Predictors of Symptom Outcome in Interpretation Bias Modification for Dysphoria

Interpretation Bias Modification (IBM) interventions have been effective in reducing negative interpretation biases theorized to underlie depressive psychopathology. Although these programs have been highlighted as potential short-term interventions for depression, mixed evidence has been found for their effects on depressive symptoms. There is a need to examine attitudes towards training as well as individual difference factors that may impact symptom outcomes for IBM depression interventions. Seventy-two dysphoric young adults were randomly assigned to receive either an IBM targeting negative interpretation bias in personal evaluations or interpersonal situations or a healthy video control (HVC) condition. Compared to those who received HVC, participants in the IBM condition reported lower negative interpretation bias at posttreatment. No differences between conditions were found for symptom outcomes. Greater perceived treatment credibility and expectancy were associated with better treatment outcomes for both the IBM and HVC groups. Within the IBM group, a greater tendency toward assimilation with treatment scenarios was significantly associated with better treatment outcomes for both depressive and anger symptoms. This effect was unique from treatment credibility and expectancy. Pretreatment psychological reactance did not predict treatment response for either condition. Implications and future research directions are discussed.

Event-based processing of neutron scattering data at the Spallation Neutron Source

The Spallation Neutron Source at Oak Ridge National Laboratory, USA, ushered in a new era of neutron scattering experiments through the use of event-based data. Tagging each neutron event allows pump–probe experiments, measurements with a parameter asynchronous to the source, measurements with continuously varying parameters and novel ways of testing instrument components. This contribution will focus on a few examples. A pulsed magnet has been used to study diffraction under extreme fields. Continuous ramping of temperature is becoming standard on the POWGEN diffractometer. Battery degradation and phase transformations under heat and stress are often studied on the VULCAN diffractometer. Supercooled Al2O3 was studied on NOMAD. A study of a metallic glass through its glass transition was performed on the ARCS spectrometer, and the effect of source variation on chopper stability was studied for the SEQUOIA spectrometer. Besides a summary of these examples, an overview is provided of the hardware and software advances to enable these and many other event-based measurements.

Long term use of hydraulic artificial urethral sphincters in nine dogs from New Zealand with urethral sphincter mechanism incompetence

AIMS

To report on the long-term outcomes of hydraulic artificial urethral sphincter (HAUS) placement for the correction of urethral sphincter mechanism incompetence (USMI) in New Zealand dogs.

METHODS

Retrospective data were obtained from cases of dogs which had a HAUS placed after failed medical and/or surgical management of USMI between August 2012 and November 2016. Owner assessment of urinary incontinence was evaluated by an online survey in May 2017 using a visual analogue scale (0 being normal, 100 being severely affected) for the frequency, volume and severity of any straining to urinate, immediately prior to the placement of the HAUS and at the time of the survey. The number of days between surgery and the completion of survey were recorded.

RESULTS

Seven females and two male dogs, which were all desexed except for one female, were eligible for inclusion in the study. The period of follow-up following HAUS placement ranged from 206-1,685 days. Following HAUS placement, frequency and volume of urinary incontinence decreased for six dogs and were practically unchanged for three dogs. The median frequency score decreased from 70 to 13 and the volume score decreased from 73 to 12. There was no consistent change in the perceived degree of straining to urinate. Complications occurred in three dogs; one required repositioning of a dislodged injection port, one required management for haematuria and a hypoplastic bladder, and one required surgical removal of fibrous tissue around the HAUS cuff.

CONCLUSIONS AND CLINICAL RELEVENCE

HAUS placement was an effective method for the treatment of persistent USMI in most dogs and provided good clinical results based on owner assessment. The technique was associated with few complications and allowed successful long-term control of urinary incontinence without the need for medical management.

Nuclear quantum effect with pure anharmonicity and the anomalous thermal expansion of silicon

Despite the widespread use of silicon in modern technology, its peculiar thermal expansion is not well understood. Adapting harmonic phonons to the specific volume at temperature, the quasiharmonic approximation, has become accepted for simulating the thermal expansion, but has given ambiguous interpretations for microscopic mechanisms. To test atomistic mechanisms, we performed inelastic neutron scattering experiments from 100 K to 1,500 K on a single crystal of silicon to measure the changes in phonon frequencies. Our state-of-the-art ab initio calculations, which fully account for phonon anharmonicity and nuclear quantum effects, reproduced the measured shifts of individual phonons with temperature, whereas quasiharmonic shifts were mostly of the wrong sign. Surprisingly, the accepted quasiharmonic model was found to predict the thermal expansion owing to a large cancellation of contributions from individual phonons.

Design and operating characteristic of a vacuum furnace for time-of-flight inelastic neutron scattering measurements

We present the design and operating characteristics of a vacuum furnace used for inelastic neutron scattering experiments on a time-of-flight chopper spectrometer. The device is an actively water cooled radiant heating furnace capable of performing experiments up to 1873 K. Inelastic neutron scattering studies performed with this furnace include studies of phonon dynamics and metallic liquids. We describe the design, control, characterization, and limitations of the equipment. Further, we provide comparisons of the neutron performance of our device with commercially available options. Finally we consider upgrade paths to improve performance and reliability.

Hostile interpretation training for individuals with alcohol use disorder and elevated trait anger: A controlled trial of a web-based intervention

High trait anger is associated with more severe alcohol use problems, and alcohol has been found to facilitate aggressive behavior among individuals with high trait anger. Treatments focused on a sample with alcohol use disorder with elevated anger could reduce alcohol use problems, as well as violence and aggression. We sought to examine the efficacy of interpretation bias modification for hostility (IBM-H) in a sample with high trait anger and alcohol use disorder (AUD). Fifty-eight individuals with AUD and elevated trait anger were randomly assigned to eight web-based sessions (two per week) of IBM-H or a healthy video control condition (HVC). Measures of interpretation bias, anger, and alcohol use were administered at pre- and post-treatment and at one-month follow-up. IBM-H led to greater improvements in interpretation bias compared to HVC at post and follow-up. IBM-H also led to greater reductions in trait anger than HVC, though this was an indirect effect mediated by changes in interpretation bias. Further, IBM-H led to lower anger expression than HVC; this was a direct (non-mediated) effect. Lastly, both conditions reported decreases in alcohol use and consequences following treatment, though there were no significant differences between them. These findings provide initial support for the utility of IBM-H as a brief non-confrontational intervention for AUD with elevated trait anger. Limitations and future research directions are discussed.

Prevention of allograft HCV recurrence with peri-transplant human monoclonal antibody MBL-HCV1 combined with a single oral direct-acting antiviral: A proof-of-concept study

Patients with active hepatitis C virus (HCV) infection at transplantation experience rapid allograft infection, increased risk of graft failure and accelerated fibrosis. MBL-HCV1, a neutralizing human monoclonal antibody (mAb) targeting the HCV envelope, was combined with a licensed oral direct-acting antiviral (DAA) to prevent HCV recurrence post-transplant in an open-label exploratory efficacy trial. Eight subjects received MBL-HCV1 beginning on the day of transplant with telaprevir initiated between days 3 and 7 post-transplantation. Following FDA approval of sofosbuvir, two subjects received MBL-HCV1 starting on the day of transplant with sofosbuvir initiated on day 3. Combination treatment was administered for 8-12 weeks or until the stopping rule for viral rebound was met. The primary endpoint was undetectable HCV RNA at day 56 with exploratory endpoints of sustained virologic response (SVR) at 12 and 24 weeks post-treatment. Both subjects receiving mAb and sofosbuvir achieved SVR24. Four of eight subjects in the mAb and telaprevir group met the primary endpoint; one subject achieved SVR24 and three subjects relapsed 2-12 weeks post-treatment. The other four subjects experienced viral breakthrough. There were no serious adverse events related to study treatment. This proof-of-concept study demonstrates that peri-transplant immunoprophylaxis combined with a single oral direct-acting antiviral in the immediate post-transplant period can prevent HCV recurrence.

Hostile interpretation bias in depression

BACKGROUND

Research suggests an important relationship between interpretation bias, hostility and Major Depressive Disorder (MDD). Extant literature has yet to examine hostile interpretation bias in clinically depressed samples; the current studies sought to fill this gap.

METHOD

Study 1 participants included undergraduates who met criteria for MDD (n=36) or no anxiety or mood diagnosis (n=35). Each participant completed a structured clinical interview along with measures of depression, hostile interpretation bias, and trait hostility. In Study 2, a sample of treatment-seeking individuals with elevated trait anger completed measures of depression, hostile interpretation bias, and trait anger.

RESULTS

Study 1 demonstrated that, relative to the non-depressed group, individuals with depression displayed greater hostile interpretation bias but comparable levels of trait hostility. In Study 2, greater hostile interpretation bias was associated with greater depressive symptoms, and this relationship was independent of co-occurring trait anger.

LIMITATIONS

The correlational nature of these studies precludes interpretation of causal relationships between constructs. Additionally, replication of these results should be sought in a larger, more diverse sample.

CONCLUSION

Overall, the findings suggest hostile interpretation bias may play a unique role in depression and could be a treatable feature of interpersonal mechanisms maintaining MDD.

Is worst-event trauma type related to PTSD symptom presentation and associated features?

Posttraumatic stress disorder (PTSD) is generally assessed with reference to a "worst-event" (index) trauma, though little research has examined whether symptom presentation and comorbidity differ across worst-events. Data from individuals meeting lifetime PTSD criteria in the National Comorbidity Survey-Replication (N=398) were used to examine relations between PTSD presentation and comorbidity with the three most commonly reported "worst-event" trauma types: sexual trauma, non-sexual physical violence, and unexpected death of a loved one. Sexual trauma and non-sexual physical violence were associated with more symptomatic presentation of PTSD and lifetime trauma types compared to other worst-events. Non-sexual physical violence was associated with comorbid substance use disorder, and unexpected death of a loved one was associated with comorbid depression. Inclusion of number of lifetime trauma types as a covariate rendered most, but not all associations non-significant. These findings suggest worst-event trauma type is related to some important differences in PTSD presentation.

Spin-State Effects on the Thermal Dihydrogen Release from Solid-State [MH(η2-H2)dppe2]+ (M = Fe, Ru, Os) Organometallic Complexes for Hydrogen Storage Applications

Mössbauer spectroscopy, experimental thermodynamic measurements, and computational studies were performed to investigate the properties of molecular hydrogen binding to the organometallic fragments [MHdppe₂]⁺ (M = Fe, Ru, Os; dppe =1,2-bis(diphenylphosphino)ethane) to form the dihydrogen complex fragments [MH(η²-H₂)dppe₂]⁺. Mössbauer spectroscopy showed that the dehydrogenated complex [FeHdppe₂]⁺ adopts a geometry consistent with the triplet spin state, transitioning to a singlet state complex upon addition of the dihydrogen molecule in a manner similar to the previously studied dinitrogen complexes. From simulations, this spin transition behavior was found to be responsible for the strong binding behavior experimentally observed in the iron complex. Spin-singlet to spin-singlet transitions were found to exhibit thermodynamics consistent with the 5d > 3d > 4d binding trend observed for other transition metal dihydrogen complexes. Finally, the method for distinguishing between dihydrogen and dihydride complexes based on partial quadrupole splittings observed in Mössbauer spectra was confirmed, providing a tool for further characterization of these unique species for Mössbauer active compounds.

Linguistic indicators of patient, couple, and family adjustment following breast cancer

BACKGROUND

This study examined how language reflective of emotional and social processes during a cancer-related discussion relates to patient, couple, and family adjustment after breast cancer. It investigated whether emotional expression or relational focus, manifested in language use, indicates healthy family coping following breast cancer.

METHODS

Family members each completed measures of adjustment (Family Environment Scale, Dyadic Adjustment Scale, and patient Profile of Mood States) and engaged in a 15-min family discussion about how they have coped with breast cancer. Transcripts from the discussion were submitted to a text-analysis software program to obtain frequency of positive and negative emotion words, and personal pronouns spoken by each family member. The relationship between self-reports of adjustment and frequency of language use during the family discussion was analyzed with regression models.

RESULTS

Partners' positive emotion words were indicative of better family adjustment, patients' negative emotion words indicated greater family conflict, and sons' and daughters' anger words indicated poorer adjustment, whereas their anxiety words indicated better family adjustment. Partner we-talk was related to better dyadic adjustment, and couples' 'you' was somewhat related to worse adjustment at all levels.

CONCLUSIONS

Important information about how a family copes with breast cancer can be obtained by attending to families' emotional and relational language. This study suggests that clinicians and members of families' support networks can gauge how well a family has adapted after the breast cancer experience by attending to the type of words that each family member uses to describe how they coped with breast cancer.

When Leaving Your Ex, Love Yourself

Divorce is a highly stressful event, and much remains to be learned about the factors that promote psychological resilience when marriages come to an end. In this study, divorcing adults ( N = 109) completed a 4-min stream-of-consciousness recording about their marital separation at an initial laboratory visit. Four judges rated the degree to which participants exhibited self-compassion (defined by self-kindness, an awareness of one’s place in shared humanity, and emotional equanimity) in their recordings. Judges evidenced considerable agreement in their ratings of participants’ self-compassion, and these ratings demonstrated strong predictive utility: Higher levels of self-compassion at the initial visit were associated with less divorce-related emotional intrusion into daily life at the start of the study, and this effect persisted up to 9 months later. These effects held when we accounted for a number of competing predictors. Self-compassion is a modifiable variable, and if our findings can be replicated, they may have implications for improving the lives of divorcing adults.

In-plane correlations in a polymer-supported lipid membrane measured by off-specular neutron scattering

Polymer-supported single lipid bilayers are models to study configurations of cell membranes. We used off-specular neutron scattering to quantify in-plane height-height correlations of interfacial fluctuations of such a lipid bilayer. As temperature decreased from 37 °C to 25 °C, the polymer swells and the polymer-supported lipid membrane deviates from its initially nearly planar structure. A correlation length characteristic of capillary waves changes from 30 μm at 37 °C to 11 μm at 25 °C, while the membrane bending rigidity remains roughly constant in this temperature range.

Mouse fibroblast cell adhesion studied by neutron reflectometry

Neutron reflectometry (NR) was used to examine live mouse fibroblast cells adherent on a quartz substrate in a deuterated phosphate-buffered saline environment at room temperature. These measurements represent the first, to our knowledge, successful visualization and quantization of the interface between live cells and a substrate with subnanometer resolution using NR. NR data, attributable to the adhesion of live cells, were observed and compared with data from pure growth medium. Independently of surface cell density, the average distance between the center of the cell membrane region and the quartz substrate was determined to be approximately 180 A. The membrane region ( approximately 80 A thick) contains the membranes of cells that are inhomogeneously distributed or undulating, likely conforming to the nonplanar geometry of the supporting adherence proteins. A second region of cell membranes at a greater distance from the substrate was not detectable by NR due to the resolution limits of the technique employed. Attachment of the live cell samples was confirmed by interaction with both distilled water and trypsin. Distinct changes in the NR data after exposure indicate the removal of cells from the substrate.

Novel polyaromatic-terminated transition metal complexes for the functionalization of carbon surfaces

In order to investigate the process of noncovalent adsorption on glassy carbon surfaces, two terpyridine ligands 4-pyren-1-yl-N-[5-([2,2';6',2'']terpyridin-4'-yloxy)-pentyl]-butyramide (tpy~py) and N-[5-([2,2';6',2'']terpyridin-4'-yloxy)-pentyl]-2-naphthamide (tpy~nap) as well as the homoleptic cobalt(II) complexes of these ligands (Co(tpy~py)(2)(PF(6))(2) and Co(tpy~nap)(2)(PF(6))(2)) were synthesized. Electrochemical measurements in solution were used to characterize the transport behavior of these complexes and to verify that the polyaromatic portion of each ligand did not dramatically influence the electronic properties of the transition metal complex. The adsorption of the cobalt complexes above on glassy carbon electrode surfaces was then examined using cyclic voltammetry and was found to be well described by Langmuir or Frumkin isotherms. The free energy of adsorption for Co(tpy~py)(2)(PF(6))(2) was considerably larger than that for Co(tpy~nap)(2)(PF(6))(2): -41 versus -30 kJ/mol.

Early stages of oxidative stress-induced membrane permeabilization: a neutron reflectometry study

Neutron reflectometry was used to probe in situ the structure of supported lipid bilayers at the solid-liquid interface during the early stages of UV-induced oxidative degradation. Single-component supported lipid bilayers composed of gel phase, dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and fluid phase, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), phospholipids were exposed to low-dose oxidative stress generated by UV light and their structures were examined by neutron reflectometry. An interrupted illumination mode, involving exposures in 15 min increments with 2 h intervals between subsequent exposures, and a continuous mode involving a single 60 (or 90) min exposure period were employed. In both cases, pronounced differences in the structure of the lipid bilayer after exposure were observed. Interrupted exposure led to a substantial decrease in membrane coverage but preserved its total thickness at reduced scattering length densities. These results indicate that the initial phase during UV-induced membrane degradation involves the formation of hydrophilic channels within the membrane. This is consistent with the loss of some lipid molecules we observe and attendant reorganization of residual lipids forming hemimicellar edges of the hydrophilic channels. In contrast, continuous illumination produced a graded interface of continuously varied scattering length density (and hence hydrocarbon density) extending 100-150 A into the liquid phase. Exposure of a DPPC bilayer to UV light in the presence of a reservoir of unfused vesicles showed low net membrane disintegration during oxidative stress, presumably because of surface back-filling from the bulk reservoir. Chemical evidence for membrane degradation was obtained by mass spectrometry and Fourier transform infrared spectroscopy. Further evidence for the formation of hydrophilic channels was furnished by fluorescence microscopy and imaging ellipsometry data.

Model lipid membranes on a tunable polymer cushion

A hydrated, surface-tethered polymer network capable of fivefold change in thickness over a 25-37 degrees C temperature range has been demonstrated via neutron reflectivity and fluorescence microscopy to be a novel support for single lipid bilayers in a liquid environment. As the polymer swells from 170 to 900 A, it promotes both in- and out-of-plane fluctuations of the supported membrane. The cushioned bilayer proved to be very robust, remaining structurally intact for 16 days and many temperature cycles. The promotion of membrane fluctuations offers far-reaching applications for this system as a surrogate biomembrane.

Failed tracheostomy under local anaesthesia…plan B?

Severe stridor of recent onset is a challenge to deal with because of the lack of investigations on which to base the management plan. We describe a case of an elderly lady who presented to us with a short history of severe stridor. We encountered unanticipated difficulties with tracheostomy under local anaesthesia as the thyroid was replaced by a diffuse mass and the airway had to be secured by an awake fibre-optic intubation. Awake fibre-optic intubation is thought to be a relative contraindication in acute upper airway obstruction, but occasionally tracheostomy under local anaesthesia may not be possible and in experienced hands an awake fibre-optic intubation is a reasonable alternative.

The Discrete Dynamics of Monotonically Decomposable Maps

We extend results of Gouzé and Hadeler (in Nonlinear World 1:23-34, 1994) concerning the dynamics generated by a map on an ordered metric space that can be decomposed into increasing and decreasing parts. Our main results provide sufficient conditions for the existence of a globally asymptotically stable fixed point for the map. Applications to discrete-time, stage-structured population models are given.

Emergency tracheal catheterization for jet ventilation: a role for the ENT surgeon?

Stridor causing respiratory failure is an ENT and anaesthetic emergency requiring prompt management to secure a clear airway. We describe a case of subacute partial upper airway obstruction due to a large laryngeal carcinoma in an 81-year-old male resulting in respiratory failure. The patient became apnoeic after gaseous induction of general anaesthesia, and after two failed intubation attempts an emergency transtracheal airway catheter was placed by the surgeon under direct vision below the cricothyroid membrane, as this had tumour involvement. The patient was subsequently manually jet-ventilated with ease until a formal tracheostomy was made. Where difficulties with tracheal anatomy are encountered due to the presence of pathology, the insertion of a temporary airway catheter for jet ventilation by the surgeon can buy valuable time and be life-saving.

Awake insertion of the laryngeal mask airway using topical lidocaine and intravenous remifentanil*

We assessed the use of intravenous remifentanil for the insertion of the laryngeal mask airway in 10 healthy awake volunteers, a technique primarily developed to facilitate functional magnetic resonance imaging studies of anaesthesia. Each volunteer received 200 microg glycopyrronium intravenously. Topical airway anaesthesia was effected by 4 ml nebulised lidocaine 4%, followed by 12 sprays of lidocaine 10%. Remifentanil was subsequently infused to achieve an initial target effect-site concentration of 2 ng.ml(-1); increments of 1 ng.ml(-1) were allowed with the maximum effect-site concentration limited to 6 ng.ml(-1). Insertion of the laryngeal mask airway was successful on the first attempt in all cases. The median (IQR [range]) target effect-site remifentanil concentration at insertion was 2.5 (2-3 [2-4]) ng.ml(-1). All volunteers were co-operative during the procedure and only one reported discomfort. Sore throat was a complication in all volunteers. We conclude that the technique allows successful insertion of the laryngeal mask airway in healthy awake volunteers under conditions that were safe and reproducible.

Influence of improved teaching on medical students’ acquisition and retention of drug administration skills

BACKGROUND

Drug administration error is a major problem causing substantial morbidity and mortality worldwide. Lack of education about drug administration appears to be a causative factor. We devised an online teaching module for medical students and assessed its short- and long-term efficacy.

METHODS

One hundred and thirty clinical medical students were invited to undertake additional, online, teaching about drug administration. Those participating were identified and the number of web pages viewed recorded. The students' knowledge retention was tested by means of drug administration questions incorporated into routine assessments and examinations over the next 6 months. Other indices of all students' performance were recorded to correct for confounding factors.

RESULTS

Just over half (52%) responded to the invitation to participate. The amount of interest they showed in the teaching module correlated positively with their performance in questions about drug administration, although the latter waned over time. Surprisingly, correcting for students' general ability and keenness revealed that the less able students were most likely to undertake the teaching module.

CONCLUSIONS

Additional online teaching about drug administration improves students' knowledge of the topic but clearly requires reinforcement; however, only about half the students took up the option. Medical students must acquire these fundamental skills, and online teaching can help. Medical educators must ensure that drug administration is taught formally to all students as part of the curriculum and must understand that it may require additional teaching.

Integrated approaches to academic anaesthesia - the Cambridge experience

There is mounting concern about the pressures experienced by University Departments of Anaesthesia, which, if lost, could threaten undergraduate peri-operative medicine teaching, development of critical appraisal skills among anaesthetists, and the future of coherent research programs. We have addressed these problems by establishing a foundation course in scientific methods and research techniques (the Cambridge SMART Course), complemented by competitive, fully funded, 12-month academic trainee attachments. Research conducted during academic attachments has been published and used to underpin substantive grant applications allowing work towards higher degrees. Following the attachment, a flexible scheme ensures safe reintroduction to clinical training. Research at consultant level is facilitated by encouraging applications for Clinician Scientist Fellowships, and by ensuring that the University Department champions, legitimises and validates the allocation of research time within the new consultant contract. We believe that these are important steps in safeguarding research and teaching in anaesthesia, critical care and peri-operative medicine.

A web-based system for teaching, assessment and examination of the undergraduate peri-operative medicine curriculum

Today's students are generally computer literate and have high expectations of university information technology resources. Most United Kingdom medical schools now provide networked computers for learning, research, communication and accessing the worldwide web. We have exploited these advances to augment and improve the teaching of peri-operative medicine and anaesthesia to medical students in our university, who are taught in several hospitals over a wide geographical area. Course material such as departmental induction information, lecture notes and assessment sheets can be accessed online, contributing to the smooth running of the course. Streamed videos and simulations allow students to familiarise themselves with common practical procedures in advance. Development of a web-based end of course assessment has resulted in substantially less administration and bureaucracy for course organisers and proved to be a valuable research tool. Students' and teachers' opinions of the new course structure have been overwhelmingly positive.

Childhood obesity: a challenge for the anaesthetist?

The definition of childhood obesity has not been standardized in the past, making studies difficult to compare. In spite of this, the increase in the incidence of childhood obesity is evident and has now reached epidemic proportions. Obese children experience few of the medical complications seen in obese adults. Respiratory physiology appears to be most affected, the degree of which is determined by the level of obesity. Although there is a considerable amount of information on the anaesthetic management of the obese adult, very little has been written concerning the obese child. There is less pathology in the obese child when compared with the adult but some evidence shows a higher likelihood of a critical incident occurring when anaesthetizing such children. This shows that we need to be as worried about anaesthetizing the obese child as we are for the obese adult. This concern should increase with increasing body mass index.

Effect of videotape feedback on anaesthetists' performance while managing simulated anaesthetic crises: a multicentre study

The aim of this study was to examine the performance of anaesthetists while managing simulated anaesthetic crises and to see whether their performance was improved by reviewing their own performances recorded on videotape. Thirty-two subjects from four hospitals were allocated randomly to one of two groups, with each subject completing five simulations in a single session. Individuals in the first group completed five simulations with only a short discussion between each simulation. Those in the second group were allowed to review their own performance on videotape between each of the simulations. Performance was measured by both 'time to solve the problem' and mental workload, using anaesthetic chart error as a secondary task. Those trainees exposed to videotape feedback had a shorter median 'time to solve' and a smaller decrease in chart error when compared to those not exposed to video feedback. However, the differences were not statistically significant, confirming the difficulties encountered by other groups in designing valid tests of the performance of anaesthetists.

The poverty of information systems management in home health agencies: implications for survivability

Home health agencies are increasingly being challenged to cope with economic, financial and clinical pressures. This study examines the extent to which home health agencies have cultivated their information systems as an aid for managing performance and external forces. Colorado and New Mexico home health agencies participated in the research project. The findings indicate that only modest investments have been made by respondents in their information systems. The typical respondent reports a personal computer-based system which addresses some financial reporting data, but which does not emphasize care delivery or contextual factors. The implications of these findings for the survivability of home health agencies are discussed.

Non-invasive assessment of shunt and ventilation/perfusion ratio in neonates with pulmonary failure

AIMS

To make non-invasive measurements of right to left (R-L) shunt and reduced ventilation/perfusion ratio (V(A)/Q) in neonates with pulmonary failure and to examine sequential changes in these variables after treatment.

METHODS

Twelve neonates with pulmonary failure were studied. They ranged in gestational age from 24 to 37 (median 27) weeks and were 1-39 (median 4) days old. Shunt and reduced V(A)/Q were derived from their effects on the relation between inspired oxygen pressure (PIO(2)) and arterial oxygen saturation measured with a pulse oximeter (SpO(2)). Pairs of PIO(2) v. SpO(2) data points were obtained by varying PIO(2) in a stepwise fashion. A computer algorithm based on a model of pulmonary gas exchange fitted a curve to these data. With PIO(2) on the abscissa, an increase in shunt produced a downward movement of the curve, whereas reducing V(A)/Q to < 0.8 shifted the curve to the right. The right shift gives a variable that is inversely related to V(A)/Q, the PIO(2) - PO(2) difference, where PO(2) is mixed capillary oxygen pressure.

RESULTS

Ten of the 12 infants on the first study day had large shunts (range 5.9-31.0%, median 19.9%, normal < 8%) and large PIO(2) - PO(2) differences (range 9.7-64.4 kPa, median 19.8 kPa, normal < 7 kPa) equivalent to a median V(A)/Q of 0.2 (normal median V(A)/Q = 0.8). Sequential improvement in shunt and V(A)/Q were shown in most infants after treatment. Sudden large changes in these variables were shown in two infants.

CONCLUSION

This simple non-invasive method distinguishes between shunt and reduced V(A)/Q in neonates with pulmonary failure.

Modelling non-linearities in the vestibulo-ocular reflex (VOR) after unilateral or bilateral loss of peripheral vestibular function

We recorded the vestibulo-ocular reflex (VOR) in 18 normal subjects, 50 patients with unilateral loss of vestibular function and 18 patients with bilateral loss of vestibular function. The unilateral cases had either partial loss (i.e. vestibular neuronitis or Meniere's disease) or total loss (i.e. vestibular nerve section), whereas bilateral cases had only partial loss (i.e. due to ototoxicity or to suspected microangiopathy, secondary to severe kidney disease). Tests were performed at 1/6-Hz passive head rotation in the dark, with peak head velocities ranging from 125 to 190 degrees/s. We report on the distinct VOR non-linearities observed in unilateral versus bilateral patients: whereas unilateral patients all exhibit an asymmetric hypofunction with decreasing VOR gain at higher head velocities, bilateral patients have a more severe but symmetric hypofunction associated with increasing VOR gain at higher head velocities. We present a model study that can duplicate the nature of these characteristics, based mainly on peripheral non-linear semicircular canal characteristics and secondary central compensation. Theoretical analyses point to the importance of clinical test parameters (rotation speed and frequency) in the determination of a functional VOR and the detection of reflex non-linearities, so that test protocols can seriously bias the evaluation of adequate functional recovery.

Inhibitors of the lipoxygenase pathway block development of Brugia malayi L3 in vitro

Brugia malayi L3 molt to the L4 stage in serum-free cultures supplemented with arachidonic, linoleic, or linolenic acids and the basidiomycetous yeast Rhodotorula minuta. These fatty acids are capable of entering the eicosanoid pathway of arachidonate metabolism, the pathway responsible for generating a number of biologically active mediators, including prostaglandins, leukotrienes, and lipoxins. To determine whether this pathway was required for L3 development, we added dual inhibitors of cyclooxygenase and lipoxygenase to in vitro cultures containing B. malayi L3. These compounds significantly inhibited L3 molting. To evaluate whether 1 or both of these pathways of arachidonate metabolism were involved in molting, we tested drugs inhibiting either cyclooxygenase or lipoxygenase. Lipoxygenase inhibitors blocked L3 molting, whereas cyclooxygenase inhibitors did not. To assess whether enzymes operating downstream of lipoxygenase were also involved in L3 molting, we added inhibitors of enzymes involved in leukotriene synthesis and found they were also capable of preventing development. We tested the same inhibitor panel on Dirofilaria immitis L3. A single lipoxygenase inhibitor and inhibitors of 2 different enzymes operating downstream of lipoxygenase disrupted D. immitis development. These results demonstrate that a lipoxygenase pathway product is required for molting of the infective stage larvae of filarial parasites.

Predicting and explaining cardiac rehabilitation attendance

BACKGROUND

A variety of factors influence patients' health behaviour; these are patterns of practitioner practice, patient characteristics and availability of resources.

OBJECTIVES

To examine patient-related factors (demographic, health, psychosocial characteristics) that may influence patients' attendance at cardiac rehabilitation programs and their subsequent behaviour change.

PATIENTS AND METHODS

A prospective cohort design was used. Three hundred four acute myocardial infarction and/or coronary artery bypass graft surgery patients from a tertiary care centre in a Western Canadian city were enrolled to participate in telephone interviews at two weeks and again at approximately six months after their hospital discharge. Measures of self-efficacy and behaviour performance for cardiac health maintenance and role resumption, motivation and social support were used at both interview times. A survey focusing on factors influencing patients' choices to attend cardiac rehabilitation programs was also administered at the interview six months after discharge.

RESULTS

Attendance at cardiac rehabilitation programs is not associated with patients' risk factor status, and elderly and rural-living patients are at particular risk for nonattendance.

CONCLUSIONS

Systematic mechanisms to guide the appropriate referral of patients to this health care resource and administer secondary prevention initiatives to those with limited access to resources need to be a priority in cardiovascular health care.

Psychosocial components of cardiac recovery and rehabilitation attendance

OBJECTIVE

To examine the relations between demographic factors, specific psychosocial factors, and cardiac rehabilitation attendance.

DESIGN

Cohort, repeated measures design.

SETTING

A large tertiary care centre in western Canada

PATIENTS

304 consecutive consenting patients discharged following acute myocardial infarction and/or coronary artery bypass graft surgery.

MAIN OUTCOME MEASURES

The Jenkins self-efficacy expectation scales and activity checklists of behaviour performance for maintaining health and role resumption, modified version of the self-motivation inventory, and the shortened social support scale.

RESULTS

Those who had higher role resumption behaviour performance scores at two weeks after discharge were significantly less likely to attend cardiac rehabilitation programmes. At six months after discharge, those who attended cardiac rehabilitation demonstrated higher health maintenance self-efficacy expectation and behaviour performance scores. Health maintenance self-efficacy expectation and behaviour performance improved over time. Women reported less social support but showed greater improvement in health maintenance self-efficacy expectation. Changes in self-efficacy scores were unrelated to-but changes in health maintenance behaviour performance scores were strongly associated with-cardiac rehabilitation attendance.

CONCLUSIONS

Cardiac patients and practitioners may have misconceptions about the mandate and potential benefits of rehabilitation programmes. Patients who resumed role related activities early and more completely apparently did not see the need to "rehabilitate" while those who attended cardiac rehabilitation programmes enhanced their secondary prevention behaviours.

Assessing future possible selves by gender and socioeconomic status using the anticipated life history measure

This is a report from the first phase of a longitudinal study of the ways young adults imagine their future lives. The future possible selves of 223 18- and 19-year-old adults were examined using the Anticipated Life History measure (ALH), a psychological instrument prompting participants to describe their future life course from their 21st birthday until their death. When the ALH narratives were coded for presence/absence of life events, female participants were more likely to predict career choice, marriage, children, divorce, and death of spouse than their male counterparts; when coded for psychological qualities, female participants demonstrated greater psychological complexity and awareness of future life role choices and conflicts. Participants with lower SES wrote ALH narratives with fewer altruistic acts, less awareness of life role complexity, and fewer anticipated conflicts and their resolutions than those with higher SES.

Investigating development of infective stage larvae of filarial nematodes

Lymphatic filariasis is a parasitic disease affecting millions of individuals and one of the leading causes of disability in the world. However, considering the magnitude of filariasis as a public health problem, relatively little is known about the basic biology of the disease and its causative agents, filarial nematodes. In this paper, the biology of the infective stage larvae of the nematodes responsible for lymphatic filariasis and the approaches used to study their development are reviewed.

The poverty of information systems management in home health agencies: implications for survivability

Home health agencies are increasingly being challenged to cope with economic, financial and clinical pressures. This study examines the extent to which home health agencies have cultivated their information systems as an aid for managing performance and external forces. Colorado and New Mexico home health agencies participated in the research project. The findings indicate that only modest investments have been made by respondents in their information systems. The typical respondent reports a personal computer-based system which addresses some financial reporting data, but which does not emphasize care delivery or contextual factors. The implications of these findings for the survivability of home health agencies are discussed.

Husbands' versus wives' fertility goals and use of contraception: the influence of gender context in five Asian countries

Using data from Pakistan, India, Malaysia, Thailand, and the Philippines, we explore how gender context influences (1) husband-wife concordance in the demand for children and (2) the impact of each spouse's fertility preferences on contraceptive use. We also explore whether the husband's pronatalism can explain the wife's unmet need for contraception. The results suggest that gender context has little net effect on couples' concordance, but influences the relative weight of husbands' and wives' preferences in determining contraceptive use. Analysis of women's unmet need for contraception suggests that the husbands' pronatalism contributes to wives' unmet need, but only to a relatively small degree, especially in settings where unmet need is high. This is the case because the proportion of couples with differing fertility goals is small in most communities.

Development of a serum-free system for the in vitro cultivation of Brugia malayi infective-stage larvae

Over the past several years, numerous attempts have been made to culture the infective-stage (L3) larvae of the human filarial parasite Brugia malayi in an in vitro system that promotes molting to the fourth larval stage (L4). Although there have been reports in the literature of successful L3 to L4 development in vitro, all of these systems have required serum supplementation. The complexity of serum as a culture supplement has made reproducibility of results and identification of specific factors necessary for L3 development problematic. We have developed a serum-free in vitro system consisting of RPMI 1640 supplemented with one of three fatty acids (arachidonic, linoleic, or linolenic) that supports consistent and reproducible molting to the fourth larval stage in the presence of a basidiomycetous yeast, Rhodotorula minuta. Coculture with this yeast, initially isolated as a culture contaminant, is required for successful molting. In serum-free cultures lacking R. minuta, L3 larvae survive for upward of 2 weeks, but do not molt successfully. The L4 larvae generated in cultures containing R. minuta are well formed, as seen by light and electron microscopy, and are capable of further development upon transfer to a permissive host. This culture system is inexpensive and easily reproducible, thus making it a useful tool for studying the requirements for the development of B. malayi L3.

Tetracycline inhibits development of the infective-stage larvae of filarial nematodes in vitro

In recent years, studies have linked tetracycline treatment of filaria-infected animals with reduced adult worm burdens and decreased levels of microfilaremia. These observations are believed to be attributable to clearance of Wolbachia, intracellular rickettsial-like organisms found within filarial tissues. Although maximal worm reductions were observed when treatment was initiated early in infection, it is not known whether tetracycline inhibits development of infective-stage larvae. To address this issue, we studied the effect of tetracycline on three different species of filarial nematodes, Brugia malayi, Brugia pahangi, and Dirofilaria immitis, in a serumfree in vitro system supporting molting to the fourth larval stage. Tetracycline was capable of inhibiting L3 to L4 molting within a dosage range similar to that reported for susceptible rickettsial organisms. However, Wolbachia DNA could still be detected in nematodes from tetracycline-treated cultures. In addition, three other antibiotics with anti-rickettsial and anti-chlamydial activity (chloramphenicol, erythromycin, and ciprofloxacin) failed to inhibit L3 to L4 molting. Although tetracycline is capable of completely blocking molting of infective-stage larvae, it remains possible that this effect is due to pharmacological activities unrelated to its anti-rickettsial functions.