The World Rugby and International Rugby Players Contact Load Guidelines: From conception to implementation and the future

Managing training load in rugby union is crucial for optimising performance and injury prevention. Contact training warrants attention because of higher overall injury and head impact risk, yet players must develop physical, technical, and mental skills to withstand the demands of the game. To help coaches manage contact loads in professional rugby, World Rugby and International Rugby Players convened an expert working group. They conducted a global survey with players to develop contact load guidelines. This commentary aims to describe the contact load guidelines and their implementation, and identify areas where future work is needed to support their evolution.

The silver bullet that wasn't: Rapid agronomic weed adaptations to glyphosate in North America

The rapid adoption of glyphosate-resistant crops at the end of the 20th century caused a simplification of weed management that relied heavily on glyphosate for weed control. However, the effectiveness of glyphosate has diminished. A greater understanding of trends related to glyphosate use will shed new light on weed adaptation to a product that transformed global agriculture. Objectives were to (1) quantify the change in weed control efficacy from postemergence (POST) glyphosate use on troublesome weeds in corn and soybean and (2) determine the extent to which glyphosate preceded by a preemergence (PRE) improved the efficacy and consistency of weed control compared to glyphosate alone. Herbicide evaluation trials from 24 institutions across the United States of America and Canada from 1996 to 2021 were compiled into a single database. Two subsets were created; one with glyphosate applied POST, and the other with a PRE herbicide followed by glyphosate applied POST. Within each subset, mean and variance of control ratings for seven problem weed species were regressed over time for nine US states and one Canadian province. Mean control with POST glyphosate alone decreased over time while variability in control increased. Glyphosate preceded by a labeled PRE herbicide showed little change in mean control or variability in control over time. These results illustrate the rapid adaptation of agronomically important weed species to the paradigm-shifting product glyphosate. Including more diversity in weed management systems is essential to slowing weed adaptation and prolonging the usefulness of existing and future technologies.

How COVID-19 impacted people with disabilities: A qualitative study in Delaware

Objectives

The COVID-19 pandemic created unprecedented challenges for people with disabilities and their caregivers and service providers. An assessment of how the COVID-19 pandemic, and the public health response to it, inequitably impacted the health and well-being of people with disabilities is needed to improve preparedness for future public health emergencies. Interviews were conducted with the goal of documenting the impacts of COVID-19 on community-dwelling individuals in Delaware.

Study design

Qualitative interviews using a structured interview guide.

Methods

In November and December 2022, interviews were conducted with individuals with disabilities, their caregivers, governmental and non-profit service providers, and elected representatives in Delaware. Interviews focused on obtaining information related to COVID-related threats to maintaining good health, affordable and accessible housing, work, educational opportunities, transportation, and community belonging during the pandemic. Interview transcripts were inductively analyzed.

Results

Five themes were identified including changes to, or loss of, home-based medical and other services, changes in daily routines that impacted access to work and education, limits on access to transportation, financial strains and housing issues, and mental health concerns.

Conclusions

The COVID-19 pandemic impacted nearly all aspects of the lives of people with disabilities. COVID-19 presented long-term, existential threats to progress made toward independent living, meaningful work, and financial, health, and educational equity for people with disabilities.

Timing and safety of hip fracture surgery in patients on direct-acting oral anticoagulants

Background

Many geriatric patients presenting for emergency hip fracture surgery are on direct oral anticoagulants (DOACs) most of which are not easily reversible. A safe policy was required to reduce delays to surgery. Prior to institution of our hospital's protocol in January 2021, most of these patients had surgery after 48 h following the last dose of DOAC due to concerns about increased perioperative blood loss.

Methods

This was a prospective closed loop audit of the protocol-surgery within 24 h from last dose of DOAC (if creatinine clearance >50 ml/min) with administration of 1-g of tranexamic acid at anesthesia induction. 131 eligible patients (DOAC, n = 22; no anticoagulation, n = 109) between January-June 2021 who had emergency hip fracture surgery were identified. Primary outcome measures were peri-operative blood loss, transfusion requirements and policy compliance. Secondary outcome measures were 30-day mortality, thrombotic complications and wound bleeding.

Results

Compliance with surgical timing and tranexamic acid administration were 55% and 81% respectively after the second audit cycle. The mean estimated blood loss (EBL) in the DOAC group versus the non-anticoagulated control group was 500 ml and 330 ml respectively. The difference between these groups was statistically significant at an alpha level of 5% (P = 0.0115, 95% CI 38.48-299.16). The difference for intra-operative (RR 3.43; 95% CI 1.68-7.01) and post-operative blood transfusion (RR 2.10; 95% CI 1.23-3.58) for the 2 groups was also statistically significant. However, there was no case of massive blood transfusion in both groups. The DOAC group had a lower risk for 30-day mortality (RR 0.71; 95% CI 0.09-5.46). There was no major thrombotic complication in the DOAC group.

Conclusion

This audit has shown that this protocol is safe although clinicians should anticipate some degree of increased intra-operative blood loss. We will recommend continuation of this policy with sustained safety monitoring in order to reduce delays to surgery.

Accelerated Solvent Extraction of Fluometuron from Selected Soils

Accelerated solvent extraction (ASE) is a recently developed extraction technique that is more rapid and produces less waste than do conventional liquid/liquid extraction methods. Optimal conditions were determined for ASE of fluometuron from 2 Weswood clay loam soils. Two solvents (acetonitrile and methanol), 2 temperatures (50 and 100C), and the number of static cycles (1, 2, and 3) were evaluated. The most efficient and reproducible extractions were obtained when methanol was combined with a 50C extraction temperature and the static cycle was repeated 3 times. These experiments indicated that existing extraction methods for fluometuron can easily be adapted for ASE.

Quasi One-Dimensional Metal-Semiconductor Heterostructures

The band offsets occurring at the abrupt heterointerfaces of suitable material combinations offer a powerful design tool for high performance or even new kinds of devices. Because of a large variety of applications for metal-semiconductor heterostructures and the promise of low-dimensional systems to present exceptional device characteristics, nanowire heterostructures gained particular interest over the past decade. However, compared to those achieved by mature two-dimensional processing techniques, quasi one-dimensional (1D) heterostructures often suffer from low interface and crystalline quality. For the GaAs-Au system, we demonstrate exemplarily a new approach to generate epitaxial and single crystalline metal-semiconductor nanowire heterostructures with atomically sharp interfaces using standard semiconductor processing techniques. Spatially resolved Raman measurements exclude any significant strain at the lattice mismatched metal-semiconductor heterojunction. On the basis of experimental results and simulation work, a novel self-assembled mechanism is demonstrated which yields one-step reconfiguration of a semiconductor-metal core-shell nanowire to a quasi 1D axially stacked heterostructure via flash lamp annealing. Transmission electron microscopy imaging and electrical characterization confirm the high interface quality resulting in the lowest Schottky barrier for the GaAs-Au system reported to date. Without limiting the generality, this novel approach will open up new opportunities in the syntheses of other metal-semiconductor nanowire heterostructures and thus facilitate the research of high-quality interfaces in metal-semiconductor nanocontacts.

Modelling Local and Small-Area Income Distributions in Scotland

Reliable local income data remains a key missing element within British official statistics. The authors discuss the development of a model of local income distributions intended to overcome this problem, particularly in the context of housing-affordability analysis. The model links national surveys (the Family Expenditure Survey and Scottish House Condition Survey) to local data available from census and other sources. Developments to the model are described including: tenure disaggregation, calibration and testing with the aid of micro and other datasets; application down to small-area (postcode-sector) level; updating and projection from census to recent and future dates; and predicting benefit take-up. Discussion of the results highlights some features of recent income patterns and trends in Scotland as well as the value and limitations of the method.

A Review of the Behaviour Assessment System for Children

This article is a review of the Behaviour Assessment System for Children (BASC), a broadband assessment tool, which is of potential interest to psychologists practicing within education, clinical/counselling and research settings. Designed to measure the behaviours and self perceptions of children from two and a half to 18 years, across both maladaptive and adaptive behaviour, the BASC has several features which makes it the test of choice in particular clinical and research situations. Each of the five main BASC components, including the Structured Developmental History, Parent Rating Scale, Teacher Rating Scale, Self Report of Personality and Student Observation System, is described and evaluated with reference made to the strengths and limitations of each. Where relevant, comparisons are drawn with the Child Behaviour Checklist and Teacher Report Form, and much of the research utilizing the BASC to date is summarized. Information regarding the test's psychometric properties, test development, administration and scoring is also presented. Overall, it seems that the BASC is a comprehensive and psychometrically sound assessment tool with much to offer psychologists working with children and adolescents.

Proximity of the axillary nerve during bicortical drilling for biceps tenodesis

PURPOSE

Pathology of the biceps tendon can contribute to significant shoulder pain and dysfunction for which biceps tenodesis may be indicated. A variety of techniques tenodesing the biceps tendon have been described. Recently, tenodesis using a uni- or bicortical button has been advocated. This cadaveric study investigates the proximity of the axillary nerve to the position of bicortical drill passages during biceps tenodesis.

METHODS

Twelve cadaveric shoulder specimens were used. The axillary nerve was marked during a preparatory dissection using wire. Drills were passed through the humerus at the proximal and distal ends of the bicipital groove, and at the superior insertion point of pectoralis major (PM). These were left in situ. The distances between these drills and the axillary nerves were measured using computed tomography imaging.

RESULTS

The drill bits placed at the superior insertion of PM were in closest proximity to the axillary nerve (3D distance mean 10.7 mm, 95 % confidence interval 7.2-14.2 mm). A drill placed at the distal end of the bicipital groove was a mean distance of 18.2 mm from the nerve.

CONCLUSIONS

This study highlights the need for caution when drilling the posterior humeral cortex during biceps tenodesis, particularly during drilling at the superior insertion of PM as this is the location that poses the highest risk to the axillary nerve. To our knowledge, this is the first cadaveric study to radiologically assess the proximity of the axillary nerve to the positions of biceps tenodesis. Surgeons should therefore be cautious when performing bicortical drilling for biceps tenodesis, and a supero-lateral drill trajectory would pose a smaller risk to the axillary nerve.

Nucleation of Ga droplets on Si and SiOx surfaces

We report on gallium droplet nucleation on silicon (100) substrates with and without the presence of the native oxide. The gallium deposition is carried out under ultra-high vacuum conditions at temperatures between 580 and 630 °C. The total droplet volume, obtained from a fit to the diameter-density relation, is used for sample analysis on clean silicon surfaces. Through a variation of the 2D equivalent Ga thickness, the droplet diameter was found to be between 250-1000 nm. Longer annealing times resulted in a decrease of the total droplet volume. Substrate temperatures of 630 °C and above led to Ga etching into the Si substrates and caused Si precipitation around the droplets. In contrast, we obtained an almost constant diameter distribution around 75 nm over a density range of more than two orders of magnitude in the presence of a native oxide layer. Furthermore, the droplet nucleation was found to correlate with the density of surface features on the 'epi-ready' wafer.

Chance fracture of the talus and calcaneum

Combined talus and calcaneum fractures are rare in themselves. We report the case of an unusual fracture pattern of the talus and calcaneum in an otherwise, healthy 17-year-old male. Plain radiographic images of the foot revealed a fracture through the neck of the talus. Additional computed tomography imaging showed the fracture line extending through the talus and entire calcaneum. The fracture was open and associated with rupture of the tibialis anterior and extensor hallucis longus tendons. The patient underwent debridement with open reduction and internal fixation of the talar component of the fracture using 2 screws. The calcaneal component was treated conservatively. The soft tissue injuries to the 2 tendons were also repaired. The patient made good progress with this management.

and my World:” Perceptions of County Educators and Volunteers toward International 4-H Programs

The phrase “…and my world” was added to the 4-H pledge in 1973, forever solidifying 4-H’s commitment to international programming and global citizenship. In 2008, Oklahoma 4-H began to consider revitalizing its international outreach. After researching the barriers to International 4-H projects, Oklahoma 4-H educators and volunteers were surveyed to discover their interests in this area with the intent of beginning a renewed International 4-H program with educator and volunteer support. The survey results indicate that 4-H volunteers and youth educators prefer short term International educational programs that focus on cultural awareness and service-learning for older youth.

Phase II study of biweekly cetuximab (C) and irinotecan (I) as a second-line regimen for metastatic colorectal cancer (mCRC)

e15088

Background: I + C is a standard second line mCRC regimen. Our study investigated the efficacy and safety of a biweekly I + C combination in patients (pts) with mCRC. Methods: mCRC pts who failed 1st line fluoropyrimidine/oxaliplatin regimens and had not received I or C, were eligible for this open label phase II trial with response rate (RR) as the primary end-point and planned sample size of 31 patients to achieve a 25% RR with 80% power. C 500 mg/m2 IV was administered on d1 followed by I 180 mg/m2 IV over 60 minutes biweekly. Results: Pt. characteristics (n=32): Male (n=17), female (n=15), Median age 59.9; ECOG PS ≤1 (31 pt), PS=2 (1). Median number of cycles 3 (range 1–21), 17pts received ≤ 3 cycles. Chemotherapy doses were reduced/delayed in 20 pts. Initial I dose was reduced to 150mg/m2 in 12 pts due to previous radiation (6 pts), age ≥ 70 years (5 pts), or PS 2 (1 pt). Grade 3 or 4 adverse events: acneiform rash (n=6), diarrhea (n=5), and neutropenia (n=4); possible grade 5 (respiratory failure). One PR was seen, 12 pts had stable and 13 pts PD; 6 pts were not evaluable for response. Median OS 11.1 mos (95% CI 6.0–15.1) and TTP 2.4 mos (95% CI 1.4-NA). Among the 23 pts tested, 9 pts had KRAS, and 2 pts BRAF mutations. There was a trend towards higher OS and TTP among pts with wild type (wt) KRAS (OS 11.9 vs 9.96mo, p=0.66; TTP 5.97 vs 3.11mo, p=0.288) and BRAF (OS 12 vs 4.6mo, p=0.17; TTP 4.56 vs 1.86mo, p=0.239). Conclusions: The lower RR than previously reported was likely caused by the small sample size and possibly those factors leading to initial I dose reductions. In addition 90% of patients had prior therapy with FOLFOX/bevacizumab. The OS and TTP are consistent with those reported previously (Martin et al Brit J Cancer 2008, Pfeiffer P et al Ann Oncol 2008), supporting biweekly I + C as a convenient second-line regimen in mCRC.

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Accelerated solvent extraction of fluometuron from selected soils

Accelerated solvent extraction (ASE) is a recently developed extraction technique that is more rapid and produces less waste than do conventional liquid/liquid extraction methods. Optimal conditions were determined for ASE of fluometuron from 2 Weswood clay loam soils. Two solvents (acetonitrile and methanol), 2 temperatures (50 and 100 degrees C), and the number of static cycles (1, 2, and 3) were evaluated. The most efficient and reproducible extractions were obtained when methanol was combined with a 50 degrees C extraction temperature and the static cycle was repeated 3 times. These experiments indicated that existing extraction methods for fluometuron can easily be adapted for ASE.

Predictors of depression in female adolescents

Depression during adolescence has been associated with a number of factors, including failure to individuate (Blos, 1968), insecure attachments (Armsden, McCauley, Greenberg, Burke, & Mitchell, 1990), negative parental representations, and object relations that lack self-other differentiation (Blatt, Wein, Chevron, & Quinlan, 1979). The present study examined factors associated with symptoms of depression in 59 nonclinical female adolescents. Specifically, the relationship between a number of theoretically related measures-separation-individuation, interpersonal concerns, self-critical concerns, attachment style, parental representations-and symptoms of depression was investigated. The model developed was able to explain the interrelationships of the variables involved in the psychological process of adolescence, and their demonstrated ability to predict symptoms of depression in normal female adolescents.

Baseline factors predicting early resumption of driving after life-threatening arrhythmias in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Trial

BACKGROUND

In the Antiarrhythmics Versus Implantable Defibrillators (AVID) Trial, patients with ventricular fibrillation or hemodynamically unstable ventricular tachycardia were randomly assigned to receive either an implantable cardioverter-defibrillator (ICD) or antiarrhythmic drug therapy. As part of the trial, patients were asked to participate in a prospective driving survey. The purpose of the survey was to determine what baseline factors and patient characteristics specifically predicted resumption of driving earlier than advised by current guidelines.

METHODS

Patients were surveyed anonymously as to their driving habits in the initial period after random assignment and every 6 months thereafter. AVID study coordinators were independently asked to assess their patients' driving status as well. The relation between baseline factors and time to resumption of driving was explored by means of Kaplan-Meier estimates for univariate analyses and the stepwise Cox proportional hazards regression model for multivariate analyses.

RESULTS

There were 802 patients who were eligible for assessment of driving status. The majority of patients (58%) resumed driving an automobile within 6 months of their index arrhythmia regardless of whether they received drug therapy or an ICD. By multivariate analysis, patients who were younger than 65 years of age, male, and college educated were more likely to drive early, as were patients whose index arrhythmia was ventricular tachycardia.

CONCLUSIONS

Younger, college-educated men and those whose index arrhythmia is ventricular tachycardia are most likely to resume driving <6 months after the initiation of therapy for a potentially life-threatening ventricular arrhythmia. Patients with an ICD did not appear to resume driving later than those who were discharged on antiarrhythmic drugs alone.

Electrical storm presages nonsudden death: the antiarrhythmics versus implantable defibrillators (AVID) trial

BACKGROUND

Electrical storm, multiple temporally related episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF), is a frequent problem among recipients of implantable cardioverter defibrillators (ICDs). However, insufficient data exist regarding its prognostic significance.

METHODS AND RESULTS

This analysis includes 457 patients who received an ICD in the Antiarrhythmics Versus Implantable Defibrillators (AVID) trial and who were followed for 31 +/- 13 months. Electrical storm was defined as > or = 3 separate episodes of VT/VF within 24 hours. Characteristics and survival of patients surviving electrical storm (n = 90), those with VT/VF unrelated to electrical storm (n = 184), and the remaining patients (n = 183) were compared. The 3 groups differed in terms of ejection fraction, index arrhythmia, revascularization status, and baseline medication use. Survival was evaluated using time-dependent Cox modeling. Electrical storm occurred 9.2 +/- 11.5 months after ICD implantation, and most episodes (86%) were due to VT. Electrical storm was a significant risk factor for subsequent death, independent of ejection fraction and other prognostic variables (relative risk [RR], 2.4; 95% confidence interval [CI], 1.3 to 4.2; P = 0.003), but VT/VF unrelated to electrical storm was not (RR, 1.0; 95% CI, 0.6 to 1.7; P = 0.9). The risk of death was greatest 3 months after electrical storm (RR, 5.4; 95% Cl, 2.4 to 12.3; P = 0.0001) and diminished beyond this time (RR, 1.9; 95% CI, 1.0 to 3.6; P=0.04).

CONCLUSIONS

Electrical storm is an important, independent marker for subsequent death among ICD recipients, particularly in the first 3 months after its occurrence. However, the development of VT/VF unrelated to electrical storm does not seem to be associated with an increased risk of subsequent death.

Determinants of outcome in patients with sustained ventricular tachyarrhythmias: the antiarrhythmics versus implantable defibrillators (AVID) study registry

BACKGROUND

The prognosis of patients with sustained ventricular tachyarrhythmias varies according to clinical characteristics. We sought to identify predictors of survival in a large population of patients with documented sustained ventricular tachyarrhythmias not related to reversible or correctable causes included in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Registry.

METHODS AND RESULTS

We analyzed the impact of 36 demographic, clinical, and discharge treatment variables on the outcome for 3559 patients. Survival status was assessed with the use of the National Death Index. Multivariate analyses were performed with the use of the Cox proportional hazards model. After a mean follow-up of 17 +/- 12 months, 631 patients died. Actuarial survival was 0.86 (95% confidence interval [CI] 0.85 to 0.88), 0.79 (95% CI 0.78 to 0.81), and 0.72 (95% CI 0.70 to 0.74) at 1, 2, and 3 years. Multivariate predictors of worse survival included older age, severe left ventricular dysfunction, lower systolic blood pressure, history of congestive heart failure, diabetes, smoking or atrial fibrillation, and preexistent pacemaker. The hemodynamic impact of the qualifying arrhythmia was not a predictor of outcome. Defibrillator implantation and hospital discharge while the patient was taking a beta-blocker or an angiotensin-converting enzyme inhibitor were associated with better prognosis.

CONCLUSIONS

Despite therapeutic advances, the mortality rates of patients with sustained ventricular tachyarrhythmias remain high. Prognosis depends on the severity of underlying heart disease, as reflected by the extent of left ventricular dysfunction and the presence of heart failure. Well-tolerated ventricular tachycardia in patients with structural heart disease does not carry a significantly better prognosis than ventricular tachyarrhythmia with more severe hemodynamic consequences.

A comparison of the efficacy and tolerability of two recombinant human follicle-stimulating hormone preparations in patients undergoing in vitro fertilization-embryo transfer

OBJECTIVE

To compare the efficacy and tolerability of two recombinant human FSH (r-hFSH) preparations, follitropin-alpha (Gonal-F; Ares Serono, Geneva, Switzerland) and follitropin-beta (Puregon; Organon, Oss, the Netherlands), for superovulation in patients undergoing IVF-ET.

DESIGN

Randomized, parallel-group, assessor-blind, single-center trial.

SETTING

Outpatient tertiary referral center for assisted reproductive techniques.

PATIENT(S)

Forty-four infertile women undergoing IVF-ET.

INTERVENTION(S)

After down-regulation with buserelin acetate, patients were randomized to receive follitropin-alpha or follitropin-beta, 150 IU/d for 6 days; after that, dosages were adjusted according to the ovarian response.

MAIN OUTCOME MEASURE(S)

Cumulative dose of r-hFSH; duration of r-hFSH treatment; number of follicles of > or =11 mm and of 14 mm on day 7 of r-hFSH treatment and on the day of hCG administration; number of oocytes retrieved; number of viable embryos; and number of pregnancies (biochemical, ectopic, miscarried) and clinical pregnancies.

RESULT(S)

There were no statistically significant differences in any efficacy measures between the two preparations. The incidence of systemic adverse events was comparable in the two groups. Local reactions at the injection site were significantly more common and more severe with follitropin-beta than with follitropin-alpha

CONCLUSION(S)

Follitropin-alpha and follitropin-beta have comparable efficacy in patients undergoing IVF-ET.

Relative effectiveness of the implantable cardioverter-defibrillator and antiarrhythmic drugs in patients with varying degrees of left ventricular dysfunction who have survived malignant ventricular arrhythmias. AVID Investigators. Antiarrhythmics Versus Implantable Defibrillators

OBJECTIVES

We sought to assess the effect of baseline ejection fraction on survival difference between patients with life-threatening ventricular arrhythmias who were treated with an antiarrhythmic drug (AAD) or implantable cardioverter-defibrillator (ICD).

BACKGROUND

The Antiarrhythmics Versus Implantable Defibrillators (AVID) study demonstrated improved survival in patients with ventricular fibrillation or ventricular tachycardia with a left ventricular ejection fraction (LVEF) < or =0.40 or hemodynamic compromise.

METHODS

Survival differences between AAD-treated and ICD-treated patients entered into the AVID study (patients presenting with sustained ventricular arrhythmia associated with an LVEF < or =0.40 or hemodynamic compromise) were compared at different levels of ejection fraction.

RESULTS

In patients with an LVEF > or =0.35, there was no difference in survival between AAD-treated and ICD-treated patients. A test for interaction was not significant, but had low power to detect an interaction. For patients with an LVEF 0.20 to 0.34, there was a significantly improved survival with ICD as compared with AAD therapy. In the smaller subgroup with an LVEF <0.20, the same magnitude of survival difference was seen as that in the 0.20 to 0.34 LVEF subgroup, but the difference did not reach statistical significance.

CONCLUSIONS

These data suggest that patients with relatively well-preserved LVEF (> or =0.35) may not have better survival when treated with the ICD as compared with AADs. At a lower LVEF, the ICD appears to offer improved survival as compared with AADs. Prospective studies with larger patient numbers are needed to assess the effect of relatively well-preserved ejection fraction (> or =0.35) on the relative treatment effect of AADs and the ICDs.

In-hospital versus out-of-hospital presentation of life-threatening ventricular arrhythmias predicts survival: results from the AVID Registry. Antiarrhythmics Versus Implantable Defibrillators

OBJECTIVES

This study describes the outcomes of patients from the Antiarrhythmics Versus Implantable Defibrillators (AVID) Study Registry to determine how the location of ventricular arrhythmia presentation influences survival.

BACKGROUND

Most studies of cardiac arrest report outcome following out-of-hospital resuscitation. In contrast, there are minimal data on long-term outcome following in-hospital cardiac arrest.

METHODS

The AVID Study was a multicenter, randomized comparison of drug and defibrillator strategies to treat life-threatening ventricular arrhythmias. A Registry was maintained of all patients with sustained ventricular arrhythmias at each study site. The present study includes patients who had AVID-eligible arrhythmias, both randomized and not randomized. Patients with in-hospital and out-of-hospital presentations are compared. Data on long-term mortality were obtained through the National Death Index.

RESULTS

The unadjusted mortality rates at one- and two-year follow-ups were 23% and 31.1% for patients with in-hospital presentations, and 10.5% and 16.8% for those with out-of-hospital presentations (p < 0.001), respectively. The adjusted mortality rates at one- and two-year follow-ups were 14.8% and 20.9% for patients with in-hospital presentations, and 8.4% and 14.1% for those with out-of-hospital presentations (p < 0.001), respectively. The adjusted long-term relative risk for in-hospital versus out-of-hospital presentation was 1.6 (95% confidence interval [CI] 1.3-1.9).

CONCLUSIONS

Compared with patients with out-of-hospital presentations of life-threatening ventricular arrhythmias not due to a reversible cause, patients with in-hospital presentations have a worse long-term prognosis. Because location of ventricular arrhythmia presentation is an independent predictor of long-term outcome, it should be considered as an element of risk stratification and when planning clinical trials.

Relation of circadian ventricular ectopic activity to cardiac mortality. CAST Investigators

The relation between the circadian occurrence of ventricular premature depolarizations (VPD) and sudden arrhythmic death was examined in a subset of patients entered into the Cardiac Arrhythmia Suppression Trial (CAST). Ambulatory electrocardiographic recordings with hourly measurement of VPD frequency were available in 357 patients. Forty percent of the patients (142 of 357) demonstrated circadian variation in VPD frequency between 6:00 A.M. and 9:59 A.M. that was significantly higher (p < 0.05) than what could randomly be expected from an overall 24-hour average for that patient. The only baseline characteristics in patients with circadian VPDs were age (p < 0.04), history of cardiac arrest (p < 0.01), presence of higher frequency of VPDs (p < 0.002), more frequent episodes of ventricular tachycardia (p < 0.04), and more frequent episodes of slow runs (p < 0.04). There was no difference in mortality in patients with or without circadian VPD variation; drug treatment did not effect mortality. These data indicate that the presence of circadian VPDs is not a predictor of sudden arrhythmic death in patients with a high frequency of VPDs.

A further presenilin 1 mutation in the exon 8 cluster in familial Alzheimer's disease

Recent studies suggest that mutations in the presenilin 1 gene, which encodes a polypeptide predicted to be a multispanning membrane protein, are responsible for the majority of cases of early onset, autosomal dominant Alzheimer's disease. Here we describe a further mutation in the presenilin 1 gene (R269G) in a family with early onset Alzheimer's disease. This mutation is in exon 8 which appears to be a favoured region for pathogenic mutations. In the presenilin protein the region coded for by this exon is likely to comprise a domain located on the membrane surface. We discuss the likely effects of the exon 8 mutations on the structure of the exon and in the pathogenesis of the disease.

Clinical trial enrollers vs. nonenrollers: the Cardiac Arrhythmia Suppression Trial (CAST) Recruitment and Enrollment Assessment in Clinical Trials (REACT) project

The Recruitment and Enrollment Assessment in Clinical Trials (REACT) was a National Heart, Lung, and Blood Institute (NHLBI)-sponsored substudy to the Cardiac Arrhythmia Suppression Trial (CAST). Two-hundred-sixty (260) patients who enrolled in CAST and 140 partially or fully eligible patients who did not enroll were compared across several parameters, including demographic variables, disease severity, psychosocial functioning, health beliefs, recruitment experience, and understanding of informed consent procedures used in CAST. Significant predictors of enrollment included several demographic variables (e.g., being male, not having medical insurance), episodes of ventricular tachycardia, and health beliefs (e.g., extra beats are harmful, a higher degree of general health concern). Enrollment was higher for those who read and understood the informed consent and those who were initially recruited after hospital discharge, particularly nondepressed patients. In the multivariate model, the key variables that emerged were the patient's reading of the informed consent form and the patient's lack of medical insurance. These results suggest that (1) the clinical trial staff's interaction with the patient and the time when recruitment is initiated contribute significantly to the decision to enroll; and (2) it may be a greater challenge to motivate patients to enroll in future clinical trials if health care reform improves access to medical insurance coverage. Some of the significant variables are modifiable, suggesting interventions that may increase enrollment rates in future trials.

Beneficial effects of androgen-primed chemotherapy in the Dunning R3327 G model of prostatic cancer

The objective of this study was to test the hypothesis that androgen administration prior to chemotherapy (androgen priming) may potentiate tumor cytotoxicity in hormone-responsive prostate cancer. Accordingly, six groups of Copenhagen rats bearing small (i.e., 40-mm3 median volume) Dunning R3327 G tumors were left untreated or received castration, chemotherapy, or a combination of the two, with or without androgen priming. Groups without priming included: intact untreated, castrate alone, intact plus chemotherapy, and castrate plus chemotherapy (cyclophosphamide, 30 mg/kg/day, for 2 days, with repeat cycle in 24 days) (Cx). To specifically evaluate the effect of androgen priming on Cx cytotoxicity, two additional castrate groups were studied. One received testosterone propionate (4 mg/kg/day) for 2 days prior to Cx and the other after Cx. Treatment effect was evaluated by quantitating tumor volume as well as animal survival to an ethically allowable, maximal tumor burden. As expected, castration and Cx produced a retardation of tumor growth and prolongation of survival when compared to untreated animals. The addition of androgen priming prior to but not after Cx enhanced the degree of tumor suppression. Specifically, 26 days after the second Cx cycle, all androgen-primed tumors had regressed; 70% of tumors had disappeared and those remaining were barely palpable. At this same time point, tumors in all the other groups were actively growing and had volumes greater than initial values (P less than 0.01). Although tumor regrowth occurred, median survival for the androgen-primed group was significantly prolonged, to 186 days versus 39 days (P less than 0.01) for untreated animals and 153 days for the non-primed castrate plus Cx animals (P less than 0.01). These data suggested that androgen priming potentiates the effects of Cx in castrate animals bearing R3327 G tumors.

Kinetic and morphometric responses of heterogeneous populations of NMU-induced rat mammary tumor cells to hormone and antipolyamine therapy in vivo

The present experiments were designed to evaluate in vivo the differential sensitivity of tumor cell subpopulations to hormone and polyamine manipulations using the hormone-responsive N-nitrosomethyl-urea (NMU)-induced rat mammary tumor. NMU tumor bearing rats were randomly assigned to control, ovariectomy, alpha-difluoromethyl-ornithine (DFMO) administration (an inhibitor of polyamine biosynthesis), or combination treatment, and were sacrificed on day 2, 4, or 7. The proportion of different cells was estimated by morphometric analysis and their replicative activities by [3H]-thymidine autoradiography. In tumors of intact rats, the fractions of glandular, myoepithelial, and non-epithelial cells were 85.3 +/- 2.2%, 4.7 +/- 0.7%, and 9.9 +/- 1.9%, respectively. Ovariectomy induced a similar time-dependent decline in the labelling indices of each cell type (from 5% to 1%). It also decreased the fraction of glandular cells (74.9 +/- 4.5%), while increasing the fraction of myoepithelial (8.6 +/- 1.9%) and non-epithelial (16.3 +/- 3.2%) cells. DFMO exerted similar but more modest effects. DFMO-induced tumor regression was also inferior to that observed with ovariectomy. Combined ovariectomy and DFMO induced a faster and greater suppression of all labelling indices than the individual treatments, even though tumor regression was not superior to that produced by ovariectomy alone. Combination treatment also produced more profound morphologic changes, reducing the fraction of glandular cells to 64.4 +/- 3.9% and increasing that of non-epithelial cells to 26.6 +/- 4.4%. Ovariectomy and DFMO reduced height but not width of glandular cells, resulting in a modest decrease in cell volume. The combination treatment, however, significantly suppressed all three parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

A surface polysaccharide forms when gonococci are converted to serum resistance by cytidine 5'-monophospho-N-acetyl neuraminic acid

A serum-susceptible, guinea-pig chamber-passaged, laboratory strain (BS4 (agar)) of Neisseria gonorrhoeae was converted to serum resistance by incubation with cytidine 5-monophospho-N-acetyl neuraminic acid (CMP-NANA) and examined by electron microscopy after staining with ruthenium-red. In contrast to serum susceptible gonococci incubated without CMP-NANA, the majority (60-70%) of the serum resistant organisms showed a surface accumulation of polysaccharide. This surface polysaccharide was enhanced on all the resistant gonococci after incubation with fresh human serum. Control susceptible gonococci were devoid of the polysaccharide after incubation with heated human serum. Identical results were obtained with a fresh gonococcal isolate which had lost serum resistance on subculture but which, in common with 3 other isolates, was restored to serum resistance by incubation with CMP-NANA.

Child behavior ratings: the influence of maternal characteristics and child temperament

This study investigated the extent to which maternal characteristics, such as psychological health problems, marital adjustment and confidence in mother/wife roles, influenced how mothers rated the behavior of their first-born children (n = 100) on the Pre-school Behavior Questionnaire. Results showed that these characteristics were powerful predictors of behavior ratings. In contrast, the independent contribution of child temperament ratings was relatively small. It was concluded that child behavior problem and temperament measures may be confounded. Maternal ratings constitute a valuable source of information concerning parent-child interaction which deserve further investigation, especially of their influence on generally accepted measures of child behavioral adjustment.

Kinetic and morphometric responses of heterogeneous populations of experimental breast cancer cells in vivo

Although the hormone responsiveness of some breast cancers is well known, the differential sensitivity of tumor cell subpopulations to hormonal effects is not well established. These experiments were designed to address this issue using the hormone-responsive N-nitrosomethylurea-induced rat mammary tumor. Rats bearing these tumors were randomly assigned to no treatment, 7-day castration, and 7-day castration followed by 1-, 3-, 7-, and 10-day treatment with estradiol benzoate (5 micrograms) and perphenazine (1 mg) to stimulate prolactin release. Under these conditions, the proportion of different cell populations was estimated with morphometric analysis, while their replicative activity was assessed using [3H]thymidine autoradiography. In tumors of intact rats the fractions of glandular epithelial, myoepithelial, and nonepithelial cells were 88.2%, 3.8%, and 8.0%, respectively. All cell types manifested a similar kinetic response to our hormonal treatments characterized by a drastic decline in the labeling index after castration followed by a progressive increase with hormone repletion which peaked on Day 7 of treatment. The magnitude of the response was, however, greater in the epithelial components of the tumor (glandular and myoepithelial cells), where the peak labeling indices significantly exceeded those observed in the tumors of control intact rats. Castration reduced the proportion of glandular cells while increasing the fractions of myoepithelial and nonepithelial cells. Furthermore, castration reduced the volume of the glandular-epithelial cells by 35%, which accounted for approximately half of the overall tumor volume reduction induced by ovariectomy. These alterations in tumor morphology were partially reversed by hormone repletion. These results underscore the exquisite hormonal sensitivity of different cellular counterparts of this experimental breast cancer with regard to both kinetic and morphological characteristics. They also provide support for stromal-epithelial interaction in the hormonal modulation of breast cancer growth.

Complete acromioclavicular separations. A comparison of operative methods

A retrospective study of the surgical treatment methods for complete acromioclavicular (AC) dislocations was initiated to investigate the efficacy of each. During the years 1972-1985, a total of 95 surgical procedures were performed for complete AC dislocations. The medical records of 90 cases were available for review. The operative methods compared coracoclavicular (CC) with AC fixation methods. Excision of the distal clavicle was performed for chronic dislocations. AC fixation methods included Kirschner wires alone, Kirschner-wire fixation with coracoacromial ligament transfer, and Kirschner-wire fixation with tension wiring. Results were graded using evaluation of pain, range of motion, and residual deformity. AC fixation methods proved to be more successful than CC fixation methods. Excellent results were obtained in more than 89% of both AC and CC methods. AC methods had more minor complications including infections and implant breakage, but no failure or recurrences of the dislocation. CC methods resulted in 9% failure or recurrences. Of the AC fixation methods, the Kirschner wire with tension wiring gave the best results but required a more extensive operation for removal of implants. Excision of the distal end of the clavicle is an adequate form of treatment for the chronic complete painful AC dislocation.

Lateral idiopathic subluxation of the radial head. Case report

Idiopathic subluxation of the radial head (ISRH) is a rare entity that is separate from congenital dislocations of the radial head, both symptomatically and radiographically. ISRH causes pain and restriction of rotation. A dome-shaped radial head, a hypertrophied ulna, and a hypoplastic capitellum are not present in ISRH, as they are in a congenital dislocation of the radial head (CDRH). A true lateral ISRH is used as an example to demonstrate these differences. Remodeling of the radial head may preserve motion in the joint surface deformed by growth along abnormal planes of motion.

Subtalar dislocations: a prognosticating classification

A review of the literature and analysis of eight cases of subtalar dislocations was undertaken to correlate our experience with others and to determine a classification for prognostication. Our findings corresponded with those found by others. A 75% incidence of associated injuries was present in our series and these represented a continuum of varying degrees of complication. A new system was devised whereby increasing severity of associated injuries correlated with increasing rate of complications, including loss of motion, arthritis, pain and avascular necrosis. Dislocations were classified according to: no associated injuries, those with soft tissue injuries, extra-articular fractures, intra-articular fractures and those prone to development of avascular necrosis, ie, open dislocations and fractures of the body of the talus. It was found that associated fractures increased the immobilization period as well as the incidence of complications. Intra-articular fractures have demonstrated increased rates of arthroses in the subtalar joint. Avascular necrosis, an infrequent but devastating complication, is primarily associated with open dislocations and dislocations with concomitant fractures of the body of the talus. Our series had two open subtalar dislocations, neither of which developed avascular necrosis.