Center-level outcomes following elective fenestrated endovascular aortic aneurysm repair in the Vascular Quality Initiative database

OBJECTIVE

Hospital volume is associated with mortality after open aortic aneurysm repair. Fenestrated and branched endovascular aortic repair (B-FEVAR) has been increasingly used for repair of complex thoracoabdominal and juxtarenal aneurysms, but evidence of a center-volume relationship is limited. We aimed to measure the association of center volume with in-hospital mortality, postoperative outcomes, and 1-year survival following B-FEVAR.

METHODS

Patients undergoing elective endovascular thoracoabdominal and complex abdominal aneurysm repair with branch intervention (2014-2021) listed within the national Vascular Quality Initiative Thoracic Endovascular Aortic Repair/Complex EVAR database were analyzed. Centers were grouped into quartiles by mean annual procedure volume. Multivariable regression was used to evaluate the effect of center volume on in-hospital mortality adjusting for baseline and procedural characteristics. Kaplan-Meier estimation, log rank test, and mixed effects Cox regression were used to evaluate 1-year survival.

RESULTS

A total of 4302 adult elective F-BEVAR procedures were identified at a total of 163 centers. In-hospital mortality did not differ by hospital volume (quartile [Q]1 = 35/1059 [3.3%]; Q2 = 30/1063 [2.8%]; Q3 = 33/1120 [2.9%]; and Q4 = 44/1060 [4.2%]; P = .308). The high volume group had a higher rate of major complication (Q1 = 14.9%; Q2 = 12.8%; Q3 = 13.3%; and Q4 = 20.1%; adjusted P < .001). Physician-modified grafts were more frequently employed in high-volume centers (Q1 = 4.5%; Q2 = 18.7%; Q3 = 11.3%; and Q4 = 19.2%; P < .001), with a decreased incidence of any endoleak noted at the end of the procedure (Q1 = 34.9%; Q2 = 32.8%; Q3 = 30.0%; and Q4 = 29.0%; P = .003). In the multivariable analysis, in-hospital mortality was not associated with center volume, comparing very low volume to medium- and high-volume centers (odds ratio [95% confidence interval] vs Q4: Q1 = 1.1 [0.6-1.9], Q2 = 0.6 [0.4-1.1], and Q3 = 0.9 [0.5-1.5]; all P > .05). No significant difference was found in 1-year survival between center volume groups.

CONCLUSIONS

In-hospital mortality is not associated with procedure volume within centers performing complex endovascular aortic repair. However, complication rates and endoleak may be associated with procedure volume. Long-term outcomes by annualized procedure volume, specifically graft durability and sac expansion, should be investigated.

Examining the validity of the Delis-Kaplan Executive Function System (D-KEFS) in traumatic brain injury

This study examines the validity of the Delis-Kaplan Executive Function System (D-KEFS) in a traumatic brain injury (TBI) population compared to participants with orthopaedic injuries and normative controls. The utility of the D-KEFS was examined using a between groups design. One hundred patients with mild uncomplicated to severe TBI were recruited from a consecutive cohort of patients admitted as inpatients to a UK Major Trauma Centre and compared to 823 participants from the D-KEFS normative sample and 26 participants with orthopaedic injuries. Data were filtered for performance validity. Sample discrimination was calculated from D-KEFS subtest scores and derived index scores. Sensitivity to TBI severity was established. The TBI participants performed significantly lower on the D-KEFS Trail Making Test, Colour Word Interference, Colour Word Switching, Letter Fluency and Verbal Fluency Category Switching Total Words Correct. The D-KEFS index scores discriminated between TBI, orthopaedic and normative participants with large and moderate effect sizes, respectively. The D-KEFS demonstrated a dose-response relationship with TBI severity. These effects were robust to differences in premorbid intellectual functioning; however, D-KEFS performance was sensitive to performance on tests of mental processing speed. The use of a D-KEFS index score provides a robust and reliable discrimination of TBI patients from healthy control participants. This discrimination is not accounted for by premorbid intellect or the non-specific effects of trauma. The clinical and conceptual implications of these findings are considered.

An evaluation of a trauma-informed educational intervention to enhance therapeutic engagement and reduce coercive practices in a child and adolescent inpatient mental health unit

High-risk behaviours are sometimes encountered in Child and Adolescent inpatient mental health units and can prompt the use of coercive practices to maintain safety. Coercive practices may lead to re-traumatisation of young people and deteriorating therapeutic relationships. Trauma-informed practice (TIP) has successfully reduced coercive practices. While education is identified as foundational to implementation, evaluations of programmes remain minimal. The aim of this study was to explore mental health professionals' views and experiences of a trauma-informed education programme and its likely impact on their approach to practice. Five mental health professionals agreed to participate, four contributed in a focus group and one in an individual interview. Data were analysed thematically using the Braun and Clarke Framework. Three main themes were identified. Firstly, shifting attitudes and perceptions of trauma-informed practice. Participants believed they had developed more compassion towards clients and these attitudes were reflected in their clinical practice. Secondly, challenges associated with trauma-informed practice educational intervention. Staffing issues and shift work made it difficult for participants to attend education sessions regularly. Participants identified barriers to practicing in a trauma-informed manner in the current clinical environment. Finally, the need for interdisciplinary communication and support was identified. Participants saw the need for all professionals, not only nurses, to take responsibility for changing practice, and for stronger support at the organisational level. Trauma-informed practice is crucial to recovery-focused mental health nursing practice. These findings highlight the importance of TIP education and suggest areas for further improvement to enhance positive mental health outcomes for young people.

Cognitive Outcome After Complicated Mild Traumatic Brain Injury: A Literature Review and Meta-Analysis

Cognitive outcome for mild traumatic brain injury (mTBI) with positive brain imaging (complicated mTBI) was compared with that for mTBI with normal imaging (uncomplicated mTBI) and with moderate to severe TBI, using meta-analysis. Twenty-three studies utilizing objective neurocognitive tests were included in the analysis. At less than 3 months post-injury, complicated mTBI was associated with poorer cognitive outcomes than uncomplicated mTBI, but deficits were not comparable to those with moderate-severe TBI. After 3 months post-injury, a similar pattern was detected. Beyond 3 months, deficits in complicated mTBI relative to those with uncomplicated mTBI were present in processing speed, memory, executive function, and language, although the latter may be the result of reduced semantic fluency. The effect size of deficits in these domains was more marked in moderate-severe TBI. The available data support the use of complicated mTBI as a distinct classification in the prediction of cognitive outcome. The extent of cognitive deficit in complicated mTBI was small and unlikely to cause significant disability. However, patients with complicated mTBI constitute a broad category encompassing individuals who may differ markedly in the nature and extent of intracranial imaging abnormality, and further studies are warranted. Limitations of the available studies include small, selected samples; variations in TBI severity classification; absence of validity ("effort") testing; differing imaging methodology; and lack of long-term follow-up.

Cold Spray: Over 30 Years of Development Toward a Hot Future

Cold Spray (CS) is a deposition process, part of the thermal spray family. In this method, powder particles are accelerated at supersonic speed within a nozzle; impacts against a substrate material triggers a complex process, ultimately leading to consolidation and bonding. CS, in its modern form, has been around for approximately 30 years and has undergone through exciting and unprecedented developmental steps. In this article, we have summarized the key inventions and sub-inventions which pioneered the innovation aspect to the process that is known today, and the key breakthroughs related to the processing of materials CS is currently mastering. CS has not followed a liner path since its invention, but an evolution more similar to a hype cycle: high initial growth of expectations, followed by a decrease in interest and a renewed thrust pushed by a number of demonstrated industrial applications. The process interest is expected to continue (gently) to grow, alongside with further development of equipment and feedstock materials specific for CS processing. A number of current applications have been identified the areas that the process is likely to be the most disruptive in the medium-long term future have been laid down.

Hip Abductor Strength Asymmetry: Relationship to Upper Extremity Injury in Professional Baseball Players

BACKGROUND

Hip strength is an important factor for control of the lumbo-pelvic-hip complex. Deficits in hip strength may affect throwing performance and contribute to upper extremity injuries.

HYPOTHESIS

Deficits in hip abduction isometric strength would be greater in those who sustained an upper extremity injury and hip strength would predict injury incidence.

STUDY DESIGN

Prospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Minor League baseball players (n = 188, age = 21.5 ± 2.2 years; n = 98 pitchers; n = 90 position players) volunteered. Hip abduction isometric strength was assessed bilaterally with a handheld dynamometer in side-lying position, expressed as torque using leg length (N·m). Hip abduction strength asymmetry was represented by [(trail leg/lead leg) × 100]. Overuse or nontraumatic throwing arm injuries were prospectively tracked. Poisson regression models were used to estimate relative risk ratios associated with hip asymmetry; confounders, including history of prior overuse injury in the past year, were included.

RESULTS

Hip abduction asymmetry ranged from 0.05% to 57.5%. During the first 2 months of the season, 18 players (n = 12 pitchers) sustained an upper extremity injury. In pitchers, for every 5% increase in hip abduction asymmetry, there was a 1.24 increased risk of sustaining a shoulder or elbow injury. No relationship between hip abduction strength and injury was observed for position players.

CONCLUSION

Hip abduction asymmetry in pitchers was related to subsequent upper extremity injuries. The observed risk ratio indicates that hip abduction asymmetry may contribute a significant but small increased risk of injury.

CLINICAL RELEVANCE

Hip abduction muscle deficits may affect pitching mechanics and increase arm stress. Addressing hip asymmetry deficits that exceed 5% may be beneficial in reducing upper extremity injury rates in pitchers.

Emergency Tracheal Intubation in Patients with COVID-19: A Single-center, Retrospective Cohort Study

INTRODUCTION

The objective of this study was to compare airway management technique, performance, and peri-intubation complications during the novel coronavirus pandemic (COVID-19) using a single-center cohort of patients requiring emergent intubation.

METHODS

We retrospectively collected data on non-operating room (OR) intubations from February 1-April 23, 2020. All patients undergoing emergency intubation outside the OR were eligible for inclusion. Data were entered using an airway procedure note integrated within the electronic health record. Variables included level of training and specialty of the laryngoscopist, the patient's indication for intubation, methods of intubation, induction and paralytic agents, grade of view, use of video laryngoscopy, number of attempts, and adverse events. We performed a descriptive analysis comparing intubations with an available positive COVID-19 test result with cases that had either a negative or unavailable test result.

RESULTS

We obtained 406 independent procedure notes filed between February 1-April 23, 2020, and of these, 123 cases had a positive COVID-19 test result. Residents performed fewer tracheal intubations in COVID-19 cases when compared to nurse anesthetists (26.0% vs 37.4%). Video laryngoscopy was used significantly more in COVID-19 cases (91.1% vs 56.8%). No difference in first-pass success was observed between COVID-19 positive cases and controls (89.4% vs. 89.0%, p = 1.0). An increased rate of oxygen desaturation was observed in COVID-19 cases (20.3% vs. 9.9%) while there was no difference in the rate of other recorded complications and first-pass success.

DISCUSSION

An average twofold increase in the rate of tracheal intubation was observed after March 24, 2020, corresponding with an influx of COVID-19 positive cases. We observed adherence to society guidelines regarding performance of tracheal intubation by an expert laryngoscopist and the use of video laryngoscopy.

Validation of the Neuropsychological Assessment Battery Screening Module (NAB-SM) in patients with traumatic brain injury

This study cross-validates the screening module of the Neuropsychological Assessment Battery (NAB-SM) with a battery of well validated neuropsychological tests (Convergent Validity Test Battery: CVTB) in a Traumatic Brain Injury (TBI) population. Forty-four participants with "mild-complicated" to "severe" TBI were recruited from a cohort of patients attending an outpatient clinic at a UK major trauma center. The NAB-SM Total Index score and an abbreviated short-form, from which a TBI Index was derived, both showed good classification accuracy in predicting impairment as measured by the CVTB mean score. These indices also accurately identified impairment as defined by the base rate of low scores across individual CVTB indices measuring mental processing speed, working memory, memory and executive functioning. The NAB-SM and its derived TBI index therefore have significant utility as a cognitive screening tool for use in either inpatient (acute) or outpatient TBI populations.

P2Y12 Inhibitor Monotherapy After a Short Dual Antiplatelet Therapy Versus Standard-Term Dual Antiplatelet Therapy in Patients Undergoing Percutaneous Coronary Intervention: A Contemporary Meta-Analysis

BACKGROUND AND OBJECTIVES

Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) reduces the incidence of thrombotic events but increases the risk of bleeding, which is associated with a substantial and durable risk of death and could offset the benefits of a reduction in thrombotic events. P2Y12 inhibitor monotherapy after short-term DAPT could be an option to reduce the risk of bleeding. We carried out a meta-analysis comparing P2Y12 inhibitor monotherapy after short-term DAPT with standard-term DAPT in patients undergoing PCI.

METHODS

We searched the PubMed and EMBASE databases through 11 April 2020. Two authors independently reviewed and selected eligible trials. The DerSimonian-Laird method with the binary random-effects model was used to calculate the relative risk (RR) with 95% confidence interval (CI).

RESULTS

Five trials involving 23,762 patients were included in the final analyses; four were open-label trials, while the TWILIGHT trial was double-blinded. Ticagrelor was used in three trials, and the other two trials included several P2Y12 inhibitors. P2Y12 inhibitor monotherapy after short-term DAPT significantly reduced the bleeding events, defined as Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding and Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding, by 39% (RR 0.61, 95% CI 0.38-0.99; p = 0.045) and 46% (RR 0.56, 95% CI 0.42-0.73; p < 0.001), respectively. A significant reduction in cardiovascular death was associated with P2Y12 inhibitor monotherapy after short-term DAPT (RR 0.75, 95% CI 0.58-0.98; p = 0.037; I² = 0). No significant difference in all-cause mortality, myocardial infarction, stroke, or definite or probable stent thrombosis was observed.

CONCLUSIONS

This meta-analysis showed a significantly lowered risk of major bleeding and similar benefits of P2Y12 inhibitor monotherapy after short-term DAPT compared with standard-term DAPT in patients undergoing PCI.

Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

Motivating HIV Providers in Vietnam to Learn: A Mixed-Methods Analysis of a Mobile Health Continuing Medical Education Intervention

BACKGROUND

The Mobile Continuing Medical Education Project (mCME V.2.0) was a randomized controlled trial designed to test the efficacy of a text messaging (short message service [SMS])-based distance learning program in Vietnam that included daily quiz questions, links to readings and online courses, and performance feedback. The trial resulted in significant increases in self-study behaviors and higher examination scores for intervention versus control participants.

OBJECTIVE

The objective of this mixed-methods study was to conduct qualitative and quantitative investigations to understand participants' views of the intervention. We also developed an explanatory framework for future trial replication.

METHODS

At the endline examination, all intervention participants completed a survey on their perspectives of mCME and self-study behaviors. We convened focus group discussions to assess their experiences with the intervention and attitudes toward continuing medical education.

RESULTS

A total of 48 HIV specialists in the intervention group completed the endline survey, and 30 participated in the focus group discussions. Survey and focus group data suggested that most clinicians liked the daily quizzes, citing them as convenient mechanisms to convey information in a relevant manner. A total of 43 of the 48 (90%) participants reported that the daily quizzes provided motivation to study for continuing medical education purposes. Additionally, 83% (40/48) of intervention participants expressed that they were better prepared to care for patients with HIV in their communities, compared with 67% (32/48) at baseline. Participation in the online coursework component was low (only 32/48, 67% of intervention participants ever accessed the courses), but most of those who did participate thought the lectures were engaging (26/32, 81%) and relevant (29/32, 91%). Focus group discussions revealed that various factors influenced the clinicians' decision to engage in higher learning, or "lateral learning," including the participant's availability to study, professional relevance of the topic area, and feedback. These variables serve as modifying factors that fit within an adapted version of the health belief model, which can explain behavior change in this context.

CONCLUSIONS

Qualitative and quantitative endline data suggested that mCME V.2.0 was highly acceptable. Participant behaviors during the trial fit within the health belief model and can explain the intervention's impact on improving self-study behaviors. The mCME platform is an evidence-based approach with the potential for adoption at a national scale as a method for promoting continuing medical education.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02381743; https://clinicaltrials.gov/ct2/show/NCT02381743.

Characterizing grassland fire activity in the Flint Hills region and air quality using satellite and routine surface monitor data

Prescribed grassland fires in the Flint Hills region of central Kansas and northern Oklahoma are a common tool for land management. Local to regional scale impacts on air quality from grassland fires in this region are not well understood, which is important as these types of prescribed fires may increase in the future to preserve broader areas of native grasses in the central U.S. Routine air quality and deposition measurements from sites in and near the Flint Hills were examined for coincident increases during periods of increased prescribed grassland fires. Prescribed fire activity in this region was quantified using satellite detections and multiple publicly available data products of area burned information. March and April comprise over half (41 to 93%) of all annual fire detections in the Flint Hills region seen from satellites between 2007 and 2018 excluding drought years. Annual total fire detections in this region range between 1 and 12 thousand and account for approximately 3% of all fire detections in the contiguous U.S. Annual acres burned ranged from 0.2 to 2 million acres based on U.S. EPA's National Emission Inventory, which accounts for 4 to 38% of grasslands in the area. A comparison of weekly standardized anomalies suggests a relationship between periods of increased grassland fire activity and elevated levels of PM_2.5 organic carbon, elemental carbon, and potassium. Daily 1-hr maximum ozone (O₃), ammonia (NH₃), sulfur dioxide (SO₂), and oxidized nitrogen gases measured at Konza Prairie also had increased levels when prescribed grassland fire activity was highest. This detailed characterization of prescribed fire activity in the Flint Hills and associated air quality impacts will benefit future efforts to understand changes in atmospheric composition due to changing land management practices.

Risk Factors Associated With Low Back Pain in Golfers: A Systematic Review and Meta-analysis

Context:

Low back pain is common in golfers. The risk factors for golf-related low back pain are unclear but may include individual demographic, anthropometric, and practice factors as well as movement characteristics of the golf swing.

Objective:

The aims of this systematic review were to summarize and synthesize evidence for factors associated with low back pain in recreational and professional golfers.

Data Sources:

A systematic literature search was conducted using the PubMed, CINAHL, and SPORTDiscus electronic databases through September 2017.

Study Selection:

Studies were included if they quantified demographic, anthropometric, biomechanical, or practice variables in individuals with and without golf-related low back pain.

Study Design:

Systematic review and meta-analysis.

Level of Evidence:

Level 3.

Data Extraction:

Studies were independently reviewed for inclusion by 2 authors, and the following data were extracted: characterization of low back pain, participant demographics, anthropometrics, biomechanics, strength/flexibility, and practice characteristics. The methodological quality of studies was appraised by 3 authors using a previously published checklist. Where possible, individual and pooled effect sizes of select variables of interest were calculated for differences between golfers with and without pain.

Results:

The search retrieved 73 articles, 19 of which met the inclusion criteria (12 case-control studies, 5 cross-sectional studies, and 2 prospective longitudinal studies). Methodological quality scores ranged from 12.5% to 100.0%. Pooled analyses demonstrated a significant association between increased age and body mass and golf-related low back pain in cross-sectional/case-control studies. Prospective data indicated that previous history of back pain predicts future episodes of pain.

Conclusion:

Individual demographic and anthropometric characteristics may be associated with low back pain, but this does not support a relationship between swing characteristics and the development of golf-related pain. Additional high-quality prospective studies are needed to clarify risk factors for back pain in golfers.

Risk and protective factors for falls on stairs in young children: multicentre case-control study

AIM

To investigate risk and protective factors for stair falls in children aged <5 years.

METHODS

Multicentre case-control study at hospitals, minor injury units and general practices in and around four UK study centres. Cases were children with medically attended stair fall injuries. Controls were matched on age, sex, calendar time and study centre. A total of 610 cases and 2658 controls participated.

RESULTS

Cases' most common injuries were bangs on the head (66%), cuts/grazes not requiring stitches (14%) and fractures (12%). Parents of cases were significantly more likely not to have stair gates (adjusted OR (AOR) 2.50, 95% CI 1.90 to 3.29; population attributable fraction (PAF) 21%) or to leave stair gates open (AOR 3.09, 95% CI 2.39 to 4.00; PAF 24%) both compared with having closed stair gates. They were more likely not to have carpeted stairs (AOR 1.52, 95% CI 1.09 to 2.10; PAF 5%) and not to have a landing part-way up their stairs (AOR 1.34, 95% CI 1.08 to 1.65; PAF 18%). They were more likely to consider their stairs unsafe to use (AOR 1.46, 95% CI 1.07 to 1.99; PAF 5%) or to be in need of repair (AOR 1.71, 95% CI 1.16 to 2.50; PAF 5%).

CONCLUSION

Structural factors including having landings part-way up the stairs and keeping stairs in good repair were associated with reduced stair fall injury risk. Family factors including having stair gates, not leaving gates open and having stair carpets were associated with reduced injury risk. If these associations are causal, addressing these factors in housing policy and routine child health promotion could reduce stair fall injuries.

Use of high-fidelity simulation to improve communication skills regarding death and dying: a qualitative study

OBJECTIVES

The objectives of this study were to explore medical students' experiences of communicating with patients and their carers about death and dying, and to assess whether using high-fidelity simulation improved students' confidence in discussing cardiopulmonary resuscitation.

METHODS

This qualitative study was carried out at a hospital in the south of England. Participants were 7 final-year medical students. Tutorials were developed using high-fidelity simulation to teach communication skills regarding discussion of cardiopulmonary resuscitation with patients and carers. Scenarios involved a simulated ward environment, a high-fidelity simulation mannequin and actor playing the role of a carer. Data were collected through joint interviews carried out by one researcher which were audio recorded and transcribed verbatim. The same researcher analysed the data using framework analysis.

RESULTS

Students reported a lack of experience observing conversations with patients and carers about death and dying. They also reported a lack of opportunities to interact with dying patients during their training. Barriers reported by students included healthcare professionals' and patients' attitudes. Students reported a lack of confidence and preparedness to have consultations with patients and carers about death, dying and cardiopulmonary resuscitation as junior doctors. They perceived role-play scenarios observed by their peers to be stressful, and this detracted from the learning experience. Students reported that the high-fidelity simulation scenarios were more realistic than low-fidelity ('role-play') scenarios. This improved the learning gained from the sessions and improved confidence among some students.

CONCLUSIONS

This study has suggested that high-fidelity simulation may be a useful adjunct for undergraduate communication skills training in palliative medicine. Further research is required to assess whether improvements in confidence described by students in this study translate to discernible improvements in competence, and whether using high-fidelity simulation in this setting is cost-effective.

Perforated hollow-core optical waveguides for on-chip atomic spectroscopy and gas sensing

A hollow-core waveguide structure for on-chip atomic spectroscopy is presented. The devices are based on Anti-Resonant Reflecting Optical Waveguides and may be used for a wide variety of applications which rely on the interaction of light with gases and vapors. The designs presented here feature short delivery paths of the atomic vapor into the hollow waveguide. They also have excellent environmental stability by incorporating buried solid-core waveguides to deliver light to the hollow cores. Completed chips were packaged with an Rb source and the F = 3 ≥ F' = 2, 3, 4 transitions of the D2 line in ⁸⁵Rb were monitored for optical absorption. Maximum absorption peak depths of 9% were measured.

Brain natriuretic peptide and NT-proBNP levels reflect pulmonary artery systolic pressure in trekkers at high altitude

Our objective was to evaluate the utility of the natriuretic peptides BNP (brain natriuretic peptide) and NT-proBNP as markers of pulmonary artery systolic pressure (PASP) in trekkers ascending to high altitude (HA). 20 participants had BNP and NT-proBNP assayed and simultaneous echocardiographic assessment of PASP performed during a trek to 5150 m. PASP increased significantly (p=0.006) with ascent from 24+/-4 to 39+/-11 mm Hg at 5150 m. At 5150 m those with a PASP>/=40 mm Hg (n=8) (versus those with PASP<40 mm Hg) had higher post-exercise BNP (pg/ml): 54.5+/-36 vs. 13.4+/-17 (p=0.012). Their resting BNP at 5150 m was also higher: 57.3+/-43.4 vs. 12.6+/-13 (p=0.017). In those with a pathological (>/=400 pg/ml) rise in NT-proBNP at 5150 m (n=4) PASP was significantly higher: 45.9+/-7.5 vs. 32.2+/-6.2 mm Hg (p=0.015). BNP and NT-proBNP may reflect elevated PASP, a central feature of high altitude pulmonary oedema, at HA.

Reducing the cost of dietary assessment: self-completed recall and analysis of nutrition for use with children (SCRAN24)

BACKGROUND

Self-Completed Recall and Analysis of Nutrition (scran24) is a prototype computerised 24-h recall system for use with 11-16 year olds. It is based on the Multiple Pass 24-h Recall method and includes prompts and checks throughout the system for forgotten food items.

METHODS AND RESULTS

The development of scran24 was informed by an extensive literature review, a series of focus groups and usability testing. The first stage of the recall is a quick list where the user is asked to input all the foods and drinks they remember consuming the previous day. The quick list is structured into meals and snacks. Once the quick list is complete, additional information is collected on each food to determine food type and to obtain an estimate of portion size using digital images of food. Foods are located within the system using a free text search, which is linked to the information entered into the quick list. A time is assigned to each eating occasion using drag and drop onto a timeline. The system prompts the user if no foods or drinks have been consumed within a 3-h time frame, or if fewer than three drinks have been consumed throughout the day. The food composition code and weight (g) of all items selected are automatically allocated and stored. Nutritional information can be generated automatically via the scran24 companion Access database.

CONCLUSIONS

scran24 was very well received by young people and was relatively quick to complete. The accuracy and precision was close to that of similar computer-based systems currently used in dietary studies.

Severe acute mountain sickness, brain natriuretic peptide and NT-proBNP in humans

AIM

To examine the response of brain natriuretic peptide (BNP) and NT-proBNP to high altitude (HA) both at rest and following exercise.

METHODS

We measured NT-proBNP and BNP and Lake Louise (LL) acute mountain sickness (AMS) scores in 20 subjects at rest in Kathmandu (Kat; 1300 m), following exercise and at rest at 4270 and 5150 m.

RESULTS

BNP and NT-proBNP (pg ml(-1) , mean ± SEM) rose significantly from Kat (9.2 ± 2 and 36.9 ± 6.6, respectively) to arrival at 4270 m after exercise (16.6 ± 4 and 152 ± 56.1, P=0.008 and P<0.001, respectively) and remained elevated the next morning at rest (28.9 ± 9 and 207.4 ± 65.1, P = 0.004 and P<0.001 respectively). At 5150, immediately following ascent/descent to 5643 m, BNP and NT-proBNP were 32.3 ± 8.8 and 301.1 ± 96.3 (P=0.003 and P<0.001 vs. Kat, respectively) and at rest the following morning were 33.3 ± 9.7 and 258.9 ± 89.5 (P=0.008 and P=0.001 vs. Kat respectively). NT-proBNP and BNP correlated strongly at 5150 m (ρ 0.905, P<0.001 and ρ 0.914, P<0.001 for resting and post-exercise samples respectively). At 5150 m, BNP levels were significantly higher among the four subjects with severe (LL score>6) AMS (58.4 ± 18.7) compared with those without (BNP 22.7 ± 8.6, P=0.048). There were significant correlations between change in body water from baseline to 5150 m with both BNP and NT-proBNP (ρ 0.77, P=0.001, ρ 0.745, P=0.002 respectively).

CONCLUSION

In conclusion, these data suggest that BNP and NT-proBNP increase with ascent to HA both after exercise and at rest. We also report the novel finding that BNP is significantly greater in those with severe AMS at 5150 m.

Integrated ARROW waveguides with hollow cores

We report the design, fabrication, and demonstration of antiresonant reflecting optical (ARROW) waveguides with hollow cores. We describe the design principles to achieve low waveguide loss in both transverse and lateral directions. A novel fabrication process using silicon dioxide and silicon nitride layers as well as sacrificial polyimide core layers was developed. Optical characterization of 3.5mum thick waveguides with air cores was carried out. We demonstrate single-mode propagation through these hollow ARROW waveguides with propagation loss as low as 6.5cm-1 and mode cross sections down to 6.7mum2. Applications of these waveguides to sensing and quantum communication are discussed.

A distinctive pediatric renal neoplasm characterized by epithelioid morphology, basement membrane production, focal HMB45 immunoreactivity, and t(6;11)(p21.1;q12) chromosome translocation

We report two cases of a hitherto undescribed pediatric renal neoplasm that is distinctive at the morphological, immunohistochemical, ultrastructural, and cytogenetic levels. On light microscopy, the tumors are composed of nests of polygonal, clear to eosinophilic cells associated with a subpopulation of smaller cells that surround hyaline material. Despite their epithelioid morphology, these tumors do not label immunohistochemically for epithelial markers but instead label focally for melanocytic markers HMB45 and Melan A. The hyaline material is positive with periodic acid-Schiff and methenamine-silver histochemical stains, and labels immunohistochemically for type 4 collagen. Ultrastructural examination confirms that it represents basement membrane material. Cytogenetic analysis reveals the identical t(6;11)(p21.1;q12) chromosome translocation as the sole abnormality in these two tumors, confirming their identity and distinctive nature.

Comparison of contrast sensitivity, visual acuity, and Humphrey visual field testing in patients with glaucoma

PURPOSE

To investigate the relationship between large-letter contrast sensitivity, high-contrast visual acuity, and visual field defects in patients with glaucoma.

METHODS

Patients with a diagnosis of glaucoma, glaucoma suspect, or ocular hypertension whose visual acuity was 20/40 (logMAR = 0.3) on better were included in the study. Visual acuity was measured using the Lighthouse visual acuity charts. Contrast sensitivity was measured using the Pell-Robson (PR) chart. The mean depression (MD) score from the most recent Humphrey visual field was used to quantify the visual field defect.

RESULTS

A total of 120 eyes were studied. The PR contrast sensitivity score correlated more strongly with the MD of the visual field (r = .589, P < .001) than did the logMAR visual acuity (r = .193, P = .035). When just the eyes with open-angle glaucoma were considered (N = 54), the correlation was even greater for the PR score (r = .638). In ocular hypertensive eyes (N = 25), the correlations to PR and logMAR were not that different (r = .394 for PR, r = .303 for logMAR). Pseudophakic eyes did not show as strong a correlation (r = .335) as did phakic eyes (r = .591).

CONCLUSION

For glaucomatous eyes with visual acuity of 20/40 or better, a decrease in the contrast sensitivity correlates with increased visual field loss. We speculate that this decrease in contrast sensitivity in glaucoma patients may account for their complaints of poor vision despite normal or near normal visual acuity.

Pathology in the Hundred Acre Wood: a neurodevelopmental perspective on A.A. Milne

Abstract

Somewhere at the top of the Hundred Acre Wood a little boy and his bear play. On the surface it is an innocent world, but on closer examination by our group of experts we find a forest where neurodevelopmental and psychosocial problems go unrecognized and untreated.

Trochanteric non-union in revision total hip arthroplasty: does it matter?

The aims of this study were to assess whether trochanteric non-union is an important factor in revision total hip arthroplasty in terms of postoperative morbidity. We studied prospectively 97 consecutive patients undergoing revision total hip arthroplasty in the years 1992-1996. All operations were performed by one surgeon through a Charnley trans-trochanteric approach. The patients were followed-up over a period of 1-4 years and at 12 months postsurgery were assessed using a modified scoring system devised by D'Aubigne. Anatomical union of the greater trochanter was assessed by an anterior-posterior pelvic radiograph at 12 months to decide if the greater trochanter was united in the correct anatomical position. The trochanteric non-union rate was 18.5% (18 out of 97 patients). There was no significant difference between the patients in terms of pain, function and satisfaction scores at one year between those with trochanteric union and those without. This study suggests that trochanteric non-union post revision total hip arthroplasty is not a cause of increased morbidity.

Health care coverage of high school athletics in South Carolina: does school size make a difference?

Despite an apparently high injury rate, medical coverage available to these high school athletes is often not immediately present during practice and games. The purpose of the present study was to examine the current conditions of health care coverage and delivery to the football program and associated athletic departments in the public and private high schools in South Carolina. Additionally, the relationship between student enrollment and medical coverage was examined. A survey, based upon previously utilized instruments, was sent to the athletic directors at the public and private high schools with interscholastic football programs in South Carolina. The survey included questions pertaining to the medical coverage, including personnel, equipment, and record systems, for football practices and games. Based upon the results of the survey, a majority of high schools in South Carolina appear to have adequate sports medicine coverage and compare favorably with the results of similar data from other states. The medical coverage does significantly vary depending upon the enrollment size of the high school. In spite of this finding, the health care provided high school athletes is often inconsistent and training and equipment required for basic first aid is often absent.

Genotype dependence of hepatitis C virus load measurement in commercially available quantitative assays

Standardization and genotype independence of methods used to quantify hepatitis C virus (HCV) RNA in clinical specimens are necessary for accurate assessment of the role of HCV quantitation as a prognostic marker for HCV infection and monitoring of the response to antiviral treatment. Commercially available methods used to measure HCV loads include PCR-based (Roche Monitor) and hybridization-based (Quantiplex bDNA-2) methods. Recently, a new version of the Roche Monitor assay (version 2.0) has become available; it has been modified to achieve more equal quantitation of different HCV genotypes. Consistent with previous reports, Roche Monitor version 1.0 substantially underestimated concentrations of RNA transcripts of types 2b, 3a, 4a, 5a, and 6a and virus loads in individuals infected with genotypes 2 to 6 relative to reference tests. However, version 2.0 achieved equivalent quantitation of each genotype over a narrow quantitative range (10(3) to 5 x 10(5) copies of RNA/ml) but significantly underestimated RNA concentrations above this range. The assay showed an equivalent inability to quantify high levels of HCV RNA in plasma samples, and this was responsible for the falsely narrow range of virus loads detected in HCV-infected individuals. In contrast, the Chiron bDNA-2 assay could only measure RNA concentrations in the upper quantitative range (2 x 10(5) to 5 x 10(7) copies of RNA/ml) but showed equivalent sensitivity for genotypes 1 to 5; however, concentrations of type 6a RNA transcripts and virus loads in clinical specimens from individuals infected with type 6a were underestimated by a factor of 2 to 4. Differences were observed between PCR- and hybridization-based assays in their relative quantitation of HCV RNA transcripts and HCV genomic RNA, which may cause problems with the use of transcripts for interassay calibration.

An evaluation of the nurse practitioner role in a major rural emergency department

The purpose of this pilot study was to investigate whether nurse practitioners are able to provide a level of primary health service applicable to remote/isolated settings in wound management and treatment of blunt limb trauma. It was hypothesized that there would be no significant difference in the quality of care, or the level of client satisfaction, provided by the medical officers and the nurse practitioners in the study. Two groups participated in the study, nurse practitioners and medical officers. The study used a randomized trial design. Data were collected using quantitative and qualitative methods. Two hundred and thirty-two clients participated in the study. Of this number 63 were supervised cases in the pilot trial. In the randomized trial participants were distributed between nurse practitioners and medical officers (n = 169), of which 91 were randomized to medical officers and 78 to nurse practitioners. Telephone interviews were conducted to evaluate client satisfaction. The majority of study participants were surveyed for client satisfaction (n = 132). This represents approximately 78% of the randomized sample and multivariate analysis was carried out on the data. Study results indicate that there were no significant differences between the two groups in relation to client satisfaction. Very positive outcomes of treatment were consistent across groups in the study. The study also found that there was strong support for the role of the nurse practitioner in the rural emergency setting. Recommendations include further research to measure the efficacy of nurse practitioners utilizing the selected competencies in remote/isolated settings.

cDNA cloning, in vitro expression, and biochemical characterization of cholinesterase 1 and cholinesterase 2 from amphioxus--comparison with cholinesterase 1 and cholinesterase 2 produced in vivo

We have isolated cDNAs coding for the complete amino acid sequences of cholinesterase 1 (ChE1) and cholinesterase 2 (ChE2) from amphioxus. Both ChE transcripts have the characteristics of H-type catalytic subunits, which are inserted in the membrane via an ethanolamine-glycan-phosphatidylinositol anchor. The members of the catalytic triad of ChEs, the three pairs of cysteine residues involved in intrachain disulfide bonding, a cysteine near the carboxy terminal of both sequences, which could mediate interchain disulfide bonding, and 11 of the 14 aromatic amino acids that line the catalytic gorge of AChE are conserved. A remarkable difference between the two enzymes is in the region of the acyl-binding pocket, which plays an important role in determining substrate specificity in cholinesterases. ChE2 contains a sequence that resembles the acyl pocket of invertebrate ChE, while the acyl-binding site of ChE1 is novel. There are also differences between the two enzymes in the peripheral anionic site, which mediates inhibition by certain ligands. In vitro expression in COS-7 cells demonstrates that ChE2 hydrolyzes acetylthiocholine almost exclusively, while ChE1 hydrolyzes both acetylthiocholine and butyrylthiocholine. Both enzymes are inhibited comparably by BW284c51, but ChE1 is considerably more resistant to inhibition by propidium, ethopropazine, and eserine than is ChE2. Velocity sedimentation indicates that ChE1 and ChE2 are present as amphiphilic and nonamphiphilic G2 forms in vivo and in vitro. Another molecular form, which sediments at 17 S, is also present in vivo. Nondenaturing gel electrophoresis in conjunction with digestion by phosphatidylinositol-specific phospholipase C demonstrates that the vast majority of ChE1 and ChE2 is present as ethanolamine-glycan-phosphatidylinositol-anchored G2 forms in vivo. ChE1 also possesses an ethanolamine-glycan-phosphatidylinositol-anchor in vitro; however, ChE2 produced in vitro could not be detected on nondenaturing gels.

Rupture of pectoralis major during parallel bar dips: case report and review

Rupture of the pectoralis major muscle is an uncommon athletic injury that can result in both functional and cosmetic deficiency. To date, most ruptures occurring in athletes have occurred while performing bench press or overhead lifting maneuvers. We describe a case of a pectoralis major rupture occurring while performing weighted parallel bar dips. Despite the popularity of this exercise, injuries associated with this exercise are infrequently reported. This injury can be easily detected by having the patient perform specific maneuvers on physical examination to accentuate any defect that may be present. In most cases, this injury is surgically repaired, although conservative treatment can be a successful option. Treatment options are discussed and recommendations given. A partial or complete tear of the pectoralis major muscle is a rare event and is often not easily detected on physical examination. Surgical repair is currently recommended to restore previous levels of strength and to correct the resulting cosmetic defect. Repair is rarely necessary to perform the normal activities of daily living.

The effect of treatment with alpha-interferon on hepatitis G/GBV-C viraemia. The CONSTRUCT Group

BACKGROUND

Hepatitis G virus (HGV) or GBV-C is frequently detected in patients co-infected with hepatitis C virus (HCV). This study investigated host and virologic factors influencing the response to HGV/GBV-C to alpha-interferon treatment.

METHODS

HGV/GBV-C was detected and quantified by nested polymerase chain reaction. The influence of variables such as liver biopsy appearance, liver function abnormalities, and response of HCV to interferon treatment was monitored.

RESULTS

Fourteen of the 25 HGV/GBV-C-infected patients treated with interferon (3-6 MIU three times a week for 6 months) became non-viraemic during treatment, although all relapsed after treatment withdrawal at 6 months, with no net change in virus load between 0 and 12 months.

CONCLUSIONS

Predictive factors for clearance of HGV/GBV-C viraemia by interferon were pre-treatment severity of liver disease (median Knodell score of 4, compared with 7 for non-responders; P = 0.030) and alanine aminotransferase levels (median, 114, 182 for non-responders; P = 0.039). Clearance was associated with the treatment response of HCV. Nine of 13 who cleared HGV/GBV-C also cleared HCV, compared with 3 of 11 HGV/GBV-C non-responders; P = 0.05). The shared susceptibility of HGV/GBV-C and HCV to interferon treatment suggests a link between the mechanism of clearance of the two viruses.