Effect of timing and duration of a single chest compression pause on short-term survival following prolonged ventricular fibrillation

BackgroundPauses during chest compressions are thought to have a detrimental effect on resuscitation outcome. The Guidelines 2005 have recently eliminated the post-defibrillation pause. Previous animal studies have shown that multiple pauses of increasing duration decrease resuscitation success. We investigated the effect of varying the characteristics of a single pause near defibrillation on resuscitation outcome.MethodsPart A: 48 swine were anesthetized, fibrillated for 7 min and randomized. Chest compressions were initiated for 90 s followed by defibrillation and then resumption of chest compressions. Four groups were studied—G2000: 40 s pause beginning 20 s before, and ending 20 s after defibrillation, A1: a 20 s pause just before defibrillation, A2: a 20 s pause ending 30 s prior to defibrillation, and group A3: a 10 s pause ending 30 s prior to defibrillation. Part B: 12 swine (Group B) were studied with a protocol identical to Part A but with no pause in chest compressions. Primary endpoint was survival to 4 h.ResultsThe survival rate was significantly higher for groups A1, A2, A3, and B (5/12, 7/12, 5/12, and 5/12 survived) than for the G2000 group (0/12, p < 0.05). Survival did not differ significantly among groups A1, A2, A3, and B.ConclusionsThese results suggest that the Guidelines 2005 recommendation to omit the post-shock pulse check and immediately resume chest compressions may be an important resuscitation protocol change. However, these results also suggest that clinical maneuvers further altering a single pre-shock chest compression pause provide no additional benefit.     

Physiological and behavioural effects of imidacloprid on two ecologically relevant earthworm species (Lumbricus terrestris and Aporrectodea caliginosa)

Earthworms play key roles in soils and sub-lethal effects of environmental toxicants on these organisms should be taken seriously, since they might have detrimental effects on higher ecological levels. In laboratory experiments we have assessed sub-lethal effects (body mass change and cast production) of imidacloprid on two earthworm species commonly found in different agricultural soils (Lumbricus terrestris and Aporrectodea caliginosa). After 7 days of exposure in contaminated soil, a significant loss of body mass was found in both species exposed to imidacloprid concentrations as low as 0.66 mg kg^?1 dry soil. These losses ranged from 18.3 to 39% for A. caliginosa and from 7.4 to 32.4% for L. terrestris, respectively. Changes in cast production, a new biomarker previously validated using L. terrestris, was assessed by soil sieving using the recommended mesh size (5.6 mm) for L. terrestris and three different mesh sizes for A. caliginosa (5.6, 4 and 3.15 mm). The 4 mm mesh size proved to be the most suitable sieve size for A. caliginosa. Cast production increased by 26.2% in A. caliginosa and by 28.1% in L. terrestris at the lowest imidacloprid concentration tested (0.2 mg kg^?1 dry soil), but significantly decreased at higher concentrations (equal to and above 0.66 mg kg^?1 dry soil) in both earthworm species after the 7 days exposure experiment. These decreases in cast production ranged from 44.5 to 96.9% in A. caliginosa and from 42.4 to 95.7% in L. terrestris. The EC₅₀ for cast production were 0.84 (L. terrestris) and 0.76 mg kg^?1 dry soil (A. caliginosa), respectively. The detected sub-lethal effects were found close to the predicted environmental concentration (PEC) of imidacloprid, which is in the range of 0.33–0.66 mg kg^?1 dry soil. The biomarkers used in the present study, body mass change and changes in cast production, may be of ecological relevance and have shown high sensitivity for imidacloprid exposure of earthworms. The measurement of changes in cast production should be considered for inclusion in current standard tests.     

Influence of a soft drink with low pH on enamel surfaces: an in vitro study.

INTRODUCTION: The purpose of this study was to investigate, in vitro, the short-term effect of a soft drink (Coca Cola, Coca Cola Company, Atlanta, Ga) with low pH on enamel surfaces at different levels of intake. Effects on labial and palatal surfaces were also compared. METHODS: Thirty human enamel blocks (labial and palatal enamel surfaces) were randomly divided into 5 groups-1 control and 4 experimental. For 7 days, the enamel surfaces in the experimental groups were immersed in Coca-Cola at different frequencies: 1, 2, or 3 times per day for 20 minutes each, with each immersion followed by 1 hour in artificial saliva. Specimens in the fourth group were immersed for 1 minute in the soft drink followed by 3 minutes in artificial saliva, and the cycle repeated for 20 minutes to better simulate drinking habits. Control specimens remained in physiological serum at room temperature. The measurements were made at baseline (T0), day 3 (T1), and day 7 (T2) with a Knoop hardness tester. Analysis of the variance was used to find differences between the groups. For the multiple comparisons, the Dunnett test was used. The statistical level was accepted at P < .05. RESULTS: The experimental groups showed significant reductions in microhardness values. Differences between the test groups were not statistically significant, nor were differences between the labial and the palatal surfaces. CONCLUSIONS: Soft drink intake, even of relatively short duration, can reduce enamel microhardness. The frequency of intake seems not to play a decisive role on enamel microhardness. Care should be taken to avoid soft drinks during orthodontic treatment with fixed appliances.     

Conservative Management of Rectal Adenocarcinoma by Radiotherapy

Purpose: The aim of this study was to analyze the experience of Centre GF Leclerc for conservative and curative treatment by radiotherapy of low rectal cancer.

Patients and Methods: A total of 151 patients received radiotherapy alone for rectal adenocarcinoma with curative intent. They were clinically staged according to size (T1 < 3 cm, and T2 > 3 cm) and depth of infiltration (A = superficial, and B = impaired mobility and T3 fixed). Over the past 6 years, rectal ultrasound (US) has been used systematically, compared with computed tomographic scan and magnetic resonance imaging when needed. Intracavitary contact X ray was given to 129 patients (69%), and brachytherapy in 45 of 151. External radiotherapy was used in 34 cases (22.5%).

Results: Complete response was obtained in 93%. Local failures were observed in 50 cases (28%); two occurred in pelvic nodes after intracavitary X rays. Size (tumors > 3 cm) and alteration of mobility significantly influenced the rate of local failure (p = 0.009 and 0.007). The addition of external radiotherapy in patients with poor prognostic factors improved the local control rate. A total of 39 patients with recurrence were amenable to salvage surgery. After salvage treatment, the local control rate was 82% with unlimited follow-up. The 5-year actuarial survival rate was 57%, with a specific survival of 66%. There was no difference in local control or survival according to differentiation of the tumors and distance between anal margin and the inferior level of the lesion. Severe late effect (grade 3) was 3.8%. The sphincter preservation was obtained in 104 of 124 cases (84%). The sphincter function was judged to normal in 102 of 104 patients (98%).

Conclusion: Intracavitary contact X ray is the treatment of choice for clinical Stage T1A rectal tumors. External radiotherapy significantly improved the results of treatment of tumors > 3 cm. Clinical staging and transrectal ultrasound allows a safe selection of indications. Radiotherapy alone may be proposed for selected cases as an alternative to mutilating surgery for small rectal adenocarcinoma.     

Handedness and schizotypal features in healthy subjects.

BACKGROUND: An excess of mixed-handedness has been repeatedly reported in schizophrenia and schizotypy. Handedness is a measure of atypical cerebral lateralization, which is considered as a risk factor for schizophrenia. Several studies have attempted to identify correlations between handedness and dimensions of psychosis but the results obtained so far remain inconclusive. OBJECTIVE: To explore a possible link between mixed-handedness and the three classical dimensions of psychosis. As speech and language disorders may be associated with cerebral lateralization, we predicted a correlation between mixed-handedness and disorganized dimension. METHODS: We used the Schizotypal Personality Questionnaire (SPQ) and the Edinburgh Handedness Inventory (EHI) to study the correlation between mixed-handedness scores and positive, negative or disorganized dimensions in a sample of 62 healthy subjects. RESULTS: We found a negative correlation between mixed-handedness and the disorganized dimension of schizotypy, as individuals with prominent mixed-handedness showed more severe disorganization. CONCLUSION: We have identified a link between mixed-handedness and the disorganized dimension that may help to identify genetic vulnerability factors involved in psychosis.