The Learning Curve for Acoustic Tumor Surgery

Although operative experience is considered to be critically important in the surgical management of acoustic tumors, little objective evidence substantiates this claim. The present study was undertaken to determine whether a learning curve exists for acoustic tumor surgery. The first 96 acoustic tumor patients managed surgically by a new neurotologic team were retrospectively reviewed. A significant improvement (P<.0003; F=6.32) in the ability to achieve good(grade II or better) postoperative facial nerve function was identified. Improving trends for complete resection rate and hearing preservation were documented, and the incidence of cerebrospinal fluid (CSF) leaks declined; however, statistical significance was not achieved. For postoperative facial nerve function, approximately 60 cases were necessary before the new team achieved results similar to those of highly experienced surgeons. The frequencies of complete resection, CSF leaks, hearing preservation, stroke, and mortality were comparable to those of experienced neurotologic teams. The findings of this study may have implications for both patient care and physician training.     

Melanocortin-1-receptor gene and sun sensitivity in individuals without red hair

Susceptibility to sunburn, photoageing, and skin cancer is inversely related to an individual's ability to tan after sun exposure. We examined variants in the melanocortin-1-receptor (MC1R) gene in individuals from Ireland and the UK. We found evidence of an association between the degree of tanning after repeated sun exposure, and the number of variant alleles present. Heterozygotes were intermediate between wild-type individuals and those with two variant alleles. We suggest that MC1R gene status therefore determines sun sensitivity in people without red hair.     

Virulence,phenotype and genotype characteristics of endodontic Enterococcus spp.

Background/aims: Enterococci have been implicated in persistent root canal infections but their role in the infection process remains unclear. This study investigated the virulence, phenotype and genotype of 33 endodontic enterococcal isolates. Methods: Phenotypic tests were conducted for antibiotic resistance, clumping response to pheromone, and production of gelatinase, hemolysin and bacteriocin. Genotype analysis involved polymerase chain reaction amplification of virulence determinants encoding aggregation substances asa and asa373, cytolysin activator cylA, gelatinase gelE, gelatinase‐negative phenotype ef1841/fsrC, adherence factors esp and ace, and endocarditis antigen efaA. Physical DNA characterization involved pulsed‐field gel electrophoresis of genomic DNA, and plasmid analysis. Results: Potential virulence traits expressed included production of gelatinase by Enterococcus faecalis (n = 23), and response to pheromones in E. faecalis culture filtrate (n = 16). Fourteen strains produced bacteriocin. Five strains were resistant to tetracycline and one to gentamicin, whereas all were susceptible to ampicillin, benzylpenicillin, chloramphenicol, erythromycin, fusidic acid, kanamycin, rifampin, streptomycin and vancomycin. Polymerase chain reaction products encoding efaA, ace, and asa were detected in all isolates; esp was detected in 20 isolates, cylA in six isolates, but asa373 was never detected. The gelatinase gene (gelE) was detected in all isolates of E. faecalis (n = 31) but not in Enterococcus faecium (n = 2); a 23.9 kb deletion sequence corresponding to the gelatinase‐negative phenotype was detected in six of the eight E. faecalis isolates that did not produce gelatinase. Pulsed‐field gel electrophoresis and plasmid analyses revealed genetic polymorphism with clonal types evident. Plasmid DNA was detected in 25 strains, with up to four plasmids per strain and a similar (5.1 kb) plasmid occurring in 16 isolates. Conclusions: Phenotypic and genotypic evidence of potential virulence factors were identified in endodontic Enterococcus spp., specifically production of gelatinase and response to pheromones.     

Dry needling: a literature review with implications for clinical practice guidelines

Background:

Wet needling uses hollow-bore needles to deliver corticosteroids, anesthetics, sclerosants, botulinum toxins, or other agents. In contrast, dry needling requires the insertion of thin monofilament needles, as used in the practice of acupuncture, without the use of injectate into muscles, ligaments, tendons, subcutaneous fascia, and scar tissue. Dry needles may also be inserted in the vicinity of peripheral nerves and/or neurovascular bundles in order to manage a variety of neuromusculoskeletal pain syndromes. Nevertheless, some position statements by several US State Boards of Physical Therapy have narrowly defined dry needling as an ‘intramuscular’ procedure involving the isolated treatment of ‘myofascial trigger points’ (MTrPs).

Objectives:

To operationalize an appropriate definition for dry needling based on the existing literature and to further investigate the optimal frequency, duration, and intensity of dry needling for both spinal and extremity neuromusculoskeletal conditions.

Major findings:

According to recent findings in the literature, the needle tip touches, taps, or pricks tiny nerve endings or neural tissue (i.e. ‘sensitive loci’ or ‘nociceptors’) when it is inserted into a MTrP. To date, there is a paucity of high-quality evidence to underpin the use of direct dry needling into MTrPs for the purpose of short and long-term pain and disability reduction in patients with musculoskeletal pain syndromes. Furthermore, there is a lack of robust evidence validating the clinical diagnostic criteria for trigger point identification or diagnosis. High-quality studies have also demonstrated that manual examination for the identification and localization of a trigger point is neither valid nor reliable between-examiners.

Conclusions:

Several studies have demonstrated immediate or short-term improvements in pain and/or disability by targeting trigger points (TrPs) using in-and-out techniques such as ‘pistoning’ or ‘sparrow pecking’; however, to date, no high-quality, long-term trials supporting in-and-out needling techniques at exclusively muscular TrPs exist, and the practice should therefore be questioned. The insertion of dry needles into asymptomatic body areas proximal and/or distal to the primary source of pain is supported by the myofascial pain syndrome literature. Physical therapists should not ignore the findings of the Western or biomedical ‘acupuncture’ literature that have used the very same ‘dry needles’ to treat patients with a variety of neuromusculoskeletal conditions in numerous, large scale randomized controlled trials. Although the optimal frequency, duration, and intensity of dry needling has yet to be determined for many neuromusculoskeletal conditions, the vast majority of dry needling randomized controlled trials have manually stimulated the needles and left them in situ for between 10 and 30 minute durations. Position statements and clinical practice guidelines for dry needling should be based on the best available literature, not a single paradigm or school of thought; therefore, physical therapy associations and state boards of physical therapy should consider broadening the definition of dry needling to encompass the stimulation of neural, muscular, and connective tissues, not just ‘TrPs’.     

Antibiotic resistance gene transfer between Streptococcus gordonii and Enterococcus faecalis in root canals of teeth ex vivo

Multiple bacterial species coexisting in infected root canals might interact, but evidence for interspecies gene transfer is lacking. This study tested the hypothesis that horizontal exchange of antibiotic resistance can occur between different bacterial species in root canals. Transfer of the conjugative plasmid pAM81 carrying erythromycin resistance between 2 endodontic infection-associated species, Streptococcus gordonii and Enterococcus faecalis, was investigated in an ex vivo tooth model. Equal numbers of each species (one with pAM81 and the other plasmid-free) were combined in prepared root canals of sterilized teeth and incubated at 37 degrees C. At 24 and 72 hours, bidirectional interspecies antibiotic resistance gene transfer was evident in microorganisms recovered from teeth; average transfer frequencies from S. gordonii to E. faecalis were 10(-3) transconjugants per donor and from E. faecalis to S. gordonii were 10(-6) and 10(-7) transconjugants per donor at 24 and 72 hours, respectively. Microbial accumulations were observed on root canal walls with scanning electron microscopy. Horizontal genetic exchange in endodontic infections might facilitate adoption of an optimal genetic profile for survival.     

Modeling the Injury Prevention Impact of Mandatory Alcohol Ignition Interlock Installation in All New US Vehicles

Objectives. We estimated the injury prevention impact and cost savings associated with alcohol interlock installation in all new US vehicles.Methods. We identified fatal and nonfatal injuries associated with drinking driver vehicle crashes from the Fatality Analysis Reporting System and National Automotive Sampling System’s General Estimates System data sets (2006–2010). We derived the estimated impact of universal interlock installation using an estimate of the proportion of alcohol-related crashes that were preventable in vehicles < 1 year-old. We repeated this analysis for each subsequent year, assuming a 15-year implementation. We applied existing crash-induced injury cost metrics to approximate economic savings, and we used a sensitivity analysis to examine results with varying device effectiveness.Results. Over 15 years, 85% of crash fatalities (> 59 000) and 84% to 88% of nonfatal injuries (> 1.25 million) attributed to drinking drivers would be prevented, saving an estimated $342 billion in injury-related costs, with the greatest injury and cost benefit realized among recently legal drinking drivers. Cost savings outweighed installation costs after 3 years, with the policy remaining cost effective provided device effectiveness remained above approximately 25%.Conclusions. Alcohol interlock installation in all new vehicles is likely a cost-effective primary prevention policy that will substantially reduce alcohol-involved crash fatalities and injuries, especially among young vulnerable drivers.Despite significant reductions in the 1980s, alcohol-involved motor vehicle crashes (AI-MVCs) remain a significant public health problem.1–3 Since 1994, even as overall fatalities from crashes have declined, AI-MVC fatalities, as a proportion of all traffic fatalities, have remained higher than 30%.1–3 In 2011, 9878 fatalities resulted from a crash with at least 1 intoxicated driver (blood alcohol content [BAC] ≥ 0.08 g/dL).4 AI-MVCs are also a significant economic burden to communities, with societal costs estimated to be as high as $59 billion annually, which is 21% of the total annual economic cost ($277 billion) associated with MVC-related injury.5Previous success reducing fatal and nonfatal injuries resulting from drink driving is largely attributable to successful enforcement of alcohol availability and alcohol-related driving laws (e.g., license suspension, minimum legal drinking age laws, 0.08 grams per deciliter BAC limits, zero tolerance laws, sobriety checkpoints), as well as the general deterrence effect conferred by impaired driving penalties.6–9 However, these laws are difficult to enforce because they rely on police identification of impaired drivers.3 As a result, alcohol-impaired driving arrests are rare, with estimates that an impaired driver drives an average of 80 times before being stopped for driving while intoxicated (DWI).1,2 Even license suspension, which has previously provided the strongest evidence for reducing DWI recidivism, with reductions of impaired driver fatal crash risk by as much as 50%,10–12 has limited impact. Previous studies have indicated that as many as 50% to 75% of offenders continue to operate a vehicle despite license suspension.13–15 Furthermore, half of convicted DWI drivers continue to drive without a license even after they are eligible for reinstatement, citing successful evasion of police during their license suspension period.16,17Difficulty detecting impaired drivers has led to the development of in-vehicle technological solutions that can prevent alcohol-impaired driving, including such devices as alcohol ignition interlocks.1 Current interlock devices are designed as an alcohol breath-testing unit connected to the ignition switch of the vehicle that prevents driving if the driver’s breath contains more than a predetermined limit of alcohol (typically BAC > 0.02 g/dL).18–20 They are used in all 50 states for multiple DWI offenders, either as a Department of Motor Vehicles mandated condition of license reinstatement or as a component of DWI judicial sentencing. Interlocks are highly effective while installed on the vehicle, with a systematic review finding a 67% median reduction in DWI recidivism.20–24 Limited evidence is available examining their associated impact on MVCs, but recent studies suggest that AI-MVCs may also decrease while interlocks are installed.25–27Despite the clear public health benefit and existence of the technology for several decades, widespread interlock use is limited. In 2013, only 300 000 interlock devices were actively in use throughout the United States, representing less than a quarter of DWI offenders.28 Limited usage is thought to result from low DWI conviction rates, state policies restricting interlocks to repeat DWI offenders, and a preference among offenders to have their license suspended rather than install devices that prevent impaired driving.20 The weaknesses in the current enforcement model, combined with technological improvements in interlock devices, has generated interest in interlock use as a primary prevention tool. In 2008, the National Highway Traffic Safety Administration (NHTSA) launched the Driver Alcohol Detection System for Safety (DADSS) program, a 5-year collaborative industry and government program to explore the feasibility, benefits, and public policy challenges associated with widespread use of in-vehicle alcohol detection technologies. Application of alcohol interlocks to all new vehicles is one primary prevention strategy under discussion.Literature examining interlock use as a primary prevention tool is limited. Bjerre et al26 studied the installation of 300 interlocks in commercial vehicles (buses, taxis, trucks) in Sweden, finding that they prevented 3.4 drunk driving trips (BAC > 0.02 g/dL) for every 1000 potential car trips.26 Lahausse and Fildes29 modeled the injury prevention benefit associated with alcohol interlock installation in all newly registered Australian vehicles; they found that interlocks would prevent up to 24% of all fatalities and 11% of serious injuries annually. This study, however, was limited by the inability to analyze comprehensive Australian crash data, necessitating extrapolation of fatality data from a single Australian state, as well as the use of an estimated fatal-to-nonfatal injury ratio for the derivation of serious injury estimates. Furthermore, although these studies demonstrated the potential injury prevention impact of interlocks, no previous studies have analyzed fatal and nonfatal crash data to examine the primary prevention impact within the United States.Our objectives for the present study were (1) to estimate the potential impact on fatalities and nonfatal injuries of alcohol interlock installation in all new vehicles, and (2) to estimate the potential decrease in economic costs associated with injury prevention by a universal alcohol-ignition interlock policy. Such data have the potential to provide a better understanding of how the mandatory installation of alcohol interlocks in new vehicles, as proposed within the DADSS program, might contribute to reducing AI-MVC fatalities and nonfatal injuries.     

Schema-based retrieval processes in young and older adults.

Through two experiments we examined the extent to which the memory performance of different-aged adults was dependent upon the conceptual relationship between the to-be-remembered information and the perspective adopted at retrieval. In both studies, young and old adults read a story from one of two perspectives. They then recalled the story twice: first from the perspective taken at reading and then again from the alternative perspective. It was found that memory performance in both age groups was related to the relevance of the story information to the recall perspective. In addition, the interaction between recall perspective and the relevance of the story units was similar across age groups. This suggests that young and older adults are similarly dependent upon schema-based relations in aiding recall, at least when the memory task has a heavy emphasis on conceptually driven retrieval processes.     

Micronutrient status and leukocyte telomere length in school-age Colombian children

Leukocyte telomere length (LTL) is a biomarker of inflammation and oxidative stress that predicts chronic disease risk. Nutritional factors are related to LTL in adulthood, but these associations are not well characterized in children. We examined whether micronutrient status biomarkers were associated with LTL in school-age children. We conducted a cross-sectional study of 330 boys and 393 girls aged 5–12 years from Bogotá, Colombia. We quantified blood concentrations of hemoglobin, ferritin, zinc, vitamin A, folate, and vitamin B-12; and measured LTL using qPCR in DNA extracted from buffy coat. We estimated mean differences in LTL by quartiles of micronutrient status biomarkers and categories of relevant sociodemographic and anthropometric covariates with the use of linear regression. In girls, plasma vitamin B-12 was positively associated with LTL (adjusted LTL difference between extreme vitamin B-12 quartiles = 0.11; P, trend = 0.02). LTL was also positively associated with birth order in girls (P, trend = 0.02). In boys, LTL was not related to the micronutrient status biomarkers but, unexpectedly, it was positively associated with birth weight (P = 0.02), height-for-age Z score (P, trend = 0.01), and serum C-reactive protein (P, trend = 0.01). LTL is associated with vitamin B-12 status among girls. LTL is also associated with birth weight, height, and C-reactive protein in boys.     

Communication competence, self-care behaviors and glucose control in patients with type 2 diabetes

Objective

To examine the relationship between physician communication competence and A1c control among Hispanics and non-Hispanics seen in primary care practices.

Study design

Observational.

Methods

Direct observation and audio-recording of patient–physician encounters by 155 Hispanic and non-Hispanic white patients seen by 40 physicians in 20 different primary care clinics. Audio-recordings were transcribed and coded to derive an overall communication competence score for the physician. An exit survey was administered to each patient to assess self-care activities and their medical record was abstracted for the most recent glycosylated hemoglobin (A1c) level.

Results

Higher levels of communication competence were associated with lower levels of A1c for Hispanics, but not non-Hispanic white patients. Although communication competence was associated with better self-reported diet behaviors, diet was not associated with A1c control. Across all patients, higher levels of communication competence were associated with improved A1c control after controlling for age, ethnicity and diet adherence.

Conclusions

Physician's communication competence may be more important for promoting clinical success in disadvantaged patients.

Practice implications

Acquisition of communication competence skills may be an important component in interventions to eliminate Hispanic disparities in glucose control.