Surface electromyographic analysis of exercises for the trapezius and serratus anterior muscles

STUDY DESIGN: This study used a prospective, single-group repeated-measures design to analyze differences between the electromyographic (EMG) amplitudes produced by exercises for the trapezius and serratus anterior muscles. OBJECTIVE: To identify high-intensity exercises that elicit the greatest level of EMG activity in the trapezius and serratus anterior muscles. BACKGROUND: The trapezius and serratus anterior muscles are considered to be the only upward rotators of the scapula and are important for normal shoulder function. Electromyographic studies have been performed for these muscles during active and low-intensity exercises, but they have not been analyzed during high intensity exercises. METHODS AND MEASURES: Surface electrodes recorded EMG activity of the upper, middle, and lower trapezius and serratus anterior muscles during 10 exercises in 30 healthy subjects. RESULTS: The unilateral shoulder shrug exercise was found to produce the greatest EMG activity in the upper trapezius. For the middle trapezius, the greatest EMG amplitudes were generated with 2 exercises: shoulder horizontal extension with external rotation and the overhead arm raise in line with the lower trapezius muscle in the prone position. The arm raise overhead exercise in the prone position produced the maximum EMG activity in the lower trapezius. The serratus anterior was activated maximally with exercises requiring a great amount of upward rotation of the scapula. The exercises were shoulder abduction in the plane of the scapula above 120 degrees and a diagonal exercise with a combination of shoulder flexion, horizontal flexion, and external rotation. CONCLUSION: This study identified exercises that maximally activate the trapezius and serratus anterior muscles. This information may be helpful for clinicians in developing exercise programs for these muscles.     

Risk factors for poor renal prognosis in children with hemolytic uremic syndrome

Many factors have been proposed as predictors of poor renal prognosis in children with hemolytic uremic syndrome (HUS), but their role is still controversial. Our aim was to detect the most reliable early predictors of poor renal prognosis to promptly identify children at major risk of bad outcome who could eventually benefit from early specific treatments, such as plasmapheresis. Prognostic factors identifiable at onset of HUS were evaluated by survival analysis and a proportional hazard model. These included age at onset, prodromal diarrhea (D), leukocyte count, central nervous system (CNS) involvement, and evidence of Shiga toxin-producing Escherichia coli (STEC) infection. Three hundred and eighty-seven HUS cases were reported; 276 were investigated for STEC infection and 189 (68%) proved positive. Age at onset, leukocyte count, and CNS involvement were not associated with the time to recovery. Absence of prodromal D and lack of evidence of STEC infection were independently associated with a poor renal prognosis; only 34% of patients D^–STEC^– recovered normal renal function compared with 65%–76% of D⁺STEC⁺, D⁺STEC^– and D^–STEC⁺ patients. In conclusion, absence of both D and evidence of STEC infection are needed to identify patients with HUS and worst prognosis, while D^– but STEC⁺ patients have a significantly better prognosis.     

Palliative treatment for malignant jaundice: endoscopic vs surgical approach

In this retrospective, comparative study a total of 107 patients, presenting with malignant inoperable strictures of common bile duct, due to a pancreatico-biliary malignancy, underwent palliative treatments. In a group, consisting of 82 patients (76.64%), endoscopic stenting procedures were performed; polyethylene stents or self-expanding metal stents were applied in 37 and 45 patients, respectively. The prerequisites for a successful endoscopic stenting were a) accuracy of diagnosis and b) exclusion of patients presenting with tumors potentially treatable by a curative resection. In the other group, consisting of 25 patients (23.36%), biliary-enteric bypass procedures were performed. Endoscopic treatment was successful in 97.5% of the cases (80/82); complication rate was 7.3% (6 patients on 82), and mortality rate was 3.6% (3 patients on 82). Median hospital stay was 13.4 and 7.3 days in patients treated with plastic stents and metallic stents, respectively. Bypass surgery was successful in 99% of the cases (24/25); complication rate was 24% (6 patients on 25), and mortality rate was 16% (4 patients on 25). Median hospital stay was 26 days. For the patients in whom a curative resection could not be performed, both the above mentioned methods resulted in a high rate of immediate technical and therapeutic success. However, the surgical approach showed a significantly higher rate in procedure-related mortality and morbidity; in addition, the hospital stay lasted longer in surgically treated patients. The patients who are definitely unsuitable for curative resection are better managed by positioning a stent. The use of metal stents should be preferred in those less serious patients who may supposedly survive longer.     

EPIC-Italy cohorts and multipurpose national surveys. A comparison of some socio-demographic and life-style characteristics

BACKGROUND: EPIC-Italy cohort study recruited subjects who voluntarily accepted to participate in the project. From the self-selected bases of the population sample, some bias could derive in the data interpretation when risk estimation for cancer disease related to life-style factors is the principal concern. Knowledge of the bias related to self-selected sampling is important for better directing the interpretation of the EPIC-Italy study results. METHODS: We investigated the characteristics of volunteer subjects recruited in the EPIC-Italy cohorts and compared them with those of the randomly selected subjects recruited in the Multipurpose ISTAT Surveys realized in the same period (1993-1998) in which the EPIC-cohorts were recruited. RESULTS: We found some differences, and in particular a different attitude towards cigarettes smoking and wine consumption, between the EPIC cohort and the Multipurpose ISTAT Surveys, as well as among geographical areas within the EPIC cohort. CONCLUSIONS: The uneven distribution of some characteristics suggests that the self-selected subjects were characterized by an overall lower consumption of wine and cigarette smoking even when the educational level was considered. This could suggest a generally more healthy life-style among subjects recruited on a volountary bases.     

Association between social class and food consumption in the Italian EPIC population

AIMS AND BACKGROUND: The objectives of the present study were to validate the social stratification variables adopted by the European Prospective Investigation into Cancer and Nutrition (EPIC) by comparing them with data from another independent source and to evaluate the geographic and social distribution of eating habits in the Italian EPIC population. METHODS: The validation of the socioeconomic data collected by the EPIC study was performed with the Turin Longitudinal Study as gold standard and using Cohen's kappa statistics to evaluate the concordance between the studies. We then analyzed food groups based on the consumption of meat and fats, carbohydrates, sweets and alcohol, and on an index of the Mediterranean diet. The standardized scores for each food group were subdivided into quartiles, which were used to compare persons in the extreme quartiles. Analysis of the differences in eating habits by center and by educational level was conducted separately for men and women, calculating the prevalence rate ratios and controlling for age, area of birth and body mass index. RESULTS: Concordance between the two data sources was high for educational level and low for the social-class index based on occupation. Most of the eating habits considered to be potentially harmful (high consumption of meat or fats and alcohol and low consumption of olive oil and fish) were more frequent in Northern than in Southern Italy. These habits were inversely correlated with educational level, especially in the South. CONCLUSIONS: A significant improvement in health could be obtained in the Italian population if culturally and socioeconomically disadvantaged individuals were to abandon their diet rich in meat and fats, as done by more advantaged persons. In the absence of preventive interventions specifically addressed to disadvantaged groups, it is likely that social inequalities in mortality and morbidity will increase.     

Increased proportion of CD8+ T-lymphocytes in the paratracheal lymph nodes of smokers with mild COPD

Previous studies have shown an increased number of inflammatory cells and, in particular, of CD8+ T lymphocytes, in central airways, peripheral airways, lung parenchyma and pulmonary arteries of smokers with COPD. In this study we investigated whether this inflammatory process is restricted to the lung tissue or whether a similar process is also present in the lymph nodes of these subjects. We examined paratracheal lymph nodes obtained from 6 smokers with COPD (FEV1/VC < 88% predicted and FEV1/FVC < 70% both before and after 200 microg of inhaled salbutamol) and 6 smokers without COPD (FEV1/VC > 88% predicted and FEV1/FVC > 70%) undergoing lung resection for localised pulmonary lesions. By immunohistochemistry we quantified CD4+ and CD8+ T-lymphocytes in the lymph nodes. Smokers with COPD had a decreased ratio CD4/CD8 compared to smokers without COPD. When all subjects were considered together, the ratio CD4/CD8 showed a positive correlation with the values of FEV1/VC and a negative correlation with cigarette consumption. In conclusion, smokers with COPD have an increased proportion of CD8+ cells in the lymph nodes, indicating that a T-lymphocyte pattern similar to that present in the lung tissue is also present in the lymph nodes of these subjects. This finding suggests that, in COPD, the polarisation of the immune response may occur in the regional lymph nodes, possibly as a consequence of the presentation of an endogenous antigen that remains unknown.