Building FAIR Functionality: Annotating Events in Time Series Data Using Hierarchical Event Descriptors (HED)

Human electrophysiological and related time series data are often acquired in complex, event-rich environments. However, the resulting recorded brain or other dynamics are often interpreted in relation to more sparsely recorded or subsequently-noted events. Currently a substantial gap exists between the level of event description required by current digital data archiving standards and the level of annotation required for successful analysis of event-related data across studies, environments, and laboratories. Manifold challenges must be addressed, most prominently ontological clarity, vocabulary extensibility, annotation tool availability, and overall usability, to allow and promote sharing of data with an effective level of descriptive detail for labeled events. Motivating data authors to perform the work needed to adequately annotate their data is a key challenge. This paper describes new developments in the Hierarchical Event Descriptor (HED) system for addressing these issues. We recap the evolution of HED and its acceptance by the Brain Imaging Data Structure (BIDS) movement, describe the recent release of HED-3G, a third generation HED tools and design framework, and discuss directions for future development. Given consistent, sufficiently detailed, tool-enabled, field-relevant annotation of the nature of recorded events, prospects are bright for large-scale analysis and modeling of aggregated time series data, both in behavioral and brain imaging sciences and beyond.

Capturing the nature of events and event context using hierarchical event descriptors (HED)

Event-related data analysis plays a central role in EEG and MEG (MEEG) and other neuroimaging modalities including fMRI. Choices about which events to report and how to annotate their full natures significantly influence the value, reliability, and reproducibility of neuroimaging datasets for further analysis and meta- or mega-analysis. A powerful annotation strategy using the new third-generation formulation of the Hierarchical Event Descriptors (HED) framework and tools (hedtags.org) combines robust event description with details of experiment design and metadata in a human-readable as well as machine-actionable form, making event annotation relevant to the full range of neuroimaging and other time series data. This paper considers the event design and annotation process using as a case study the well-known multi-subject, multimodal dataset of Wakeman and Henson made available by its authors as a Brain Imaging Data Structure (BIDS) dataset (bids.neuroimaging.io). We propose a set of best practices and guidelines for event annotation integrated in a natural way into the BIDS metadata file architecture, examine the impact of event design decisions, and provide a working example of organizing events in MEEG and other neuroimaging data. We demonstrate how annotations using HED can document events occurring during neuroimaging experiments as well as their interrelationships, providing machine-actionable annotation enabling automated within- and across-experiment analysis and comparisons. We discuss the evolution of HED software tools and have made available an accompanying HED-annotated BIDS-formated edition of the MEEG data of the Wakeman and Henson dataset (openneuro.org, ds003645).

Replication of Marek's disease vaccines in turkey embryos and their effect on TLR-3 and IFN-γ transcripts

Understanding the pathogenesis of herpesvirus of turkeys (HVT) in its natural host is necessary before recombinant HVT (rHVT) can be used efficiently in turkey flocks. The objectives of this study were to evaluate when commercial turkey flocks get infected with wild type HVT, to study replication of HVT (conventional and recombinant rHVT-Newcastle disease, rHVT-ND) and other Marek's disease (MD) vaccines (SB-1 and CVI988) in turkey embryonic tissues, and to evaluate the expression of TLR-3 and IFN-γ in the lung and spleen of one-day-old turkeys after in ovo vaccination with MD vaccines. Our results demonstrated that commercial turkeys got exposed to wild type HVT within the first days of life; therefore, there is a potential of interaction between wild type HVT and rHVT when administered at day of age. On the other hand, all evaluated vaccines (especially HVT and rHVT-ND) replicated very well in turkey embryonic tissues. In ovo vaccination with HVT and CVI988 increased transcription of TLR-3 in the spleen of one-day-old turkeys. However, no effect on the transcription of TLR-3 or IFN-γ in the lungs and IFN-γ in the spleen in newly hatched turkeys was detected in the present study. Because of the limitations of evaluated genes, timepoints, and studied tissues, future studies are warranted to better understand the effect of MD vaccines on the turkey embryo immune responses.RESEARCH HIGHLIGHTS Commercial turkey flocks get infected with wild type HVT within the first days of life.HVT and rHVT replicates readily in turkey embryonic tissues.SB-1 and CVI988 also replicate in turkey embryonic tissues, but at lower rates than HVT and rHVT.HVT and CVI988 increase transcription of TLR-3 in the spleen.

Spindler: a framework for parametric analysis and detection of spindles in EEG with application to sleep spindles

OBJECTIVE

EEG spindles, narrow-band oscillatory signal bursts, are widely-studied biomarkers of subject state and neurological function. Most existing methods for spindle detection select algorithm parameters by optimizing agreement with expert labels. We propose a new framework for selecting algorithm parameters based on stability of spindle properties and elucidate the dependence of these properties on parameter selection for several algorithms.

APPROACH

To demonstrate this approach we developed a new algorithm (Spindler) that decomposes the signal using matching pursuit with Gabor atoms and computes the spindles for each point in a fine grid of parameter values. After computing characteristic surfaces as a function of parameters, Spindler selects algorithm parameters based on the stability of characteristic surface geometry.

MAIN RESULTS

Spindler performs well relative to several common supervised and unsupervised EEG sleep spindle detection methods. Spindler is available as an open-source MATLAB toolbox (https://github.com/VisLab/EEG-Spindles). In addition to Spindler, the toolbox provides implementations of several other spindle detection algorithms as well as standardized methods for matching ground truth to predictions and a framework for understanding algorithm parameter surfaces.

SIGNIFICANCE

This work demonstrates that parameter selection based on physical constraints rather than labelled data can provide effective, fully-automated, unsupervised spindle detection. This work also exposes the dangers of applying cross-validation without considering the dependence of spindle properties on parameters. Parameters selected to optimize one performance metric or matching method are not optimized for others. Furthermore, elucidation of the stability of predicted indicators with respect to algorithm parameter selection is critical to practical application of these algorithms.

An 18-subject EEG data collection using a visual-oddball task, designed for benchmarking algorithms and headset performance comparisons

This data note describes an 18-subject EEG (electroencephalogram) data collection from an experiment in which subjects performed a standard visual oddball task. Several research projects have used this data to test artifact detection, classification, transfer learning, EEG preprocessing, blink detection, and automated annotation algorithms. We are releasing the data in three formats to enable benchmarking of EEG algorithms in many areas. The data was acquired using a Biosemi Active 2 EEG headset and includes 64 channels of EEG, 4 channels of EOG (electrooculogram), and 2 mastoid reference channels.

EEG-Annotate: Automated identification and labeling of events in continuous signals with applications to EEG

BACKGROUND

In controlled laboratory EEG experiments, researchers carefully mark events and analyze subject responses time-locked to these events. Unfortunately, such markers may not be available or may come with poor timing resolution for experiments conducted in less-controlled naturalistic environments.

NEW METHOD

We present an integrated event-identification method for identifying particular responses that occur in unlabeled continuously recorded EEG signals based on information from recordings of other subjects potentially performing related tasks. We introduce the idea of timing slack and timing-tolerant performance measures to deal with jitter inherent in such non-time-locked systems. We have developed an implementation available as an open-source MATLAB toolbox (http://github.com/VisLab/EEG-Annotate) and have made test data available in a separate data note.

RESULTS

We applied the method to identify visual presentation events (both target and non-target) in data from an unlabeled subject using labeled data from other subjects with good sensitivity and specificity. The method also identified actual visual presentation events in the data that were not previously marked in the experiment.

COMPARISON WITH EXISTING METHODS

Although the method uses traditional classifiers for initial stages, the problem of identifying events based on the presence of stereotypical EEG responses is the converse of the traditional stimulus-response paradigm and has not been addressed in its current form.

CONCLUSIONS

In addition to identifying potential events in unlabeled or incompletely labeled EEG, these methods also allow researchers to investigate whether particular stereotypical neural responses are present in other circumstances. Timing-tolerance has the added benefit of accommodating inter- and intra- subject timing variations.

Classification of imperfectly time-locked image RSVP events with EEG device

Classification based on EEG data in an RSVP experiment is considered. Although the latency in neural response relative to the stimulus onset time may be more realistically considered to vary across trials due to factors such as subject fatigue and environmental distractions, it is nevertheless assumed to be time-locked to the stimulus in most of the existing work as a means to alleviate the computational complexity. We consider here a more practical scenario that allows variation in response latency and develop a rigorous statistical formulation for modeling the uncertainty within the varying latency coupled with a likelihood ratio test (LRT) for classification. The new model not only improves the EEG classification performance, but also may predict the true stimulus onset time when this information is not precisely available. We test the proposed LRT algorithm on an EEG data set from an image RSVP experiment and show that, by admitting the latency variation, the proposed approach consistently outperforms a method that relies on perfect time-locking (AUC: 0.88 vs 0.86), especially when the stimulus onset time is not precisely available (AUC: 0.84 vs 0.71). Furthermore, the predicted stimulus onset times are highly enriched around the true onset time with p-value = 5.2 x 10(44).

Consumer attitudes towards beef and acceptability of enhanced beef

The objective of this study was to evaluate consumer quality characteristics of enhanced steaks and roasts derived from cattle supplemented with vitamin E during finishing, and to assess the attitudes of these consumers towards beef. Twelve steers were fed either a control (E-) diet or a diet supplemented with dl-alpha tocopheryl acetate (E+). Paired strip loins and rounds were either used as controls (C) or were pumped (P) to 110% of raw weight to contain 0.4% sodium chloride and 0.4% sodium tripolyphosphate in the final product. Consumers (n=103) evaluated roasts and steaks for juiciness, tenderness, saltiness, and overall acceptability on a 9-point hedonic scale. Enhanced steaks and roasts were more acceptable than non-enhanced controls; E+ steaks were less acceptable than E- steaks. A beef quality questionnaire revealed that color, price, visible fat and cut were the most important factors underlying beef steak purchase, while tenderness, flavor and juiciness were weighted most heavily with regard to eating satisfaction.

DETECT: a MATLAB toolbox for event detection and identification in time series, with applications to artifact detection in EEG signals

Recent advances in sensor and recording technology have allowed scientists to acquire very large time-series datasets. Researchers often analyze these datasets in the context of events, which are intervals of time where the properties of the signal change relative to a baseline signal. We have developed DETECT, a MATLAB toolbox for detecting event time intervals in long, multi-channel time series. Our primary goal is to produce a toolbox that is simple for researchers to use, allowing them to quickly train a model on multiple classes of events, assess the accuracy of the model, and determine how closely the results agree with their own manual identification of events without requiring extensive programming knowledge or machine learning experience. As an illustration, we discuss application of the DETECT toolbox for detecting signal artifacts found in continuous multi-channel EEG recordings and show the functionality of the tools found in the toolbox. We also discuss the application of DETECT for identifying irregular heartbeat waveforms found in electrocardiogram (ECG) data as an additional illustration.

Effect of dietary vitamin E supplementation on textural and aroma attributes of enhanced beef clod roasts in a cook/hot-hold situation

The objective of this study was to evaluate the effects of supplementing vitamin E into the diets of finishing cattle on quality characteristics of beef pumped with a phosphate/salt solution (enhanced) the cooked and held in a simulated foodservice situation. Twelve steers were fed either a control (E-) diet or a diet supplemented with dl-α-tocopheryl-acetate (E+). Paired clod roasts were either used as controls (C) or were pumped (P) to 110% of raw weight to contain 0.4% sodium chloride and 0.4% phosphate in the finished product. Following injection, clods were allowed to equilibrate then frozen. A flavor profile panel evaluated texture attributes and aroma characteristics of roasts immediately after cooking and after 1 and 2 h of hot-holding. Pumping improved taste and textural attributes of the hot-held clod roasts. Dietary vitamin E supplementation reduced thiobarbituric acid reactive substances (TBARS) from ∼0.61 to ∼0.42, but over the 2-h time period, did not significantly improve aroma quality of beef roasts.

Association between hsp60 messenger-RNA levels and Cisplatin resistance in human head and neck-cancer cell-lines

Development of resistance to cisplatin (cDDP) is a major obstacle in the cure of many cancers. Recently, a cDNA from cDDP-resistant human ovarian carcinoma cells was identified as the mitochondrial hsp60 chaperonin. The aim of this study was to determine the changes in expression of hsp60 during selection for cDDP resistance in two head and neck cancer cell lines, UMSCC5 and UMSCC10b and whether the emergence of resistance could be correlated with the level of hsp60 expression. We have selected cDDP-resistant variants of two squamous cell carcinoma cell lines, the UMSCC5 and UMSCC10b with levels of resistance varying from 1.5 to 6-fold. Concomitant with the emergence of resistance, the basal level of hsp60 increased 2 to 3-fold. In addition, less cDDP resistance as well as lower hsp60 levels were detected in cDDP resistant variants of the UMSCC10b cell line when selected in the presence of tamoxifen, suggesting a correlation between the intrinsic level of hsp60 expression and cDDP resistance. Using linear regression analysis both UMSCC5 and UMSCC10b cell lines demonstrated a high degree of correlation with coefficients of 0.91 and 0.90, respectively. In conclusion, the expression of hsp60 was closely related to the development of cDDP resistance and could be used as a marker for the emergence of cDDP resistance.

Characterization and robust classification of EEG signal from image RSVP events with independent time-frequency features

This paper considers the problem of automatic characterization and detection of target images in a rapid serial visual presentation (RSVP) task based on EEG data. A novel method that aims to identify single-trial event-related potentials (ERPs) in time-frequency is proposed, and a robust classifier with feature clustering is developed to better utilize the correlated ERP features. The method is applied to EEG recordings of a RSVP experiment with multiple sessions and subjects.

The results show that the target image events are mainly characterized by 3 distinct patterns in the time-frequency domain, i.e., a theta band (4.3 Hz) power boosting 300–700 ms after the target image onset, an alpha band (12 Hz) power boosting 500–1000 ms after the stimulus onset, and a delta band (2 Hz) power boosting after 500 ms. The most discriminant time-frequency features are power boosting and are relatively consistent among multiple sessions and subjects.

Since the original discriminant time-frequency features are highly correlated, we constructed the uncorrelated features using hierarchical clustering for better classification of target and non-target images. With feature clustering, performance (area under ROC) improved from 0.85 to 0.89 on within-session tests, and from 0.76 to 0.84 on cross-subject tests. The constructed uncorrelated features were more robust than the original discriminant features and corresponded to a number of local regions on the time-frequency plane.

Availability: The data and code are available at: http://compgenomics.cbi.utsa.edu/rsvp/index.html

Tissue expression of angiopoietin-like protein 4 in cattle

Angiopoietin-like protein 4 (ANGPTL4; also known as fasting-induced adipose factor) is a plasma protein that stimulates oxidation of fatty acids and inhibits fat accumulation. The gastrointestinal tract appears to play an important role in regulating plasma ANGPTL4 concentration in some situations and may be influenced by microbes within the gastrointestinal tract. Our aim was to determine which tissues express ANGPTL4 in the bovine. Rumen, omasum, abomasum, duodenum, jejunum, ileum, colon, pancreas, liver, and subcutaneous adipose tissue samples were collected postmortem from 2 steers. Abundance of ANGPTL4 messenger RNA was quantified by quantitative real-time PCR, and was most abundant in liver and adipose tissue (P < 0.05). We also detected ANGPTL4 messenger RNA throughout the gastrointestinal tract, although its abundance was approximately 10% of that found in liver and adipose tissue. Western blot analysis revealed that ANGPTL4 protein was most abundant in liver and adipose tissue (P < 0.05), but omasal, abomasal, and ileal samples contained at least 60% as much ANGPTL4 protein as the liver and adipose tissue samples, and the protein was detected in all tissues. Finally, cross-sections of the liver, pancreas, and rumen wall were used for indirect immunofluorescent detection of ANGPTL4. Despite the low abundance of ANGPTL4 measured by quantitative real-time PCR and Western blot in ruminal tissue, immunofluorescence demonstrated that expression of ANGPTL4 in ruminal epithelial cells was equivalent to or greater than that in liver hepatocytes. These findings indicate that, as in other species studied, liver and adipose tissue are key sources of ANGPTL4 in cattle. However, the protein was also highly abundant in ruminal epithelium, making it possible that commensal microbes may influence ANGPTL4 synthesis and secretion in the ruminant gastrointestinal tract.

Tracking thymocyte migration in situ

The dynamic process of thymocyte migration can now be visualized in real-time and in the context of the native thymic environment. With improved computational resources, key information can be extracted from real-time imaging data and the migratory behaviors of developing thymocytes can be quantitated. The extraction and exploitation of three dimensional data through time is providing new insight into the nature and regulation of intrathymic migration. In this review we discuss this interdisciplinary approach and the promise it holds for the study of thymocyte migration in situ.

Spiral dynamics of pulsating methane-oxygen flames on a circular burner

A premixed flame stabilized on a circular porous plug burner produces a uniform, steady luminous flame front. Throughout much of the parameter range hydrocarbon-oxygen mixtures form spiral-shaped fronts. In methane-oxygen flames at low pressure, the flame exhibits a sequence of states as a control parameter is decreased. These states include periodic rotation of a spiral front; precession of the spiral front in a direction opposite to its rotation, corresponding to doubly periodic petals-out meandering; and nonperiodic states with intermittent jumps associated with linear excursions of the tip, which occur after the spiral front has reached the boundary of the circular burner. We use Karhunen-Loeve (KL) analysis to find the coefficients of the dominant KL spatial eigenfunctions. Their phase space portraits and power spectra provide a description of the dynamics as flow rates are reduced and the system destabilizes. We discuss how these experimental results relate to previous theoretical studies that assume Euclidean symmetry for the experimental configuration.

Primary care physicians' experience with mental health consultation

A total of 684 primary care physicians in Wisconsin participated in a survey designed to explore their experiences of consulting with and referring patients to mental health care professionals. The respondents indicated that they had only moderate access to mental health care professionals, and even less access when a patient was covered by Medicare or Medicaid or had no insurance. Physicians in group practices that included at least one mental health professional reported having better access to care than those in practices that did not include mental health services. Perceived access to mental health care services was not related to community size or to a managed care setting.

Early thyrotoxic thyroiditis after radiotherapy for tonsillar carcinoma

Thyroiditis with hyperthyroidism is a recognized early complication of intrathyroidal irridiation by orally ingested radiolabeled iodine I 131, but has seldom been described following external delivery of radiotherapy to the thyroid bed. We treated a man who was initially seen with a clinical picture suggestive of hyperthyroidism after receiving a course of radiotherapy for tonsillar carcinoma. Laboratory studies and thyroidal radioiodine uptake confirmed the diagnosis of thyrotoxic thyroiditis, having onset within 2 weeks of completion of the course of radiotherapy. The literature concerning thyroiditis and thyroid function following external beam radiotherapy is reviewed. Because several of the clinical features of thyrotoxic thyroiditis may resemble those resulting from the cancer under treatment or complications of its therapy, we recommend evaluation of thyroid function at the conclusion of the course of radiotherapy and 2 weeks thereafter to exclude this self-limited and treatable cause of weight loss.

The Cochrane Library: a resource for current reviews of clinical evidence

The Cochrane Library is a tool for physicians and other health care practitioners seeking evidence to inform their decisions. The systematic reviews provide a high-quality synthesis of the current literature, saving time for busy people. To make the library more user-friendly, the collaboration plans to produce a consumer summary for each topic in the Database of Systematic Reviews and a cancer library aimed at the general public. In contrast to some of the questionable health-related resources on the Web, the Cochrane Library is an authoritative reference that can help physicians with everyday treatment decisions. The collaboration's commitment to keeping its resources up to date through vigorous support of reviewers should ensure that it remains a valuable Internet tool for physicians.

Human immunodeficiency virus (HIV) subtype surveillance of African-born persons at risk for group O and group N HIV infections in the United States

A population-based surveillance registry was used to identify human immunodeficiency virus (HIV)-infected persons in the United States at increased risk for group O and group N infections (those born in or near African countries where group O infection has been reported). Of 155 eligible subjects, 37 gave samples. By phylogenetic and serologic analysis, 32 were infected with group M (16 with subtype A, 5 with B, 7 with C, and 1 each with subtypes D, F2, G, and recombinant A/J) and 2 with group O but none with group N virus. For 3, samples could not be typed by serology or amplified by polymerase chain reaction using group M-, O-, or N-specific primers. In the United States, group O HIV infection is uncommon; no case of group N infection was found. African-born persons may have HIV strains typical of their birth country. Ongoing subtype surveillance may allow early identification of novel or emerging HIV strains.

Two outbreaks of multidrug-resistant Salmonella serotype typhimurium DT104 infections linked to raw-milk cheese in Northern California

CONTEXT

Salmonella serotype Typhimurium definitive type 104 (DT104), with resistance to 5 drugs (ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline), has emerged as the most common multidrug-resistant Salmonella strain in the United States. However, illnesses resulting from this strain have not been associated definitively with a source in this country.

OBJECTIVE

To determine the source of 2 outbreaks of Salmonella Typhimurium DT104.

DESIGN

Matched case-control study conducted between March 24 and April 5, 1997 (outbreak 1), enhanced surveillance for new cases dating from February 1, 1997 (outbreak 2), and environmental and laboratory investigations.

SETTING AND PARTICIPANTS

The case-control study included residents of 2 adjacent counties in northern California infected with the outbreak strain of Salmonella Typhimurium var Copenhagen and age-matched controls. For enhanced surveillance, a case was defined as Salmonella Typhimurium infection in a person exposed to fresh Mexican-style cheese.

MAIN OUTCOME MEASURES

Risk factors for infection and source of implicated food.

RESULTS

Outbreak 1 peaked in February 1997; 31 patients were confirmed by culture as having Salmonella Typhimurium var Copenhagen infection, isolates of which showed indistinguishable pulsed-field gel electrophoresis (PFGE) patterns. The outbreak strain was phage type DT104 with the 5-drug resistance pattern. Sixteen cases and 25 controls were enrolled in the case-control study; 15 of 16 Salmonella Typhimurium var Copenhagen cases compared with 14 of 24 matched controls reported eating unpasteurized Mexican-style cheese, (matched odds ratio, 7.9; 95% confidence interval, 1.1-354.9). Enhanced surveillance uncovered outbreak 2, which peaked in April 1997 and was caused by a non-Copenhagen variant of Salmonella Typhimurium. During outbreak 2, Salmonella Typhimurium was isolated from 79 persons who ate fresh Mexican-style cheese from street vendors and from cheese samples and raw milk. The PFGE pattern of the milk isolate matched 1 of the 3 patterns recovered from patients; all strains were phage type DT104b with the 5-drug resistance pattern.

CONCLUSION

Raw-milk products pose a risk for multidrug-resistant Salmonella Typhimurium DT104 infections.

Time course of ADCw changes in ischemic stroke: beyond the human eye!

BACKGROUND AND PURPOSE

Using newly developed computerized image analysis, we studied the heterogeneity of apparent diffusion coefficient of water (ADCw) values in human ischemic stroke within 10 hours of onset.

METHODS

Echo-planar trace diffusion-weighted images from 9 patients with focal cortical ischemic stroke were obtained within 10 hours of symptom onset. An Iterative Self-Organizing Data Analysis (ISODATA) clustering algorithm was implemented to segment different tissue types with a series of DW images. ADCw maps were calculated from 4 DW images on a pixel-by-pixel basis. The segmented zones within the lesion were characterized as low, pseudonormal, or high, expressed as a ratio of the mean+/-SD of ADCw of contralateral noninvolved tissue.

RESULTS

The average ADCW in the ischemic stroke region within 10 hours of onset was significantly depressed compared with homologous contralateral tissue (626.6+/-76.8 versus 842.9+/-60.4x10(-6) mm2/s; P<0.0001). Nevertheless, ISODATA segmentation yielded multiple zones within the stroke region that were characterized as low, pseudonormal, and high. The mean proportion of low:pseudonormal:high was 72%:20%:8%.

CONCLUSIONS

Despite low average ADCW, computer-assisted segmentation of DW MRI detected heterogeneous zones within ischemic lesions corresponding to low, pseudonormal, and high ADCw not visible to the human eye. This supports acute elevation of ADCw in human ischemic stroke and, accordingly, different temporal rates of tissue evolution toward infarction.

Phase III trial of modulation of cisplatin/fluorouracil chemotherapy by interferon alfa-2b in patients with recurrent or metastatic head and neck cancer. Head and Neck Interferon Cooperative Study Group

PURPOSE

In preclinical experiments, interferon alfa modulates the anticancer activity of fluorouracil (5-FU) and cisplatin (CDDP). To test this effect clinically in patients with recurrent or metastatic head and neck cancer (RMHNC), a multicenter randomized controlled trial with CDDP and 5-FU with or without interferon alfa-2b (IFNalpha) was performed.

PATIENTS AND METHODS

Eligible patients had histologically confirmed RMHNC; a good performance status; measurable disease; adequate bone marrow, hepatic, and renal function; no prior chemotherapy for recurrent or metastatic disease; only one chemotherapy regimen administered with previous local therapy; and a treatment-free interval of at least 3 months following previous local therapy. Patients were randomized and stratified according to treatment center, and prior radiotherapy and chemotherapy. The treatment regimen consisted of CDDP 100 mg/m2 on day 1 and 5-FU 1,000 mg/m2/d by continuous infusion for 96 hours (days 1 to 4), without (arm A) or with (arm B) IFNg alpha 3 x 10(6) U/d subcutaneously on days 1 to 5. Cycles were repeated every 21 days.

RESULTS

One hundred twenty-two patients were entered on each arm. The response rate (RR) was similar in both arms (arm A: complete response [CR] 10.7%, partial response [PR] 36.4%; arm B: CR 6.8%, PR 31.6%) (.70 < P < .50). There was no difference in median survival between the two arms (arm A 6.3 months v arm B 6.0 months; P = .49). Anorexia, fever, leukopenia, and thrombocytopenia grade III to IV were significantly more frequent in the IFNalpha arm.

CONCLUSION

Modulation of CDDP and 5-FU with IFNalpha as used in this study does not improve the RR or the median survival in patients with RMHNC. Patients on both study arms had a poor prognosis, which indicates the need for novel therapies.

Anti-immunoglobulin E treatment decreases worm burden and egg production in Schistosoma mansoni-infected normal and interferon gamma knockout mice

The immunoglobulin E (IgE) response is generally considered an essential component of the host defense against parasitic helminths such as Schistosoma mansoni. In contrast, work on antischistosome vaccines suggests that interferon gamma (IFN-gamma) is the critical immune mediator for vaccine-induced immunity to the parasite. In this study, the total IgE response to a primary S. mansoni infection was suppressed by anti-IgE treatment in both normal mice and in mice with defective IFN genes (gene knockout [GKO]). Reduction of the IgE response resulted in decreased worm burden and a decrease in the number of eggs produced per worm in both normal and GKO mice. Whereas anti-IgE treatment also resulted in reduced hepatosplenomegaly, granulomas around existing schistosome eggs showed normal cellularity. Serum interleukin 4 levels fell in response to the reduction in serum IgE as well. The data suggest that IgE plays a detrimental, rather than beneficial, role for the host in schistosomiasis. Furthermore, the absence of IFN-gamma was found to be of little consequence to the host-response to adults or eggs in a primary schistosome infection.

Reference accuracy in the dermatologic literature

BACKGROUND

The reference list is an important part of a scientific article. To be useful it must be accurate.

OBJECTIVE

The purpose of this study was to evaluate the accuracy of references in the dermatologic literature.

METHODS

We randomly selected 240 references (60 per journal) from the Archives of Dermatology, the British Journal of Dermatology, this Journal, and the Journal of Investigative Dermatology and checked them against the original articles.

RESULTS

The overall rate of citation error (the information identifying the source) was 41%, and the quotation error (inconsistency between the statement referenced and the original source) was 35%. Only 36% of references were free of error.

CONCLUSION

This study shows that the rate of citation and quotation errors is unacceptably high in the dermatologic literature, which significantly diminishes the value of the reference list.

Administration of an anti-IgE antibody inhibits CD23 expression and IgE production in vivo

High IgE responder BDF1 mice were immunized intraperitoneally (i.p.) with dinitrophenol4 (DNP4)-ovalbumin (OVA) in alum concomitant with intravenous (i.v.) administration of an anti-IgE monoclonal antibody (mAb). IgE levels were undetectable in mice treated with the anti-IgE antibody, whereas mice treated with isotype-matched irrelevant mAb had IgE levels comparable to that of untreated, immunized mice. Subsequent antigen challenges with DNP4-OVA, either at weekly or monthly intervals, failed to evoke an IgE response for greater than 2 months in mice treated with anti-IgE during the primary sensitization, even though the terminal half-life of the anti-IgE antibody was 7 days. This inhibition was specific for DNP4-OVA since the DNP4-OVA-suppressed mice were able to respond to keyhole limpet haemocyanin (KLH). To investigate the effects of antibody treatment at the cellular level, passive transfer experiments were performed. The primary DNP-specific IgE response of adoptive transfer recipient mice was the same whether the donor cells were from mice treated with IgG or anti-IgE. Transfer of enriched T- or B-cell populations indicated that T-cell help was not compromised by administration of the anti-IgE mAb. However, splenocytes from the anti-IgE-treated mice failed to synthesize IgE in vitro, and flow cytometric analysis of B cells from anti-IgE-treated mice showed a dose-dependent decrease in CD23+ cells following antibody treatment, which correlated with decreased serum IgE levels. Taken together, the results of these studies suggest that anti-IgE treatment suppresses IgE responses via effects on B cells rather than T cells, possibly through effects on CD23-dependent pathways.

Immunological effects of insulin-like growth factor-I--enhancement of immunoglobulin synthesis

In addition to its activity as a metabolic hormone and a regulator of somatic growth, insulin-like growth factor-I (IGF-I) has cytokine-like activities on lymphoid cells. A 14-day infusion of recombinant human (rh)IGF-I increased lymphocyte numbers in all the peripheral lymphoid organs examined. This increase was apparent for up to 3 weeks following cessation of hormone treatment. A second administration of rhIGF-I, given when the lymphocyte numbers in the rhIGF-I-treated mice had returned to control values, resulted in similar increases in the peripheral T and B cell populations. This increase in lymphocyte numbers had functional significance, since rhIGF-I-treated mice produced elevated antibody titres following primary or secondary antigen challenge compared with controls. In addition, when rhIGF-I-treated mice were immunized with a suboptimal dose of antigen they produced antibody titres which were equivalent to those generated by immunization with optimal doses of antigen. When examined in vitro, addition of rhIGF-I alone to cultures of splenocytes from antigen-primed mice stimulated immunoglobulin synthesis. These studies suggest that IGF-I produced locally by thymic and bone marrow stromal cells may be a natural component of B and T cell lymphopoiesis.

Insulin-like growth factor-1 stimulation of lymphopoiesis

We show that treatment of adult mice with recombinant human insulin-like growth factor 1 (rhIGF-1) induces striking modifications in lymphocyte number and function. 9-mo-old male mice received rhIGF-1 (4 mg/kg per d) or its excipient by subcutaneous infusion from osmotic minipumps for 7 or 14 d. Mice were weighed daily and bled at sacrifice; the spleen and thymus were harvested and single cell suspensions were made for analysis of cell phenotype and cell number. The responses of splenocytes to mitogens (concanavalin A, lipopolysaccharide, and pokeweed mitogen), alloantigens and dinitrophenyl ovalbumin were measured. After either 7 or 14 d of treatment, rhIGF-1 had an overall whole-body anabolic effect, resulting in increased body and organ weights with prominent increases in the weight of the spleen and thymus. Furthermore, the rhIGF-1 treated mice were normoglycemic but had reduced blood urea nitrogens, again reflecting the anabolic activity of rhIGF-1. The increased spleen and thymus weights were associated with a large increase in the number of lymphocytes in both organs. In addition to an increase in T cells, specifically CD4+ T cells, a dramatic increase in splenic B cells was also observed. This increase was accompanied by an enhanced responsiveness to dinitrophenyl ovalbumin resulting in increased immunoglobulin production. However, despite the increases in cellularity, there was a decrease in the in vitro responses of spleen cells to mitogens after 7 d of rhIGF-1 treatment. In contrast, treatment with rhIGF-1 for 14 d increased both the cell number and mitogenic responses of splenocytes suggesting that some time is required for the cells populating the peripheral organs to gain mitogenic responsiveness. It is clear from these data that rhIGF-1, at doses that have whole-body anabolic activity, can expand cell number in lymphoid tissue in a normal adult mouse. These dual effects of rhIGF-1, of increasing lymphocyte number and activity, indicate that, in a normal adult animal, rhIGF-1 can cause major changes in lymphoid tissues that are of potential benefit to the functioning of the immune system.

Activin induces cell death in hepatocytes in vivo and in vitro

While studying endocrine responses to activin in female rats, we discovered that activin caused a marked reduction in liver mass. The regressed livers exhibited no gross signs of necrosis or infarction, but histopathological evaluation revealed extensive cell death in the centrilobular regions. The dying cells appeared to fragment into structures resembling apoptotic bodies. Liver mass and histological appearance were restored after cessation of activin infusion, indicating that on an organ level, this effect was reversible. To determine whether the effects observed in vivo were caused by direct actions on the liver, we then tested activin on isolated hepatocytes in serum-free medium. Under these conditions, activin caused many hepatocytes to undergo fragmentation, which was accompanied by a loss of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-reducing activity, an index of viability. We compared the effects of activin with those of transforming growth factor-beta because activin is structurally related to transforming growth factor-beta and because transforming growth factor-beta has been shown previously to induce cell death in hepatocytes. Both proteins caused cell death of comparable magnitude, as defined by the extent of loss of MTT-reducing activity, but transforming growth factor-beta was active at one tenth of the effective activin concentrations. A neutralizing monoclonal antibody to transforming growth factor-beta blocked the response to transforming growth factor-beta but had no effect on the response to activin. Conversely, follistatin, an activin-binding protein, blocked the response to activin but not to transforming growth factor-beta. Inhibin, which antagonizes the effects of activin in many systems, had little effect on the response to activin. Activin and transforming growth factor-beta differed in their onset of action; exposure to transforming growth factor-beta for only 1 hr induced a maximal response, whereas maximal response to activin required its continuous presence for 24 hr. These results show a novel effect of activin on cell death in hepatocytes in vivo and in vitro, suggesting that activin may have a previously unrecognized role in regulating hepatic function.

Human IgE receptor alpha-chain IgG chimera blocks passive cutaneous anaphylaxis reaction in vivo

Cross-linking of the high affinity IgE receptor (Fc epsilon RI) expressed on mast cells and basophils is essential for triggering anaphylaxis in vivo. Previously, other investigators have tried to produce competitive inhibitors using IgE peptide analogues and anti-IgE antibodies with limited success. To create a novel specific inhibitor of IgE that can block binding of IgE to Fc epsilon RI without the capacity to stimulate degranulation, we made an Fc epsilon RI-IgG immunoadhesin. The Fc epsilon RI-IgG was constructed by gene fusion of the extracellular portion of the human alpha-chain of Fc epsilon RI, which contains the high affinity binding site for IgE, with a truncated human IgG1 H chain C region. The Fc epsilon RI-IgG recognizes both human and murine IgE. Coincubation of Fc epsilon RI-IgG with murine IgE prevented sensitization of RBL-2H3 cells and the subsequent histamine release in response to anti-IgE. Similarly, when the Fc epsilon RI-IgG was preincubated with equimolar concentrations of either hyperimmune mouse sera or purified mouse IgE, it completely blocked the passive cutaneous anaphylaxis reaction in rats. Furthermore, i.v. administration of Fc epsilon RI-IgG following intracutaneous injection of serum from DNP-immunized mice was able to block the passive cutaneous anaphylaxis reaction in a time-dependent fashion. These results demonstrate that Fc epsilon RI-IgG is a potent inhibitor of IgE binding to intracutaneous mast cells in vivo and may prove clinically useful for the treatment of IgE-mediated disease.