IRP commission: sexual minorities and mental health: global perspectives

Sexual orientation is a key determinant of the identity of human beings. It has also been seen as a social determinant of health. People whose sexual orientation is non-heterosexual or sexual minorities or sexually diverse are included in the broad umbrella term LGBT (Lesbian, Gay, Bisexual, and Transgender) which is a commonly used acronym in activism, social policy, and subsequently cultural literature. For this reason, this Commission focuses primarily on sexual orientation i.e. lesbian, gay and bisexual (LGB) groups. We have used terms non-heterosexual, sexual minorities or sexual variation interchangeably. We have not considered asexual individuals as research in the field is too limited. We are cognisant of the fact that topics relating to mental health and sexual orientation discussed in this Commission will intersect with other issues of personal, cultural and social identity, and will thus be relevant to individuals including many transgender individuals. The inclusion of mental health issues relevant to gender-diverse individuals as well as gender identity is important and deserves its own separate detailed discussion. The exact number of sexually diverse individuals in a population is often difficult to estimate but is likely to be somewhere around 5% of the population. Rates of various psychiatry disorders and suicidal ideation and acts of suicide in LGB populations are higher than general population and these have been attributed to minority stress hypothesis. Elimination of inequality in law can lead to reduction in psychiatric morbidity in these groups. However, these are all diverse groups but even within each group there is diversity and each individual has a distinct and unique experiences, upbringing, responses to their own sexual orientation, and generating varying responses from families, peers and friends as well as communities (including healthcare professionals). The mental healthcare needs of sexual minority individuals vary and these variations must be taken into account in design, development and delivery of healthcare and policies. Improving access to services will help engagement and outcomes and also reduce stigma. The commission recommends that there is no role for so-called conversion therapies and other recommendations are made for clinicians, researchers and policymakers.

LGBT adolescents in America: Depression, discrimination and suicide

Introduction

The mental health of Adolescents in America is a major concern for the field of psychiatry. In particular, Lesbian, Gay, Bisexual and Transgender (LGBT) adolescents are at higher risk of adverse mental health outcomes. This is largely attributed to “minority stress” and from outright bullying and discrimination. In this presentation, this link between bullying and depression will be explored.

Objectives

By the end of this presentation, the audience will be able to better understand the link between anti-LGBT bullying and mental illness and identify the ways to help their patients.

Methods

This presentation is informed by a literature search from PubMed In addition, it is informed by a symposium previously done at the American Psychiatric Association (APA) annual meeting in 2014.

Results

There is clear evidence in the literature that bullying of LGBT adolescents is pervasive. In addition, LGBT people are more likely to be depressed than their heterosexual counterparts. This combination has led to 4-5 times higher rates of attempted suicide by LGBT adolescents. Having Gay-Straight Alliances in schools, supportive teachers and school administrators, and broader anti-discrimination legislation has a protective effect on this.

Conclusion

LGBT adolescents are exposed to more stress by being a minority in society and by being explicitly bullied and discriminated against. This can lead to depression in some of these adolescents, and can also lead to suicide in the most vulnerable among them. There are proven ways to reduce these risks, and psychiatrists have a role to play in advocating for these reforms.

Disclosure of interest

The author has not supplied his declaration of competing interest.

Proton-driven plasma wakefield acceleration in AWAKE

In this article, we briefly summarize the experiments performed during the first run of the Advanced Wakefield Experiment, AWAKE, at CERN (European Organization for Nuclear Research). The final goal of AWAKE Run 1 (2013-2018) was to demonstrate that 10-20 MeV electrons can be accelerated to GeV energies in a plasma wakefield driven by a highly relativistic self-modulated proton bunch. We describe the experiment, outline the measurement concept and present first results. Last, we outline our plans for the future. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

Experimental Observation of Proton Bunch Modulation in a Plasma at Varying Plasma Densities

We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch. The modulation extends over the length of the proton bunch following the seed point. By varying the plasma density over one order of magnitude, we show that the modulation frequency scales with the expected dependence on the plasma density, i.e., it is equal to the plasma frequency, as expected from theory.

Experimental Observation of Plasma Wakefield Growth Driven by the Seeded Self-Modulation of a Proton Bunch

We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1×10^{14} and 7.7×10^{14}  electrons/cm^{3}. We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (<15  MV/m) and reach over 300  MV/m. All these results confirm the development of the seeded self-modulation process, a necessary condition for external injection of low energy and acceleration of electrons to multi-GeV energy levels.

Acceleration of electrons in the plasma wakefield of a proton bunch

High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration^1–5, in which the electrons in a plasma are excited, leading to strong electric fields (so called ‘wakefields’), is one such promising acceleration technique. Experiments have shown that an intense laser pulse^6–9 or electron bunch^10,11 traversing a plasma can drive electric fields of tens of gigavolts per metre and above—well beyond those achieved in conventional radio-frequency accelerators (about 0.1 gigavolt per metre). However, the low stored energy of laser pulses and electron bunches means that multiple acceleration stages are needed to reach very high particle energies^5,12. The use of proton bunches is compelling because they have the potential to drive wakefields and to accelerate electrons to high energy in a single acceleration stage¹³. Long, thin proton bunches can be used because they undergo a process called self-modulation^14–16, a particle–plasma interaction that splits the bunch longitudinally into a series of high-density microbunches, which then act resonantly to create large wakefields. The Advanced Wakefield (AWAKE) experiment at CERN^17–19 uses high-intensity proton bunches—in which each proton has an energy of 400 gigaelectronvolts, resulting in a total bunch energy of 19 kilojoules—to drive a wakefield in a ten-metre-long plasma. Electron bunches are then injected into this wakefield. Here we present measurements of electrons accelerated up to two gigaelectronvolts at the AWAKE experiment, in a demonstration of proton-driven plasma wakefield acceleration. Measurements were conducted under various plasma conditions and the acceleration was found to be consistent and reliable. The potential for this scheme to produce very high-energy electron bunches in a single accelerating stage²⁰ means that our results are an important step towards the development of future high-energy particle accelerators^21,22.

Electron acceleration to very high energies is achieved in a single step by injecting electrons into a ‘wake’ of charge created in a 10-metre-long plasma by speeding long proton bunches.

Roles of "Wanting" and "Liking" in Motivating Behavior: Gambling, Food, and Drug Addictions

The motivation to seek out and consume rewards has evolutionarily been driven by the urge to fulfill physiological needs. However in a modern society dominated more by plenty than scarcity, we tend to think of motivation as fueled by the search for pleasure. Here, we argue that two separate but interconnected subcortical and unconscious processes direct motivation: "wanting" and "liking." These two psychological and neuronal processes and their related brain structures typically work together, but can become dissociated, particularly in cases of addiction. In drug addiction, for example, repeated consumption of addictive drugs sensitizes the mesolimbic dopamine system, the primary component of the "wanting" system, resulting in excessive "wanting" for drugs and their cues. This sensitizing process is long-lasting and occurs independently of the "liking" system, which typically remains unchanged or may develop a blunted pleasure response to the drug. The result is excessive drug-taking despite minimal pleasure and intense cue-triggered craving that may promote relapse long after detoxification. Here, we describe the roles of "liking" and "wanting" in general motivation and review recent evidence for a dissociation of "liking" and "wanting" in drug addiction, known as the incentive sensitization theory (Robinson and Berridge 1993). We also make the case that sensitization of the "wanting" system and the resulting dissociation of "liking" and "wanting" occurs in both gambling disorder and food addiction.

Primary hepatic angiosarcoma

Primary hepatic angiosarcoma is a rare, aggressive tumor; composed of spindle or pleomorphic cells that line, or grow into, the lumina of pre-existing vascular spaces like sinusoids and terminal hepatic venules; with only about 200 cases diagnosed annually worldwide but it is the most common primary malignant mesenchymal tumor of the liver in adults and accounts for 2% of all primary hepatic malignancies. HAS occurs in association with known chemical carcinogens, but 75% of the tumors have no known etiology. Patients present with vague symptoms like abdominal pain, weight loss, fatigue or an abdominal mass. Hepatic angiosarcoma is usually multicentric and involves both lobes, entire liver may also found to be involved. CD31 is the most reliable marker. These tumors lack specific features on imaging, so, pathological diagnosis is necessary. There are no established treatment guidelines because of low frequency and aggressive nature of tumor, chemotherapy is only palliative, liver resection is indicated for solitary mass and liver transplant is contraindicated. The aim of this article is to comprehensively review all the available literature and to present detailed information and an update on primary hepatic angiosarcoma.

Performance analysis of newly developed point-of-care hemoglobinometer (TrueHb) against an automated hematology analyzer (Sysmex XT 1800i) in terms of precision in hemoglobin measurement

INTRODUCTION

The aim of this study was to evaluate the performance of the newly developed handheld hemoglobinmeter (TrueHb) by comparing its performance against and an automated five-part hematology analyzer, Sysmex counter XT 1800i (Sysmex).

METHODS

Two hundred venous blood samples were subjected through their total hemoglobin evaluation on each device three times. The average of the three readings on each device was considered as their respective device values, that is, TrueHb values and Sysmex values. The two set of values were comparatively analyzed. The repeatability of the performance of TrueHb was also evaluated against Sysmex values.

RESULTS

The scatter plot of TrueHb values and Sysmex values showed linear distribution with positive correlations (r = 0.99). The intraclass correlation (ICC) values between the two set of values was found to be 0.995. Regression coefficients through origin, β, was found to be 0.995, with 95% confidence intervals (CI) ranging between 0.9900 and 1.0000. The mean difference in Bland-Altman plots of TrueHb values against the Sysmex values was found to be -0.02, with limits of agreement between -0.777 and 0.732 g/dL. Statistical analysis suggested good repeatability in results of TrueHb, having a low mean CV of 2.22, against 4.44, that of Sysmex values, and 95% confidence interval of 1.99-2.44, against 3.85-5.03, that of Sysmex values.

CONCLUSION

These results suggested a strong positive correlation between the two measurements devices. It is thus concluded that TrueHb is a good point-of-care testing tool for estimating hemoglobin.

Idiopathic collapsing glomerulopathy: A clinicopathologic analysis of 30 cases

Collapsing glomerulopathy (CG) is a distinct clinicopathologic entity associated with various infections, medications and acute ischemia. There have been few scattered reports of CG from India. This study aimed at evaluating the clinicopathologic features of idiopathic CG in Indian patients with comparison between adult-onset and childhood CG. This study included all cases of idiopathic CG diagnosed over a period of 4 years (2006-2009). Appropriate clinical details and laboratory findings were retrieved. Renal biopsies were reviewed and detailed pathologic features assessed. Statistical analysis was performed to compare various features between adult-onset and childhood CG. Over these 4 years, 30 cases of idiopathic CG were diagnosed. Of these, 11 were children. Childhood CG cases had longer duration of symptoms and lower serum urea and creatinine levels compared with adult patients. In renal histology, tubular atrophy and interstitial fibrosis was frequent in our cases. Pediatric cases of CG showed a higher proportion of segmental glomerulosclerosis. On clinical follow-up, nine of the 30 patients progressed to end-stage renal disease and these included two pediatric patients. Idiopathic CG is a significant cause of renal dysfunction in both pediatric and adult patients. Childhood and adult-onset CG differ in few clinicopathologic features. Early and accurate diagnosis of CG is imperative for appropriate management of these patients.

Detection of subclinical peste des petits ruminants virus infection in experimental cattle

The present study was undertaken to investigate the possible involvement of cattle in the epidemiology of peste des petits ruminants (PPR) as subclinical carriers. Cattle were exposed experimentally to PPR virus (PPRV) infection or placed in contact with PPR infected goats. Clinical samples including heparinized/EDTA blood, plasma, peripheral blood monocyte cells (PBMCs) and clotted blood (for serum) were collected periodically from 21 days post infection (dpi) to 397 dpi (21, 45, 50, 57, 65, 95, 111, 119, 148, 190, 203 and 397 dpi) and tested for PPRV antigen, nucleic acid and antibody. Exposed cattle seroconverted and maintained PPRV specific haemagglutinin antibodies and detectable PPRV antigen/nucleic acid in blood, plasma and PBMCs from 21 to 397 dpi. PPRV was recovered from blood and PBMC collected from experimental animals at 21 dpi, initially in B95a cells and then adapted to Vero cells. The study indicated that PPRV can infect cattle subclinically and PPRV antigen/nucleic acid persist in cattle for at least 397 days.

Detection of New Delhi metallo-beta-lactamase and extended-spectrum beta-lactamase genes in Escherichia coli isolated from mastitic milk samples

In this study, eight Escherichia coli isolates were obtained from milk samples of dairy cattle suffering from clinical/subclinical mastitis. Isolates were characterized for antimicrobial resistance traits and virulence genes. Results revealed that one isolate was harbouring New Delhi metallo-beta-lactamase gene (blaNDM ). Cloning and sequencing of the PCR amplicon confirmed the identity of the gene (GenBank accession no. KC769583) having 100% homology with blaNDM-5 (GenBank accession no. JN104597.1), and this isolate was susceptible to colistin, chloramphenicol and tetracycline only. Moreover, another isolate carried extended-spectrum beta-lactamase (ESBL) gene - blaCTX-M , and all isolates possessed blaTEM gene. Of the eight isolates, only one isolate was positive for shiga toxin gene (stx2), and none were harbouring stx1 gene. Occurrence of New Delhi metallo-beta-lactamase (blaNDM ) in one E. coli isolate and ESBL genes in other isolates poses a potential threat to human health following possible entry and spread through food chain.

Prokaryotic expression and purification of highly soluble partial glycoprotein erns of Indian strain of classical Swine Fever virus

Classical swine fever (CSF) or hog cholera, caused by a positive stranded RNA virus belonging to the genus Pestivirus of the Flaviviridae family, is highly contagious and fatal disease of pigs. We report the novel design of construct for production of highly soluble glycoprotein Erns fragment using prokaryotic expression system. A truncated fragment of the Erns gene (coding for aa 109-170) denoted as 'Erns-Ag' was subcloned and expressed as hexa-histidine tag fusion on both terminus of protein in Escherichia coli. The highly soluble recombinant Erns-Ag protein with purity >95 % was purified by one step Ni-NTA affinity chromatography under native condition. Anti Erns-Ag polyclonal antibodies raised in guinea pig was found to react with CSFV antigen in infected MDCK cell line during immunoperoxidase test. The described methodology of producing a highly soluble recombinant protein with native conformation would likely to assist in development of differential diagnostic test as well as its application in raising hyperimmune sera for detection of CSFV antigen either in tissue materials or infected cell lines.

A phase II study of concurrent cetuximab-cisplatin and intensity-modulated radiotherapy in locoregionally advanced nasopharyngeal carcinoma

BACKGROUND

Based on our previous work on the clinical activity of cetuximab in recurrent nasopharyngeal carcinoma (NPC), we evaluated the feasibility of adding cetuximab to concurrent cisplatin and intensity-modulated radiotherapy (IMRT) in locoregionally advanced NPC.

PATIENTS AND METHODS

Patients with American Joint Committee on Cancer stage III-IVB NPC were given an initial dose of cetuximab (400 mg/m(2)) 7-10 days before receiving concurrent IMRT, weekly cisplatin (30 mg/m(2)/week) and cetuximab (250 mg/m(2)/week).

RESULTS

Thirty patients (median age of 45 years) with stage III (67%), IVA (30%) and IVB (3%) nonkeratinizing NPC were enrolled. Grade 3-4 oropharyngeal mucositis occurred in 26 (87%) patients and 10 (33%) patients required short-term nasogastric feeding. Grade 3 radiotherapy-related dermatitis occurred in six patients (20%) and three patients (10%) had grade 3 cetuximab-related acneiform rash. These grade 3-4 skin and mucosal toxic effects were manageable and reversible. At a median follow-up of 31.8 months [95% confidence interval (CI) 26.2-32.1 months], the 2-year progression-free survival was 86.5% (95% CI 74.3% to 98.8%).

CONCLUSIONS

Concurrent administration of cetuximab, weekly cisplatin and IMRT is a feasible strategy against locoregionally advanced NPC. Preliminary survival data compare favorably with historic data and further follow-up is warranted.

DNA triplex-mediated inhibition of MET leads to cell death and tumor regression in hepatoma

Mesenchymal epithelial transition factor (MET) is one of the critical cell signaling molecules whose aberrant expression is reported in several human cancers. The aim of the study is to investigate the antigene and antiproliferative effect of short triplex forming oligonucleotides, TFO-1 (part of the positive regulatory element) and TFO-2 (away from the transcription start site) on MET expression. HepG2 cells transfected only with TFO-1 (but not with TFO-2 and non-specific TFO) significantly decreased MET levels, which is accompanied by decrease in antiapoptotic proteins and increase in pro-apoptotic proteins. Phosphoproteome-array analysis of 46 intracellular kinases revealed hypophosphorylation of about 15 kinases including ERK, AKT, Src and MEK, suggesting the growth inhibitory effect of TFO-1. Further, the efficacy of TFO-1 was tested on diethylnitrosamine-induced liver tumors in wistar rats. T2-weighted magnetic resonance imaging showed decrease in liver tumor volume up to 90% after treatment with TFO-1. Decreased MET expression and elevated apoptotic activity further indicate that TFO-1 targeted to c-met leads to cell death and tumor regression in hepatoma. Formation of stable DNA triplex between TFO-1 and targeted gene sequence was confirmed by circular dichroic spectroscopy and gel retardation assay. Therefore, it can be concluded that DNA triplex-based therapeutic approaches hold promise in the treatment of malignancies associated with MET overexpression.

Prevalence of classical swine fever virus in India: a 6-year study (2004-2010)

A study was undertaken regarding the prevalence of classical swine fever virus (CSFV) antibodies and antigens in sera and suspected tissue samples of domestic pigs. The samples were received between January 2004 and September 2010. A total of 594 serum samples from 12 states and 287 tissue samples from 13 states of India were tested using commercial enzyme-linked immunosorbent assay (ELISA) kits. The mean prevalence of CSFV antibodies in suspected sera was 63.3% (376/594), whereas 76.7% (220/287) of the suspected samples were found to contain CSFV antigen. The high prevalence of CSFV antibodies suggests that the disease is endemic in the country. This baseline data will be of use in the formulation of control and eradication programmes.

Development, characterization and in vitro assessement of stearylamine-based lipid nanoparticles of paclitaxel

The objective of the study was to design and evaluate a solid lipid nanoparticle (SLN) drug delivery system for delivery of paclitaxel. Components of the SLN were lipid (stearylamine) and surfactants (Pluronic F68 and Soya lecithin). The paclitaxel loaded nanoparticles were prepared by a modified solvent injection method. Experiments were carried out with excipients, where surfactants, lipid and drug molar ratios were varied to optimize the formulation characteristics. The in vitro drug release profile from the nanoparticles followed a diffusion controlled mechanism. The modified solvent injection method ensured high entrapment efficiency (approximately 75%), produced smaller, stable nanoparticles with a narrow size distribution and proved to be a reproducible and fast production method. The present study describes the feasibility and suitability of stearylamine based SLN produced using a mixture of surfactants to develop a clinically useful system with targeting potential for poorly soluble antineoplastic drugs.

Effect of altitude on picroside content in core collections of Picrorhiza kurrooa from the north western Himalayas

Picrorhiza kurrooa Royle ex Benth (Scrophulariaceae), commonly known as Kutki, is a major ingredient of many ayurvedic preparations prescribed in the treatment of various diseases. Picrosides I and II are the active agents responsible for the medicinal effects of Kutki, and the variation in content of these compounds in plants at different altitudes is a major question to be addressed. The picroside I and II content in various plant parts of P. kurrooa collected from different altitudes, viz. Sonemarg (2,740 m a.s.l.), Tangmarg (2,690 m a.s.l.), and Pulwama (1,630 m a.s.l.) in the north-western Kashmir Himalayas was analyzed by HPLC. A considerable degree of variation in picroside content was observed. Picroside I and II was highest in populations collected from Sonemarg followed by Tangmarg, suggesting that picroside accumulation is directly correlated with altitudinal change. More picroside I was found in the rhizome and roots of the Pulwama population as compared to Tangmarg samples, whereas the quantity of Picroside II was reduced in plants from Pulwama compared to the Tangmarg population, suggesting that cultivation of P. kurroa at lower altitude reduces the picroside content. The quantities of picrosides also varied spatially, being highest in rhizome followed by roots, inflorescence and leaves in the populations from all three locations. The study concludes that picroside I and II accumulation depends on altitude, which could help in the selection and collection of superior genotypes with uniform effects for utilization by the pharmaceutical industry.

Preparation, characterization, and in vitro antimicrobial assessment of nanocarrier based formulation of nadifloxacin for acne treatment

The objective of the present study was to develop a nanocarrier based formulation of nadifloxacin and to investigate its in vitro antimicrobial effect against Propionibacterium acnes. Nanocarrier based microemulsion formulations were prepared by aqueous titration method, using oleic acid as oil phase, Tween-80 as surfactant and ethanol as co-surfactant in different ratios. This procedure yielded monodisperse microemulsions exhibiting a mean droplet size in the range of 95-560 nm. This range of particle size is good to treat follicle related disorders like acne vulgaris because the size of follicles is in the range of 50-100 microm. Furthermore the optimized formulations were characterized for surface morphology by transmission electron microscopy and refractive index. The permeation studies were carried out using rat skin mounted in Franz diffusion cells. Flux of the optimised formulation was 2.24 times that of control. The diameter of inhibition zone of the microemulsion was found good but smaller than that of a clindamycin disc because of the higher therapeutic efficacy of clindamycin against P. acnes. The results indicated that the developed microemulsion shows promising results against P. acnes bacteria and may be a good approach for acne treatment.

Approach to blood donors with microcytosis

The aim of this paper is to find microcytosis in donors, to establish prevalence of iron deficiency anaemia (IDA) and beta-thalassemia trait (BTT) in them and to evaluate which index is most effective in differentiating these two conditions. IDA and BTT are the most common causes of microcytic anaemia. Traditional approach is trial of iron treatment. Where thalassemias are common, this can lead to iron overload and failure to provide diagnosis/counselling in BTT. Initially 925 donor samples were evaluated on cell counter. Of these, 50 were found microcytic. These were subjected to Ferritin and HbA2 determination. Subsequently, additional 51, age- and sex-matched normocytic donor samples were selected as controls. These were subjected to the same tests. Nine indices namely RBC, RDW, Mentzer's, Shine and Lal, England and Fraser, Srivastava, Green and King, RDW index and Ricerca were used to differentiate IDA and BTT. Prevalence of microcytosis was 5.4%. Of these microcytic samples, 52% were IDA, 36% were BTT, 8% had both and 4% were undiagnosed. IDA had significantly lower Hb, mean corpuscular volume (MCV) and Ferritin levels than the control group. BTT had lower MCV, higher Ferritin and comparable Hb levels with control group. The Youden's index of Mentzer's was highest and RBC was the only index which had both sensitivity and specificity more than 80% for both IDA and BTT. It is desirable to routinely perform hemograms for all blood donors and further analyse the microcytic samples for Ferritin and HbA2 to diagnose IDA and BTT and to provide appropriate counselling/treatment.

Stress echocardiography: risk stratification, prognosis, patient outcomes and cost-effectiveness

The utilization of stress echocardiography has undergone considerable expansion and evolution over the past three decades. Although stress echocardiography was first conceived as a noninvasive diagnostic tool for determining the presence or absence of coronary artery disease (CAD), its prognostic value is now well established. Thus, identification of patients at risk for future cardiac events has become a primary objective in the noninvasive evaluation of patients with chest pain syndromes and among patients with known CAD. In particular, the ability of stress echocardiography to identify patients at low (<1%), intermediate (1-5%) or high (>5%) risk for future cardiac events is essential to patient management decisions. Moreover, previous studies have conclusively demonstrated the incremental prognostic value of stress echocardiography over clinical and treadmill exercise data, in predicting future cardiac events. This review addresses the current role and summarizes current literature with respect to the use of stress echocardiography in determining patient risk for cardiac events and the cost-effective integration of such information into patient management decisions.