Problematic Cannabis Use Is Associated with Reduced Rectal Microbial Species Richness and Diversity Among a Pilot Sample of Young Sexual and Gender Minorities

Compared to young heterosexual men, young sexual and gender minorities (YSGM) have elevated systemic inflammation and unique intestinal microbial profiles, influenced by HIV infection and substance use. However, links between cannabis use and microbial dysbiosis in this population have not been well described. In this pilot study, we aimed to characterize the complex interrelationships between cannabis use and microbial community structure in YSGM in relationship to HIV status. Cannabis use was assessed by self-administered Cannabis Use Disorder Identification Test (CUDIT) questionnaires and rectal microbial community alpha-diversity metrics were assessed via 16S ribosomal ribonucleic acid (rRNA) sequencing in a subset of YSGM (n = 42) in the RADAR cohort (aged 16-29) in Chicago. Multivariable regression models were used to assess the relationship between cannabis use and microbiome alpha-diversity metrics, adjusting for HIV status and other risk characteristics, including inflammation, which was evaluated by plasma levels of C-reactive protein (CRP). Problematic cannabis use, but not general use, was significantly inversely associated with microbial community richness (Adj. Beta = -8.13; 95% confidence interval [CI]: -15.68 to -0.59) and Shannon diversity (Adj. Beta = -0.04; 95% CI: -0.07 to 0.009). No significant association was observed between CUDIT score and community evenness, nor was any significant moderation observed by HIV status. We observed that problematic cannabis use was associated with reduced microbial community richness and Shannon diversity, adjusting for within population differences in inflammation and HIV status. Future research should aim to assess how cannabis use contributes to microbiome-related health factors among YSGM and if decreasing cannabis use can restore gut microbial community structure.

Inflammation Assessed by Latent Profiling is Associated with Stress and Suicidality but not Depression: Findings from the RADAR Cohort Study

Past research has suggested that sexual and gender minorities experience elevated levels of systemic inflammation which in turn has been linked to worse mental health outcomes. Therefore, the goals of this work are to develop a better understanding of the relationship between mental health variables and inflammation among this high-risk population. Data were collected among a sample of young men who have sex with men and transgender women (YMSM/TGW, N=685) aged 16-20 at the time of enrollment. Multiplex plasma cytokine and inflammatory biomarkers were quantified. Mental health variables were self-reported and included perceived stress, depression, and suicidal ideation. Latent profile analyses (i.e., latent class analyses intended for continuous variables) were utilized to identify four unique profiles of individuals with similar inflammatory markers followed by adjusted multinomial logistic regression to estimate the association between inflammatory profiles and mental health variables. Participants experienced moderate levels of perceived stress, normal levels of depression and ten percent reported suicidal ideation in the past six months. Multinomial regression models indicated that being in the highest inflammation profile, compared to the lowest inflammation profile, was significantly associated only with increased perceived stress and suicidal ideation. In sum, we observed significant relationships between inflammation and both perceived stress and suicidal ideation, but not between inflammation and depression. Future research should continue to assess these relationships using longitudinal data as they are intricate and likely bidirectional and may be key to reducing health disparities among this population.

mTOR regulation of metabolism limits LPS-induced monocyte inflammatory and procoagulant responses

Translocated lipopolysaccharide (LPS) activates monocytes via TLR4 and is hypothesized to increase cardiovascular disease risk in persons living with HIV. We tested whether mTOR activity supports LPS-stimulated monocyte production of pro-inflammatory cytokines and tissue factor (TF), as it propels the inflammatory response in several immune cell types besides monocytes. However, multi-omics analyses here demonstrate that mTOR activates a metabolic pathway that limits abundance of these gene products in monocytes. Treatment of primary human monocytes with catalytic mTOR inhibitors (mTORi) increased LPS-induced polyfunctional responses, including production of IL-1β, IL-6, and the pro-coagulant, TF. NF-κB-driven transcriptional activity is enhanced with LPS stimulation after mTORi treatment to increase expression of F3 (TF). Moreover, intracellular NAD+ availability is restricted due to decreased salvage pathway synthesis. These results document mTOR-mediated restraint of the LPS-induced transcriptional response in monocytes and a metabolic mechanism informing strategies to reverse enhanced risk of coagulopathy in pro-inflammatory states.

TWO NEW SPECIES OF STILLABOTHRIUM (CESTODA: RHINEBOTHRIIDEA) FROM STINGRAYS FROM NORTHERN AUSTRALIA AND ONE NEW COMBINATION

A study of cestode specimens that were collected during survey work on elasmobranchs collected from Taiwan and Northern Territory, Australia, revealed the presence of 1 new combination into the genus Stillabothrium (Rhinebothriidea: Escherbothriidae) and 2 new species of the genus. Phyllobothrium biacetabulatum, collected from Rhinobatos schlegelii, is transferred to Stillabothrium and its description is emended, as is the diagnosis for the genus Stillabothrium and the family Escherbothriidae. Stillabothrium biacetabulatum n. comb. differs from existing species of the genus in that the face of its bothridia is laced with a network of longitudinal and horizontal muscle fibers that do not contribute to the formation of septa. Stillabothrium lunae n. sp. is described from Himantura leoparda and differs from existing species of the genus in that its bothridium possesses an anterior field of 7-8 loculi that are wider than long. Stillabothrium mariae n. sp. is described from Maculabatis astra. This species differs from all species of Stillabothrium except Stillabothrium campbelli in possessing 10-12 horizontally oriented bothridial loculi. Stillabothrium mariae n. sp. differs from S. campbelli in having longer bothridia and from all other species of Stillabothrium in that it lacks, rather than possesses, conspicuous septa and loculi that are longer than wide in the posterior region of its bothridia. Bayesian and parsimony-bootstrap analysis of 28S rDNA revealed S. biacetabulatum n. comb., S. lunae n. sp., and S. mariae n. sp. to be part of Clade 1 of Stillabothrium, with S. biacetabulatum n. comb. being the sister species to S. mariae n. sp. Stillabothrium lunae n. sp. was found to be the sister species to Stillabothrium borneoense.

Fibrin gel enhances the antitumor effects of chimeric antigen receptor T cells in glioblastoma

Regional delivery of chimeric antigen receptor (CAR) T cells in glioblastoma represents a rational therapeutic approach as an alternative to intravenous administration to avoid the blood-brain barrier impediment. Here, we developed a fibrin gel that accommodates CAR-T cell loading and promotes their gradual release. Using a model of subtotal glioblastoma resection, we demonstrated that the fibrin-based gel delivery of CAR-T cells within the surgical cavity enables superior antitumor activity compared to CAR-T cells directly inoculated into the tumor resection cavity.

Genetic and Metabolic Determinants of Plasma Levels of ANGPTL8

CONTEXT

ANGPTL8 (A8) plays a key role in determining the tissue fate of circulating triglycerides (TGs). Plasma A8 levels are associated with several parameters of glucose and TG metabolism, but the causality of these relationships and the contribution of genetic variants to differences in A8 levels have not been explored.

OBJECTIVE

To characterize the frequency distribution of plasma A8 levels in a diverse population using a newly-developed enzyme-linked immunosorbent assay (ELISA) and to identify genetic factors contributing to differences in plasma A8 levels.

METHODS

We studied a population-based sample of Dallas County, comprising individuals in the Dallas Heart Study (DHS-1, n = 3538; DHS-2, n = 3283), including 2131 individuals with repeated measurements 7 to 9 years apart (age 18-85 years; >55% female; 52% Black; 29% White; 17% Hispanic; and 2% other). The main outcome measures were associations of A8 levels with body mass index (BMI), plasma levels of glucose, insulin, lipids, and hepatic TGs, as well as DNA variants identified by exome-wide sequencing.

RESULTS

A8 levels varied over a 150-fold range (2.1-318 ng/mL; median, 13.3 ng/mL) and differed between racial/ethnic groups (Blacks > Hispanics > Whites). A8 levels correlated with BMI, fasting glucose, insulin, and TG levels. A variant in A8, R59W, accounted for 17% of the interindividual variation in A8 levels but was not associated with the metabolic parameters correlated with plasma A8 concentrations.

CONCLUSIONS

A8 levels were strongly associated with indices of glucose and TG metabolism, but the lack of association of genetic variants at the A8 locus that impact A8 levels with these parameters indicates that differences in A8 levels are not causally related to the associated metabolic phenotypes.

mTOR Overcomes Multiple Metabolic Restrictions to Enable HIV-1 Reverse Transcription and Intracellular Transport

Cellular metabolism governs the susceptibility of CD4 T cells to HIV-1 infection. Multiple early post-fusion steps of HIV-1 replication are restricted in resting peripheral blood CD4 T cells; however, molecular mechanisms that underlie metabolic control of these steps remain undefined. Here, we show that mTOR activity following T cell stimulatory signals overcomes metabolic restrictions in these cells by enabling the expansion of dNTPs to fuel HIV-1 reverse transcription (RT), as well as increasing acetyl-CoA to stabilize microtubules that transport RT products. We find that catalytic mTOR inhibition diminishes the expansion of pools of both of these metabolites by limiting glucose and glutamine utilization in several pathways, thereby suppressing HIV-1 infection. We demonstrate how mTOR-coordinated biosyntheses enable the early steps of HIV-1 replication, add metabolic mechanisms by which mTOR inhibitors block HIV-1, and identify some metabolic modules downstream of mTOR as druggable targets for HIV-1 inhibition.

Clinical and cost-effectiveness of bracing in symptomatic knee osteoarthritis management: protocol for a multicentre, primary care, randomised, parallel-group, superiority trial

BACKGROUND

Brace effectiveness for knee osteoarthritis (OA) remains unclear and international guidelines offer conflicting recommendations. Our trial will determine the clinical and cost-effectiveness of adding knee bracing (matched to patients' clinical and radiographic presentation and with adherence support) to a package of advice, written information and exercise instruction delivered by physiotherapists.

METHODS AND ANALYSIS

A multicentre, pragmatic, two-parallel group, single-blind, superiority, randomised controlled trial with internal pilot and nested qualitative study. 434 eligible participants with symptomatic knee OA identified from general practice, physiotherapy referrals and self-referral will be randomised 1:1 to advice, written information and exercise instruction and knee brace versus advice, written information and exercise instruction alone. The primary analysis will be intention-to-treat comparing treatment arms on the primary outcome (Knee Osteoarthritis Outcomes Score (KOOS)-5) (composite knee score) at the primary endpoint (6 months) adjusted for prespecified covariates. Secondary analysis of KOOS subscales (pain, other symptoms, activities of daily living, function in sport and recreation, knee-related quality of life), self-reported pain, instability (buckling), treatment response, physical activity, social participation, self-efficacy and treatment acceptability will occur at 3, 6, and 12 months postrandomisation. Analysis of covariance and logistic regression will model continuous and dichotomous outcomes, respectively. Treatment effect estimates will be presented as mean differences or ORs with 95% CIs. Economic evaluation will estimate cost-effectiveness. Semistructured interviews to explore acceptability and experiences of trial interventions will be conducted with participants and physiotherapists delivering interventions.

ETHICS AND DISSEMINATION

North West Preston Research Ethics Committee, the Health Research Authority and Health and Care Research in Wales approved the study (REC Reference: 19/NW/0183; IRAS Reference: 247370). This protocol has been coproduced with stakeholders including patients and public. Findings will be disseminated to patients and a range of stakeholders.

TRIAL REGISTRATION NUMBER

ISRCTN28555470.

Plasma C-reactive protein is lower among marijuana using HIV-negative individuals but not among persons living with HIV

The use of marijuana is highly prevalent among young men who have sex with men (YMSM). Past work has also shown that inflammation is elevated among YMSM, independent of HIV status. Here, we aim to examine the relationship between marijuana use and inflammation among this high-risk cohort, relative to use of other substances. Data were collected among YMSM aged 16-29 in Chicago. Multiplex cytokine and inflammatory biomarker assays were run on plasma from all persons living with HIV (PLWH) (n = 195) and a subset of HIV-negative participants (n = 489). Bivariate analyses and multivariable models assessed relationships between various substances and inflammatory biomarkers. Models were stratified by HIV status and adjusted for demographic characteristics. Most participants reported use of marijuana in the past 30 days (416, 60.8%). Mean blood C-reactive protein (CRP) levels were above the upper limit of normal (3.0 mg/L), indicative of increased risk for cardiovascular disease (mean CRP was 3.9 mg/L; SD = 8.5). In adjusted, stratified analyses, CRP was significantly lower among participants reporting frequent marijuana use (≥ 6 times per month), relative to those reporting never using marijuana, (β = - 0.38; 95% CI: - 0.73, - 0.03). However, this was entirely accounted for by an association among the HIV-negative participants and there was no significant association between marijuana use and blood CRP level among the PLWH. In summary, YMSM had markedly elevated marijuana use and blood CRP levels. Frequent marijuana use was associated with lower inflammation among only those not diagnosed with HIV. Further research is needed to explicate why there are differences between HIV-negative participants and PLWH and to leverage this information to characterize biological mechanisms by which marijuana decreases inflammation.

A Proportion of Self-Collected Rectal Swabs Yield Human Immunodeficiency Virus Sequences Phylogenetically Related to Those from Plasma Human Immunodeficiency Virus RNA

We determined HIV-1 pol gene sequences from self-collected rectal swabs of HIV-positive young men who have sex with men and transgender women. HIV-1 pol was amplified from 39/96 (41%) rectal swabs, including 29/77 (38%) prevalent and 10/19 (53%) incident HIV-1 infections (p < .001). Pol did not amplify from rectal swabs from participants with plasma viral load <1,000 copies/mL. Each rectal swab-derived amplicon consensus sequence was most closely related to the paired plasma virion RNA-derived sequence from the same participant. Results document a rectal mucosal source of HIV-1 in infected persons and suggest usefulness for noninvasive study of biological mechanisms underlying the epidemiologic risk to an insertive partner of HIV-1 acquisition during condomless anal sex.

B7-H3-redirected chimeric antigen receptor T cells target glioblastoma and neurospheres

BACKGROUND

The dismal survival of glioblastoma (GBM) patients urgently calls for the development of new treatments. Chimeric antigen receptor T (CAR-T) cells are an attractive strategy, but preclinical and clinical studies in GBM have shown that heterogeneous expression of the antigens targeted so far causes tumor escape, highlighting the need for the identification of new targets. We explored if B7-H3 is a valuable target for CAR-T cells in GBM.

METHODS

We compared mRNA expression of antigens in GBM using TCGA data, and validated B7-H3 expression by immunohistochemistry. We then tested the antitumor activity of B7-H3-redirected CAR-T cells against GBM cell lines and patient-derived GBM neurospheres in vitro and in xenograft murine models.

FINDINGS

B7-H3 mRNA and protein are overexpressed in GBM relative to normal brain in all GBM subtypes. Of the 46 specimens analyzed by immunohistochemistry, 76% showed high B7-H3 expression, 22% had detectable, but low B7-H3 expression and 2% were negative, as was normal brain. All 20 patient-derived neurospheres showed ubiquitous B7-H3 expression. B7-H3-redirected CAR-T cells effectively targeted GBM cell lines and neurospheres in vitro and in vivo. No significant differences were found between CD28 and 4-1BB co-stimulation, although CD28-co-stimulated CAR-T cells released more inflammatory cytokines.

INTERPRETATION

We demonstrated that B7-H3 is highly expressed in GBM specimens and neurospheres that contain putative cancer stem cells, and that B7-H3-redirected CAR-T cells can effectively control tumor growth. Therefore, B7-H3 represents a promising target in GBM. FUND: Alex's Lemonade Stand Foundation; Il Fondo di Gio Onlus; National Cancer Institute; Burroughs Wellcome Fund.

Abstract 700: Development of a second-generation TRAIL agonist and predictive biomarker profile for colorectal cancer

In colorectal cancer (CRC), RAS mutated cancers comprise 30-50%, for which there are limited treatment options. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has been found to selectively induce cell death in 50% of the CRC cell lines tested in vitro and this appears to be independent of RAS mutation status. Minimal clinical success was observed for first generation TRAIL receptor agonists primarily due to poor agonist activity and poor bioavailability. In addition, a biomarker to identify responsive patients was lacking. Here we present the therapeutic development of MM-201, a next generation TRAIL receptor agonist, and its companion biomarker strategy. MM-201 is composed of an IgG1 Fc fused to a single chain TRAIL trimer (Fc-scTRAIL) engineered for improved stability and activity. Using TRAIL surface display on yeast, we identified three mutations (R130G/N228S/I247V) from a random mutagenesis library that lead to enhanced surface expression and DR5 binding. Incorporation of these three mutations into each TRAIL protomer of MM-201 resulted in an improvement of greater than 10°C in TM and an extended serum half-life of 33 hours in mice compared to wild-type Fc-scTRAIL and comparable activity in a panel of colorectal cancer (CRC) cell lines. To uncover predictive biomarkers for MM-201, we used continuous logic gate analysis on a publicly available dataset of cell survival for 27 CRC cell lines treated with cross-linked TRAIL cytokine. Using this dataset and gene expression data from Cancer Cell Line Encyclopedia, we explored combinations of 33 differentially expressed genes in the apoptosis pathway and identified a two gene biomarker signature that positively correlated with TRAIL response in CRC cell lines. The combined signature of high DR4 and low cIAP-1 was identified with a correlation coefficient of 0.99 with MM-201 response across 15 CRC cell lines both in vitro and in vivo. Subsequently we evaluated MM-201 and our biomarker approach in vivo, in a group of five CRC patient-derived xenograft (PDX) models. Four of the five models were sensitive to MM-201, with an average tumor growth inhibition (TGI) of 91%. The relative expression of DR4 and cIAP-1 in each of the PDX models was measured by RT-qPCR and the biomarker scores were observed to be significantly higher for all responding models. Given the responses observed in preclinical models, we used TCGA data to assess biomarker prevalence in patient tumor tissues. This analysis predicted that 59% of samples would have a biomarker score greater than 0.5, which correlates to a 75% reduction in cell viability in vitro. In contrast, only 12% of normal tissues had a score in this range. Our biomarker signature identifies a potentially responsive patient population and when combined with our next generation TRAIL agonist, MM-201, has the potential for development in CRC, especially for RAS mutated cancers.

Citation Format: Sara Ghassemifar, Yasmin Hashambhoy-Ramsay, Haluk Yuzugullu, Tamara Utermark, Violette Paragas, Tim Maiwald, Lia Luus, Maja Razlog, Hannah Hudson, Diane Chai, Birgit Schoeberl, C. Patrick Reynolds, Peter Sorger, Andrew J. Sawyer, Daryl C. Drummond, Eric Tam. Development of a second-generation TRAIL agonist and predictive biomarker profile for colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 700.

Abstract 3842: Design and engineering of TRAIL fusion proteins for cancer therapy

Protein-based agonists of apoptotic death receptors have shown remarkable preclinical efficacy but limited clinical response. The short circulating half-life of recombinant human TRAIL and the necessity of Fc-mediated clustering for potentiating agonistic antibodies against DR4 and DR5 have been proposed to be major impediments to the clinical success of this class. To address these limitations we have created Fc-scTRAIL, a single fusion polypeptide consisting of an IgG1 Fc region followed by three successive TRAIL monomers connected by two fifteen-amino acid linkers. While Fc-scTRAIL showed potent activity in vitro, we observed a low TM (48 °C) and rapid inactivation in serum indicating protein instability. Subsequently, we applied a directed evolution approach using yeast surface display to identify mutations that would stabilize the TRAIL trimer. When individual mutations were transferred to the Fc-scTRAIL format, we observed a dramatic increase in the TM (66-70 °C) while the combination of three mutations improved serum stability by ten-fold. Stabilized Fc-scTRAIL shows greater pro-apoptotic activity across a panel of cancer cell lines when compared to mapatumumab (anti-DR4) and drozitumab (anti-DR5), or the combination of antibodies even in the presence of anti-Fc cross-linking. Moreover, anti-Fc did not improve Fc-scTRAIL activity suggesting that the hexavalent design of the molecule maximizes death receptor activation. Currently, in vivo evaluation of Fc-scTRAIL for pharmacokinetic properties and activity is underway. We believe this format, when combined with an appropriate patient selection strategy, will result in improved clinical outcomes.

Citation Format: Eric M. Tam, Hannah Hudson, Tamara Dake, Sara Ghassemifar, Andreas Raue, Yasmin Hashambhoy-Ramsay, Stephen L. Sazinsky, Anahita Daruwalla, Neeraj Kohli, Lihui Xu, Charlotte F. Mc Donagh, Birgit Schoeberl, Diana H. Chai. Design and engineering of TRAIL fusion proteins for cancer therapy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3842.

Abstract B1-29: The effect of higher-order receptor clusters on TRAIL induced apoptotic signaling

The trimeric TNF-related apoptosis-inducing ligand (TRAIL) is an endogenous ligand that binds to trimeric death receptors (DR4/5). TRAIL is known to induce apoptosis mainly in malignant cells while normal cells remain unaffected. This makes TRAIL a most interesting target for cancer therapy.

We investigate the effects of ligand valency on the degree of Caspase-8 activation and apoptosis induction. As a model system we use the semi-sensitive cell line DU145 and multivalent anti-DR5 fibronectin domains that can potentially form higher-order receptor clusters. In order to disentangle the effects of receptor clusters of different size, a dynamic model of ligand-receptor binding and Caspase-8 activation is coupled to a model of cell growth and cell death. The dynamic model is calibrated using quantitative experimental data of ligand on cell binding, Caspase-8 activity and cell viability.

Our results show that higher-order receptor clusters do amplify apoptotic signaling. The model predicts that receptor clusters of size three and six are more abundant than others, indicating the special role of preformed receptor trimers. However, Caspase-8 activation only increases after receptor clusters of size larger than three. On the cell population level, the model can quantitatively predict the induction of apoptosis in this cell line. This work is an important step towards an integrative model of TRAIL induced apoptosis that finally aims at the understanding of heterogeneity both on a single cell level across cell lines.

Citation Format: Andreas Raue, Diana Chai, Hannah Hudson, Eric Tam, Birgit Schoeberl. The effect of higher-order receptor clusters on TRAIL induced apoptotic signaling. [abstract]. In: Proceedings of the AACR Special Conference on Computational and Systems Biology of Cancer; Feb 8-11 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 2):Abstract nr B1-29.

Fractional killing arises from cell-to-cell variability in overcoming a caspase activity threshold

When cells are exposed to death ligands such as TRAIL, a fraction undergoes apoptosis and a fraction survives; if surviving cells are re-exposed to TRAIL, fractional killing is once again observed. Therapeutic antibodies directed against TRAIL receptors also cause fractional killing, even at saturating concentrations, limiting their effectiveness. Fractional killing arises from cell-to-cell fluctuations in protein levels (extrinsic noise), but how this results in a clean bifurcation between life and death remains unclear. In this paper, we identify a threshold in the rate and timing of initiator caspase activation that distinguishes cells that live from those that die; by mapping this threshold, we can predict fractional killing of cells exposed to natural and synthetic agonists alone or in combination with sensitizing drugs such as bortezomib. A phenomenological model of the threshold also quantifies the contributions of two resistance genes (c-FLIP and Bcl-2), providing new insight into the control of cell fate by opposing pro-death and pro-survival proteins and suggesting new criteria for evaluating the efficacy of therapeutic TRAIL receptor agonists.

Clinical trials: the viewpoint of children with a chronic illness compared with healthy children

The views of over 200 children (11-16 years old, who were either healthy or attending paediatric medical clinics with a chronic illness) on issues relating to paediatric clinical trials were determined by a questionnaire. Children with a chronic illness had a better understanding of the concept of dosing of medicines (40% vs 23%) and placebo (34% vs 20%). They were more likely to support children's involvement in clinical trials (51% vs 37%). The altruistic nature of children in both groups was similar. It was of concern, however, that 57-63% children would participate as healthy volunteers in a cancer drug trial. Both groups were able to differentiate between the different types of illnesses where it is appropriate to study medicines in children (86-89% for illness where there is no treatment; 34-40% for 'me-too' drugs). Young people should be given more opportunities to be involved in decision-making regarding clinical trials of medicines.

Safety in paediatric clinical trials--a 7-year review

AIM

The safety of clinical trials in children has not been previously studied. We aimed to identify how safety is monitored and the extent of adverse drug reactions (ADRs).

METHODS

A literature review of the Medline Database for therapeutic clinical trials involving oral and intravenous medicines in children from 1996 to 2002. Papers were read to determine the safety monitoring and the presence of adverse events (AEs) or ADRs.

RESULTS

Seven hundred thirty-nine trials were identified. Thirteen (2%) had safety monitoring committees (SMCs). Five hundred twenty-three (71%) trials reported AEs and 151 (20%) of these trials reported a serious AE. ADRs were present in 270 (36.5%) trials, with 80 (11%) of trials having a moderate or severe ADR. Six clinical trials were terminated early because of significant drug toxicity. All of these had SMCs. There were deaths in 83 (11%) trials. In the majority of trials, mortality was thought to be unrelated to the investigational drug; however, in two trials mortality was higher in the treatment group.

CONCLUSIONS

About 11% of trials have a moderate or severe ADR. All paediatric clinical trials should have a SMC.

Clinical trials: the viewpoint of children

The views of 30 children (8-16 years old) attending paediatric medical clinics on paediatric clinical trials were determined by semi-structured interviews. Nineteen children recognised that there were risks involved with taking part in clinical trials. Risks concerned with being paid were recognised by all children.

Engineering and public health at CDC

Engineering is the application of scientific and technical knowledge to solve human problems. Using imagination, judgment, and reasoning to apply science, technology, mathematics, and practical experience, engineers develop the design, production, and operation of useful objects or processes. During the 1940s, engineers dominated the ranks of CDC scientists. In fact, the first CDC director, Assistant Surgeon General Mark Hollis, was an engineer. CDC engineers were involved in malaria control through the elimination of standing water. Eventually the CDC mission expanded to include prevention and control of dengue, typhus, and other communicable diseases. The development of chlorination, water filtration, and sewage treatment were crucial to preventing waterborne illness. Beginning in the 1950s, CDC engineers began their work to improve public health while developing the fields of environmental health, industrial hygiene, and control of air pollution. Engineering disciplines represented at CDC today include biomedical, civil, chemical, electrical, industrial, mechanical, mining, and safety engineering. Most CDC engineers are located in the National Institute for Occupational Safety and Health (NIOSH) and the Agency for Toxic Substances and Disease Registry (ATSDR). Engineering research at CDC has a broad stakeholder base. With the cooperation of industry, labor, trade associations, and other stakeholders and partners, current work includes studies of air contaminants, mining, safety, physical agents, ergonomics, and environmental hazards. Engineering solutions remain a cornerstone of the traditional "hierarchy of controls" approach to reducing public health hazards.

An exceptionally bright flare from SGR 1806–20 and the origins of short-duration γ-ray bursts

Soft-gamma-ray repeaters (SGRs) are galactic X-ray stars that emit numerous short-duration (about 0.1 s) bursts of hard X-rays during sporadic active periods. They are thought to be magnetars: strongly magnetized neutron stars with emissions powered by the dissipation of magnetic energy. Here we report the detection of a long (380 s) giant flare from SGR 1806-20, which was much more luminous than any previous transient event observed in our Galaxy. (In the first 0.2 s, the flare released as much energy as the Sun radiates in a quarter of a million years.) Its power can be explained by a catastrophic instability involving global crust failure and magnetic reconnection on a magnetar, with possible large-scale untwisting of magnetic field lines outside the star. From a great distance this event would appear to be a short-duration, hard-spectrum cosmic gamma-ray burst. At least a significant fraction of the mysterious short-duration gamma-ray bursts may therefore come from extragalactic magnetars.

Hysteroscopic sterilisation: a study of women's attitudes to a novel procedure

Laparoscopy is the most common mode of surgery for female tubal sterilisation. Hysteroscopic sterilisation is a new method which can be performed in the outpatient setting under local anaesthetic. We carried out a prospective cohort trial to determine whether women would actually favour hysteroscopic sterilisation over laparoscopic sterilisation. Data analysis in a cohort of 96 women showed that 77% would prefer laparoscopic sterilisation over the hysteroscopic procedure (23%), despite the advantages of an outpatient setting. Age, obstetric history, employment and marital status, access to transport and previous anaesthetic did not significantly influence the choice made.

A qualitative study of medication-taking behaviour in primary care

BACKGROUND

Prescribed medication is a mainstay of primary care but it is clear that a large proportion of treatment is not taken correctly. Such 'non-compliance' is considered to be a major problem, but research to date has provided few solutions. There have been increasing calls for a change in approach in order to gain a deeper understanding of why the problem remains and new ways of addressing it.

OBJECTIVES

We aimed to investigate how adult primary care patients perceived medication-taking using a Grounded Theory methodology.

METHOD

Fifty general practice patients without major current mental health or recreational drug abuse problems were interviewed at home using a flexible interview schedule. Subjects' accounts of taking prescribed treatments were verified where possible by tablet counts or case-record review, six interviews being excluded as unreliable. Medication use was discussed for 159 prescribed treatments of which 34 were reportedly not taken as directed.

RESULTS

The analysis is presented as a model of decision making which suggests that: (i) knowledge (about disease and treatment) combined with faith in the doctor produces the motivation to start using medicines; (ii) most patients test a medicine before accepting it fully; (iii) three types of medicine user exist: those who (a) passively accept treatment advice, i.e. try to take the medicine as they perceive the doctor wants them to, (b) actively use medicines, i.e. take it as they decide they want to, and (c) reject medication altogether; (iv) the process of accepting a treatment is closely linked to accepting the illness; and (v) practical problems are a late obstacle which only play a small part in the process.

CONCLUSIONS

These concepts have been organized within a comprehensive model of the decision-making process, which is discussed with reference to other current theories of medication use. Researchers and clinicians must move beyond compliance when assessing or trying to improve medication use. Making the medication-testing process explicit is proposed as one way of assisting patients to use treatments better.

Multiple mycotic pseudoaneurysms due to Yersinia enterocolitica: report of a case and review of the literature

The etiology of mycotic aneurysms is variable but most often includes streptococci, staphylococci, Salmonella, and Pseudomonas infections. Yersinia enterocolitica is an organism that has been infrequently associated with vascular infections. We report a case of two ruptured mycotic pseudoaneurysms occurring in the same patient in the superficial femoral artery and the infrarenal abdominal aorta only 10 days apart. The literature is reviewed, and the clinical findings and pathology are discussed. The unique problem of multiple mycotic aneurysms developing at different times as a result of Yersinia bacteremia suggests the need to monitor these patients longitudinally and evaluate multiple sites on the arterial tree to detect occult pseudoaneurysms and prevent late death from rupture.

Portfolio-based learning and general practice vocational training

This action research project developed a portfolio-based learning system, based around a 'log dairy,' with the trainers and general practitioner registrars of one training region in the UK. For those that found benefit from the system, the diary became an important way of holding all the events of a training year together; a way of looking back, in order to view the progress made, and looking forward, to view potential learning needs. Such portfolios were not found to be effective formal assessment mechanisms because the threat of assessment influenced the type of material collected. The enthusiasm of trainers was crucial in encouraging use of the model. The action research process was fundamental in stimulating explorations of ideas on reflective learning. There remains some resistance to the idea of reflective writing, and in this context, portfolios may be one educational tool for use by some, but which may not be universally applicable. Their development and implementation requires considerable local support through facilitation.

Gastrointestinal complications following cardiac surgery

This study sought to determine which factors influence the mortality rate in patients developing gastrointestinal complications following cardiac surgery. Between July 1988 and January 1992, 2054 patients underwent cardiac surgical procedures at the Boston University Medical Center. Of these, 29 (1.4%) developed postoperative gastrointestinal complications. The overall mortality rate among these patients was 27% (8/29). Those who died following such complications had a higher incidence of New York Heart Association (NYHA) class IV and unstable symptoms (8/8, 100% versus 3/21, 14%; P < 0.0001), and an increased need for preoperative intra-aortic balloon pump support (4/8, 50% versus 1/21, 5%; P < 0.004). The need for gastrointestinal surgical intervention increased the mortality rate significantly compared with patients managed medically (8/18, 44% versus 0/11, 0%; P < 0.01). Patients with ischemic bowel also had a significantly higher mortality (5/5, 100% versus 3/24, 12%; P < 0.001). It is concluded that most patients with gastrointestinal complications following cardiac surgery can be treated, and with acceptable mortality rates. The presence of unstable symptoms, preoperative intra-aortic balloon pump support, ischemic bowel and the need for gastrointestinal surgical intervention adversely affect mortality.

The Yohkoh Mission for High-Energy Solar Physics

The Japanese Yohkoh satellite is now in orbit observing the sun with a set of x-ray imagers and x-ray and gamma-ray spectrometers. The data from this successful mission provide new information on solar flares and the sun's corona. This paper discusses the Yohkoh observations and presents a sample of the first scientific results from the mission.

Pituitary tumor volume as a predictor of postoperative visual field recovery. Quantitative analysis using automated static perimetry and computed tomography morphometry

We attempted to define the relationship between the volume of pituitary adenomas and postoperative visual field recovery. Fourteen consecutive patients (27 eyes) were studied who presented with visual complaints and who were confirmed to have pituitary macroadenomas at the time of resection. For each eye, preoperative visual field loss in each quadrant as well as whole field loss were analyzed. Tumor volume was determined from computed tomography scans by summing serial axial sections. Statistically significant correlations (p less than 0.05) of preoperative superonasal and whole visual field loss with tumor volume were found. Postoperative visual field recovery was determined for each patient by subtracting the postoperative visual field loss from the preoperative field loss. Postoperative inferonasal field recovery was significantly correlated (p less than 0.01) with whole tumor volume, with markedly greater recovery in patients with tumor volumes of 5 cc or less. In general, tumor volume proved to be a poor predictor of postoperative visual field recovery.

Effect of retinol and retinoic acid on permeability, electrical resistance and phase transition of lipid bilayers

Retinol and retinoic acid have been incorporated into the artificial membrane systems, planar bimolecular lipid membranes and liposomes, and their effects on several membrane parameters have been measured. 1. Retinol and retinoic acid increased the permeability of egg lecithin liposomes to K+, I- and glucose when incorporated into the membranes at levels as low as 0.5 membrane mol%. Retinoic acid influenced permeability more than did retinol for each of the solutes tested. 2. Retinol and retinoic acid both decreased the electrical resistance of egg lecithin-planar bimolecular lipid membranes from 0.5 to 8 membrane mol%. Retinoic acid effected a larger change than did retinol. 3. Retinol and retinoic acid increased the permeability of dimyristoylphosphatidylcholine and dipalmitoylphosphatidylcholine liposomes to water at 1.0 and 3.0 membrane mol%. A larger effect on water permeability was measured for retinoic acid than for retinol. 4. Retinol and retinoic acid at 1.0 and 3.0 membrane mol% were shown to lower the phase-transition temperature of liposomes composed of dimyristoylphosphatidylcholine or dipalmitoylphosphatidylcholine. Phase-transition temperatures were monitored by abrupt changes in water permeability and liposome size associated with the transition. Retinoic acid lowered the phase-transition temperature of dimyristoylphosphatidylcholine liposomes more than did retinol, while both retinoids had almost the same effect on dipalmitoylphosphatidylcholine liposomes.

Birth centre confinement at the Queen Victoria Medical Centre. I. Obstetric and neonatal outcome

A review of hte first 175 confinements at the Queen Victoria Medical Centre Birth Centre is presented. The design, structure and function of hte Birth Centre is described and the safety of the programme demonstrated. Seventy-four pregnancies (42%) accepted for Birth Centre confinement required transfer because of antepartum or intrapartum complications. There were satisfactory obstetric and neonatal outcomes in all pregnancies. The first year's experience has allowed a reassessment of the risk factors, which will permit greater use of the Birth Centre without any increases risk to mothers or babies.