Future of service member monitoring: the intersection of biology, wearables and artificial intelligence

While substantial investment has been made in the early identification of mental and behavioural health disorders in service members, rates of depression, substance abuse and suicidality continue to climb. Objective and persistent measures are needed for early identification and treatment of these rising health issues. Considerable potential lies at the intersection of biology, wearables and artificial intelligence to provide high accuracy, objective monitoring of mental and behavioural health in training, operations and healthcare settings. While the current generation of wearable devices has predominantly targeted non-military use cases, military agencies have demonstrated successes in monitoring and diagnosis via off-label uses. Combined with context-aware and individualised algorithms, the integration of wearable data with artificial intelligence allows for a deeper understanding of individual-level and group-level mental and behavioural health at scale. Emerging digital phenotyping approaches which leverage ubiquitous sensing technology can provide monitoring at a greater scale, lower price point and lower individual burden by removing the need for additional body-worn technology. The intersection of this technology will enable individualised strategies to promote service member mental and physical health, reduce injury, and improve long-term well-being and deployability.

PMON214 Kisspeptin Restores Sexual and Attraction Brain Processing in Women with Hypoactive Sexual Desire Disorder

Introduction

Sexual desire is a key component of the sexual response model. Absence or deficiency of sexual desire can lead to marked distress or interpersonal difficulty, termed 'hypoactive sexual desire disorder' (HSDD). HSDD is the most common female sexual health complaint worldwide, affecting 10% of women. Despite its detrimental impact on psychological well-being and quality of life, treatment options are currently limited. The hormone kisspeptin is a key endogenous activator of the reproductive endocrine axis, with emerging roles in sexual and emotional behaviour, and thus could serve as a novel treatment option in women with HSDD.

Hypothesis

Kisspeptin restores sexual brain processing in women with HSDD.

Methods

To test our hypothesis, we performed a randomized, double-blind, two-way crossover, placebo-controlled study in 32 (mean age ± SEM 29.2±1.2 years; BMI 23.1±0.5 kg/m2) premenopausal women with HSDD using psychometric assessments, functional neuroimaging, and hormonal assessments to investigate the effects of kisspeptin administration on brain activity, in response to erotic stimuli (erotic videos) and facial attraction (face images of varying attractiveness). Study visits were undertaken in the early follicular phase of the menstrual cycle.

Results

Kisspeptin administration resulted in an increase in self-reported ratings of feeling 'sexy', compared to placebo, measured using the Sexual Arousal and Desire Inventory (t [32] =2.27, P=0.03). On functional MRI, kisspeptin administration deactivated the left inferior frontal gyrus and activated the postcentral and supramarginal gyrus in response to erotic videos (Z=2.3, P< 0.05). Kisspeptin administration deactivated the secondary somatosensory cortex (Z=2.3, P<0.05) and enhanced activation in the posterior cingulate cortex on viewing male faces, which correlated with a reduction in self-reported sexual aversion (r=0.476, P=0.005). Kisspeptin resulted in a mean increase in LH of 2.75 iU/L (F(1, 62) = 6.084, P=0.02) and FSH of 0.37 iU/L (F(1, 62) = 4.030, P=0.05) across the 75-minute duration of the study, with no effect observed on downstream circulating estradiol, progesterone or testosterone levels.

Interpretation of results and conclusionsDeactivation of the left inferior frontal gyrus by kisspeptin administration likely serves to reduce the internal monologue and response inhibition. Furthermore, kisspeptin's deactivation of the secondary somatosensory cortex can reduce a woman's focus on herself, her body image, and related negative thoughts, thus augmenting her judgement of male facial attractiveness. Finally, kisspeptin's actions in the posterior cingulate cortex can serve to increase feelings of romantic love and reward processing, thereby reducing sexual aversion and increasing sexual desire. Collectively these brain changes provide mechanistic insights for the observed increase in sexual desire and attraction during kisspeptin administration in women with HSDD.

These behavioural and mechanistic findings in women with HSDD lay the foundations for clinical applications for kisspeptin in psychosexual disorders.

Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

RF01 | PMON43 Melanocortin-4 Receptor Agonism Enhances Sexual Brain Processing in Women with Hypoactive Sexual Desire Disorder

Introduction

Hypoactive sexual desire disorder (HSDD) is characterized by a persistent deficiency of sexual fantasies and desire for sexual activity, causing marked distress or interpersonal difficulty. It is the most prevalent female sexual health problem worldwide, affecting approximately 1 in 10 women, but has limited treatment options despite its substantial health, social, and economic burden. Melanocortin-4 receptor (MC4R) agonists have emerged as a promising therapy for women with HSDD, although, to date, their mechanism of action is unknown. This study aims to use functional MRI to delineate the reproductive neuroendocrine pathways involved and elucidate how MC4R agonists treat HSDD in women.

Methods

We conducted a randomized, double-blinded, placebo-controlled, crossover clinical study, using psychometric, functional neuroimaging and hormonal analyses, to assess the effects of MC4R agonism on sexual brain processing in 31 premenopausal women with HSDD. Participants attended on two occasions, receiving either a subcutaneous injection of an MC4R agonist (Bremelanotide 1.75 mg), or placebo, at each study visit, thereby acting as their own controls.

Results

31 randomized women were included (mean age 32 years, mean duration of HSDD 41 months). MC4R agonism significantly increased self-reported sexual desire for up to 24-hours post administration, compared to placebo (P=0.007). During functional neuroimaging, MC4R agonism enhanced cerebellar and supplementary motor area activity, as well as deactivating the secondary somatosensory cortex, specifically in response to visual erotic videos, compared to placebo (Z=2.3, P<0.05). In addition, MC4R agonism enhanced functional connectivity between the amygdala-insula and amygdala-thalamus during prolonged visual erotic stimuli, compared to placebo (P=0.025). MC4R agonism resulted in a mean increase in LH of 1.1 iU/L (F [1,58] = 13.38, P=0.0005), and FSH of 0.35 iU/L (F [1,60] = 10.97, P=0.0016) across the 300-minute duration of the study, with no effect observed on circulating estradiol or progesterone levels.

Interpretation of results and conclusions:We demonstrate that MC4R agonism deactivates the secondary somatosensory cortex which can reduce the detrimental self-monitoring process often observed in HSDD, thereby increasing sexual desire. Furthermore, cerebellar and supplementary motor area activation by MC4R agonism are associated with increased sexual arousal and sexual motor imagery respectively. Finally, MC4R agonism enhanced functional connectivity between key limbic structures which can be disrupted in HSDD.

In summary, these data identify the previously undescribed neural substrates and connections through which MC4R agonism modulates sexual brain processing to increase sexual desire. These findings provide mechanistic insight for the action of MC4R agonism in sexual behaviour and are relevant to ongoing therapeutic development for HSDD and for MC4R agonist development more widely.

Trial registration: ClinicalTrials.gov identifier NCT04179734.Funding: Investigator-sponsored study funded by AMAG Pharmaceuticals Inc, MRC and NIHR.

Presentation: Saturday, June 11, 2022 1:00 p.m. - 1:05 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Brain activity changes associated with pain perception variability

Pain perception can be modulated by several factors. Phenomena like temporal summation leads to increased perceived pain, whereas behavioral conditioning can result in analgesic responses. Furthermore, during repeated, identical noxious stimuli, pain intensity can vary greatly in some individuals. Understanding these variations is important, given the increase in investigations that assume stable baseline pain for accurate response profiles, such as studies of analgesic mechanisms. We utilized functional magnetic resonance imaging to examine the differences in neural circuitry between individuals displaying consistent pain ratings and those who experienced variable pain during a series of identical noxious stimuli. We investigated 63 healthy participants: 31 were assigned to a "consistent" group, and 32 were assigned to a "variable" group dependent on pain rating variability. Variable pain ratings were associated with reduced signal intensity in the dorsolateral prefrontal cortex (dlPFC). Furthermore, the dlPFC connectivity with the primary somatosensory cortex and temperoparietal junction was significantly reduced in variable participants. Our results suggest that investigators should consider variability of baseline pain when investigating pain modulatory paradigms. Additionally, individuals with consistent and variable pain ratings differ in their dlPFC activity and connectivity with pain-sensitive regions during noxious stimulation, possibly reflecting the differences in attentional processing and catastrophizing during pain.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Novel discovery of Extended Spectrum β-lactamase (ESBL) Pluralibacter gergoviae in acute urinary tract infection and urolithiasis

Introduction/Objective

This case study describes the diagnosis, treatment, whole genome sequencing (WGS) and antibiotic resistance characterization from the ESBL-producing Pluralibacter gergoviae, a multi-drug resistant organism (MDRO) with a previously-documented presence in foodstuffs and cosmetics.

Methods/Case Report

A 39-year-old Hispanic American woman was admitted to the emergency department (ED) for fever, suprapubic tenderness, and pyuria. Three days prior to admission, patient underwent elective bilateral lithotripsy for retained nephrolithiasis. Seven days prior to ED admission, patient had an “Orgasm Shot” (O-Shot) which consists of platelet rich plasma that is drawn from the patient and injected into her vulvar area and around her clitoris to increase stimulation potential during orgasm. The patient was started on broad spectrum antibiotics, receiving Vancomycin and Ceftriaxone 1 gram 1 gram IV every 12 hours, intravenously. Urine cultures yielded two organisms, including a lactose fermenting as well as a non-lactose fermenting Gram negative rod. Mass spectrometry-based identification was successful in identifying the non-lactose fermenting colony as Pseudomonas aeruginosa, which also identified from a blood culture collected from the patient upon presentation to the ED. The lactose fermenting colony resulted in no identification by mass spectrometry but was identified using biochemical methods as Pluralibacter gergoviae, a recently-reclassified taxonomy previously identified as Enterobacter gergoviae. The P. gergoviae isolate was submitted to the Multidrug-Resistant Organism Repository (MRSN) at Walter Reed Army Institute of Research (WARIR) for WGS on Illumina Miseq. Sequencing and phenotypic/ genotypic data on isolate confirmed this as an ESBL P. gergoviae organism.

Results (if a Case Study enter NA)

NA

Conclusion

Summary data on possible epidemiological associations, antibiotic susceptibility testing, antibiotic resistance genes identified, and information on the antibiotic resistance plasmids will be presented. These findings from the WGS data, antibiotic susceptibilities will provide a lessons-learned for other clinical microbiology labs on how to identify unusual organisms such as P. gergoviae.

606 AUDIT: IV Fluid Prescribing in Surgical Patients

Aim

A recent change to electronic fluid prescribing has enabled us to evaluate our adherence to recommendations. NICE clinical guideline 174 states that patients should receive 25-30ml/kg/day water and 1mmol/kg/day of sodium, potassium, and chloride with regards to maintenance fluid therapy. We retrospectively audited our practice in surgical patients.

Method

Patients were selected from two surgical inpatient wards in a district general hospital utilising random sampling over a one-month period. Prescribed intravenous fluid (IV) therapy over a 24-hour period was collected; in addition to weight, presence of an acute kidney injury (AKI) and indication for IV replacement (maintenance versus resuscitation).

Results

50 patients were identified during the period. All of them were emergency presentations. Maintenance fluids were prescribed for 76% of patients. No patients had an AKI at time of data collection. The mean weight was 75kg. Overall, patients received a mean fluid volume of 2.3L/day. The mean concentration of electrolytes administered over a 24-hour period were: Sodium 297mmol, Potassium 13mmol, Chloride 237mmol. When adjusting for patient weight, this resulted in a net administration of: Sodium +221mmol, Potassium -62mmol, Chloride +162mmol.

Conclusions

Three quarters of surgical patients were administered maintenance fluids. The electrolyte contents of these fluids were inadequate. Patients received 295% excess Sodium, 216% excess Chloride, and 82% less than the recommended daily requirement of Potassium. We aim to introduce a protocol for maintenance fluid prescribing, in addition to teaching sessions, that would allow for adherence to guidelines and improve patient care.

Thyroid Function Before, During and After COVID-19

Context: The effects of COVID-19 on the thyroid axis remain uncertain. Recent evidence has been conflicting, with both thyrotoxicosis and suppression of thyroid function reported. Objective: We aimed to detail the acute effects of COVID-19 on thyroid function and determine if these effects persisted upon recovery from COVID-19. Design: Cohort observational study. Participants and Setting: Adult patients admitted to Imperial College Healthcare National Health Service Trust, London, UK with suspected COVID-19 between March 9 to April 22, 2020 were included, excluding those with pre-existing thyroid disease and those missing either free thyroxine (FT4) or TSH measurements. Of 456 patients, 334 had COVID-19 and 122 did not. Main Outcome Measures: TSH and FT4 measurements at admission, and where available, those taken in 2019 and at COVID-19 follow-up. Results: Most patients (86·6%) presenting with COVID-19 were euthyroid, with none presenting with overt thyrotoxicosis. Patients with COVID-19 had a lower admission TSH and FT4 compared to those without COVID-19. In the COVID-19 patients with matching baseline thyroid function tests from 2019 (n=185 for TSH and 104 for FT4), both TSH and FT4 were reduced at admission compared to baseline. In a complete cases analysis of COVID-19 patients with TSH measurements at follow-up, admission and baseline (n=55), TSH was seen to recover to baseline at follow-up. Conclusions: Most patients with COVID-19 present with euthyroidism. We observed mild reductions in TSH and FT4 in keeping with a non-thyroidal illness syndrome. Furthermore, in survivors of COVID-19, thyroid function tests at follow-up returned to baseline.

Kisspeptin receptor agonist has therapeutic potential for female reproductive disorders

BACKGROUNDKisspeptin is a key regulator of hypothalamic gonadotropin-releasing hormone (GnRH) neurons and is essential for reproductive health. A specific kisspeptin receptor (KISS1R) agonist could significantly expand the potential clinical utility of therapeutics targeting the kisspeptin pathway. Herein, we investigate the effects of a KISS1R agonist, MVT-602, in healthy women and in women with reproductive disorders.METHODSWe conducted in vivo and in vitro studies to characterize the action of MVT-602 in comparison with native kisspeptin-54 (KP54). We determined the pharmacokinetic and pharmacodynamic properties of MVT-602 (doses 0.01 and 0.03 nmol/kg) versus KP54 (9.6 nmol/kg) in the follicular phase of healthy women (n = 9), and in women with polycystic ovary syndrome (PCOS; n = 6) or hypothalamic amenorrhea (HA; n = 6). Further, we investigated their effects on KISS1R-mediated inositol monophosphate (IP1) and Ca2+ signaling in cell lines and on action potential firing of GnRH neurons in brain slices.RESULTSIn healthy women, the amplitude of luteinizing hormone (LH) rise was similar to that after KP54, but peaked later (21.4 vs. 4.7 hours; P = 0.0002), with correspondingly increased AUC of LH exposure (169.0 vs. 38.5 IU∙h/L; P = 0.0058). LH increases following MVT-602 were similar in PCOS and healthy women, but advanced in HA (P = 0.004). In keeping with the clinical data, MVT-602 induced more potent signaling of KISS1R-mediated IP1 accumulation and a longer duration of GnRH neuron firing than KP54 (115 vs. 55 minutes; P = 0.0012).CONCLUSIONTaken together, these clinical and mechanistic data identify MVT-602 as having considerable therapeutic potential for the treatment of female reproductive disorders.TRIAL REGISTRATIONInternational Standard Randomised Controlled Trial Number (ISRCTN) Registry, ISRCTN21681316.FUNDINGNational Institute for Health Research and NIH.

Kisspeptin-54 Accurately Identifies Hypothalamic Gonadotropin-Releasing Hormone Neuronal Dysfunction in Men with Congenital Hypogonadotropic Hypogonadism

BACKGROUND

Hypogonadotropic hypogonadism (HH) is hypogonadism due to either hypothalamic or pituitary dysfunction. While gonadotropin-releasing hormone (GnRH) can directly test pituitary function, no specific test of hypothalamic function exists. Kisspeptin-54 (KP54) is a neuropeptide that directly stimulates hypothalamic GnRH release and thus could be used to specifically interrogate hypothalamic function. Congenital HH (CHH) is typically due to variants in genes that control hypothalamic GnRH neuronal migration or function. Thus, we investigated whether KP54 could accurately identify hypothalamic dysfunction in men with CHH.

METHODS

Men with CHH (n = 21) and healthy eugonadal men (n = 21) received an intravenous bolus of either GnRH (100 μg) or KP54 (6.4 nmol/kg), on 2 occasions, and were monitored for 6 h after administration of each neuropeptide.

RESULTS

Maximal luteinizing hormone (LH) rise after KP54 was significantly greater in healthy men (12.5 iU/L) than in men with CHH (0.4 iU/L; p < 0.0001). KP54 more accurately differentiated CHH men from healthy men than GnRH (area under receiver operating characteristic curve KP54: 1.0, 95% CI 1.0-1.0; GnRH: 0.88, 95% CI 0.76-0.99). Indeed, all CHH men had an LH rise <2.0 iU/L following KP54, whereas all healthy men had an LH rise >4.0 iU/L. Anosmic men with CHH (i.e., Kallmann syndrome) had even lower LH rises after KP54 than did normosmic men with CHH (p = 0.017). Likewise, men identified to have pathogenic/likely pathogenic variants in CHH genes had even lower LH rises after KP54 than other men with CHH (p = 0.035).

CONCLUSION

KP54 fully discriminated men with CHH from healthy men. Thus, KP54 could be used to specifically interrogate hypothalamic GnRH neuronal function in patients with CHH.

Acute Effects of Glucagon on Reproductive Hormone Secretion in Healthy Men

CONTEXT

Glucagon increases energy expenditure; consequently, glucagon receptor agonists are in development for the treatment of obesity. Obesity negatively affects the reproductive axis, and hypogonadism itself can exacerbate weight gain. Therefore, knowledge of the effects of glucagon receptor agonism on reproductive hormones is important for developing therapeutics for obesity; but reports in the literature about the effects of glucagon receptor agonism on the reproductive axis are conflicting.

OBJECTIVE

The objective of this work is to investigate the effect of glucagon administration on reproductive hormone secretion in healthy young men.

DESIGN

A single-blinded, randomized, placebo-controlled crossover study was conducted.

SETTING

The setting of this study was the Clinical Research Facility, Imperial College Healthcare NHS Trust.

PARTICIPANTS

Eighteen healthy eugonadal men (mean ± SEM: age 25.1 ± 1.0 years; body mass index 22.5 ± 0.4 kg/m2; testosterone 21.2 ± 1.2 nmol/L) participated in this study.

INTERVENTION

An 8-hour intravenous infusion of 2 pmol/kg/min glucagon or rate-matched vehicle infusion was administered.

MAIN OUTCOME MEASURES

Luteinizing hormone (LH) pulsatility; LH, follicle-stimulating hormone (FSH), and testosterone levels were measured.

RESULTS

Although glucagon administration induced metabolic effects (insulin area under the curve: vehicle 1065 ± 292 min.µU/mL vs glucagon 2098 ± 358 min.µU/mL, P < .001), it did not affect LH pulsatility (number of LH pulses/500 min: vehicle 4.7 ± 0.4, glucagon 4.2 ± 0.4, P = .22). Additionally, there were no significant differences in circulating LH, FSH, or testosterone levels during glucagon administration compared with vehicle administration.

CONCLUSIONS

Acute administration of a metabolically active dose of glucagon does not alter reproductive hormone secretion in healthy men. These data are important for the continued development of glucagon-based treatments for obesity.

OR20-06 Kisspeptin as a Biomarker for Pregnancy Complications

Background:

Placentation (invasion of the placenta into the maternal endometrium) is hypothesised to be critical for healthy placental function and is abnormal in two thirds of miscarriage. Kisspeptin has emerged as a putative regulator of physiological placentation; it is highly expressed in placental syncitio-trophoblasts, whereas its receptor is expressed in both syncitio- and cyto-trophoblasts, such that kisspeptin is hypothesized to play an important paracrine role to regulate placentation. Circulating kisspeptin levels are considerably raised during healthy pregnancy and are reduced in women with miscarriage.

Aim:

We aimed to investigate the utility of circulating kisspeptin concentrations in the assessment of pregnancy complications and assess whether kisspeptin provides additional diagnostic information compared to beta human chorionic gonadotropin (βhCG) alone.

Methods:

This study was performed in collaboration with the Early Pregnancy Outcome Study (EPOS), which aims to identify novel pregnancy biomarkers. Women were invited to attend every fortnight for blood-sampling, clinical and ultrasound assessment during the first trimester, and repeated during the second and third trimesters. Asymptomatic women with healthy pregnancy (n=265) provided 960 blood-samples. Women with pregnancy complications including miscarriage (n=95), pre-eclampsia (PET; n=24), pregnancy induced hypertension (PIH; n=14), gestational diabetes (GDM; n=41), preterm birth (PTB; n=14) and intrauterine growth restriction (IUGR; n=24) provided 569 blood-samples.

Results:

Gestation-adjusted circulating kisspeptin and βhCG levels were lower, by 66% and 57%, respectively, in women with miscarriage compared to healthy pregnant controls (p<0.0001). Area under ROC curve for diagnosis of miscarriage was greater for the combination of both kisspeptin and βhCG together (0.92) than for either measure alone (βhCG 0.859, kisspeptin 0.874). An adjusted logistic regression model revealed that an 100pmol/L increase in plasma kisspeptin reduced the odds of miscarriage by 42%. Gestation-adjusted kisspeptin levels were lower in women with GDM (P=0.002), or IUGR (P<0.0001), and higher in women with PTB (P=0.004). Kisspeptin increased with gestation greater in PET (P=0.008) and PIH (P<0.0001) than in healthy controls.

Conclusions:

Plasma kisspeptin is a promising biomarker for pregnancy complications and provides additional diagnostic capability over that provided by βhCG alone.

Effects of Glucagon-like Peptide-1 on the Reproductive Axis in Healthy Men

CONTEXT

Glucagon-like peptide-1 (GLP-1) potently reduces food intake and augments glucose-stimulated insulin secretion. Recent animal data suggest that GLP-1 may also influence reproduction. As GLP-1 receptor agonists are currently widely used in clinical practice to treat obesity/type 2 diabetes, it is necessary to determine the effects of GLP-1 on the reproductive system in humans.

OBJECTIVE

To investigate the effects of GLP-1 administration on the reproductive axis in humans.

DESIGN

Single-blind, randomized, placebo-controlled crossover study.

SETTING

Clinical Research Facility, Imperial College Healthcare NHS Trust.

PARTICIPANTS

Eighteen healthy men (mean age 24.7 ± 0.1years, mean BMI 22.1 ± 0.4kg/m2).

INTERVENTION

Eight-hour intravenous infusion of 0.8 pmol/kg/min GLP-1 or rate-matched vehicle infusion.

MAIN OUTCOME MEASURES

Number of luteinizing hormone (LH) pulses, LH, follicle-stimulating hormone (FSH), and testosterone levels.

RESULTS

The number of LH pulses (number of LH pulses/500 min: vehicle 4.2 ± 0.4, GLP-1 4.5 ± 0.3, P = 0.46), LH area under the curve (AUC) (vehicle 1518 ± 88min.IU/L, GLP-1 1524 ± 101min.IU/L, P = 0.95), follicle-stimulating hormone AUC (vehicle 1210 ± 112 min IU/L, GLP-1 1216 ± 112 min IU/L, P = 0.86), and testosterone AUC (vehicle 10893 ± 615 min nmol/L, GLP-1 11088 ± 792 min nmol/L, P = 0.77) did not significantly differ during vehicle and GLP-1 administration. Glucagon-like peptide-1 significantly reduced food intake (vehicle 15.7 ± 1.3 kcal/kg, GLP-1 13.4 ± 1.3 kcal/kg, P = 0.01).

CONCLUSIONS

In contrast to the animal literature, our data demonstrate that acute GLP-1 administration does not affect reproductive hormone secretion in healthy men.

Effects of Peptide YY on the Hypothalamic-Pituitary-Gonadal Axis in Healthy Men

CONTEXT

Central and peripheral administration of peptide YY (PYY) has potent anorectic effects, and PYY analogs are under development as antiobesity treatments. Recent animal data suggest PYY may also influence the reproductive axis; however the effects of PYY on the human reproductive system are unknown.

OBJECTIVE

To investigate the effects of PYY administration on the reproductive axis in healthy young men.

DESIGN

Single-blind, randomized, placebo-controlled crossover study.

SETTING

Clinical Research Facility, Imperial College Healthcare NHS Trust.

PARTICIPANTS

Eighteen healthy eugonadal men (mean age 24.1 ± 0.9 years, mean body mass index 22.2 ± 0.4 kg/m2).

INTERVENTION

Eight-hour intravenous infusion of 0.4 pmol/kg/min PYY3-36 or rate-matched vehicle infusion.

MAIN OUTCOME MEASURES

Number of luteinizing hormone (LH) pulses, LH, follicle stimulating hormone (FSH), and testosterone levels.

RESULTS

The number of LH pulses (mean number of LH pulses/8 hours: PYY 4.4 ± 0.3 vs vehicle 4.4 ± 0.4, P > .99), LH area under the curve (AUC) (PYY 1503 ± 79 IU.min/L vs vehicle 1574 ± 86 IU.min/L, P = .36), FSH AUC (PYY 1158 ± 513 IU.min/L vs vehicle 1199 ± 476 IU.min/L, P = .49) and testosterone AUC (PYY 10 485 ± 684 IU.min/L vs vehicle 11 133 ± 803 IU.min/L, P = .24) were similar during PYY and vehicle infusions.

CONCLUSIONS

Acute intravenous infusion of 0.4 pmol/kg/min PYY does not affect the reproductive axis in healthy men.

OR32-3 Kisspeptin- a Novel Clinical Test of Hypothalamic Function in Men with Hypogonadotrophic Hypogonadism

Background: Hypogonadotrophic Hypogonadism is characterised by hypogonadism in the context of low / inappropriately normal gonadotrophin levels. Congenital HH (CHH) occurs due to defective hypothalamic GnRH neuronal migration (e.g. Kallman’s syndrome), or secretion. However, no direct test of hypothalamic GnRH neuronal function currently exists. Kisspeptin is a neuropeptide that stimulates endogenous hypothalamic GnRH release. Thus, we investigated whether kisspeptin could be used to interrogate hypothalamic function in men with CHH. Methods: Men with CHH (low testosterone, low LH/FSH, normal MRI pituitary / baseline pituitary function, absent puberty, unprimed by pulsatile GnRH; n=4) and healthy eugonadal men (n=20) received an intravenous bolus of GnRH (100mcg), or kisspeptin-54 (6.4nmol/kg), on two study visits ≥1 week apart. Serum gonadotrophins were measured every 15mins for 6hrs following injection. Increases in serum gonadotrophins from baseline following GnRH / kisspeptin in eugonadal men and CHH were compared by unpaired t test. Results: Mean increase in serum LH from baseline was 8.2±3.8iU/L in eugonadal men and 0.12±0.13iU/L in CHH (P=0.0003) following kisspeptin administration. All eugonadal men had an LH increase >1.5iU/L, whereas all men with CHH had an LH increase <1.5iU/L following kisspeptin. In contrast, mean increase in serum LH from baseline following GnRH was 6.2±3.2iU/L in eugonadal men and 2.2±3.8iU/L in CHH (P=0.062). Therefore, whilst the kisspeptin-induced LH increase effectively discriminated men with HH from eugonadal men (area under ROC 1.0), GnRH-induced LH increase was less discriminatory (area under ROC 0.82). In eugonadal men, the maximal increase in LH following kisspeptin significantly predicted the maximal increase in LH following GnRH (univariate linear regression, r²=0.45; P=0.0013), however this relationship was lost in men with HH (r²=0.03; P=0.83). Conclusion: Collectively, these data confirm that a novel kisspeptin test of hypothalamic GnRH function can better discriminate men with CHH from eugonadal men than currently available investigations (such as GnRH test). Therefore, a kisspeptin test could offer significant clinical benefit for the accurate diagnosis and management of patients with hypogonadism.

OR06-2 Kisspeptin Enhances Brain Processing of Olfactory and Visual Cues of Attraction in Men

BACKGROUND Successful reproduction is fundamental to all organisms, and in higher species relies on the integration of sensory cues of attraction with corresponding emotions and behaviours. However, these processes remain poorly understood. Kisspeptin is a potent activator of the reproductive axis with emerging evidence that it plays a role at the interface between reproduction and brain pathways controlling emotion and behavior. Indeed, kisspeptin receptors have also been identified in brain regions related to olfaction, sex and emotion. However, the effects of kisspeptin on human attraction have not been studied. To address this, we hypothesized that kisspeptin modulates olfactory and visual cues of attraction in healthy men. METHODS To test our hypothesis, we examined the effects of kisspeptin compared to vehicle administration on brain activity during olfactory and facial attractiveness tasks using functional MRI in 33 healthy heterosexual men (age 24.5±0.7y, BMI 22.9±0.8kg/m²). During the olfactory task, participants received a pleasant feminine scent (Chanel No.5) and during the facial attractiveness task they viewed images of unfamiliar female faces from a validated database. Participants also completed psychometric and behavioural questionnaires. RESULTS When exposed to a pleasant feminine scent, kisspeptin significantly enhanced brain activity compared to vehicle in regions related to olfaction and emotion. These included key components of the main olfactory network (p=0.008), along with other limbic structures which also express kisspeptin receptors such as the amygdala, hippocampus, thalamus, putamen, globus pallidus, and caudate (all p<0.05). When viewing female faces, kisspeptin significantly enhanced brain activity compared to vehicle in the primary aesthetic brain region; the medial prefrontal cortex (mPFC). This effect of kisspeptin on the mPFC was seen in response to faces rated high (p=0.0043), medium (p=0.0004) and low attractiveness (p=0.0085). Additionally, we observed correlations between the effects of kisspeptin on aforementioned brain activity and psychometric parameters of reward, orgasmic function and sexual desire (all p<0.01). CONCLUSIONS Collectively, we demonstrate for the first time that kisspeptin administration enhances brain responses to olfactory and visual cues of attraction in humans. Furthermore, this correlates with related psychometric parameters, thus providing key functional relevance. Our results point to a novel physiological pathway integrating attraction with reproductive hormones and behaviour in humans. These data have important implications for our understanding of human reproductive physiology, as well as the ongoing development of kisspeptin-based therapeutics to treat related reproductive disorders of body and mind.

OR33-4 A Single Subcutaneous Injection Of The Kisspeptin Analogue, MVT-602, Induces A More Prolonged LH Surge Compared With Kisspeptin-54 In Healthy Women

Background Kisspeptin is a hypothalamic neuropeptide that is requisite for normal reproductive health. A subcutaneous bolus of the native form of kisspeptin (kisspeptin-54; KP54) induces an LH-surge lasting 12-14hrs, to safely mature oocytes during in vitro fertilisation (IVF) treatment. The kisspeptin analogue, MVT-602, has a longer half-life (t_1/2 1.5-2.2h) than native KP54 (t_1/2 0.5h), which could therefore confer significant advantages as an oocyte maturation trigger in the treatment of infertility. Whilst MVT-602 has been shown to stimulate LH release in men, its effects in women have not previously been investigated. To address this, we studied the effect of MVT-602 on gonadotrophin release in healthy women for the first time. Methods A two-phase dose-finding study was undertaken during the early follicular phase (Day 1-4) of 12 healthy women aged 18-35yrs with regular menstrual cycles. During phase 1, a broad dose-range for MVT-602 was determined: three women received a single subcutaneous bolus of one of five doses of MVT-602 (0.003, 0.03, 0.1, 0.3, or 1.0nmol/kg) in successive menstrual cycles. Reproductive hormones were measured every 30min for 14hrs post-MVT-602, and again at 24hrs and 48hrs post-injection. During phase 2, an additional 9 women received either KP54 (9.6nmol/kg), or MVT-602 at doses of 0.01 or 0.03nmol/kg during the follicular phase of successive menstrual cycles, following which reproductive hormone levels were monitored every 30mins for 24hrs post-injection. Intervention groups were compared by one-way ANOVA with post hoc Tukey’s test. ResultsPhase 1: Peak serum LH levels occurred between 14-24hrs and no further increases occurred with MVT-602 at doses greater than 0.03 nmol/kg. Phase 2: Peak amplitude of serum LH was found to be similar following KP54 and MVT-602 (mean±SD of peak LH KP54 12.3 ±5.3iU/L; MVT-602 0.01nmol/kg 11.4 ±4.2iU/L; MVT-602 0.03nmol/kg 11.1 ±3.0iU/L, p>0.05). However, time to peak LH was later following MVT-602 (22hrs) when compared with KP54 (4.9hrs; P<0.0001). Thus, the area under the curve (AUC) for LH exposure was significantly increased following MVT-602 when compared with KP54 (mean±SD of AUC LH KP54 9,095 ±5,632iU.min/L; MVT-602 0.01nmol/kg 18,129 ±6,471iU.min/L, P=0.02 vs KP54; MVT-602 0.03nmol/kg 20,086 ±6,227iU.min/L, P=0.004 vs KP54). Conclusion A single subcutaneous bolus of MVT-602 in healthy women resulted in an LH surge of similar amplitude, but of longer duration than by KP54. During studies evaluating the utility of KP54 as a trigger of oocyte maturation in IVF treatment, extending the duration of LH surge with a second bolus of KP54 safely optimised oocyte maturation. Thus, the prolonged gonadotrophin surge induced by MVT-602 could be of significant utility not only to safely optimise oocyte maturation in IVF treatment, but also to treat other reproductive disorders affecting women’s health.

SUN-LB044 Effects of Glucagon-Like Peptide-1 (GLP-1) on the Hypothalamic-Pituitary-Gonadal Axis in Healthy Men

Introduction: Normal fertility requires the presence of adequate nutritional stores. The hormone glucagon-like peptide-1 (GLP-1) is a satiety hormone, which is released by intestinal L-cells during meal ingestion to act as a physiological signal of nutritional intake. GLP-1 reduces appetite and stimulates insulin release. Peripheral GLP-1 crosses the blood brain barrier and GLP-1 receptors (GLP-1R) are present in the arcuate nucleus of the hypothalamus (a neuroendocrine centre that regulates metabolism and reproduction). Both in vitro and in vivo animal studies have demonstrated stimulatory effects of GLP-1 on reproductive hormone release. Thus, GLP-1 acts as a signal of adequate energy intake and may act as a key mediator between metabolic and reproductive systems in animals. As GLP-1R agonists are widely used to treat obesity and diabetes, we sought to determine the effects of GLP-1 on the reproductive axis in humans. Methods: Using a blinded placebo-controlled protocol, 18 healthy men (age 24.7±1yr; mean BMI 22.1±0.4kg/m²) received an 8-hour infusion of 0.8pmol/kg/min of GLP-1 on one study visit and rate-matched vehicle infusion on a separate study visit, in random order. Blood samples were taken every ten minutes during infusions. Visual analogue scales (VAS: 0-10cm) for hunger and nausea were completed by the volunteers pre-, mid- and end-infusion. An ad libitum meal study was performed following the last VAS assessment, after which the infusion was stopped. Luteinizing hormone (LH) pulsatility was determined using blinded deconvolution analysis. Data is presented as mean±SEM. Results: GLP-1 infusion resulted in 14% lower food intake (GLP-1 937±87kcal vs vehicle 1094±87kcal, p=0.03) without increasing nausea (change from baseline VAS score: GLP-1 0.25±0.35cm vs vehicle 0.25±0.22cm, p=0.74). There was no difference in the number of LH pulses over 8hrs (GLP-1 4.7±0.3 vs vehicle 4.4±0.4, p=0.38), LH pulse mass (GLP-1 4.82±0.38IU/L vs vehicle 4.78±0.42IU/L, p=0.94), mean LH (GLP-1 2.86±0.2IU/L vs vehicle 2.75±0.2IU/L, p=0.50), LH AUC (GLP-1 1524±101IU.min/L vs vehicle 1484±88IU.min/L, p=0.70), FSH AUC (GLP-1 1216±112IU.min/L vs vehicle 1210±112IU.min/L, p=0.86) or testosterone AUC (GLP-1 11088±792nmol.min/L vs vehicle 10893±615nmol.min/L, p=0.77). Conclusions: Our results indicate that GLP-1 administration, at a biologically active dose (which reduces food intake), has neither a detrimental nor stimulatory effect on the reproductive axis. This provides important safety data for GLP-1 based therapeutic agents. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Establishing a model for childhood obesity in adolescent pigs

OBJECTIVE

Rising worldwide prevalence of obesity and metabolic diseases in children has accentuated the importance of developing prevention and management strategies. The objective of this study was to establish a model for childhood obesity using high-fat feeding of adolescent pigs, as pigs have a longer developmental period and are physiologically more similar to humans than rodents.

METHODS

Crossbred pigs were fed a high-fat diet (HFD) or low-fat diet (n = 6/treatment) from postnatal day 49 to 84. On postnatal day 84, an oral glucose tolerance test was performed, jugular blood sampled to determine lipopolysaccharide levels and plasma lipids, intestinal digesta collected to characterize microbial and metabolite composition and back fat and intestinal tissue assayed for gene expression.

RESULTS

Five-week HFD increased weight gain and back fat thickness, caused dyslipidaemia and impaired glucose tolerance and increased expression of genes in back fat suggesting inflammation. HFD pigs had distinct proximal colon microbiota with 48% reduction (P < 0.05) in Bacteroidetes and increased expression of pro-inflammatory genes interleukin-18 and tumour necrosis factor in ileum (P < 0.05).

CONCLUSIONS

These findings indicate that adolescent pigs should be considered a suitable model for childhood obesity, because short-term HFD feeding is sufficient to induce obesity and glucose intolerance, recapitulating disease characteristics in adolescent pigs.

An Unusual Case of Acute Muscle Weakness

A previously healthy 35-year old man presented to hospital with acute leg weakness following an alcohol binge. On assessment, tachycardia, urinary retention and bilateral upper and lower limb proximal weakness with preserved peripheral power were noted. Biochemistry revealed marked hypokalaemia, which responded to intravenous replacement, and biochemical thyrotoxicosis, leading to the diagnosis of Thyrotoxic Periodic Paralysis (TPP). Anti-thyroid therapy and beta-blockers were commenced and his neurological symptomatology resolved as he became progressively euthyroid. TPP is a rare acquired subtype of hypokalaemic periodic paralysis, typically causing proximal muscle weakness associated with thyrotoxicosis. It is most common in young Asian males. Acute treatment requires cautious oral potassium supplementation, beta-blockade, and anti-thyroid therapy. TPP is prevented by maintaining euthyroidism; otherwise recurrence is likely.

Safety and Immunogenicity of a Pentavalent Combination Vaccine (Diphtheria, Tetanus, Acellular Pertussis, Polio and Haemophilus Influenzae Type b Conjugate) When Administered as a Fourth Dose at 15 to 18 Months of Age

A DTaP-IPV//PRP-T combination vaccine (Pentacel) has been universally used in Canada to provide immunization against diphtheria, tetanus, pertussis, polio, and Haemophilus influenzae type b with single injections at 2, 4, 6 and 18 months of age. This randomized, multicenter study was conducted to evaluate administration of a fourth dose of DTaP-IPV//PRP-T at 15 to 18 months of age, similar to the US immunization schedule. Participants who had received three doses of DTaP-IPV//PRP-T by 8 months of age were enrolled at 12 months and randomized to receive a fourth dose at 15, 16, 17 or 18 months. Antibody levels for each vaccine antigen were measured prior to and four weeks following booster vaccination. Overall, 1782 subjects were immunized and monitored for adverse events, and 735 were evaluated for immune responses. Preimmunization antibody levels differed minimally by age, for all antigens. The immune responses elicited by DTaP-IPV//PRP-T were comparable between participants vaccinated at 15 or 16 months and those vaccinated at 17 or 18 months, as demonstrated by specific antibody geometric mean titers, seroprotection/seroresponse rates, and reverse cumulative distribution curves. The fourth dose was well tolerated in all age groups. Toddlers at 15, 16, 17 or 18 months of age are equally suitable recipients for booster immunization with the DTaP-IPV//PRP-T vaccine.

Transanal dearterialization with targeted mucopexy is effective for advanced haemorrhoids

AIM

Transanal haemorrhoidal dearterialization (THD) has become well established for the treatment of haemorrhoids. In this study we describe a technical modification of this technique, targeted mucopexy (THD TM), and report the results for advanced haemorrhoids.

METHOD

The study included a prospective evaluation of patients with Grade IV (fourth-degree) haemorrhoids operated on with the THD TM technique. This consisted of an initial dearterialization when the haemorrhoidal arteries were transfixed and a second phase of mucopexy, using a different needle from that usually used in the original technique.

RESULTS

From January 2007 to December 2011, 31 consecutive patients with Grade IV haemorrhoids were operated on using the THD TM technique. Postoperative pain was reported by 22 (70%) patients on day 1 and 19 (61%) on day 7, while nine (30%) did not experience any pain at all. Severe pain was reported by only nine (16%) patients. At a mean follow-up of 32 months, two (6.4%) patients required a further intervention for on-going symptoms.

CONCLUSION

Transanal haemorrhoidal dearterialization TM is effective for advanced haemorrhoids.

Palliative care clinical trials: how nurses are contributing to integrated, evidence-based care

The aim of this paper is to describe the emerging role of the palliative care clinical trials nurse in an era of evidence-based practice and increasing clinical trial activity in palliative care settings across Australia. An overview of the current clinical trials work is provided, with a focus on three aspects of clinical trials nursing practice that have significant implications for patients: managing the consent process, integrating clinical trials into multidisciplinary care, and establishing and building the evidence base to inform practice in palliative care settings. Clinical trials roles provide palliative care nurses with an opportunity to contribute to clinical research, help expand palliative care's evidence base, and develop their own research capabilities.

Characterization of particulate matter size distributions and indoor concentrations from kerosene and diesel lamps

Over one-quarter of the world's population relies on fuel-based lighting. Kerosene lamps are often located in close proximity to users, potentially increasing the risk for respiratory illnesses and lung cancer. Particulate matter concentrations resulting from cook stoves have been extensively studied in the literature. However, characterization of particulate concentrations from fuel-based lighting has received minimal attention. This research demonstrates that vendors who use a single simple wick lamp in high-air-exchange market kiosks will likely be exposed to PM(2.5) concentrations that are an order of magnitude greater than ambient health guidelines. Using a hurricane lamp will reduce exposure to PM(2.5) and PM(10) concentrations by an order of magnitude compared to using a simple wick lamp. Vendors using a single hurricane or pressure lamp may not exceed health standards or guidelines for PM(2.5) and PM(10), but will be exposed to elevated 0.02-0.3 μm particle concentrations. Vendors who change from fuel-based lighting to electric lighting technology for enhanced illumination will likely gain the ancillary health benefit of reduced particulate matter exposure. Vendors exposed only to ambient and fuel-based lighting particulate matter would see over an 80% reduction in inhaled PM(2.5) mass if they switched from a simple wick lamp to an electric lighting technology.

PRACTICAL IMPLICATIONS

Changing lighting technologies to achieve increased efficiency and energy service levels can provide ancillary health benefits. The cheapest, crudest kerosene lamps emit the largest amounts of PM(2.5). Improving affordability and access to better lighting options (hurricane or pressure lamps and lighting using grid or off-grid electricity) can deliver health benefits for a large fraction of the world's population, while reducing the economic and environmental burden of the current fuel-based lighting technologies.

Activity of aortic chemoreceptors during electrical stimulation of the stellate ganglion in the cat

1. In anaesthetized cats, action potentials from aortic chemoreceptors were recorded during electrical stimulation of preganglionic sympathetic fibres to the decentralized right stellate ganglion. The rate of discharge in afferents in the ipsilateral but not in the contralateral aortic nerve increased when stimulus frequency was 4/sec or higher.2. The post-ganglionic fibres in the stimulated pathway originate in the right stellate ganglion. They leave the ganglion in the caudal limb of the ansa subclavia, and the results suggest that the ipsilateral aortic nerve and its branches distribute sympathetic fibres as well as afferents to aortic bodies.3. In contrast, the rate of discharge of chemoreceptor fibres in the contralateral aortic nerve fell as blood pressure increased during sympathetic stimulation. Sympathetic pathways to the aortic bodies can maintain or increase chemoreceptor discharge during hypertension elicited by sympathetic activation.

Evaluation of AZD8931, an Equipotent Inhibitor of erbB1, erbB2, and erbB3 Receptor Signaling, on Ligand Stimulated Breast Cancer Cell Lines with Differing Levels of erbB2 Expression

Background: Further treatment options for patients whose breast cancers do not overexpress erbB2 are required. AZD8931, an equipotent, reversible inhibitor of erbB1 (HER1, EGFR), erbB2 (HER2), and erbB3 (HER3) receptor signaling may be useful in this setting and may lead to inhibition of tumor cell proliferation, invasion, metastasis, angiogenesis and tumor cell survival.Objectives: To compare the activity of AZD8931 with other erbB inhibitors (gefitinib [G] and lapatinib [L]) in breast cancer cell lines stimulated with erbB ligands.Methods: A panel of 9 breast cancer cell lines with differing erbB2 expression levels were used: erbB2+/ER+ (BT474c; MDA-MB-361); erbB2+/ER- (MDA-MB-453; SKBR-3); erbB2-/ER+ (MCF7; T47D; ZR75-1); or erbB2-/ER- (MDA-MB-231; MDA-MB-468). Following overnight serum starvation, cells were incubated with AZD8931, G or L (0-10 µM) for 90 min and then stimulated with erbB ligands (50 ng/ml; EGF, TGFα, amphiregulin, epiregulin, betacellulin, neuregulin1, or HBEGF) for 5 min before lysis. Levels of phosphorylated erbB1, erbB2, and erbB3 were analyzed by ELISA. For IC50 determination, mean basal phosphorylation was subtracted. Geometric mean IC50s were calculated from triplicate assays and 2-sided unequal variance t-tests compared logIC50s.Results: AZD8931 demonstrated potent inhibitory activity (IC50s ≤10610 nM) when phosphorylation of erbB1, erbB2 or erbB3 receptors was driven by any erbB ligand. G demonstrated potent inhibitory activity (IC50s ≤20 nM) when the phosphorylation of erbB1 and erbB2 was driven by any erbB ligand. L more strongly inhibited the phosphorylation of erbB2 (IC50s ≤10 nM) than erbB1 (IC50s &lt;400 nM) and showed a ligand and cell-dependant range of activities against erbB3 phosphorylation. AZD8931 was particularly differentiated from G and L in the inhibition of neuregulin1-driven erbB3 phosphorylation: IC50s were lower for AZD8931 (1-5 nM) than for G (1-120 nM) or L (20-80 nM) in the majority of the cell lines tested. Inhibition of erbB1 phosphorylation driven by EGF (IC50s ≤ vs &gt;20 nM), TGFα (≤5 vs &gt;20 nM), HB-EGF (≤ vs &gt;25 nM), or betacellulin (≤6 vs 10-118 nM) also indicated more potent inhibitory activity for AZD8931 over L in cell lines that respond to ligand stimulation. No phosphorylation response to amphiregulin was seen in any of the cell lines.Conclusion: This study demonstrates that in a range of breast cell lines with varying levels of erbB2 expression, AZD8931 is a potent and balanced inhibitor of erbB1, erbB2, and erbB3 signaling. The pharmacological profile of AZD8931 is thus distinct from G and L and suggests that AZD8931 offers an agent to test the hypothesis that combined, balanced inhibition of erbB signaling could provide clinical benefit. AZD8931 may be particularly useful in the treatment of solid tumors that do not overexpress erbB2 including trastuzumab-ineligible breast cancer, an area of unmet medical need. AZD8931 is being evaluated in a Phase I clinical trial.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5059.

Male circumcision for the prevention of heterosexually acquired HIV infection: a meta-analysis of randomized trials involving 11,050 men

OBJECTIVES

Observational studies and a small collection of randomized controlled trials (RCTs) suggest that male circumcision may significantly reduce HIV transmission between sero-discordant contacts. The Joint United Nations Programme on HIV/AIDS (UNAIDS) and World Health Organization have recently announced recommendations to scale up male circumcision in countries with generalized epidemics and low levels of male circumcision. However, no meta-analysis has been conducted to determine the effectiveness of this intervention.

METHODS

We conducted a systematic review of medical literature, and included any RCTs assessing male circumcision to prevent heterosexually acquired HIV infection among males. We used the DerSimonian-Laird random effects method to pool study outcomes. We calculated the relative risk (RR), risk difference, number needed to treat (NNT) and I(2), all with 95% confidence intervals (CIs).

RESULTS

We identified three RCTs that met our inclusion criteria, involving a total of 11 050 men. The pooled RR was 0.44 (95% CI 0.33-0.60, P<0.0001, I(2)=0%, 95% CI 0-35%). The risk difference was 0.014 (95% CI 0.07-0.21), yielding a NNT of 72 (95% CI 50-143).

CONCLUSIONS

Male circumcision is an effective strategy for reducing new male HIV infections. Its impact on a population level will require consistently safe sexual practices to maintain the protective benefit.

Efficacy of influenza vaccination in HIV-positive patients: a systematic review and meta-analysis

BACKGROUND

International treatment guidelines recommend that HIV-positive patients be vaccinated for influenza annually. Evidence supporting this recommendation is limited. We assessed the efficacy of influenza vaccines in preventing influenza in HIV-positive patients through a systematic review and meta-analysis.

METHODS

We searched 10 electronic databases independently, in duplicate (from inception to June 2007). We extracted data on study design, population characteristics and outcomes related to influenza symptoms and antibody titres. We pooled data using a random effects model and conducted sensitivity analyses to evaluate heterogeneity.

RESULTS

We included four studies. Three studies were evaluable for meta-analysis and yielded a pooled relative risk reduction (RRR) of 66% [95% confidence interval (CI) 36-82%; I(2)=73%]. One case-control study yielded an odds ratio of 1.98 (95% CI 0.75-5.20). When we assessed heterogeneity according to study design, we found that the study of the highest quality, a randomized clinical trial (RCT), yielded the most conservative estimate (RRR 41%; 95% CI 2-64%).

INTERPRETATION

Evidence supporting influenza vaccination of HIV-positive individuals is limited, poorly quantified and characterized by substantial methodological shortcomings. A reasonable estimate of influenza vaccination effectiveness in HIV-positive patients cannot be derived from these data. There is an urgent need for randomized trials to guide policy and clinical practice.