Epidemiologic Studies of Styrene and Cancer: A Review of the Literature

Epidemiologic Studies of Styrene and Cancer: A Review of the Literature: "Objective: To review the epidemiologic literature on styrene and cancer.
Methods: We reviewed studies of workers exposed to styrene in manufacturing and polymerization, in the reinforced plastics industry, and in styrene-butadiene rubber production. We also reviewed studies of workers monitored for styrene exposure, studies of environmental exposure, community-based case-control studies of lymphoma and leukemia, and studies of DNA adducts. Studies of workers in the reinforced plastics industry were considered more informative because of higher worker exposure and less confounding by other carcinogens.
Results: We found no consistent increased risk of any cancer among workers exposed to styrene. A study of reinforced plastic workers reported an association between average estimated styrene exposure and non-Hodgkin lymphoma (NHL, P = 0.05) but no trend with increasing duration of exposure. Other studies of styrene exposure and NHL found no increased risk. In two US studies of reinforced plastic workers, esophageal cancer mortality was increased, but these findings were generated in a background of multiple comparisons. Results for other cancers were unremarkable.
Conclusions: The available epidemiologic evidence does not support a causal relationship between styrene exposure and any type of human cancer.
(C)2009The American College of Occupational and Environmental Medicine"

Exposure Risk Assessment in an Aluminium Salvage Plant

Exposure Risk Assessment in an Aluminium Salvage Plant: "Introduction: A cross-sectional study was conducted to evaluate possible nervous or respiratory system effects from occupational aluminium exposure.
Methodology: Exposed workers in Al salvage plant were compared with controls. The investigation involved a standardized occupational and medical history and assessments of Al levels in ambiance, serum, and urine. This was combined with an evaluation of respiratory complaints, lung, and cognitive functions.
Results: Thirty workers exposed to Al were matched to 60 individuals without exposure to Al. Significantly higher internal doses of Al in urine were found in exposed workers (11.59 [mu]g/L), when compared with the controls (4.37 [mu]g/L). Few high Al atmospheric levels were obtained (0.12-10.86 mg/m3). No significant differences concerning respiratory or neurological symptoms prevalence between the two groups were reported.
Discussion: Chronic exposure to Al dust, at the levels documented in this study over the German limit values, does not induce measurable cognitive decline.
(C)2009The American College of Occupational and Environmental Medicine"

Monday sickness may say more about your job than your health

Monday sickness may say more about your job than your health: "More than a third of sick leave is taken on Mondays, and January is the most common month for absenteeism, research suggests."

The Association Between Beliefs About Low Back Pain and Work Presenteeism

The Association Between Beliefs About Low Back Pain and Work Presenteeism: "Objective: To examine the influence of beliefs about low back pain (LBP) on reduced productivity at work ('presenteeism') caused by LBP.
Methods: Two thousand five hundred seven individuals completed the Back Beliefs Questionnaire, the Fear Avoidance Beliefs questionnaire (FABQ), and questions about LBP-related work-absence, reduced work-productivity, pain, comorbidity, and demographics.
Results: Six hundred seventy (25%) individuals were of working age, employed and reported current LBP. Univariate models showed beliefs were more 'negative' in individuals with work-absence and reduced productivity (P = 0.0001). In multivariable analysis, controlling for confounders, 'FABQwork' was a unique predictor of both absenteeism and presenteeism (each, P = 0.0001), though with small effect sizes.
Conclusions: Negative beliefs about LBP are associated with both work absence and reduced work-productivity. Further investigations should examine their potential as a target for educational interventions when considering initiatives to reduce the socioeconomic costs of LBP.
(C)2009The American College of Occupational and Environmental Medicine"

A New Health Promotion Model for Lone Workers: Results of the Safety & Health Involvement For Truckers (SHIFT) Pilot Study

A New Health Promotion Model for Lone Workers: Results of the Safety & Health Involvement For Truckers (SHIFT) Pilot Study: "Objective: This study was designed to evaluate the effectiveness of a new health promotion model for lone workers.
Methods: A single group pre- or posttest design was used to evaluate intervention effectiveness for reducing body weight and increasing healthful and safe behaviors. Truck drivers (n = 29) from four companies participated in a 6-month intervention involving a weight loss and safe driving competition, computer-based training, and motivational interviewing.
Results: Objectively measured body weight reduced by 7.8 lbs ([DELTA]SD = 11.5, [DELTA]d = 0.68, P = 0.005), and survey measures showed significant reductions in dietary fat and sugar consumption. An objective measure of safe driving also showed significant improvement, and increases in exercise motivational stage and walking fitness approached significance.
Conclusions: Results suggest that the new intervention model is substantially more engaging and effective with truck drivers than previous education-based tactics.
(C)2009The American College of Occupational and Environmental Medicine

Of Interest due to the techniques used, specifically -

Weight Loss Competitions.
Team weight loss competitions reliably produce two or three times the amount of weight loss observed in the Holmes et al 22 study of truck drivers (as mentioned above), produce very low levels of attrition and are especially effective with male workers. Although the Holmes et al nutrition education intervention produced a mean weight loss of about 4 lbs, team weight loss competitions commonly produce average weight loss ranging from 10 to 18 lbs (see Refs. 24–26). The social and financial incentives in team competitions also produce low study attrition, which is a powerful consideration given high voluntary turnover in trucking and excessive attrition (58%) observed in a previous study of truck drivers.23 For example, attrition averaged only 2.6% (range, 0%–13%) across 10 different weight loss competitions reported Stunkard et al (study 2).26 Team competitions are also especially effective with male workers (see Ref. 25), and 95% of truck drivers are men.27 This enhanced effectiveness may be due in part to increased competitive and aggressive tendencies in men28 and/or to higher historical male participation rates in competitive team sports.29
Behavioral Computer-Based Training.
Behavioral computer-based training is twice as effective as passive training in booklets.30,31 Passive training formats in a previous intervention for truck drivers produced no significant improvements in health knowledge.23 A recent meta-analysis supports replacing passive educational booklets with more engaging training tactics. Burke et al 32reviewed the effectiveness of training tactics that were, by their classification, more or less engaging. Passive methods such as lectures, booklets, and videos were classified as less engaging; computer-based training or programmed instruction were classified as moderately engaging; and behavioral modeling and role playing were considered most engaging. In the studies reviewed, engaging methods were nearly three times more effective than less engaging methods. Although truck drivers cannot easily participate in the most engaging face-to-face training formats, moderately engaging computer-based training is a next-best alternative.
Behavioral Self-Monitoring (BSM).
BSM techniques, where individuals repeatedly observe, evaluate, and record aspects of their own behavior, are widely applied by physicians and psychologists to enhance motivation for change.33–35 BSM is increasingly applied in workplace interventions to enhance worker productivity and safety.33 Evidence suggests that BSM is particularly effective in combination with common intervention tactics such as goal setting, training, and feedback. For example, Olson and Winchester 33 reviewed 24 studies of workplace interventions that included self-monitoring and found that the standardized effect size for 66 intervention phases was large by Cohen's 36 standards (mean weighted d = 2.2; 95% CI = 1.7, 2.7; Cohen's standards are small d = 0.20, medium d = 0.50, and large d = .80), as was the mean effect size for interventions targeting driving and other safety behaviors (d = 1.8). Self-monitoring techniques can be easily administered at the individual level and are therefore well suited for involving isolated workers like truck drivers in health promotion programs.
MI.
MI has emerged as an alternative and more effective approach to health coaching than traditional office-based counseling, which lacks proven effectiveness for promoting exercise and healthy eating.37–39 Originally developed to reduce problem drinking and self-harming behaviors,40,41 MI is described as “a client-centered, directive method for enhancing intrinsic motivation to change by exploring and resolving client ambivalence.”42 MI techniques have been operationally defined,43 and examples of techniques include reflective listening, asking open-ended questions, and encouraging change talk. The guiding principles are to express empathy, develop discrepancy, avoid argumentation, roll with resistance, and support self-efficacy.41,42 Burke et al 44 conducted a meta-analysis of 31 controlled clinical trials of MI treatments. Standardized differences between treatment and control group means ranged from d = 0.25 to d = 0.56, with effects on exercise and diet averaging d = 0.53 (95% CI = 0.32, 0.74). MI is a good fit for truck drivers because it can be delivered anywhere a worker can receive cell phone service.

"

Spinal fusion surgery over-servicing

Spinal fusion surgery over-servicing: "http://www3.interscience.wiley.com/journal/122678682/abstract?CRETRY=1&SRETRY=0

A disproportionate increase in spinal fusion surgery in private practice in recent years may reflect overservicing by surgeons, Australian researchers say"

N-95 Respirators and Surgical Masks

N-95 Respirators and Surgical Masks: "http://www.cdc.gov/niosh/blog/nsb101409_respirator.html October 10, 2009, by Lisa Brosseau, Ph.D., and Roland Berry Ann. The emergence of H1N1 has created considerable interest about the use of surgical masks and respirators as infection control measures. Given the recent issuance of revised CDC infection control guidance for healthcare personnel that include recommendations for use of N-95 respirators, NIOSH has posted a new blog that examines the scientific principles behind the design and performance of these devices. Read more and comment on the NIOSH Science Blog."

Safety and Health for Tattooists and Piercers

Safety and Health for Tattooists and Piercers: "http://www.cdc.gov/niosh/topics/bbp/bodyart/"

Novel H1N1 Influenza and Respiratory Protection for Health Care Workers

Novel H1N1 Influenza and Respiratory Protection for Health Care Workers: "

Your hospital has been seeing a large number of patients with influenza-like symptoms, many of whom turn out to be infected with the novel H1N1 influenza A virus. You have ...

Also:

http://www.cdc.gov/h1n1flu/guidelines_infection_control.htm"

Mandatory Vaccination of Health Care Workers

http://content.nejm.org/cgi/content/short/NEJMp0910151v1?rss=1&query=current

Lesions missed without whole body exams

Lesions missed without whole body exams: "The importance of performing a whole body skin examination on patients presenting with skin lesion has been underlined by a new study showing that most patients have additional asymptomatic lesions that would otherwise be missed."

Spinal X-ray curbs

Spinal X-ray curbs: "Health minister Nicola Roxon says health budget savings will be made by creating three new 'therapeutic groups' under the PBS and by encouraging doctors to request region-specific spinal X-rays for particular clinical indications."

Tackle work stress, bosses told

Tackle work stress, bosses told: "Employers need to pay more attention to the levels of stress and anxiety in the workplace, key NHS advisers say."

Obese 'struggle to earn living'

Obese 'struggle to earn living': "Obese people in the UK are struggling to earn above the national average income, according to a survey.

Just under half (46%) earn more than £20,000 a year, which is the national average, while the majority earn between £10,000 and £15,000.

The survey conducted by YouGov also indicates that only 5% of people feel their weight has held them back..............."

EPA: Highlights of the Child-Specific Exposure Factors Handbook

EPA: Highlights of the Child-Specific Exposure Factors Handbook
http://www.epa.gov/childexpfactors/highlights

NIOSH Respirator Trusted-Source Information Page

The Respirator Trusted-Source Information Page may be viewed at:

www.cdc.gov/niosh/npptl/topics/respirators/disp_part/RespSource.html

CDC Vision Health Initiative Website

Announcement: Vision Health Initiative Website

CDC has created a new Vision Health Initiative website with information regarding vision and eye health, projects with diverse
stakeholders, journal publications and reports, and vision health--related resources for professionals and consumers. The website
includes an interactive map displaying state-specific vision and eye health statistics. With this tool, states that use the Behavioral Risk Factor Surveillance System visual impairment and access to eye care module can produce reports and presentations with data specific to their states. The website can be accessed at http://www.cdc.gov/visionhealth.

In 2004, approximately 3.3 million persons aged ?40 years had blindness or visual impairment; this number is predicted to double by 2030 because of increases in diabetes and other chronic diseases and aging of the U.S. population (1). With early detection and treatment, half of all blindness can be prevented or reversed (2).

References

1. Prevent Blindness America. Vision problems in the U.S. 2008 update to the fourth edition. Available at
http://www.preventblindness.org/vpus. Accessed October 29, 2009.

2. Sommer A, Tielsch JM, Katz J, et al. Racial differences in the cause-specific prevalence of blindness in east Baltimore. N Engl J Med 1991;325:1412--7

Surgical Mask vs N95 Respirator for Preventing Influenza Among Health Care Workers: A Randomized Trial [Original Contribution]

Surgical Mask vs N95 Respirator for Preventing Influenza Among Health Care Workers: A Randomized Trial [Original Contribution]: "

Context Data about the effectiveness of the surgical mask compared with the N95 respirator for protecting health care workers against influenza are sparse. Given the likelihood that N95 respirators will be in short supply during a pandemic and not available in many countries, knowing the effectiveness of the surgical mask is of public health importance.

Objective To compare the surgical mask with the N95 respirator in protecting health care workers against influenza.

Design, Setting, and Participants Noninferiority randomized controlled trial of 446 nurses in emergency departments, medical units, and pediatric units in 8 tertiary care Ontario hospitals.

Intervention Assignment to either a fit-tested N95 respirator or a surgical mask when providing care to patients with febrile respiratory illness during the 2008-2009 influenza season.

Main Outcome Measures The primary outcome was laboratory-confirmed influenza measured by polymerase chain reaction or a 4-fold rise in hemagglutinin titers. Effectiveness of the surgical mask was assessed as noninferiority of the surgical mask compared with the N95 respirator. The criterion for noninferiority was met if the lower limit of the 95% confidence interval (CI) for the reduction in incidence (N95 respirator minus surgical group) was greater than –9%.

Results Between September 23, 2008, and December 8, 2008, 478 nurses were assessed for eligibility and 446 nurses were enrolled and randomly assigned the intervention; 225 were allocated to receive surgical masks and 221 to N95 respirators. Influenza infection occurred in 50 nurses (23.6%) in the surgical mask group and in 48 (22.9%) in the N95 respirator group (absolute risk difference, –0.73%; 95% CI, –8.8% to 7.3%; P = .86), the lower confidence limit being inside the noninferiority limit of –9%.

Conclusion Among nurses in Ontario tertiary care hospitals, use of a surgical mask compared with an N95 respirator resulted in noninferior rates of laboratory-confirmed influenza.

Trial Registration clinicaltrials.gov Identifier: NCT00756574

Published online October 1, 2009 (doi:10.1001/jama.2009.1466).

"

Self-paced exercise is less physically challenging than enforced constant pace exercise of the same intensity: influence of complex central metabolic

Self-paced exercise is less physically challenging than enforced constant pace exercise of the same intensity: influence of complex central metabolic control:

"Objective: To examine whether self-pacing reduces the physiological challenge of performing 5000 m rowing ergometry exercise in comparison with a matched-intensity exercise condition in which a constant effort pacing strategy is enforced.

Methods: Nine healthy well-trained male participants volunteered to participate in three 5000 m rowing conditions (two submaximal and one maximal conditions) in an individualised order. In the submaximal conditions, participants were required to (1) perform 5000 m at a constant rating of perceived exertion (RPE 15-Hard) (SubRPE) or (2) perform 5000 m at an enforced constant pace equivalent to the mean power output (PO) of the SubRPE condition (SubEXT). A maximal condition (MaxTT) was included to disguise the purpose of the study and to facilitate an element of randomisation in the test sequence. Dynamic intratest responses were assessed every 30s: PO, Vo₂, iEMG, core (T_c) and skin temperatures (T_sk).

Results: There was no difference between performance times of the two submaximal trials. The mean PO represented 83.83 (SD 8.88)% (SubRPE) and 83.40 (8.84)% (SubEXT) of the mean MaxTT power output. T_c (SubRPE:38.46 (0.23)°C, SubEXT:38.72 (0.36)°C; p<0.01), post-test BLa (SubRPE:5.24 (2.18), SubEXT:6.19 (2.51) mmol/l; p<0.05) and iEMG (p<0.05) were significantly elevated in SubEXT compared with SubRPE. There were no differences in the dynamics of HR or Vo₂ between SubEXT and SubRPE. The intratest stroke-to-stroke variability of power output was significantly greater in the SubRPE condition compared with SubEXT (p<0.01).

Conclusions: Enforced constant paced exercise presents a significantly greater physiological challenge than self-paced exercise. The ability to dynamically self-pace effort via manipulations of power output during exercise is an important behavioural response to homeostatic challenges and thus forms an integral part of a complex central regulatory process.
"

Effect of taping on the shoulders of Australian football players

Effect of taping on the shoulders of Australian football players:

"Background: Taping of the shoulder is common in many sports, particularly Australian football, a contact sport that often involves marking (catching) the ball overhead and has a high incidence of shoulder instability.

Hypothesis: Taping of the shoulder reduces glenohumeral joint laxity and improves proprioception without impairing function.

Study design: Crossover study design.

Methods: 33 male players aged 18–31 years were recruited from a local Australian football club. The dominant shoulder of each player was tested with and without taping in a randomised fashion by an examiner blinded to the presence or absence of taping. The tests were (1) inferior glenohumeral joint laxity (the Orthopaedic Research Institute laxometer), (2) shoulder joint position sense accuracy using an optical tracking system, and (3) handballing accuracy.

Results: The methods for testing laxity and joint position sense had good intraobserver reliability and sensitivity. All subjects tolerated the taping and testing. Glenohumeral joint laxity (p = 0.75), joint position sense (p = 0.56) and handballing accuracy (p = 0.6) were not changed by taping.

Conclusions: Taping of the shoulder joint in uninjured and non-symptomatic Australian football players in a pattern that attempted not to restrict their range of overhead movement did not significantly affect the accuracy of joint position sense, inferior laxity or handball accuracy.

Clinical relevance: These data suggest that taping of the shoulder is unlikely to decrease the incidence of injury—specifically dislocation—of the shoulder in Australian football players.
"

Would you dope? A general population test of the Goldman dilemma

Would you dope? A general population test of the Goldman dilemma:

"Objective: To test Goldman's dilemma on a general population sample by asking whether they would take the Faustian bargain of a drug that guaranteed sporting success but would result in their death in 5 years' time. Between 1982 and 1995 a bi-annual survey using this dilemma suggested half of all elite athletes would take the drug.

Design: A random telephone survey of 250 members of the Australian general public, with counterbalanced presentation of success and death.

Main outcome measures: Respondents gave age, gender, sports engagement and response to the dilemma (yes/no).

Results: Only two of a sample of 250 reported they would take the bargain offered by the dilemma.

Conclusions: Athletes differ markedly from the general population in response to the dilemma. This raises significant practical and ethical dilemmas for athlete support personnel. The psychometry of the dilemma needs to be established more comprehensively for general and athlete populations.
"

Non-steroidal anti-inflammatory drugs in sports medicine: guidelines for practical but sensible use

Non-steroidal anti-inflammatory drugs in sports medicine: guidelines for practical but sensible use: "Introduction:

Non-steroidal anti-inflammatory drugs (NSAID) are commonly used in sports medicine. NSAID have known anti-inflammatory, analgesic, antipyretic and antithrombotic effects, although their in-vivo effects in treating musculoskeletal injuries in humans remain largely unknown. NSAID analgesic action is not significantly greater than paracetamol for musculoskeletal injury but they have a higher risk profile, with side-effects including asthma exacerbation, gastrointestinal and renal side-effects, hypertension and other cardiovascular diseases.

Discussion:

The authors recommend an approach to NSAID use in sports medicine whereby simple analgesia is preferentially used when analgesia is the primary desired outcome. However, based both on the current pathophysiological understanding of most injury presentations and the frequency that inflammation may actually be a component of the injury complex, it is premature to suppose that NSAID are not useful to the physician managing sports injuries. The prescribing of NSAID should be cautious and both situation and pathology specific. Both dose and duration minimisation should be prioritised and combined with simple principles of protection, rest, ice, compression, elevation (PRICE), which should allow NSAID-sparing. NSAID use should always be coupled with appropriate physical rehabilitation.

Conclusion:

NSAID are probably most useful for treating nerve and soft-tissue impingements, inflammatory arthropathies and tenosynovitis. They are not generally indicated for isolated chronic tendinopathy, or for fractures. The use of NSAID in treating muscle injury is controversial. Conditions in which NSAID use requires more careful assessment include ligament injury, joint injury, osteoarthritis, haematoma and postoperatively.

"

Does occupational success influence longevity among England test cricketers?

Does occupational success influence longevity among England test cricketers?:

"Objective: To determine whether the longevity of England test cricketers is influenced by occupational success, controlling for the influence of social background.
Design: Archival survey.

Setting: England.

Subjects: Those 418 cricketers who played for England in a test match from the first test in 1876 to 1963 when the distinction between amateur and professional status was removed.

Main outcome measures: Length of life.

Results: Survival analysis of players born between 1827 and 1941 (349 dead, 69 alive) showed a significant relation between mortality and year of birth (p<0.001), amateur/professional status (p = 0.042) and the number of test matches played (p = 0.042). Captaining England was not related to survival.

Conclusion: The link between longevity and both social background and occupational success is supported among test match cricketers. Amateur (or 'gentlemen') cricketers from more privileged social backgrounds survived longer than professionals (or 'players'). The most successful cricketers who played in a larger number of tests lived longer than those who played in a smaller number of tests. Captaining England, which could be regarded as a form of occupational 'control', was not associated with longevity.
"

Central aponeurosis tears of the rectus femoris: practical sonographic prognosis

Central aponeurosis tears of the rectus femoris: practical sonographic prognosis: "Objective:

This study is a statistical analysis to establish whether a correlation exists between the level and degree of rectus femoris (RF) central tendon injury and the amount of time that an athlete is unable to participate subsequently, referred to as 'sports participation absence' (SPA).

Design: Causal–comparative study.

Patients: 35 players from two high-level Spanish soccer teams with an injury to the central tendon of the RF based on clinical and ultrasound criteria.

Main Outcome Measure: Ultrasound examination was performed with an 8–2 MHz linear multifrequency transducer. All studies included both longitudinal and transverse RF sections.

Results: At the proximal level the SPA time is 45.1 days when the injury length is 4.0 cm. This value increases by 5.3 days with each 1 cm increase in the length of injury. In the case of distal level injury, SPA time is 32.9 days when the injury length is 3.9 cm. This value increases by 3.4 days with each 1 cm increase. In the total representative sample, SPA time when the injury length is 4.2 cm corresponds to 39.1 days. This value increases by 4.2 days per length unit.

Conclusions: RF central tendon injury at the proximal level is associated with a greater SPA time than at the distal level. Patients with a grade II injury have an SPA time longer than those with a grade I injury whether the injury is located proximal or distal.
"

ORIGINAL INVESTIGATION: Evaluating the Incremental Benefits of Raising High-Density Lipoprotein Cholesterol Levels During Lipid Therapy After Adjustme

ORIGINAL INVESTIGATION: Evaluating the Incremental Benefits of Raising High-Density Lipoprotein Cholesterol Levels During Lipid Therapy After Adjustment for the Reductions in Other Blood Lipid Levels: "

Background The role of high-density lipoprotein cholesterol (HDL-C) as a therapeutic target to prevent cardiovascular (CV) events remains unclear. We examined data from the Framingham Offspring Study from 1975 through 2003 to determine whether increases in HDL-C levels after lipid therapy was started were independently associated with a reduction in CV events.

Methods Using Cox proportional-hazards regression, we evaluated the risk of a CV event associated with changes in blood lipid levels among individuals who started lipid therapy. The independent effect of HDL-C levels on future CV risk (average follow-up, 8 years) was estimated after adjustment for changes in low-density lipoprotein cholesterol, plasma triglycerides, and pretreatment blood lipid levels. Potential confounders (eg, smoking status, weight, and the use of β-blockers) were then added to the model. Interactions between blood lipid levels were also explored.

Results The change in HDL-C level was a strong independent risk factor for CV events (hazard ratio, 0.79 per 5-mg/dL increase; 95% confidence interval, 0.67-0.93) after adjustment for the other lipid changes associated with treatment. This relationship remained stable across a wide range of patient subgroups and did not appear to be associated with a specific drug class. An important interaction was observed: the lower the pretreatment low-density lipoprotein cholesterol level, the greater the impact of raising the HDL-C.

Conclusions Raising HDL-C levels with commonly used lipid medications appears to be an important determinant of the benefits associated with lipid therapy. These results support the further evaluation of therapies to raise HDL-C levels to prevent CV events.

"

ORIGINAL CONTRIBUTION: Surgical Mask vs N95 Respirator for Preventing Influenza Among Health Care Workers: A Randomized Trial

ORIGINAL CONTRIBUTION: Surgical Mask vs N95 Respirator for Preventing Influenza Among Health Care Workers: A Randomized Trial: "

Context Data about the effectiveness of the surgical mask compared with the N95 respirator for protecting health care workers against influenza are sparse. Given the likelihood that N95 respirators will be in short supply during a pandemic and not available in many countries, knowing the effectiveness of the surgical mask is of public health importance.

Objective To compare the surgical mask with the N95 respirator in protecting health care workers against influenza.

Design, Setting, and Participants Noninferiority randomized controlled trial of 446 nurses in emergency departments, medical units, and pediatric units in 8 tertiary care Ontario hospitals.

Intervention Assignment to either a fit-tested N95 respirator or a surgical mask when providing care to patients with febrile respiratory illness during the 2008-2009 influenza season.

Main Outcome Measures The primary outcome was laboratory-confirmed influenza measured by polymerase chain reaction or a 4-fold rise in hemagglutinin titers. Effectiveness of the surgical mask was assessed as noninferiority of the surgical mask compared with the N95 respirator. The criterion for noninferiority was met if the lower limit of the 95% confidence interval (CI) for the reduction in incidence (N95 respirator minus surgical group) was greater than –9%.

Results Between September 23, 2008, and December 8, 2008, 478 nurses were assessed for eligibility and 446 nurses were enrolled and randomly assigned the intervention; 225 were allocated to receive surgical masks and 221 to N95 respirators. Influenza infection occurred in 50 nurses (23.6%) in the surgical mask group and in 48 (22.9%) in the N95 respirator group (absolute risk difference, –0.73%; 95% CI, –8.8% to 7.3%; P = .86), the lower confidence limit being inside the noninferiority limit of –9%.

Conclusion Among nurses in Ontario tertiary care hospitals, use of a surgical mask compared with an N95 respirator resulted in noninferior rates of laboratory-confirmed influenza.

Trial Registration clinicaltrials.gov Identifier: NCT00756574

Published online October 1, 2009 (doi:10.1001/jama.2009.1466).

"

A comparison of sodium calcium edetate (edetate calcium disodium) and succimer (DMSA) in the treatment of inorganic lead poisoning

A comparison of sodium calcium edetate (edetate calcium disodium) and succimer (DMSA) in the treatment of inorganic lead poisoning

Introduction. This article reviews the experimental and clinical studies that have compared the efficacy (impact on urine lead excretion, blood and tissue lead concentrations, resolution of features and survival) of sodium calcium edetate (edetate calcium disodium) and succimer (DMSA) in the treatment of inorganic lead poisoning. It also summarizes the pharmacokinetic and pharmacodynamic aspects and the adverse effects of treatment.

Methods. Medline, Toxline, and Embase were searched for all available years to June 2009.

Pharmacokinetics and pharmacodynamics. The absorption of oral DMSA is more complete than sodium calcium edetate; the latter has to be administered parenterally. Both antidotes are distributed predominantly extracellularly. Sodium calcium edetate is not metabolized, whereas DMSA is extensively metabolized to mixed disulfides of cysteine. The two antidotes have elimination half-lives of less than 60 min. There is no evidence that either antidote crosses the blood-brain barrier to any major extent. Sodium calcium edetate chelates lead by displacement of the central Ca²⁺ ion with Pb²⁺. The nature of the DMSA-lead chelate is less clearly defined. There is evidence that the mixed disulfides of cysteine are the active chelating moiety in humans. If this is the case, this suggests that chelation occurs principally, if not exclusively, in the kidney. The primary source of lead mobilized by sodium calcium edetate is bone with an additional contribution from kidney and liver.

Efficacy. Comparison of the experimental studies is complicated by substantial variations in study design, particularly the antidote dose, the route and duration of treatment, the amount and duration of lead dosing, and lack of direct comparison between antidotes (comparison was usually made with control). In experimental studies that used equimolar and clinically relevant antidote doses and assessed the impact of DMSA and sodium calcium edetate on urine lead excretion and/or blood lead concentrations, similar results were found, though no direct comparison between antidotes was undertaken. DMSA was more effective than sodium calcium edetate in reducing the kidney lead concentration, sodium calcium edetate was more effective than DMSA in reducing bone lead concentrations, and there was no consistently observed effect of chelation therapy on brain lead concentrations in these experimental studies. Only two clinical studies have compared equimolar or similar antidote doses in enhancing urine lead excretion; there was no statistical difference between the antidotes, though both studies had limitations. DMSA and sodium calcium edetate had a comparable impact on lowering blood lead concentrations in a clinical study using similar molar antidote doses.

Adverse effects. Sodium calcium edetate causes dose-related nephrotoxicity. Both agents deplete zinc and copper, the effect on zinc being significantly greater with sodium calcium edetate. A transient increase in hepatic transaminase activity has been reported with both antidotes but appears to be more common with DMSA and neither has been associated with clinically significant hepatic toxicity. Skin lesions during treatment with sodium calcium edetate are unusual and have been attributed to zinc deficiency. DMSA has occasionally been associated with a severe mucocutaneous reaction necessitating discontinuation of therapy.

Conclusions. Oral DMSA and parenteral sodium calcium edetate are both effective chelators of lead. There are currently insufficient data, however, to conclude that either antidote is superior in enhancing lead excretion. Both antidotes resolve the symptoms of moderate and severe lead toxicity rapidly. Although there is greater clinical experience with sodium calcium edetate, particularly in the treatment of lead encephalopathy, oral DMSA may now be considered as an alternative in circumstances where oral therapy is preferable.

Are calcium oxalate crystals involved in the mechanism of acute renal failure in ethylene glycol poisoning?

Are calcium oxalate crystals involved in the mechanism of acute renal failure in ethylene glycol poisoning?

Introduction. Ethylene glycol (EG) poisoning often results in acute renal failure, particularly if treatment with fomepizole or ethanol is delayed because of late presentation or diagnosis. The mechanism has not been established but is thought to result from the production of a toxic metabolite.

Methods. A literature review utilizing PubMed identified papers dealing with renal toxicity and EG or oxalate. The list of papers was culled to those relevant to the mechanism and treatment of the renal toxicity associated with either compound.

Role of metabolites. Although the “aldehyde” metabolites of EG, glycolaldehyde, and glyoxalate, have been suggested as the metabolites responsible, recent studies have shown definitively that the accumulation of calcium oxalate monohydrate (COM) crystals in kidney tissue produces renal tubular necrosis that leads to kidney failure. In vivo studies in EG-dosed rats have correlated the severity of renal damage with the total accumulation of COM crystals in kidney tissue. Studies in cultured kidney cells, including human proximal tubule (HPT) cells, have demonstrated that only COM crystals, not the oxalate ion, glycolaldehyde, or glyoxylate, produce a necrotic cell death at toxicologically relevant concentrations. COM crystal accumulation.In EG poisoning, COM crystals accumulate to high concentrations in the kidney through a process involving adherence to tubular cell membranes, followed by internalization of the crystals.

Mechanism of toxicity. COM crystals have been shown to alter membrane structure and function, to increase reactive oxygen species and to produce mitochondrial dysfunction. These processes are likely to be involved in the mechanism of cell death.

Conclusions. Accumulation of COM crystals in the kidney is responsible for producing the renal toxicity associated with EG poisoning. The development of a pharmacological approach to reduce COM crystal adherence to tubular cells and its cellular interactions would be valuable as this would decrease the renal toxicity not only in late treated cases of EG poisoning, but also in other hyperoxaluric diseases such as primary hyperoxaluria and kidney stone formation.

Vital Signs: Perceptions: What Clown? I Was Talking With My Mom

Vital Signs: Perceptions: What Clown? I Was Talking With My Mom: "In a study, a man in an outlandish outfit on a unicycle was not enough to draw the notice of many cellphone users.


How much do you miss when you are talking on a cell phone?

Researchers at Western Washington University decided to study whether pedestrians engrossed in a phone conversation would notice obvious events around them. “I was trying to think about what kind of distraction we could put out there, and I talked to this student who had a unicycle,” said Ira E. Hyman Jr., a professor ofpsychology. “He said, ‘What’s more, I own a clown suit.’ You don’t have a student who unicycles in a clown suit every day, so you have to take advantage of these things.”

The student, Dustin Randall, donned the suit — purple and yellow, with polka-dot sleeves, red shoes and a red nose — then hopped on the unicycle and pedaled around a square. After pedestrians crossed the square, researchers asked them, “Did you see anything unusual?”

Among pedestrians who were listening to music or walking alone, 1 in 3 replied that they had just seen a clown on a unicycle, according to a report on the study, in the journal Applied Cognitive Psychology. Nearly 60 percent of those who were walking with a friend mentioned the clown. But among people who had been talking on a cellphone, the figure was 8 percent.

When the pedestrians were asked, “Did you see the unicycling clown?” the rates rose — to as high as 71 percent for people walking with a friend. But among those who had been talking on a cellphone, just 25 percent said they had. TARA PARKER-POPE"

Cervical collar or physiotherapy versus wait and see policy for recent onset cervical radiculopathy: randomised trial [RESEARCH]

Cervical collar or physiotherapy versus wait and see policy for recent onset cervical radiculopathy: randomised trial [RESEARCH]: "

Objective To evaluate the effectiveness of treatment with collar or physiotherapy compared with a wait and see policy in recent onset cervical radiculopathy.

Design Randomised controlled trial.

Setting Neurology outpatient clinics in three Dutch hospitals.

Participants 205 patients with symptoms and signs of cervical radiculopathy of less than one month’s duration

Interventions Treatment with a semi-hard collar and taking rest for three to six weeks; 12 twice weekly sessions of physiotherapy and home exercises for six weeks; or continuation of daily activities as much as possible without specific treatment (control group).

Main outcome measures Time course of changes in pain scores for arm and neck pain on a 100 mm visual analogue scale and in the neck disability index during the first six weeks.

Results In the wait and see group, arm pain diminished by 3 mm/week on the visual analogue scale (β=–3.1 mm, 95% confidence interval –4.0 to –2.2 mm) and by 19 mm in total over six weeks. Patients who were treated with cervical collar or physiotherapy achieved additional pain reduction (collar: β=–1.9 mm, –3.3 to –0.5 mm; physiotherapy: β=–1.9, –3.3 to –0.8), resulting in an extra pain reduction compared with the control group of 12 mm after six weeks. In the wait and see group, neck pain did not decrease significantly in the first six weeks (β=–0.9 mm, –2.0 to 0.3). Treatment with the collar resulted in a weekly reduction on the visual analogue scale of 2.8 mm (–4.2 to –1.3), amounting to 17 mm in six weeks, whereas physiotherapy gave a weekly reduction of 2.4 mm (–3.9 to –0.8) resulting in a decrease of 14 mm after six weeks. Compared with a wait and see policy, the neck disability index showed a significant change with the use of the collar and rest (β=–0.9 mm, –1.6 to –0.1) and a non-significant effect with physiotherapy and home exercises.

Conclusion A semi-hard cervical collar and rest for three to six weeks or physiotherapy accompanied by home exercises for six weeks reduced neck and arm pain substantially compared with a wait and see policy in the early phase of cervical radiculopathy.

Trial registration Clinical trials NCT00129714.

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