Table 2 and in Figure 2 we here apply an updated gene mutation nomenclature (Human Genome Variation Society, 2005) to facilitate mutation annotation comparison (SCN5A cDNA reference: NM_198056.1 or GI: 37622906; amino acid reference sequence: SWISS‐PROT entry Q14524, long splice variant, 2,016 amino acids): Mutation: c.2602delC Amino acid change: p.Glu868X Mutation: c.2581_2582delTT Amino acid change: p.Phe861Trp fsX90 Mutation: c.4477_4479delAAG Amino acid change: p.Lys1493del Mutation: c.5425C>A Amino acid change: p.Ser1812X     

Non‐invasive monitoring of muscle blood perfusion by photoplethysmography: evaluation of a new application

Aim: To evaluate a specially developed photoplethysmographic (PPG) technique, using green and near‐infrared light sources, for simultaneous non‐invasive monitoring of skin and muscle perfusion. Methods: Evaluation was based on assessments of changes in blood perfusion to various provocations, such as post‐exercise hyperaemia and hyperaemia following the application of liniment. The deep penetrating feature of PPG was investigated by measurement of optical radiation inside the muscle. Simultaneous measurements using ultrasound Doppler and the new PPG application were performed to elucidate differences between the two methods. Specific problems related to the influence of skin temperature on blood flow were highlightened, as well. Results: Following static and dynamic contractions an immediate increase in muscle perfusion was shown, without increase in skin perfusion. Liniment application to the skin induced a rapid increase in skin perfusion, but not in muscle. Both similarities and differences in blood flow measured by Ultrasound Doppler and PPG were demonstrated. The radiant power measured inside the muscle, by use of an optical fibre, showed that the near‐infrared light penetrates down to the vascular depth inside the muscle. Conclusions: The results of this study indicate the potentiality of the method for non‐invasive measurement of local muscle perfusion, although some considerations still have to be accounted for, such as influence of temperature on blood perfusion.     

Nurses' opportunistic interventions with patients in relation to smoking

AIM: This paper reports a study exploring nurses' provision of opportunistic health education on smoking for hospital patients. BACKGROUND: Smoking cessation guidelines recommend assessment of patients' smoking habits and provision of smoking cessation advice when possible, and highlight the importance of the role of nurses in health promotion and health education. In the past, nurses have been criticized for lack of knowledge, skills and confidence in relation to health education and the perception that it is additional to, rather than integrated with, nursing care. METHODS: A qualitative case study design was selected to explore the health education practice of 12 nurses working in acute wards in three general hospitals in Scotland. Data were collected in 2000 through non-participant observation, semi-structured interviews and the use of a radio-microphone to record nurse-patient interactions. The data analysis was guided by four key elements of health education practice: 'the teachable moment', 'readiness to learn', 'the provision of health information' and 'oral communication'. FINDINGS: Smoking was part of the nurses' agenda, as most recognized opportunities to introduce health education on smoking during nursing care, suggesting a tentative move towards the integration of health education with nursing care. Evidence from patients' interactions indicated ample opportunity for nurses to provide smoking-related health information. However, the content of nurses' interactions on smoking was variable, with some limited by poor communication skills and inadequate knowledge of smoking and smoking cessation. The context of the interactions was also important in understanding some of the restrictions on conversational progress. CONCLUSIONS: Nurses require the knowledge and skills to perform a health education role, and the inclusion of smoking cessation guidelines in nursing curricula would contribute to this. Where patients are in hospitals for short periods of time, opportunistic health education on smoking needs to be introduced as the basis for more specialist intervention.     

Ensuring NCLEX-RN success for first-time test-takers.

A major indicator of baccalaureate nursing program effectiveness is the pass rate on the National Council Licensure Examinations, Registered Nurse (NCLEX-RN) among first-time candidates. This article highlights the scope, instructional methods, and outcomes of the remediation program at Georgetown University School of Nursing & Health Studies (GU-NHS). With implementation of the multifaceted program, the NCLEX-RN pass rate for first-time takers at GU-NHS has been consistently above the national mean among all first-time candidates. Although it is impossible to determine which strategy made the greatest contribution to the success of the program, the cumulative effect is impressive and indicates the students are prepared for the challenge of the examination and contemporary nursing practice.     

Hypocomplementemic tubulointerstitial nephritis in IgG4-related disease

A novel lymphoproliferative disorder producing plasma cell expansion in the affected organ with fibrotic or sclerosing changes, known as 'IgG4-related disease', was defined in Japan by Umehara's group in 2010. We present the first case reported in Italy. In 2007, a 63-year-old man presented with epigastric pain and elevated serum lipase levels. Computed tomography of the abdomen revealed a Kuttner's tumor of the pancreas. The patient underwent a biliary-enteric anastomosis, and biopsy of the pancreas revealed massive infiltration of lymphocytes and plasma cells. The patient was diagnosed with chronic sclerosing pancreatitis. After one year, he began to show signs of sicca syndrome and at the same time developed progressive renal failure. Immunological tests revealed hypocomplementemia, and the renal biopsy specimen showed diffuse interstitial inflammation. The infiltrate was composed of lymphocytes, while infiltrating plasma cells showed immunoreactivity to IgG-4. Sialography using a radioisotope revealed severe involvement of the salivary glands, and Schirmer's test gave a positive result. This led us to diagnose hypocomplementemic tubulointerstitial nephritis in IgG4-related disease. Corticosteroid treatment resulted in rapid improvement including disappearance of the sicca syndrome and progressive amelioration of renal function. After six months, we discontinued steroid administration and started mycophenolate mofetil to maintain a low degree of immunosuppression. Follow-up after two years showed that this therapy continued to be quite effective in our patient.