Maintenance factors for persistence of bulimic pathology: a prospective natural history study

OBJECTIVE

To characterize the natural course of bulimia nervosa and identify potential maintenance factors that predict persistence of bulimic pathology in order to advance knowledge of processes that perpetuate this eating disturbance and permit the design of more efficacious treatments.

METHOD

We followed 96 women with threshold or subthreshold bulimia nervosa over a 1-year period with quarterly interviews.

RESULTS

There were high rates of remission and relapse on a month-to-month basis, but remission became more likely to persist after a period of approximately 4 months of symptom abstinence. Initial elevations in thin-ideal internalization, expectations for reward from eating, and binge frequency predicted greater time to remission of binge eating. Initial elevations in dietary restraint and compensatory behavior frequency predicted greater time to remission of compensatory behaviors.

DISCUSSION

Results imply that treatments for eating disorder may be more effective if they can reduce thin-ideal internalization, eating expectancies, and ineffective dieting and produce rapid cessation of binge eating and compensatory behaviors.

Prediction ofin vivodrug interactions with eplerenone in man fromin vitrometabolic inhibition data

1: The inhibition kinetics of eplerenone (EP) 6beta-hydroxylation by 10 drugs were determined in vitro using human liver microsomes. Inhibition factors were calculated from in vitro inhibition constant (Ki) and three different inhibitor Cmax values (liver Cmax of total and unbound inhibitor, and maximum influx concentration of inhibitor into the liver). Subsequently, the inhibition factors were compared with available pharmacokinetic data derived from clinical interaction trials conducted by Pfizer involving EP and these drugs. EP was also evaluated for its effect on the metabolism of 10 drugs in vitro, and again the in vitro data were compared with results from the clinical trials. 2: The Ki values for the inhibition of EP 6beta-hydroxylation by cisapride, cyclosporine, digoxin, erythromycin, fluconazole, ketoconazole, midazolam, saquinavir, simvastatin and verapamil were 2.90, 1.24,>75.0, 9.50, 59.0, 0.160, 8.10, 0.546, 6.23 and 13.3 microM, respectively. Among the three methods, inhibition factors (Rb) calculated using the Ki and estimated liver Cmax values of the unbound drug were best correlated with the in vivo area under the curve-fold increases of EP in humans. The Rb values for the drugs listed above were 1.04, 1.69, 1.00, 2.17, 2.24, 4.90, 1.00, 1.82, 1.01 and 1.04, respectively, and the in vivo area under the curve-fold increases of EP by these drugs were 1.04, 1.16, 0.930, 2.87, 2.24, 5.39, 1.00, 2.07, 1.03 and 1.98, respectively. 3: EP did not have any significant effects on the drugs tested in vitro or in the clinic. 4: Using in vitro metabolic interaction data, human in vivo pharmacokinetic interactions involving EP could be predicted nearly quantitatively. The lack of effects of EP on the pharmacokinetics of other drugs in man was also suggested in the in vitro data.

A prospective test of cognitive vulnerability models of depression with adolescent girls

This study sought to provide a more rigorous prospective test of two cognitive vulnerability models of depression with longitudinal data from 496 adolescent girls. Results supported the cognitive vulnerability model in that stressors predicted future increases in depressive symptoms and onset of clinically significant major depression for individuals with a negative attributional style, but not for those with a positive attributional style, although these effects were small. This model appeared to be specific to depression, in that it did not predict future increases in bulimia nervosa or substance abuse symptoms. In contrast, results did not support the integrated cognitive vulnerability self-esteem model that asserts stressors should only predict increased depression for individuals with a confluence of negative attributional style and low self-esteem, and this model did not appear to be specific to depression.

Relations of bulimic symptom frequency and intensity to psychosocial impairment and health care utilization: results from a community-recruited sample

OBJECTIVE

To determine the frequency and intensity of bulimic symptoms related to psychosocial impairment and health care utilization.

METHOD

Females (N = 1231, M age = 17.7, range 13-55) from four community-recruited samples varying in bulimic pathology completed the eating disorder examination, social adjustment scale, and health survey utilization scale.

RESULTS

Co-occurrence of binge eating and compensatory behaviors and solely compensatory behaviors >or=1 time/month were associated with elevations in psychosocial impairment. Co-occurrence of both binge eating and compensatory behaviors and solely compensatory behaviors >or=8 times/month were related to greater service utilization. Solely binge eating and duration of bulimic behaviors were unrelated to these functional outcomes. Overvaluation of body shape and weight showed significant linear relations to the functional outcomes.

CONCLUSION

Results suggest that current diagnostic thresholds for bulimia nervosa may be too high when considering functional impairment and service utilization and that different cut-points need to be considered for different bulimic symptoms.

Randomized trial of a brief depression prevention program: an elusive search for a psychosocial placebo control condition

This trial compared a brief group cognitive-behavioral (CBT) depression prevention program to a waitlist control condition and four placebo or alternative interventions. High-risk adolescents with elevated depressive symptoms (N=225, M age=18, 70% female) were randomized to CBT, supportive-expressive group intervention, bibliotherapy, expressive writing, journaling, or waitlist conditions and completed assessments at baseline, termination, and 1- and 6-month follow-up. All five active interventions showed significantly greater reductions in depressive symptoms at termination than waitlist controls; effects for CBT and bibliotherapy persisted into follow-up. CBT, supportive-expressive, and bibliotherapy participants also showed significantly greater decreases in depressive symptoms than expressive writing and journaling participants at certain follow-up points. Findings suggest there may be multiple ways to reduce depressive symptoms in high-risk adolescents, although expectancies, demand characteristics, and attention may have contributed to the observed effects.

Experimental test of the affect-regulation theory of bulimic symptoms and substance use: a randomized trial

OBJECTIVE

Conduct a randomized trial to test whether a cognitive behavioral intervention designed to decrease depressive symptoms produces subsequent decreases in bulimic and substance use symptoms.

METHOD

Female participants (N = 145) with elevated depressive symptoms were randomly assigned to a 4-session depression intervention or a measurement-only condition and assessed through 6-month follow-up.

RESULTS

Relative to control participants, intervention participants showed decreases in depressive symptoms. Intervention participants also showed significantly greater reductions in bulimic symptoms, but not substance use, and change in depressive symptoms mediated this effect for bulimic symptoms.

CONCLUSION

The results provide experimental support for the theory that affect disturbances contribute to bulimic pathology, but do not support the affect regulation theory of substance use.

Dissonance and healthy weight eating disorder prevention programs: a randomized efficacy trial

In this trial, adolescent girls with body dissatisfaction (N = 481, M age = 17 years) were randomized to an eating disorder prevention program involving dissonance-inducing activities that reduce thin-ideal internalization, a prevention program promoting healthy weight management, an expressive writing control condition, or an assessment-only control condition. Dissonance participants showed significantly greater reductions in eating disorder risk factors and bulimic symptoms than healthy weight, expressive writing, and assessment-only participants, and healthy weight participants showed significantly greater reductions in risk factors and symptoms than expressive writing and assessment-only participants from pretest to posttest. Although these effects faded over 6-month and 12-month follow-ups, dissonance and healthy weight participants showed significantly lower binge eating and obesity onset and reduced service utilization through 12-month follow-up, suggesting that both interventions have public health potential.

A microplate spectrofluorometric assay for bacterial biofilms

A spectrofluorometric assay was developed for quantification of bacterial biofilms grown on a microtiter plate. The method involved staining biofilms formed by gram-negative and gram-positive bacteria with wheat germ agglutinin-Alexa Fluor 488 conjugate, which selectively binds to N-acetylglucosamine residues in biofilms. The fluorescence of stained biofilms was measured with a fluorescent plate reader. This method was compared with a widely used microplate colorimetric assay involving crystal violet staining of biofilms formed by both gram-negative and gram-positive bacteria. A strong linear association existed between the two methods (r (2)=0.99/0.94). Being more sensitive and specific as compared to colorimetric method, the spectrofluorometric assay provides a better alternative for quantification and characterization of bacterial biofilms.

Evaluation of a healthy-weight treatment program for bulimia nervosa: a preliminary randomized trial

OBJECTIVE

Conduct a randomized treatment trial to test whether healthy dieting maintains bulimic symptoms or effectively reduces this eating disturbance.

METHODS

Female participants (n=85) with full- and sub-threshold bulimia nervosa were randomly assigned to a 6-session healthy dieting intervention or waitlist condition and assessed through 3-month follow-up.

RESULTS

Relative to control participants, intervention participants showed modest weight loss during treatment and demonstrated significant improvements in bulimic symptoms that persisted through follow-up.

DISCUSSION

These preliminary results suggest that this intervention shows potential for the treatment of bulimia nervosa and may be worthy of future refinement and evaluation. Results also provide experimental evidence that dieting behaviors do not maintain bulimia nervosa, suggesting the need to reconsider maintenance models for this eating disorder.

A prospective test of the stress-buffering model of depression in adolescent girls: no support once again

The stress-buffering model posits that social support mitigates the relation between negative life events and onset of depression, but prospective studies have provided little support for this assertion. The authors sought to provide a more sensitive test of this model by addressing certain methodological and statistical limitations of past studies with prospective data from 496 adolescent girls. Deficits in peer support predicted increases in depressive symptoms, and negative life events predicted onset of depressive pathology. However, none of the 14 prospective tests provided support for the stress-buffering model despite sufficient power. Results provide scant support for the stress-buffering model and suggest that it might be time to shift attention to alternative multivariate models concerning these risk factors.

Measuring the built environment: validity of a site survey instrument for use in urban settings

There are few reliable measures of place with which to study the effects of socio-economic context on health. We report on the development and inter-rater reliability of a 27-item observer-rated built environment site survey checklist (BESSC). Across eleven 'housing areas' (defined as areas of homogeneity in housing form) and two raters, kappa coefficients were > or =0.5 for fifteen categorical items, and intra-class correlation coefficients exceeded 0.6 for a further three continuous measures. Ratings on several BESSC items were associated to a statistically significant degree with the prevalence of depression and residents' dissatisfaction with 'their area as a place to live'. BESSC items may prove to be valuable descriptors of the urban built environment in future studies.

Effect of patient weight on the anticoagulant response to adjusted therapeutic dosage of low-molecular- weight heparin for the treatment of venous thromboembolism

Data evaluating the safety of using weight-based dosing of low-molecular-weight heparin (LMWH) in obese patients are limited. Some manufacturers have recommended a maximum daily dose of LMWH not to be exceeded. The purpose of this study was to determine if body weight influenced the anticoagulant response to a weight-based dose of LMWH for the treatment of venous thromboembolism. Patients with serum creatinine levels < 150 micromol/l receiving the LMWH, dalteparin 200 anti-Xa IU/kg based on actual body weight subcutaneously once daily for the treatment of deep vein thrombosis or pulmonary embolism, were eligible for the study. Patients received a minimum of 5 days LMWH treatment. Patients had peak anti-Xa levels (IL Test Chromogenic assay) measured 3-4 h following their day 3 injection and trough anti-Xa levels measured immediately prior to injections on day 3 and 5. No dose adjustments were made on the basis of the anti-Xa levels. Patients were a priori stratified into three weight classes: (A) within 20% of ideal body weight (IBW) (n = 13); (B) 20-40% of IBW (n = 14), and (C) greater than 40% of IBW (n = 10). The largest patient weighed 190 kg and had a body mass index of 58. Mean daily LMWH doses were 14,030, 17,646 and 23, 565 IU for groups A, B and C, respectively. Mean (SD) trough anti-Xa levels on day 3 were 0.12 (0.05) anti-Xa IU/ml for group A, 0.11 (0.03) anti-Xa IU/ml for group B and 0.11 (0.03) anti-Xa IU/ml for group C (p > 0.2). Similar trough anti-Xa levels were observed on day 5. Mean (SD) peak anti-Xa levels on day 3 were 1.01 (0.20) anti-Xa IU/ml, 0.97 (0.21) anti-Xa IU/ml and 1.12 (0.22) anti-Xa IU/ml for groups A, B and C, respectively (p > 0.2). No thromboembolic or bleeding complications occurred during LMWH therapy in any patients. These findings suggest that body mass does not appear to have an important effect on the response to LMWH up to a weight of 190 kg in patients with normal or near normal renal function.

Evaluation of polyethylene terephthalate for ABO and Rh typing and alloantibody screening

BACKGROUND

For many years, hospitals and laboratories have used evacuated glass tubes for blood collection. To improve the safety of blood collection, plastic polyethylene terephthalate (PET) tubes (Vacutainer PLUS, Becton Dickinson) have been developed. The objectives of this study were to compare the accuracy of ABO grouping, Rh typing, and antibody screening of blood samples collected in plastic tubes with that in glass tubes and to determine if refrigerated blood samples collected in plastic tubes remained stable over a 28-day period.

STUDY DESIGN AND METHODS

Samples were collected from 121 volunteers, at least 30 from each of the A, B, O, and AB blood groups, in four types of Vacutainer tubes: silica-coated plastic, K(2) EDTA plastic, uncoated glass, and K(2) EDTA glass. Samples from each tube were tested for ABO group and Rh type by use of the microtyping gel identification card system and the tube method. A three-cell antibody screen was performed by the microtyping gel card technique with a monospecific IgG reagent. Initial samples were tested within 3 hours of collection. Refrigerated samples were retested for ABO and Rh type and antibody screening 1, 2, 21, and 28 days later. Agreement between test results was determined by using Cohen's Kappa statistic.

RESULTS

Complete agreement was observed between the ABO and Rh typing results in samples drawn into glass and plastic tubes of both the EDTA and nonanticoagulated type (kappa = 1.0). In retesting, there were no examples of a change in ABO or Rh type over the 28-day study period. Only two alloantibodies (1.7%) were identified in the 121 samples, and no difference was observed in alloantibody expression in either plastic or glass Vacutainer tubes over the 28-day study period.

CONCLUSION

Samples collected into the PET serum or EDTA tubes provided accurate ABO and Rh typing results that remained consistent over a 28-day period. Samples collected in these tubes also appeared to enable accurate alloantibody identification. However, the number of alloantibodies identified in this study was small, and this result should be confirmed in a larger series.

Myelopoietin, an engineered chimeric IL-3 and G-CSF receptor agonist, stimulates multilineage hematopoietic recovery in a nonhuman primate model of radiation-induced myelosuppression

Myelopoietins (MPOs) constitute a family of engineered, chimeric molecules that bind and activate the IL-3 and G-CSF receptors on hematopoietic cells. This study investigated the in vivo hematopoietic response of rhesus monkeys administered MPO after radiation-induced myelosuppression. Animals were total body irradiated (TBI) in 2 series, with biologically equivalent doses consisting of either a 700 cGy dose of Cobalt-60 ((60)Co) gamma-radiation or 600 cGy, 250 kVp x-irradiation. First series: On day 1 after 700 cGy irradiation, cohorts of animals were subcutaneously (SC) administered MPO at 200 microg/kg/d (n = 4), or 50 microg/kg/d (n = 2), twice daily, or human serum albumin (HSA) (n = 10). Second series: The 600 cGy x-irradiated cohorts of animals were administered either MPO at 200 microg/kg/d, in a daily schedule (n = 4) or 0.1% autologous serum (AS), daily, SC (n = 11) for 23 days. MPO regardless of administration schedule (twice a day or every day) significantly reduced the mean durations of neutropenia (absolute neutrophil count [ANC] < 500/microL) and thrombocytopenia (platelet < 20,000/microL) versus respective control-treated cohorts. Mean neutrophil and platelet nadirs were significantly improved and time to recovery for neutrophils (ANC to < 500/microL) and platelets (PLT < 20,000/microL) were significantly enhanced in the MPO-treated cohorts versus controls. Red cell recovery was further improved relative to control-treated cohorts that received whole blood transfusions. Significant increases in bone marrow-derived clonogenic activity was observed by day 14 after TBI in MPO-treated cohorts versus respective time-matched controls. Thus, MPO, administered daily was as effective as a twice daily schedule for multilineage recovery in nonhuman primates after high-dose, radiation-induced myelosuppression.

The effects of motion on parametric fMRI analysis techniques

Subject motion during the time course of functional activation studies has been shown to cause spurious signals which can mimic 'true' activation. Therefore, the importance of motion correction has been widely recognized. Correction with post-processing using image registration software is common practice in functional imaging and analysis. Many image registration algorithms, developed for analysis requirements other than fMRI, assume rigid body motion. Although these techniques are now routinely used by a number of groups, rigid body coregistration has not yet been shown to reduce the effects of motion to an acceptable level in fMRI analysis, i.e. the effects on resulting correlation analysis directly. In this paper we have used volume data to assess rigid body co-registration in terms of motion artefacts for the different correlation approaches used in fMRI. We have developed a new way of visualizing motion effects in correlation analysis based on generating a scatter plot of correlation score against local image gradient. This technique has been tested on fMRI data sets from a functional paradigm suffering from motion correlated artefacts, with and without rigid body motion correction. Although we do not attempt to estimate the actual residual motion, this technique can be used to verify the results of analysis and select regions of relatively unambiguous activation. This paper assesses directly the rigid body assumption and proves the need for, and effectiveness of, co-registration for all correlation based analysis techniques. The specific differences between the popular correlation forms used are investigated and explained. We show that for certain forms of correlation analysis the effects of motion, while not removed altogether, are effectively statistically eliminated.

New chemotherapy options for the treatment of malignant gliomas

Chemotherapy remains part of the treatment triad that includes surgery and radiation therapy for the management of malignant gliomas. In recent years there has been an increased understanding of the molecular pathways of malignant transformation. Based on this research, new drugs have been evaluated, with specific cellular targets in mind that can be modified or inhibited. Many of these agents are now being tested in phase I and II clinical trials and have shown some promising results. Clearly, not all patients with malignant gliomas respond equally to chemotherapy. Recent evidence suggests that certain molecular markers may predict chemosensitivity in some tumor types, particularly anaplastic oligodendroglioma. This article reviews recent trends in the use of chemotherapy and clinical trials of new therapies for adults with malignant gliomas.

Everyday planning difficulties following traumatic brain injury: a role for autobiographical memory

The present study examines the role of autobiographical memory in describing how to perform both open-ended and closed everyday activities in 12 patients suffering traumatic brain injury and 12 aged-matched controls. The frequency (high versus low) of performing the activities was also manipulated. Patients seemed less well able to benefit from using specific autobiographical memories; they reported using significantly fewer specific autobiographical memories for describing how to perform low-frequency activities and significantly more such memories for high-frequency activities compared with controls. The quality of their descriptions was also significantly poorer for the open-ended activities. Finally, significant correlations were found between the quality of the descriptions and the retrieval of specific autobiographical memories for the controls only. The importance of the retrieval of specific autobiographical memories for everyday problem-solving is discussed.

Intradermal recombinant human nerve growth factor induces pressure allodynia and lowered heat-pain threshold in humans

Nerve growth factor (NGF) plays a biologic role in the development and maintenance of sympathetic and small sensory neurons. Because it facilitates nerve fiber regeneration, lowers heat-pain threshold (hyperalgesia), and prevents or improves nerve dysfunction in experimental neuropathy, it is being considered as a putative treatment for certain human polyneuropathies. In 16 healthy subjects, we tested whether intradermal injection of minute doses of recombinant human NGF (1 or 3 micrograms) compared with saline induces hyperalgesia or alters cutaneous sensation (at the site of injection) as measured by symptom scores, clinical examination, or quantitative sensory testing with Computer Assisted Sensory Examination (CASE IV). Most subjects had, as their only symptom, localized tenderness of the NGF-injected site and only when the site was bumped or compressed. Slight discomfort developed in volar wrist structures (with flexion of fingers) or tenderness of deep structures to palpation over the bicipital groove or supraclavicular region. The Neuropathy Symptoms and Change questionnaire indicated that pressure allodynia was significantly localized to the NGF-injected side from 3 hours to 21 days after injections. Light stroking of the skin did not induce tactile allodynia. Compression of injected sites induced pressure allodynia that occurred more frequently and significantly on the NGF-injected side after 3 hours and was maintained for several weeks. No abnormality of vibratory or cooling detection threshold developed from NGF injection. By contrast, heat-pain threshold (HP 0.5, p = 0.003) and an intermediate level of heat-pain (HP 5.0, p < 0.001) were significantly lowered 1, 3, and 7 days (and in some cases at 3 hours and 14 and 21 days) after NGF injection. The time course of pressure allodynia and heat-pain hyperalgesia is too rapid to be explained by uptake of NGF by nociception terminals, retrograde transport, and upregulation of pain modulators. Local tissue mechanisms appear to be implicated. It remains to be tested whether recombinant human NGF prevents, stabilizes, or ameliorates small fiber human neuropathies.

Lateral advantages in same-different comparison of two-note, dichotically presented chords to a successively-presented probe

An experiment is reported which examines same-different comparison of dichotically presented, two-tone chords to a probe. A prediction of a fast 'same' response indicative of holistic processing was tested. Stimuli and probes were systematically related by similarity relationships established in a previous experiment. No evidence was found for fast 'same' responding overall or on either ear, but a right ear advantage for the making of difficult 'different' decisions was found for accuracy. It is argued that the concepts of analytic and holistic processing may require some redefinition and a preliminary account is offered in terms of Krueger's [23] noisy operator model.

Superior vena cava thrombosis and chylothorax: relationship in pediatric nephrotic syndrome

We report a 40-month-old black male with nephrotic syndrome who developed chylothorax associated with superior vena cava (SVC) thrombosis. To our knowledge, this is the third reported case of spontaneous SVC thrombosis in a nephrotic patient and the first in which chylothorax was also present. Ultrasonography of the pleura and thoracic vasculature was invaluable in making the diagnosis and monitoring the resolution of this condition during treatment. Contrary to previous reports, thoracic chylous effusions complicating uncontrolled nephrotic syndrome do not originate exclusively as a consequence of abdominal pathology, but rather as this case demonstrates, they can occur from lymphatic obstruction caused by thoracic vein thrombosis.

Acceleration of hematopoietic reconstitution with a synthetic cytokine (SC-55494) after radiation-induced bone marrow aplasia

The synthetic cytokine (Synthokine) SC-55494 is a high-affinity interleukin-3 (IL-3) receptor ligand that stimulates greater in vitro multilineage hematopoietic activity than native IL-3, while inducing no significant increase in inflammatory activity relative to native IL-3. The aim of this study was to investigate the in vivo hematopoietic response of rhesus monkeys receiving Synthokine after radiation-induced marrow aplasia. Administration schedule and dose of Synthokine were evaluated. All animals were total-body irradiated (TBI) with 700 cGy 60Co gamma radiation on day 0. Beginning on day 1, cohorts of animals (n = 5) received Synthokine subcutaneously (SC) twice daily with 25 micrograms/kg/d or 100 micrograms/kg/d for 23 days or 100 micrograms/kg/d for 14 days. Control animals (n = 9) received human serum albumin SC once daily at 15 micrograms/kg/d for 23 days. Complete blood counts were monitored for 60 days postirradiation and the durations of neutropenia (NEUT; absolute neutrophil count [ANC] < 500/microL) and thrombocytopenia (THROM; platelet count < 20,000/microL) were assessed. Synthokine significantly (P < .05) reduced the duration of THROM versus the HSA-treated animals regardless of dose or protocol length. The most striking reduction was obtained in the animals receiving 100 micrograms/kg/d for 23 days (THROM = 3.5 v 12.5 days in HSA control animals). Although the duration of NEUT was not significantly altered, the depth of the nadir was significantly lessened in all animal cohorts treated with Synthokine regardless of dose versus schedule length. Bone marrow progenitor cell cultures indicated a beneficial effect of Synthokine on the recovery of granulocyte-macrophage colony-forming units that was significantly higher at day 24 post-TBI in both cohorts treated at 25 and 100 micrograms/kg/d for 23 days relative to the control animals. Plasma pharmacokinetic parameters were evaluated in both normal and irradiated animals. Pharmacokinetic analysis performed in irradiated animals after 1 week of treatment suggests an effect of repetitive Synthokine schedule and/or TBI on distribution and/or elimination of Synthokine. These data show that the Synthokine, SC55 94, administered therapeutically post-TBI, significantly enhanced platelet recovery and modulated neutrophil nadir and may be clinically useful in the treatment of the myeloablated host.