Intrathecal Dexamethasone in Febrile Infection-Related Epilepsy Syndrome: A Case Report

Objectives

Febrile infection-related epilepsy syndrome (FIRES) is characterized by explosive onset refractory status epilepticus (RSE) in healthy individuals that is refractory to antiseizure medication (ASM), continuous anesthetic infusions (CIs), and immunomodulators. Recently, a case series of patients receiving intrathecal dexamethasone (IT-DEX) was reported with improved RSE control.

Methods

We present a child with FIRES with favorable outcome after receiving concomitant anakinra and IT-DaEX. A 9-year-old male patient presented with encephalopathy following a febrile illness. He developed seizures evolving to RSE refractory to multiple ASM, 3 CIs, steroids, IVIG, plasmapheresis, ketogenic diet (KD), and anakinra. After continued seizures and inability to wean off CI, IT-DEX was initiated.

Results

He received 6 doses of IT-DEX with resolution of RSE, rapid wean off CI, and improved inflammatory markers. At discharge, he was ambulating with assistance, speaking 2 languages, and ingesting food orally.

Discussion

FIRES is a neurologically devastating syndrome with high mortality and morbidity. Proposed guidelines and various treatment strategies are becoming available in the literature. Although treatment with KD, anakinra, and tocilizumab has been successful in previous FIRES cases, our results suggest that the addition of IT-DEX may allow for faster weaning off CI and better cognitive outcomes when initiated early in the course.

A randomized, double-blind, placebo- and positive-controlled crossover study of the effects of durlobactam on cardiac repolarization in healthy subjects

Durlobactam (formerly ETX2514) is a diazabicyclooctane β-lactamase inhibitor that inhibits class A, C, and D β-lactamases. Sulbactam combined with durlobactam has in vitro and in vivo activity against Acinetobacter baumannii including carbapenem- and colistin-resistant isolates and is being developed for treating serious infections due to A. baumannii. The effect of a single supratherapeutic dose of durlobactam on the heart rate corrected QT interval (QTc) was evaluated in healthy subjects in a placebo- and active-controlled, single-infusion, three-way crossover study. Subjects were randomized to 1 of 6 sequences that included a single 3-h i.v. infusion of durlobactam 4 g (supratherapeutic dose), a single 3-h i.v. infusion of placebo, and a single 3-h i.v. infusion of placebo plus a single oral dose of moxifloxacin 400 mg given open-label at the end of the i.v. infusion. In each treatment period, Holter electrocardiogram (ECG) measurements were obtained from predose through 24 h post-start of infusion. For the primary ECG end point, placebo-corrected change-from-baseline corrected QT Fridericia's formula (ΔΔQTcF), no significant change was observed with durlobactam. A concentration-QT analysis demonstrated no significant effect of durlobactam on ECG parameters, including QT interval prolongation. Thus, durlobactam has a low risk for prolonging the QT interval and is unlikely to produce any proarrhythmic effects.

1490. Serious Infections Caused by Carbapenem Susceptible and Carbapenem Resistant Acinetobacter baumannii-calcoaceticus Complex - A Retrospective Review

Background

Increasing resistance to available antibiotics, including carbapenems, is limiting effective treatment options for serious Acinetobacter baumannii-calcoaceticus (ABC) complex infections that are associated with high mortality. This multi-center retrospective analysis is to describe the natural history and outcomes of serious ABC infections.

Methods

This was a retrospective review of 125 cases of ABC infections from United States (US), Israel, Turkey and Russia. Baseline, microbiologic, treatment and outcomes data were collected from patients with hospital-acquired (HABP, n=23) or ventilator-associated bacterial pneumonia (VABP, n=26), bacteremia (n=36), urinary tract infections/acute pyelonephritis (n=16), and wound ABC infections (n=24) between 2017-2019.

Results

Fifty percent of cases reviewed were from the US. The median age of patients was 63 years (range 18-93), 46% were > 65 years old, 69% were male, 31% had renal failure, and 22% had septic shock. The most common co-morbidities observed were cardiac disease (41%), diabetes (32%) and moderate or severe renal disease (26%). Rates of resistance were observed as follows: ciprofloxacin 74%, ceftazidime 67%, amikacin 52% and colistin 0%. Carbapenem resistance (CR) was observed in 49% of patients. Most patients (73%) received combination therapy with 37% receiving at least 4 antibiotics. Carbapenems (40%) and penicillin/b-lactamase inhibitors (42%) were mostly used for treatment. Polymyxins were used in 18% of cases. Overall, the 28-day mortality was 34% and was highest in bacteremia (56%) and VABP (50%). CR appears to be a factor in mortality and other outcomes, as well as hospital days (table). In patients who received monotherapy, all 5 patients with CR infection died compared to 29% mortality in patients with carbapenem sensitive (CS) infection. Mortality was 70% in 20 cases when colistin was used for treatment.

Conclusion

Serious ABC infections are associated with substantial comorbidities and a high mortality rate despite treatment with combination therapy. CR appears to be a major factor in mortality. New antibiotics are urgently needed to treat serious ABC infections.

Disclosures

Khurram Rana, PharmD, Entasis Therapeutics (Employee) Galia Rahav, MD, AstraZeneca (Scientific Research Study Investigator) Kathleen Maloney, CCRP, Entasis Therapeutics (Employee) Subasree Srinivasan, MD MPH, Entasis therapeutics (Employee)

Inverse changes in raphe and cortical 5-HT1B receptor availability after acute tryptophan depletion in healthy human subjects

Serotonergic neurotransmission plays a key role in the pathophysiology and treatment of various neuropsychiatric diseases. The purpose of this study was to investigate changes in serotonergic neurotransmission after acute tryptophan depletion (ATD) using positron emission tomography (PET) with [¹¹ C]P943, a 5-HT_1B receptor radioligand previously shown to be sensitive to changes in 5-HT. Five healthy subjects were scanned on a high resolution PET scanner twice on the same day, before and approximately 5 hours after ingesting capsules containing an amino acid mixture that lacks tryptophan. For each scan, emission data were acquired for 120 min after intravenous bolus injection of [¹¹ C]P943. Binding potential (BP_ND ) values were estimated from parametric images using the second version of the multilinear reference tissue model (MRTM2, t* = 20 min) with cerebellar grey matter used as a reference region. The change in [¹¹ C]P943 binding (ΔBP_ND , %) was calculated as (BP_ND,post  - BP_ND,pre )/(BP_ND,pre ) × 100, and correlation analysis was performed to measure linear associations of ΔBP_ND between raphe and other regions of interest (ROIs). ΔBP_ND ranged from -6% to 45% in the raphe, with positive values indicating reduced competition from 5-HT. In cortical regions, ΔBP_ND ranged from -28% to 7%. While these changes did not reach significance, there were significant negative correlations of ΔBP_ND of the raphe with those of cerebral cortical regions and the thalamus (e.g., r = -.96, p = .011 for average cortex). These findings support the hypothesis that raphe serotonin is a critical modulator of cortical serotonin release via projecting neurons in healthy human subjects.

Education Milestones for Newly Diagnosed Pediatric, Adolescent, and Young Adult Cancer Patients: A Quality Improvement Initiative

The diagnosis of cancer in a child, adolescent, or young adult is an emotionally overwhelming time. To improve the quality of education and support provided to patients and caregivers with a new cancer diagnosis, we executed a quality improvement initiative to (a) define key education milestones for the delivery of essential education during the first 2 months following diagnosis and (b) to define role accountability within the multidisciplinary team for delivery of content and execution of tasks. To develop education milestones, we (a) identified educational content from review of the literature, (b) determined the sequence of content delivery through qualitative interviews with patients and caregivers, and (c) developed education milestones by evaluation of existing workflows. To develop task lists, we (a) determined which multidisciplinary team member was best suited to deliver specific content and (b) defined discrete tasks required to execute education milestones. Key content topics and preferred sequence are as follows: Emotional Adjustment to Diagnosis, When and How to Call the Doctor, Medication Management, Practical Needs, Line Care, and Access to Nontherapeutic Clinical Trials. Eight education milestones were defined across the initial 2 months following cancer diagnosis. The education milestones are paired with task lists. The education milestones and task lists guide the execution of complex education across a multidisciplinary service line in an emotionally challenging time. Early information focuses on essential content, role responsibility is clearly defined, and psychosocial support services are purposefully and iteratively integrated into care during the initial weeks following a cancer diagnosis.

Introducing malaria rapid diagnostic tests in private medicine retail outlets: A systematic literature review

Background

Many patients with malaria-like symptoms seek treatment in private medicine retail outlets (PMR) that distribute malaria medicines but do not traditionally provide diagnostic services, potentially leading to overtreatment with antimalarial drugs. To achieve universal access to prompt parasite-based diagnosis, many malaria-endemic countries are considering scaling up malaria rapid diagnostic tests (RDTs) in these outlets, an intervention that may require legislative changes and major investments in supporting programs and infrastructures. This review identifies studies that introduced malaria RDTs in PMRs and examines study outcomes and success factors to inform scale up decisions.

Methods

Published and unpublished studies that introduced malaria RDTs in PMRs were systematically identified and reviewed. Literature published before November 2016 was searched in six electronic databases, and unpublished studies were identified through personal contacts and stakeholder meetings. Outcomes were extracted from publications or provided by principal investigators.

Results

Six published and six unpublished studies were found. Most studies took place in sub-Saharan Africa and were small-scale pilots of RDT introduction in drug shops or pharmacies. None of the studies assessed large-scale implementation in PMRs. RDT uptake varied widely from 8%-100%. Provision of artemisinin-based combination therapy (ACT) for patients testing positive ranged from 30%-99%, and was more than 85% in five studies. Of those testing negative, provision of antimalarials varied from 2%-83% and was less than 20% in eight studies. Longer provider training, lower RDT retail prices and frequent supervision appeared to have a positive effect on RDT uptake and provider adherence to test results. Performance of RDTs by PMR vendors was generally good, but disposal of medical waste and referral of patients to public facilities were common challenges.

Conclusions

Expanding services of PMRs to include malaria diagnostic services may hold great promise to improve malaria case management and curb overtreatment with antimalarials. However, doing so will require careful planning, investment and additional research to develop and sustain effective training, supervision, waste-management, referral and surveillance programs beyond the public sector.

Expanding access to parasite-based malaria diagnosis through retail drug shops in Tanzania: evidence from a randomized trial and implications for treatment

Background

Tanzania has seen a reduction in the fraction of fevers caused by malaria, likely due in part to scale-up of control measures. While national guidelines require parasite-based diagnosis prior to treatment, it is estimated that more than half of suspected malaria treatment-seeking in Tanzania initiates in the private retail sector, where diagnosis by malaria rapid diagnostic test (RDT) or microscopy is illegal. This pilot study investigated whether the introduction of RDTs into Accredited Drug Dispensing Outlets (ADDOs) under realistic market conditions would improve case management practices.

Methods

Dispensers from ADDOs in two intervention districts in Tanzania were trained to stock and perform RDTs and monitored quarterly. Each district was assigned a different recommended retail price to evaluate the need for a subsidy. Malaria RDT and artemisinin-based combination therapy (ACT) uptake and availability were measured pre-intervention and 1 year post-intervention through structured surveys of ADDO owners and exiting customers in both intervention districts and one contiguous control district. Descriptive analysis and logistic regression were used to compare the three districts and identify predictive variables for testing.

Results and discussion

A total of 310 dispensers from 262 ADDOs were trained to stock and perform RDTs. RDT availability in intervention ADDOs increased from 1% (n = 172) to 73% (n = 163) during the study; ACT medicines were available in 75% of 260 pre-intervention and 68% of 254 post-intervention ADDOs. Pre-treatment testing performed within the ADDO increased from 0 to 65% of suspected malaria patients who visited a shop (95% CI 60.8–69.6%) with no difference between intervention districts. Overall parasite-based diagnosis increased from 19 to 74% in intervention districts and from 3 to 18% in the control district. Prior knowledge of RDT availability (aOR = 1.9, p = 0.03) and RDT experience (aOR = 1.9, p = 0.01) were predictors for testing. Adherence data indicated that 75% of malaria positives received ACT, while 3% of negatives received ACT.

Conclusions

Trained and supervised ADDO dispensers in rural Tanzania performed and sold RDTs under real market conditions to two-thirds of suspected malaria patients during this one-year pilot. These results support the hypothesis that introducing RDTs into regulated private retail sector settings can improve malaria testing and treatment practices without an RDT subsidy.

Trial registration ISRCTN ISRCTN14115509

Introducing rapid diagnostic tests for malaria to drug shops in Uganda: a cluster-randomized controlled trial

Objective

To evaluate the impact – on diagnosis and treatment of malaria – of introducing rapid diagnostic tests to drug shops in eastern Uganda.

Methods

Overall, 2193 households in 79 study villages with at least one licensed drug shop were enrolled and monitored for 12 months. After 3 months of monitoring, drug shop vendors in 67 villages randomly selected for the intervention were offered training in the use of malaria rapid diagnostic tests and – if trained – offered access to such tests at a subsidized price. The remaining 12 study villages served as controls. A difference-in-differences regression model was used to estimate the impact of the intervention.

Findings

Vendors from 92 drug shops successfully completed training and 50 actively stocked and performed the rapid tests. Over 9 months, trained vendors did an average of 146 tests per shop. Households reported 22 697 episodes of febrile illness. The availability of rapid tests at local drug shops significantly increased the probability of any febrile illness being tested for malaria by 23.15% (P = 0.015) and being treated with an antimalarial drug by 8.84% (P = 0.056). The probability that artemisinin combination therapy was bought increased by a statistically insignificant 5.48% (P = 0.574).

Conclusion

In our study area, testing for malaria was increased by training drug shop vendors in the use of rapid tests and providing them access to such tests at a subsidized price. Additional interventions may be needed to achieve a higher coverage of testing and a higher rate of appropriate responses to test results.

Determinants of malaria diagnostic uptake in the retail sector: qualitative analysis from focus groups in Uganda

BACKGROUND

In Uganda, as in most other malaria-endemic countries, presumptive treatment for malaria based on symptoms without a diagnostic blood test is still very common. While diagnostic testing in public sector facilities is increasing, many people in Uganda who suspect malaria visit private sector outlets to purchase medications. Increasing the availability and uptake of rapid diagnostic tests (RDTs) for malaria in private outlets could help increase diagnostic testing for malaria but raises questions about the patient demand for and valuation of testing that are less critical for public sector introduction.

METHODS

In preparation for a behaviour change campaign to encourage and sustain the demand for RDTs in drug shops, eight focus group discussions with a total of 84 community members were conducted in six districts across Uganda's Eastern Region in November-December 2011. Focus groups explored incentives and barriers to seeking diagnosis for malaria, how people react to test results and why, and what can be done to increase the willingness to pay for RDTs.

RESULTS

Overall, participants were very familiar with malaria diagnostic testing and understood its importance, yet when faced with limited financial resources, patients preferred to spend their money on medication and sought testing only when presumptive treatment proved ineffective. While side effects did seem to be a concern, participants did not mention other potential costs of taking unnecessary or ineffective medications, such as money wasted on excess drugs or delays in resolution of symptoms. Very few individuals were familiar with RDTs.

CONCLUSION

In order to boost demand, these results suggest that private sector RDTs will have to be made convenient and affordable and that targeted behaviour change campaigns should strive to increase the perceived value of diagnosis.

Test-retest reliability of the novel 5-HT1B receptor PET radioligand [11C]P943

PURPOSE

[(11)C]P943 is a novel, highly selective 5-HT1B PET radioligand. The aim of this study was to determine the test-retest reliability of [(11)C]P943 using two different modeling methods and to perform a power analysis with each quantification technique.

METHODS

Seven healthy volunteers underwent two PET scans on the same day. Regions of interest (ROIs) were the amygdala, hippocampus, pallidum, putamen, insula, frontal, anterior cingulate, parietal, temporal and occipital cortices, and cerebellum. Two multilinear radioligand quantification techniques were used to estimate binding potential: MA1, using arterial input function data, and the second version of the multilinear reference tissue model analysis (MRTM2), using the cerebellum as the reference region. Between-scan percent variability and intraclass correlation coefficients (ICC) were used to assess test-retest reliability. We also performed power analyses to determine the method that would allow the least number of subjects using within-subject or between-subject study designs. A voxel-wise ICC analysis for MRTM2 BPND was performed for the whole brain and all the ROIs studied.

RESULTS

Mean percent variability between two scans across regions ranged between 0.4 % and 12.4 % for MA1 BPND, 0.5 % and 11.5 % for MA1 BPP, 16.7 % and 28.3 % for MA1 BPF, and between 0.2 % and 5.4 % for MRTM2 BPND. The power analyses showed a greater number of subjects were required using MA1 BPF compared with other outcome measures for both within-subject and between-subject study designs. ICC values were the highest using MRTM2 BPND and the lowest with MA1 BPF in ten ROIs. Small regions and regions with low binding had lower ICC values than large regions and regions with high binding.

CONCLUSION

Reliable measures of 5-HT1B receptor binding can be obtained using the novel PET radioligand [(11)C]P943. Quantification of 5-HT1B receptor binding with MRTM2 BPND and with MA1 BPP provided the least variability and optimal power for within-subject and between-subject designs.

An Improved Antagonist Radiotracer for the κ-Opioid Receptor: Synthesis and Characterization of (11)C-LY2459989

The κ-opioid receptors (KORs) are implicated in several neuropsychiatric diseases and addictive disorders. PET with radioligands provides a means to image the KOR in vivo and investigate its function in health and disease. The purpose of this study was to develop the selective KOR antagonist (11)C-LY2459989 as a PET radioligand and characterize its imaging performance in nonhuman primates.

METHODS

LY2459989 was synthesized and assayed for in vitro binding to opioid receptors. Ex vivo studies in rodents were conducted to assess its potential as a tracer candidate. (11)C-LY2459989 was synthesized by reaction of its iodophenyl precursor with (11)C-cyanide, followed by partial hydrolysis of the resulting (11)C-cyanophenyl intermediate. Imaging experiments with (11)C-LY2459989 were performed in rhesus monkeys with arterial input function measurement. Imaging data were analyzed with kinetic models to derive in vivo binding parameters.

RESULTS

LY2459989 is a full antagonist with high binding affinity and selectivity for KOR (0.18, 7.68, and 91.3 nM, respectively, for κ, μ, and δ receptors). Ex vivo studies in rats indicated LY2459989 as an appropriate tracer candidate with high specific binding signals and confirmed its KOR binding selectivity in vivo. (11)C-LY2459989 was synthesized in high radiochemical purity and good specific activity. In rhesus monkeys, (11)C-LY2459989 displayed a fast rate of peripheral metabolism. Similarly, (11)C-LY2459989 displayed fast uptake kinetics in the brain and an uptake pattern consistent with the distribution of KOR in primates. Pretreatment with naloxone (1 mg/kg, intravenously) resulted in a uniform distribution of radioactivity in the brain. Further, specific binding of (11)C-LY2459989 was dose-dependently reduced by the selective KOR antagonist LY2456302 and the unlabeled LY2459989. Regional binding potential values derived from the multilinear analysis-1 (MA1) method, as a measure of in vivo specific binding signal, were 2.18, 1.39, 1.08, 1.04, 1.03, 0.59, 0.51, and 0.50, respectively, for the globus pallidus, cingulate cortex, insula, caudate, putamen, frontal cortex, temporal cortex, and thalamus.

CONCLUSION

The novel PET radioligand (11)C-LY2459989 displayed favorable pharmacokinetic properties, a specific and KOR-selective binding profile, and high specific binding signals in vivo, thus making it a promising PET imaging agent for KOR.

Non-displaced pediatric orbital fracture with displacement of the inferior rectus muscle into the maxillary sinus: a case report and review of the literature

Orbital fractures occur less frequently in the pediatric population than in the adult population. Due to the elasticity of the bones that comprise the orbital floor it is not uncommon for the orbital floor to fracture and immediately self-reduce. This puts the muscles and soft tissues of the orbital floor at an increased risk of entrapment. There is no exact agreement in the literature as to the ideal timing of surgical intervention for these types of injuries. However, there are many surgeons who advise early intervention in the first few days of the injury. This article describes a case of a non-displaced orbital fracture with displacement of the inferior rectus into the maxillary sinus that was treated in the first 24 h and resulted in an excellent outcome.

Feasibility of distributing rapid diagnostic tests for malaria in the retail sector: evidence from an implementation study in Uganda

BACKGROUND

Despite the benefits of malaria diagnosis, most presumed malaria episodes are never tested. A primary reason is the absence of diagnostic tests in retail establishments, where many patients seek care. Malaria rapid diagnostic tests (RDTs) in drug shops hold promise for guiding appropriate treatment. However, retail providers generally lack awareness of RDTs and training to administer them. Further, unsubsidized RDTs may be unaffordable to patients and unattractive to retailers. This paper reports results from an intervention study testing the feasibility of RDT distribution in Ugandan drug shops.

METHODS AND FINDINGS

92 drug shops in 58 villages were offered subsidized RDTs for sale after completing training. Data on RDT purchases, storage, administration and disposal were collected, and samples were sent for quality testing. Household surveys were conducted to capture treatment outcomes. Estimated daily RDT sales varied substantially across shops, from zero to 8.46 RDTs per days. Overall compliance with storage, treatment and disposal guidelines was excellent. All RDTs (100%) collected from shops passed quality testing. The median price charged for RDTs was 1000USH ($0.40), corresponding to a 100% markup, and the same price as blood slides in local health clinics. RDTs affected treatment decisions. RDT-positive patients were 23 percentage points more likely to buy Artemisinin Combination Therapies (ACTs) (p = .005) and 33.1 percentage points more likely to buy other antimalarials (p<.001) than RDT-negative patients, and were 5.6 percentage points more likely to buy ACTs (p = .05) and 31.4 percentage points more likely to buy other antimalarials (p<.001) than those not tested at all.

CONCLUSIONS

Despite some heterogeneity, shops demonstrated a desire to stock RDTs and use them to guide treatment recommendations. Most shops stored, administered and disposed of RDTs properly and charged mark-ups similar to those charged on common medicines. Results from this study suggest that distributing RDTs through the retail sector is feasible and can reduce inappropriate treatment for suspected malaria.

Increased ratio of anti-apoptotic to pro-apoptotic Bcl2 gene-family members in lithium-responders one month after treatment initiation

Background

Lithium is considered by many as the gold standard medication in the management of bipolar disorder (BD). However, the clinical response to lithium is heterogeneous, and the molecular basis for this difference in response is unknown. In the present study, we sought to determine how the peripheral blood gene expression profiles of patients with bipolar disorder (BD) changed over time following intitiation of treatment with lithium, and whether differences in those profiles over time were related to the clinical response.

Methods

Illumina Sentrix Beadchip (Human-6v2) microarrays containing > 48,000 transcript probes were used to measure levels of expression of gene-expression in peripheral blood from 20 depressed subjects with BD prior to and every two weeks during 8 weeks of open-label treatment with lithium.

Changes in gene-expression were compared between treatment responders (defined as a decrease in the Hamilton Depression Rating Scale of 50% or more) and non-responders. Pathway analysis was conducted using GeneGO Metacore software.

Results

127 genes showed a differential response in responders vs. non-responders. Pathway analysis showed that regulation of apoptosis was the most significantly affected pathway among these genes. Closer examination of the time-course of changes among BCL2 related genes showed that in lithium-responders, one month after starting treatment with lithium, several anti-apoptotic genes including Bcl2 and insulin receptor substrate 2 (IRS2) were up-regulated, while pro-apoptotic genes, including BCL2-antagonist/killer 1 (BAK1) and BCL2-associated agonist of cell death (BAD), were down-regulated. In contrast, in lithium non-responders, BCL2 and IRS2 were down-regulated, while BAK1 and BAD up-regulated at the one-month time-point.

Conclusions

These results suggest that differential changes in the balance of pro- and anti- apoptotic gene-expression following treatment with lithium may explain some of the heterogeneity in clinical response in BD patients.

Abnormal prefrontal activity subserving attentional control of emotion in remitted depressed patients during a working memory task with emotional distracters

BACKGROUND

Patients with major depressive disorder (MDD) show deficits in processing of facial emotions that persist beyond recovery and cessation of treatment. Abnormalities in neural areas supporting attentional control and emotion processing in remitted depressed (rMDD) patients suggests that there may be enduring, trait-like abnormalities in key neural circuits at the interface of cognition and emotion, but this issue has not been studied systematically.

METHOD

Nineteen euthymic, medication-free rMDD patients (mean age 33.6 years; mean duration of illness 34 months) and 20 age- and gender-matched healthy controls (HC; mean age 35.8 years) performed the Emotional Face N-Back (EFNBACK) task, a working memory task with emotional distracter stimuli. We used blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to measure neural activity in the dorsolateral (DLPFC) and ventrolateral prefrontal cortex (VLPFC), orbitofrontal cortex (OFC), ventral striatum and amygdala, using a region of interest (ROI) approach in SPM2.

RESULTS

rMDD patients exhibited significantly greater activity relative to HC in the left DLPFC [Brodmann area (BA) 9/46] in response to negative emotional distracters during high working memory load. By contrast, rMDD patients exhibited significantly lower activity in the right DLPFC and left VLPFC compared to HC in response to positive emotional distracters during high working memory load. These effects occurred during accurate task performance.

CONCLUSIONS

Remitted depressed patients may continue to exhibit attentional biases toward negative emotional information, reflected by greater recruitment of prefrontal regions implicated in attentional control in the context of negative emotional information.

Levetiracetam in the management of bipolar depression: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To study the efficacy of adjunctive levetiracetam therapy compared with placebo in the treatment of subjects with depression with bipolar disorder.

METHOD

This double-blind, placebo-controlled clinical trial randomly assigned outpatients with bipolar disorder type I and type II who were experiencing a major depressive episode (Structured Clinical Interview for DSM-IV Axis I Disorders-Clinician Version criteria) to treatment with either placebo or adjunctive levetiracetam (up to 2,500 mg/d flexibly dosed) for 6 weeks. The subjects were recruited from October 2005 to June 2008. The primary efficacy measure was mean change from baseline to week 6 in the Hamilton Depression Rating Scale (21-item). Secondary efficacy assessments included the Montgomery-Åsberg Depression Rating Scale, the Beck Depression Inventory, the Clinical Global Impressions-Bipolar Version scale, the Hamilton Anxiety Rating Scale, and the Young Mania Rating Scale.

RESULTS

Of 42 subjects randomly assigned to placebo or drug, 32 received at least 1 postbaseline assessment and thus were included in the analysis. The mean (SD) levetiracetam daily dose at endpoint evaluation was 1,132 (425) mg/d. There was no significant difference in the mean change from baseline to week 6 in the Hamilton Depression Rating Scale scores for levetiracetam compared with placebo. There were no significant differences in any of the secondary outcome measures.

CONCLUSIONS

Levetiracetam adjunctive therapy was not superior to placebo in the short-term treatment of subjects with depression with bipolar disorder in the population studied.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00566150.

Increased peripheral blood expression of electron transport chain genes in bipolar depression

OBJECTIVE

  To identify specific genetic pathways showing altered expression in peripheral blood of depressed subjects with bipolar disorder (BPD).

METHODS

  Illumina Sentrix BeadChip (Human-6v2) microarrays containing >48,000 transcript probes were used to measure levels of gene expression in peripheral blood from 20 depressed subjects with BPD and in 15 healthy control subjects. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to confirm a subset of these differences.

RESULTS

  A total of 1,180 genes were differentially expressed between subjects with BPD and healthy controls (fold-change >1.3, false discovery rate-corrected p < 0.05, covaried for age and sex). Of these, 559 genes were up-regulated in BPD subjects and 621 were down-regulated. Surprisingly, there was no difference between medicated (n = 11) and unmedicated (n = 9) subjects with BPD for any of these genes. Pathway analysis using GeneGo MetaCore software showed that the most significantly affected pathway was the mitochondrial electron transport chain (ETC). Of the 85 objects (genes or proteins) in this pathway, 22 were up-regulated and 2 down-regulated in subjects with BPD. qRT-PCR confirmed up-regulation of nuclear encoded ETC genes in complexes I, III, IV, and V and, in addition, demonstrated up-regulation of mitochondrially encoded genes in each of these complexes.

CONCLUSION

  These results suggest that increased expression of multiple components of the mitochondrial ETC may be a primary deficit in bipolar depression, rather than an effect of medication.

TEL-AML1 fusion identifies a subset of children with standard risk acute lymphoblastic leukemia who have an excellent prognosis when treated with therapy that includes a single delayed intensification

The Children's Cancer Group (CCG) found that children with moderate risk acute lymphoblastic leukemia (ALL) had an improved 5-year event-free survival (EFS) rate when treated with therapy that included a doubled delayed intensification (DDI) vs a single DI (SDI) phase. Because of increased toxicity with DDI, it is important to determine whether subgroups of children with ALL can be identified who have excellent outcomes with SDI therapy. TEL-AML1 fusion and hyperdiploid DNA content are present in the leukemic blasts of significant proportions of children with ALL and have been associated with an excellent prognosis. In this study, we retrospectively examined the impact of TEL-AML1 status and ploidy on treatment outcome in a cohort of 75 children with standard risk ALL treated at our institution between 1983 and 1993 with SDI therapy. TEL-AML1 fusion was present in 19/43 (44%) evaluable cases. Fifteen of 56 (27%) evaluable cases were classified as hyperdiploid based on a modal chromosome number of >/=51 and/or a DNA index of >/=1.16. The 7-year EFS was 81% for the 19 TEL-AML1-positive patients vs 54% for the 24 TEL-AML1-negative patients (P = 0.0264). In multivariate analyses, TEL-AML1-positive status was associated with a superior EFS (P = 0.02) even when the intial white blood count was included in the model. Overall survival (OS) at 7 years for TEL-AML1-positive patients was 100% vs 83% for TEL-AML1-negative patients (P = 0.0677). There were no differences in 7-year EFS or OS based on ploidy comparisons. These results underscore the need to examine closely the effects of treatment intensification on specific biologically defined subgroups of children with ALL.

An overview of outcomes research and measurement

Rapidly rising healthcare costs, questions about effective medical intervention, and the need for efficient delivery of healthcare services have compelled organizations to focus on outcomes research, measurement, and management. Proponents of outcomes measurement predict that it will produce significant benefits, including improved physician and patient information, increased understanding of the effectiveness of different treatment interventions, and established guidelines for medical management. Multiple professional organizations, academic centers, and independent research laboratories, as well as government agencies, are now involved in the research and development of outcomes measurement tools. This article provides some insight into the outcomes phenomenon.

The clinical display of radiologic information as an interactive multimedia report

We regard the delivery of radiological information as an interactive multimedia report. We use a multimedia report model based on Extensible Markup Language (XML), rather than a traditional workstation model. Others have suggested a similar document-based approach. This display presentation includes image-related and text-based information and may contain interactive components (e.g., window, level and zoom). Using XML as a foundation for this multimedia presentation, we achieve flexibility and platform independence at a lower cost. XML allows for the separation of content and form. Content information, defined as elements (e.g., images, radiologic reports, and demographic information), is treated as independent information objects. The behavior of the elements can be changed for different users and tasks. In addition, by separating format detail from content, the appearance of the elements within the report can be modified. XML does not replace existing standards (i.e., Digital Imaging and Communications in Medicine [DICOM], Transmission Control Protocol/Internet Protocol [TCP/IP]). Instead, it provides a powerful framework that is used in combination with existing standards to allow system designers to modify display characteristics based on user need. We describe our application of XML to the clinical display of radiologic information.

Diarrhoea prevention in Bolivia through point-of-use water treatment and safe storage: a promising new strategy

A novel water quality intervention that consists of point-of-use water disinfection, safe storage and community education was field tested in Bolivia. A total of 127 households in two periurban communities were randomized into intervention and control groups, surveyed and the intervention was distributed. Monthly water quality testing and weekly diarrhoea surveillance were conducted. Over a 5-month period, intervention households had 44% fewer diarrhoea episodes than control households (P = 0.002). Infants < 1 year old (P = 0.05) and children 5-14 years old (P = 0.01) in intervention households had significantly less diarrhoea than control children. Campylobacter was less commonly isolated from intervention than control patients (P = 0.02). Stored water in intervention households was less contaminated with Escherichia coli than stored water in control households (P < 0.0001). Intervention households exhibited less E. coli contamination of stored water and less diarrhoea than control households. This promising new strategy may have broad applicability for waterborne disease prevention.

Consequences in Georgia of a nationwide outbreak of Salmonella infections: what you don't know might hurt you

OBJECTIVES

This study assessed the impact in Georgia of a nationwide salmonellosis outbreak caused by ice cream products and the effectiveness of the subsequent warning against eating the implicated products.

METHODS

A telephone survey of 250 randomly selected Georgia customers of the ice cream producer was conducted 13 to 17 days after the warning.

RESULTS

Respondents from 179 households representing 628 persons were interviewed. The median date of first hearing the warning was 5 days after it was issued, and 16 respondents (9%) had not heard it. Among those who had heard the warning, 42 (26%) did not initially believe the products were unsafe. In 22 (31%) of the 72 households that had the implicated ice cream when the respondent heard the warning, someone subsequently ate the ice cream. Diarrhea was reported in 26% (121/463) of persons who had eaten the products but in only 5% (8/152) who had not (odds ratio [controlling for household clustering] = 3.8; 95% confidence interval = 2.0, 7.5). We estimate this outbreak caused 11,000 cases of diarrhea in Georgia, 1760 (16%) with exposure after the warning.

CONCLUSIONS

A large outbreak occurred in Georgia, much of which might have been prevented by a more timely and convincing warning.

A nationwide case-control study of Escherichia coli O157:H7 infection in the United States

Risk factors for Escherichia coli O157:H7 infection were investigated in a case-control study at 10 medical centers throughout the United States. Among 73 case-patients and 142 matched controls, exposures in the 7 days before illness associated with E. coli O157:H7 infection in univariate analysis included consumption of hamburger (matched odds ratio [MOR], 3.8; 95% confidence interval [CI], 1.9-7.9), undercooked hamburger (MOR, 4.5; 95% CI, 1.6-12.2), or hot dogs (MOR, 2.2; 95% CI, 1.1-4.4); eating at a fast-food restaurant (MOR, 2.3; 95% CI, 1.1-4.6); drinking unchlorinated well water (MOR, 2.4; 95% CI, 1.1-5.7); swimming in a pond (MOR, 5.4; 95% CI, 1.1-26.0); and having a household member with diarrhea (MOR, 11.9; 95% CI, 2.7-53.5). In multivariate analysis, only eating undercooked hamburger remained associated with infection. Seven (8%) of 93 patients developed hemolytic uremic syndrome and 1 died. Prevention strategies aimed at modifying risk factors may help to reduce the risk of infection with E. coli O157:H7.

Evaluation of radiologist performance using telemedicine services

Observer performance of radiologists using a telemedicine service was evaluated. Diagnoses between the rural and consulting radiologists agreed 84% of the time. The main reason for disagreement was extent of lesion rather than type or absence/presence. Consulting times and image quality were considered adequate.

Improving access to knowledge-based health sciences information: early results from a statewide collaborative effort

Access to biomedical literature has been shown to reduce the patient's length of stay and thus reduce the cost of the hospital visit. Unfortunately, access to the most current information, at the time and place of need, requires a substantial commitment of resources in the form of staff expertise, computer hardware and software, and user training. The cost of these resources may be prohibitively high for all but the largest institutions. The Arizona Health Information Network (AZHIN) brings together librarians, information systems specialists, and health care professionals from hospitals throughout the state in an effort to share resources and expertise. By reducing the cost of access, AZHIN has increased the availability of health-related information across the state. Progress in AZHIN's first two years is described.

The renal axes in spina bifida: issues of confusion and fusion

The occurrence of horseshoe kidneys in myelodysplasia has been suggested to be overestimated because of the concurrent prevalence of kyphotic spine in the spina bifida population. Pseudohorseshoe kidneys result from the actual medial migration and apposition of the lower renal poles in the deep fossa created by the gibbus deformity. The presence of a lumbosacral kyphosis, however, does not imply there is not a true horseshoe kidney. In our myelodysplasia population of 189 patients, occurrence of true horseshoe kidneys (13 patients) and pseudohorseshoe kidneys (14 patients) was increased. The finding of lumbosacral kyphosis was twice as common in the pseudohorseshoe population as in the true horseshoe population. True horseshoe kidneys were three times more commonly seen in association with congenital vertebral anomalies cephalad to the dysraphic spine. Diagnosis in this study was predominantly based on renal cortical scintigraphy with the posterior pin-hole magnification technique.

Mortality from intentional and unintentional injury among infants of young mothers in Colorado, 1986 to 1992

OBJECTIVES

To investigate the association between maternal age and other risk factors and infant injury deaths in the state of Colorado from 1986 to 1992.

DESIGN

A retrospective cohort design was used to compare rates of unintentional and intentional infant injury mortality by maternal age group. A case-control design explored the importance of various risk factors, particularly maternal age, using multivariate logistic regression.

PARTICIPANTS

The 2 case groups comprised all unintentional and intentional injury deaths in the first year of life. The control group was a random sample of both survivors and noninjury deaths selected from the entire birth cohort.

RESULTS

The infant injury mortality rate for the 322766 live births in Colorado from 1986 to 1992 was 3.1 per 10000. Intentional injury death rates were highest for infants of teenaged mothers, peaking at 10.5 per 10000 live births for mothers aged 16 years. Unintentional injury death rates were highest for infants of mothers aged 20 to 24 years, peaking at 3.7 per 10000 live births for 22-year-old mothers. For intentional injury death, maternal marital status had a significant impact on maternal age; compared with the baseline group of married mothers older than 24 years, significantly higher risks were observed for infants of teenagers who were married (odds ratio [OR] = 32.0; 95% confidence interval[CI], 9.9-104.0) but also in infants of older mothers who were unmarried (OR = 3.6; 95% CI, 1.0-13.0 for unmarried mothers aged 20-24 years and (OR = 7.7; 95% CI, 2.4-25.0 for those > 24 years). Black race (OR = 3.5; 95% CI, 1.4-9.4) was also associated with intentional injury death. For unintentional injury death, the highest risk was for infants of mothers aged 20 to 24 years and unmarried (OR = 3.9; 95% CI, 1.7-9.3). Risk was also elevated for infants of married teenaged mothers (OR = 3.5; 95% CI, 0.7-17.8) but was not significantly different from the baseline group for unmarried teenagers, married 20- to 24-year-old mothers, or unmarried mothers aged 25 years or older. Risk was increased by the presence of older siblings (OR = 1.5 per sibling; 95% CI, 1.2-2.0).

CONCLUSIONS

Maternal age and marital status significantly affect the rate of both unintentional and intentional infant injury mortality. These results suggest that child abuse prevention strategies should be targeted to teenaged mothers, and that strategies designed to prevent unintentional injuries should focus particularly on parents or caretakers of infants born to unmarried mothers in their early 20s as well as married teenagers.

Fluorescence signaling of ligand binding and assembly in metal-chelating lipid membranes

BACKGROUND

Chemical information is sometimes transmitted across cell membranes by ligand-induced assembly of receptors. We have previously designed a series of lipids with metal-chelating headgroups that can serve as general receptors for proteins containing accessible histidines. Such lipids can also be derivatized with pyrene, a fluorescent probe that has a different emission maximum when it is aggregated (excimer fluorescence) from that seen for the monomer. We set out to examine whether lipids of this kind would produce a signal in response to ligand binding.

RESULTS

A model ligand, poly-L-histidine (poly(His)), bound specifically to pyrene-labeled Cu(II)-iminodiacetate lipid (Cu-PSIDA) within a membrane matrix. Binding of poly(His) induces the redistribution of Cu-PSIDA, so that it forms pyrene-rich domains that are detectable by the increased ratio of excimer to monomer fluorescence. Using rhodamine-labeled poly(His), we have shown that the receptor lipid domains correspond to poly(His)-rich domains below the lipid interface.

CONCLUSIONS

The Cu-PSIDA receptor signals binding of the macromolecular ligand through its excimer fluorescence and allows the resulting domains formed by ligand assembly to be imaged. Fluorescent Cu-PSIDA can thus serve as an optical reporter of ligand-induced lipid reorganization.

Epidemiology of diarrheal disease outbreaks on cruise ships, 1986 through 1993

OBJECTIVE

To describe the epidemiology of cruise-associated diarrheal disease outbreaks from 1986 through 1993, to determine if the incidence had changed since 1985, and to determine the preventability of outbreaks that continue to occur.

DESIGN

The numerator data were collated from Centers for Disease Control and Prevention (CDC) outbreak investigation reports from 1986 through 1993. The denominator data were summations of cruise ship data on the number of passengers and length of cruises collected during routine diarrheal illness surveillance, available only for the period 1989 through 1993.

SETTINGS

Cruise ships with outbreaks of diarrheal disease.

PARTICIPANTS

Cruise ship passengers and crew of staff ho participated in the original investigations.

MAIN OUTCOME MEASURES

The incidence of outbreaks during the study period, pathogens isolated, and vehicles of transmission implicated in investigations.

RESULTS

Among cruises of 3 to 15 days, CDC staff investigated 1.4 outbreaks per 1000 cruises, or 2.3 outbreaks per 10 million passenger-days. An etiologic agent was implicated in 21 (68%) of 31 investigated outbreaks: bacterial in 12, viral in nine. A specific vehicle of transmission was identified in 16. The most common vehicles of transmission were undercooked scallops (three outbreaks caused by enterotoxigenic Escherichia coli), eggs (two outbreaks caused by Salmonella serotype Enteritidis, one by Norwalk-like virus), and food items provided by caterers during onshore excursions (three outbreaks, one caused by Shigella sonnei).

CONCLUSIONS

Observance of two simple precautions could have prevented almost one third (5/16, or 31%) of the investigated outbreaks on cruise ships. Cruise lines have been reminded to cook seafoods thoroughly and to use pasteurized eggs for menu items calling for pooled eggs. Preventing food handlers from working while ill and not using onshore caterers for offship excursions might have prevented at least an additional one third (5/16) of these outbreaks.

Plasma inorganic fluoride concentrations after sevoflurane anesthesia in children

BACKGROUND

Sevoflurane is degraded in vivo in adults yielding plasma concentrations of inorganic fluoride [F-] that, in some patients, approach or exceed the 50- micron theoretical threshold for nephrotoxicity. To determine whether the plasma concentration of inorganic fluoride [F-] after 1-5 MAC x h sevoflurane approaches a similar concentration in children, the following study in 120 children scheduled for elective surgery was undertaken.

METHODS

Children were randomly assigned to one of three treatment groups before induction of anesthesia: group 1 received sevoflurane in air/oxygen 30% (n = 40), group 2 received sevoflurane in 70% N2O/30% O2 (n = 40), and group 3 received halothane in 70% N2O/30% O2 (n = 40). Mapleson D or F circuits with fresh gas flows between 3 and 61/min were used Whole blood was collected at induction and termination of anesthesia and at 1, 4, 6, 12, and 18 or 24 h postoperatively for determination of the [F-]. Plasma urea and creatinine concentrations were determined at induction of anesthesia and 18 or 24 h postoperatively.

RESULTS

The mean (+/- SD) duration of sevoflurane anesthesia, 2.7 +/- 1.6 MAC x h (range 1.1-8.9 MAC x h), was similar to that of halothane, 2.5 +/- 1.1 MAC x h. The peak [F-] after sevoflurane was recorded at 1 h after termination of the anesthetic in all but three children (whose peak values were recorded between 4 and 6 h postanesthesia). The mean peak [F-] after sevoflurane was 15.8 +/- 4.6 microns. The [F-] decreased to <6.2 microns b 24 h postanesthesia. Both the peak [F-] (r2 = 0.50) and the area under the plasma concentration of inorganic fluoride-time curve (r2 = 0.57) increased in parallel with the MAC x h of sevoflurane. The peak [F-] after halothane, 2.0 +/- 1.2 microns, was significantly less than that after sevoflurane (P<0.00012) and did not correlate with the duration of halothane anesthesia (MAC x h; r2 = 0.007). Plasma urea concentrations decreased 24 h after surgery compared with preoperative values for both anesthetics (P<0.01), whereas plasma creatinine concentrations did not change significantly with either anesthetic.

CONCLUSIONS

It was concluded that, during the 24 h after 2.7 +/- 1.6 MAC x h sevoflurane, the peak recorded [F-] is low (15.8 microns), F- is eliminated rapidly, and children are unlikely to be at risk of nephrotoxicity from high [F-].

Effect of antiemetic therapy on recovery and hospital discharge time. A double-blind assessment of ondansetron, droperidol, and placebo in pediatric patients undergoing ambulatory surgery

BACKGROUND

Postoperative nausea and vomiting continue to be a significant problem for pediatric ambulatory surgery patients. Although ondansetron has been demonstrated to be effective in the prophylactic treatment of postoperative nausea and vomiting (surrogate end point) no one has demonstrated a benefit of antiemetic therapy on patient recovery, postanesthesia care unit length of stay, and hospital length of stay (nonsurrogate end points). In a double-blind manner, the effects of ondansetron, droperidol, and placebo on the incidence of emesis, postanesthesia care unit stay, and hospital discharge time were evaluated in children undergoing dental surgery.

METHODS

The subjects were 102 children aged 2-8 years undergoing complete dental restoration. All patients received midazolam before undergoing inhalation induction of anesthesia with N2O/O2 and halothane. Anesthesia was maintained with N2O/O2 and alfentanil. Patients were then randomized to receive ondansetron (0.1 mg/kg), droperidol (75 micrograms/kg), or placebo (normal saline) in a double-blind fashion. At the conclusion of the anesthesia, a trained nurse observer assessed patient recovery and recorded the time patients met specified criteria for postanesthesia care unit and hospital discharge as well as episodes of emesis in the hospital and at home during the first 24 hr after surgery.

RESULTS

Ninety-five patients completed the study. The three antiemetic groups were similar with respect to age, weight, length of surgery, dose of alfentanil, and route of preanesthetic medication. The 24-hr incidence of emesis was significantly less with ondansetron (9%) than with placebo (35%) or droperidol (32%). Ondansetron-treated patients had significantly shorter hospital stays than droperidol-treated patients, but recovery parameters were similar between the ondansetron- and placebo-treated patients.

CONCLUSIONS

Ondansetron is an effective prophylactic antiemetic agent for children undergoing dental surgery. Compared with droperidol, ondansetron decreases the length of hospital stay, but compared to placebo, there were no differences in the patient recovery parameters.

Receiver operating characteristic evaluation of computer display of adult portable chest radiographs

RATIONALE AND OBJECTIVES

The suitability of using an image console monitor for interpretation of adult portable chest radiographs was evaluated with receiver operating characteristic (ROC) analysis and subjective techniques.

METHODS

Radiologists read 80 chest images, once on a display monitor and once on computed radiography film, for the presence or absence of pneumothorax or atelectasis. Judgments of correct or incorrect positions of tubes and lines were reported, and total viewing time was recorded.

RESULTS

A statistically significant difference was found in favor of monitor reading for detection of pneumothoraces. Atelectasis detection also was higher with monitor reading, but the difference did not reach statistical significance. Tube/line judgments were equivalent for both modes. Total viewing time was approximately 1 minute longer per image with the monitor.

CONCLUSIONS

Viewing computed radiography images on a workstation monitor does not seem to affect diagnostic accuracy compared with film viewing. Preset image defaults tailored to the individual radiologist could decrease total viewing time to acceptable levels.

Introduction of a composite parameter to the pharmacokinetics of venlafaxine and its active O-desmethyl metabolite

Venlafaxine is a structurally novel, nontricyclic compound that is being evaluated for the treatment of various depressive disorders. A randomized three-period crossover study was conducted to obtain pharmacokinetic and dose proportionality data on the drug and its active metabolite, O-desmethylvenlafaxine. Eighteen healthy young men received single doses of venlafaxine 25, 75, and 150 mg followed by 3 days of administration every 8 hours (q8h). Steady-state elimination half-life was 3 to 4 hours for venlafaxine and 10 hours for O-desmethylvenlafaxine; both were independent of dose. Venlafaxine had a high oral-dose clearance, ranging from 0.58 to 2.63 L/hr/kg across doses with the lowest mean clearance, 0.98 L/hr/kg, at the highest dose. The apparent clearance of O-desmethylvenlafaxine was lower than venlafaxine, ranging from 0.21 to 0.66 L/hr/kg, and the lowest mean clearance, 0.33 L/hr/kg, occurred at the lowest dose. The area under the metabolite curve was two to three times greater than that for venlafaxine. Each compound had linear dose proportionality up to 75 mg q8h. A composite parameter incorporating venlafaxine plus O-desmethylvenlafaxine was introduced (i.e., AUC [area under the curve] + activity factor.AUCm), which extended linearity to 150 mg q8h. In summary, venlafaxine is a high-clearance drug that forms a metabolite with almost equal activity and demonstrates linear dose-proportionality.

Efficacy of digital radiography for the detection of pneumothorax: comparison with conventional chest radiography

As part of our continuing evaluation of the clinical applicability of digital radiography, we compared the abilities of radiologists to detect pneumothoraces on conventional chest radiographs with their performances when using three formats of digitally obtained images. Twenty-three frontal-view chest radiographs with pneumothoraces and 22 other chest radiographs, either normal or showing miscellaneous abnormalities, were interpreted by five experienced radiologists in each of four formats: conventional film-screen chest radiographs, small-format (17.8 x 21.6 cm) computed radiographs, large-format (35.6 x 43.1 cm) computed radiographs, and digital images viewed on an interactive electronic workstation. The receiver-operating-characteristic curve areas for each observer for the four types of images were compared by a z test on a critical ratio, and the mean sensitivity and specificity values were compared by the sign rank test. The mean areas under the receiver-operating-characteristic curves ranged from 0.869 for the digital workstation to 0.915 for film-screen images. The differences observed among formats were not statistically significant. Mean specificities also were not significantly different, ranging from 0.90 for large-format computed radiographs to 0.96 for the digital workstation. Mean sensitivity ranged from 0.65 for the digital workstation to 0.82 for film-screen images. Radiologists interpreting digital workstation images were significantly less sensitive in detecting pneumothoraces than with film-screen and small-format computed images (p = .06). In this study, radiologists detected pneumothoraces equally well on conventional film-screen radiographs and digital images printed on film; however, they detected pneumothoraces less well on electronic viewing consoles. This latter finding reflects an important practical difference in the working behavior of radiologists interacting with a digital workstation.

A novel mouse model to study the virulence of and host response to Porphyromonas (Bacteroides) gingivalis

We describe here the development of a mouse subcutaneous chamber model that allows for the examination of host-parasite interactions as well as the determination of gross pathology with Porphyromonas (Bacteroides) gingivalis challenge. When inoculated into stainless-steel chambers implanted subcutaneously in female BALB/c mice, P. gingivalis W83, W50, and A7436 (10(8) to 10(10) CFU) caused cachexia, ruffling, general erythema and phlegmonous, ulcerated, necrotic lesions, and death. P. gingivalis W50/BEI, HG405, and 33277 (10(10) CFU) produced localized abscesses in the mouse chamber model with rejection of chambers at the injection site. Analysis of chamber fluid from 33277-, HG405-, and W50/BEI-infected mice by cytocentrifugation revealed inflammatory cell debris, polymorphonuclear leukocytes, and high numbers of dead bacteria. In contrast, fluid from A7436-, W50-, and W83-infected mice revealed infiltration predominantly of polymorphonuclear leukocytes and live bacteria. Bacteria were found primarily associated with polymorphonuclear leukocytes in the fluid from W50-, HG405-, and W83-infected mice but not from A7436-infected mice. Viable isolates were recoverable from the chamber fluid through day 3 for W50/BEI, day 5 for 33277, day 6 for HG405, day 7 for W50, day 14 for W83, and day 26 for A7436. All strains induced a systemic immunoglobulin G response in serum and chamber fluid samples. The use of this model will allow us to examine the virulence of P. gingivalis as defined by the interaction of host response to localized infection with P. gingivalis.

Evaluation of the ACR-NEMA standard for communications in digital radiology

An implementation and evaluation of a prototype multivendor communications system which complies with the American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA) standard for communications in digital radiology is discussed. The system allows communications between interfaces from different manufacturers within a networked environment. The implementation includes network software compatible with the International Standards Organization's Open Systems Interconnect standard. The experience of the implementation effort and the evaluation of the system provide the basis for a critique of the ACR-NEMA standard. It is concluded that the ACR-NEMA standard is not well suited for application to the networked environment of picture archiving and communications systems. Two possible solutions are recommended for this problem. The first is a major revision of the existing standard. The second is the development of a family of network communications standards for digital radiology.

Bloom syndrome: a single complementation group defines patients of diverse ethnic origin

Patients of diverse ethnic background were recruited in order to examine whether genetic heterogeneity could be demonstrated in Bloom syndrome (BS). Although most cells from BS patients exhibit high sister-chromatid exchange (SCE), lymphoid cells from some patients exhibit dimorphism for high and low SCE. We addressed the issue of dominance or recessivity of the low-SCE BS phenotype. A high-SCE lymphoblast line, HB1, was mutagenized, and a clone, HB10T, carrying the markers ouabain resistance and thioguanine resistance, was isolated to serve as a fusion parent. Two independent low-SCE BS lines were fused with HB10T, and hybrids were selected in HAT medium supplemented with ouabain. The hybrids, which were tetraploid, exhibited the expected phenotypes when exposed to ouabain and thioguanine. In every case, these hybrids had low SCE levels, establishing dominance of the low-SCE phenotype. The same methodology was also used to assess genetic heterogeneity in BS. A complementation analysis was carried out using high-SCE lymphoblast cell lines derived from BS patients. HB10T was fused with five other high-SCE BS lines. No correction of the high SCE characteristic of BS cells was seen in hybrid lines derived from patients of Ashkenazi Jewish, French-Canadian, Mennonite, or Japanese extraction. Thus, a single gene is responsible for the high-SCE phenotype in BS patients of diverse ethnic origin.

Pharmacokinetics of quinidine and three of its metabolites in man

Disposition parameters of quinidine and three of its metabolism, 3-hydroxy quinidine, quinidine N-oxide, and quinidine 10,11-dihydrodiol, were determined in five normal healthy volunteers after prolonged intravenous infusion and multiple oral doses. The plasma concentrations of individual metabolites after 7 hr of constant quinidine infusion at a plasma quinidine level of 2.9 +/- (SD) 0.3 mg/L were: 3-hydroxy quinidine, 0.32 +/- 0.06 mg/L; quinidine N-oxide, 0.28 +/- 0.03 mg/L; and quinidine 10,11-dihydrodiol, 0.13 +/- 0.04 mg/L. Plasma trough levels after 12 oral doses of quinidine sulfate every 4 hr averaged: quinidine, 2.89 +/- 0.50 mg/L; 3-hydroxy quinidine, 0.83 +/- 0.36 mg/L; quinidine N-oxide, 0.40 +/- 0.13 mg/L; and quinidine 10,11-dihydrodiol, 0.38 +/- 0.08 mg/L. Relatively higher plasma concentrations of 3-hydroxy quinidine metabolite after oral dosing probably reflect first-pass formation of this quinidine metabolite. A two-compartment model for quinidine and a one-compartment model for each of the metabolites described the plasma concentration-time curves for both i.v. infusion and multiple oral doses. Mean (+/- SD) disposition parameters for quinidine from individual fits, after i.v. infusion were as follows: Vl, 0.37 +/- 0.09 L/kg; lambda 1, 0.094 +/- 0.009 min-1; lambda 2, 0.0015 +/- 0.0002 min-1; EX2, 0.013 +/- 0.002 min-1; clearance (ClQ), 3.86 +/- 0.83 ml/min/kg. Both plasma and urinary data were used to determine metabolic disposition parameters. Mean (+/- SD) values for the metabolites after i.v. quinidine infusion were as follows: 3-hydroxy quinidine: formation rate constant kmf, 0.0012 +/- 0.0005 min-1, volume of distribution, Vm, 0.99 +/- 0.47 L/kg; and elimination rate constant, kmu 0.0030 +/- 0.0002 min-1. Quinidine N-oxide: kmf, 0.00012 +/- 0.00003 min-1; Vm, 0.068 +/- 0.020 L/kg; and kmu, 0.0063 +/- 0.0008 min-1. Quinidine 10,11-dihydrodiol: kmf, 0.0003 +/- 0.0001 min-1; Vm, 0.43 +/- 0.29 L/kg; and kmu, 0.0059 +/- 0.0010 min-1. Oral absorption of quinidine was described by a zero order process with a bioavailability of 0.78. Concentration dependent renal elimination of 3-hydroxy quinidine was observed in two out of five subjects studied.

Endocrine profile in a patient with familial breast cancer: a case-control study

Urinary and blood hormonal profiles were studied throughout a monthly cycle in a patient with familial breast cancer. Two comparison cohorts (one high-risk and one low-risk) were studied concurrently. Findings disclosed that our breast cancer-affected patient showed a distinctive hormonal pattern characterized by significant elevation throughout the cycle of plasma estrone, estradiol, and prolactin. Save for a depression in plasma FSH in the early follicular phase, this hormone, as wells as LH and progesterone patterns in our patient, were similar to the comparison cohorts. Urinary estrone and estradiol patterns in our patient were elevated early in the follicular phase. Our patient also showed a depression in urinary estrone, estradiol, and estriol following ovulation, which persisted throughout the luteal phase. Blood and urinary hormone patterns in the high-risk cohort were not demonstrably different from the low-risk cohort, with the exception of plasma prolactin. The results on the latter hormone showed an unexpected significant depression throughout most of the menstrual cycle in this low-risk cohort. We conclude that estrone and estradiol elevations, as clearly evidenced in our breast-cancer-affected patient, may provide clues that ultimately might be used as an etiologic discriminant for breast cancer risk and which may also play a pathogenic role in this disease. Since this involved a single patient, our conclusions must be interpreted cautiously.

Plasma hormone profiles of young women at risk for familial breast cancer

The plasma hormone concentrations of 30 young women, who were judged by genetic analysis to be at high risk for familial breast cancer, were compared with those of 30 matched controls identified as at low risk for the disease. The hormone measurements were obtained every second day throughout the menstrual cycle, and the results were analyzed in terms of follicular, luteal, and full-cycle mean concentrations. Comparison was carried out in a paired fashion with each high-risk and low-risk pair matched closely for height, weight, age, and reproductive history. No statistically significant differences were found in prolactin, gonadotropin, estrone, estradiol, or estriol plasma concentrations although the high-risk group displayed consistently lower values in all of the above except estriol.