Giving weight to incretin-based pharmacotherapy for obesity-related sleep apnea: a revolution or a pipe dream?

Obesity is a chronic disease affecting over 670 million adults globally, with multiple complications including obstructive sleep apnea (OSA). Substantial weight loss in patients with obesity-related OSA can reduce or even eliminate OSA as well as reduce sleepiness and improve cardio-metabolic health. Evidence suggests that these improvements exceed those that occur with device-based OSA therapies like continuous positive airway pressure which continue to be the first-line of therapy. Resistance to weight management as a first-line strategy to combat OSA could arise from the complexities in delivering and maintaining adequate weight management, particularly in sleep clinic settings. Recently, incretin-based pharmacotherapies including glucagon-like peptide 1 (GLP-1) receptor agonists alone or combined with glucose-dependent insulinotropic polypeptide (GIP) receptor agonists have been developed to target glycemic control in type 2 diabetes. These medications also slow gastric emptying and reduce energy intake. In randomized, placebo-controlled trials of these medications in diabetic and non-diabetic populations with obesity, participants on active medication lost up to 20% of their body weight, with corresponding improvements in blood pressure, lipid levels, physical functioning, and fat mass loss. Their adverse effects are predominantly gastrointestinal-related, mild, and transient. There are trials currently underway within individuals with obesity-related OSA, with a focus on reduction in weight, OSA severity, and cardio-metabolic outcomes. These medications have the potential to substantially disrupt the management of OSA. Pending coming data, we will need to consider pharmacological weight loss as a first-line therapy and how that influences training and management guidelines.

Safety of higher doses of melatonin in adults: A systematic review and meta-analysis

Melatonin is commonly used for sleep and jetlag at low doses. However, there is less documentation on the safety of higher doses, which are being increasingly used for a wide variety of conditions, including more recently COVID-19 prevention and treatment. The aim of this review was to investigate the safety of higher doses of melatonin in adults. Medline, Scopus, Embase and PsycINFO databases from inception until December 2019 with convenience searches until October 2020. Randomised controlled trials investigating high-dose melatonin (≥10 mg) in human adults over 30 years of age were included. Two investigators independently abstracted articles using PRISMA guidelines. Risk of bias was assessed by a committee of three investigators. 79 studies were identified with a total of 3861 participants. Studies included a large range of medical conditions. The meta-analysis was pooled data using a random effects model. The outcomes examined were the number of adverse events (AEs), serious adverse events (SAEs) and withdrawals due to AEs. A total of 29 studies (37%) made no mention of the presence or absence of AEs. Overall, only four studies met the pre-specified low risk of bias criteria for meta-analysis. In that small subset, melatonin did not cause a detectable increase in SAEs (Rate Ratio = 0.88 [0.52, 1.50], p = .64) or withdrawals due to AEs (0.93 [0.24, 3.56], p = .92), but did appear to increase the risk of AEs such as drowsiness, headache and dizziness (1.40 [1.15, 1.69], p < .001). Overall, there has been limited AE reporting from high-dose melatonin studies. Based on this limited evidence, melatonin appears to have a good safety profile. Better safety reporting in future long-term trials is needed to confirm this as our confidence limits were very wide due to the paucity of suitable data.

Development and validation of a model for diagnosis of obstructive sleep apnoea in primary care

BACKGROUND AND OBJECTIVE

Use of in-laboratory polysomnography (PSG) to diagnose obstructive sleep apnoea (OSA) is cost and resource intensive. Questionnaires, physical measurements and home monitors have been studied as potential simpler alternatives. This study aimed to develop a diagnostic model for OSA for use in primary care.

METHODS

Primary care practitioners were trained to recognize symptoms of sleep apnoea and recruited patients based on the clinical need to investigate OSA. Assessment was by symptom questionnaires, anthropomorphic measurements, digital facial photography, and a single-channel nasal flow monitor (Flow Wizard©, DiagnoseIT, Sydney, Australia) worn at home for 3 nights. The in-laboratory PSG was the reference test, with OSA defined as apnoea-hypopnoea index (AHI) ≥10 events/h.

RESULTS

In the model development phase, 25 primary care practitioners studied 315 patients in whom they suspected OSA, of which 57% had AHI≥10 and 22% had AHI≥30. Published OSA questionnaires provided low to moderate prediction of OSA (area under the curve [AUC] 0.53-0.73). The nasal flow monitor alone yielded high accuracy for predicting OSA with AUC of 0.87. Sensitivity was 0.87 and specificity 0.77 at a threshold respiratory event index (REI) of 18 events/h. A model adding age, gender, symptoms and BMI to the nasal flow monitor REI only modestly improved OSA prediction (AUC 0.89), with similar AUC (0.88) confirmed in the validation population of 114 patients.

CONCLUSION

Sleep apnoea can be diagnosed in the primary care setting with a combination of clinical judgement and portable monitor test outcomes.

Does craniofacial morphology relate to sleep apnea severity reduction following weight loss intervention? A patient-level meta-analysis

STUDY OBJECTIVES

Obesity is a common and reversible risk factor for obstructive sleep apnea (OSA). However, there is substantial unexplained variability in the amount of OSA improvement for any given amount of weight loss. Facial photography is a simple, inexpensive, and radiation-free method for craniofacial assessment. Our aims were (1) to determine whether facial measurements can explain OSA changes, beyond weight loss magnitude and (2) whether facial morphology relates to how effective weight loss will be for OSA improvement.

METHODS

We combined data from three weight loss intervention trials in which participants had standardized pre-intervention facial photography (N = 91; 70.3% male, mean ± SD weight loss 10.4 ± 9.6% with 20.5 ± 51.2% apnea-hypopnea index [AHI] reduction). Three skeletal-type craniofacial measurements (mandibular length, lower face height, and maxilla-mandible relationship angle) were assessed for relationship to AHI change following weight loss intervention.

RESULTS

Weight and AHI changes were moderately correlated (rho = 0.3, p = 0.002). In linear regression, an increased maxilla-mandible relationship angle related to AHI improvement (β [95% CI] -1.7 [-2.9, -0.5], p = 0.004). Maxilla-mandible relationship angle explained 10% in the variance in AHI over the amount predicted by weight loss amount (20%). The relationship between weight change and AHI was unaffected by the maxilla-mandible relationship angle (interaction term p > 0.05).

CONCLUSIONS

Regardless of facial morphology, weight loss is similarly moderately predictive of OSA improvement. Increased maxilla-mandible relationship angle, suggestive of retrognathia, was weakly predictive of OSA response to weight loss. Although this is unlikely to be clinically useful, exploration in other ethnic groups may be warranted.

Feasibility of 3-month melatonin supplementation for brain oxidative stress and sleep in mild cognitive impairment: protocol for a randomised, placebo-controlled study

INTRODUCTION

Melatonin has multiple proposed therapeutic benefits including antioxidant properties, synchronisation of the circadian system and lowering of blood pressure. In this protocol, we outline a randomised controlled trial to assess the feasibility, acceptability and tolerability of higher dose (25 mg) melatonin to target brain oxidative stress and sleep disturbance in older adults with mild cognitive impairment (MCI).

METHODS AND ANALYSIS

The study design is a randomised double-blind, placebo-controlled, parallel group trial. Forty individuals with MCI will be recruited from the Healthy Brain Ageing Clinic, University of Sydney and from the community, and randomised to receive either 25 mg oral melatonin or placebo nightly for 12 weeks. The primary outcomes are feasibility of recruitment, acceptability of intervention and adherence to trial medication at 12 weeks. Secondary outcomes will include the effect of melatonin on brain oxidative stress as measured by magnetic resonance spectroscopy, blood pressure, blood biomarkers, mood, cognition and sleep. Outcomes will be collected at 6 and 12 weeks. The results of this feasibility trial will inform a future conclusive randomised controlled trial to specifically test the efficacy of melatonin on modifiable risk factors of dementia, as well as cognition and brain function. This will be the first trial to investigate the effect of melatonin in the population with MCI in this way, with the future aim of using this approach to reduce progression to dementia.

ETHICS AND DISSEMINATION

This protocol has been approved by the Sydney Local Health District Ethics Committee (X18-0077). This randomised controlled trial will be conducted in compliance with the protocol published in the registry, the International Conference for Harmonisation on Good Clinical Practice and all other applicable regulatory requirements. The findings of the trial will be disseminated via conferences, publications and media, as applicable. Participants will be informed of results of the study at the conclusion of the trial. Eligible authors will include investigators who are involved in the conception and design of the study, the conduct of the trial, the analysis of the results, and reporting and presentation of study findings.

TRIAL REGISTRATION NUMBER

Australian and New Zealand Clinical Trials Registry (ANZCTRN 12619000876190).

PROTOCOL VERSION

V.8 15 October 2020.

0672 The Effect Of Armodafinil On Sleep Spindles In Obstructive Sleep Apnea: Secondary Analysis Of A Randomized Placebo-controlled Trial

Introduction

Armodafinil has been trialed in OSA patients to promote wakefulness and simulated driving performance. We have previously completed a 6-month trial of 150mg of armodafinil vs placebo in moderate-severe OSA patients not using CPAP (ACTRN# 12611000847910) observing that participants on armodafinil learned to perform better across a 90-minute driving simulator task faster than those on placebo. It is possible that this reduction in time-on-task decrement may have been due to increased learning on armodafinil.

Sleep spindles have previously been implicated in procedural learning and neurobehavioral performance. We hypothesized that armodafinil increases sleep spindle events during NREM sleep to enhance learning.

Methods

Sixty-three overweight severe OSA patients (mean BMI: 32.3kg/m2 (26.1-42.5); age 53.1 years (28-71), 52 males) underwent overnight in-lab polysomnography at baseline (0 months) and at a 6-month follow-up. All-night EEG signals were analyzed using a previously validated automated spindle detection algorithm. EEG recordings were visually inspected by an experienced sleep physician (LE), who was blinded to drug allocation. To minimize the likelihood of type 1 error we selected three key spindle variables detected at Cz for analysis of change between 0 and 6 months: 1) total number of spindle events (11-16 Hz) in NREM sleep 2) density of slow spindles (≥11 to ≤ 13Hz) per minute of NREM sleep, and 3) fast spindle density in NREM (&gt;13 to ≤ 16Hz).

Results

The change in total spindle count in NREM sleep (armodafinil=11.6 vs Placebo =-17.1, p=0.57), fast spindle density (armodafinil=0.06 vs Placebo =-0.02, p=0.63) and slow spindle density (armodafinil=-0.00 vs. Placebo =-0.03, p=0.74) were not increased by armodafinil.

Conclusion

If armodafinil enhances simulated driving performance in a way that suppresses time-on-task effects it does not appear to be through a sleep spindle enhancing mechanism. Armodafinil is probably not a pharmacological method of enhancing sleep spindles.

Support

World Sleep Society (International Sleep Research Training Program)CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, University of Sydney

Objective measurement of sleep in mild cognitive impairment: A systematic review and meta-analysis

Older adults with mild cognitive impairment (MCI) are at-risk of developing dementia, particularly Alzheimer's disease. While some research suggests that alterations in sleep architecture may mediate cognitive decline, the nature and magnitude of changes to sleep macro- (sleep stages) and micro-architecture (electroencephalography (EEG) oscillations) in MCI is not yet clear. This study aimed to systematically review and meta-analyse case-control studies objectively measuring sleep in MCI. A systematic search was conducted using PubMed, Scopus, Web of Science, Embase and Psycinfo databases and after review, a total of 10 studies met inclusion criteria. Of these, all reported sleep macro-architecture and four reported micro-architecture outcomes. A combined total of 430 participants (209 with and 221 without MCI) underwent objective sleep assessments in the included full text articles. Findings show that compared to healthy controls, those with MCI have pronounced changes in sleep macro-architecture with greater wake after sleep onset, reduced total sleep time, lower sleep efficiency, longer sleep onset latency, longer rapid eye movement sleep (REM) latency, reduced REM sleep, greater N1 sleep, and worse severity of hypoxemia. Pooling of sleep micro-architecture EEG measures was not possible due to limited studies, however reduced spindles in non-REM sleep and greater EEG slowing in REM sleep were reported.

Magnesium supplementation for the treatment of restless legs syndrome and periodic limb movement disorder: A systematic review

Magnesium supplementation is often suggested for restless legs syndrome (RLS) or period limb movement disorder (PLMD) based on anecdotal evidence that it relieves symptoms and because it is also commonly recommended for leg cramps. We aimed to review all articles reporting the effects of magnesium supplementation on changes in RLS and/or PLMD. We conducted a systematic search looking for all relevant articles and then two reviewers read all article titles and abstracts to identify relevant studies. Eligible studies were scored for their quality as interventional trials. We found 855 abstracts and 16 of these could not be definitively excluded for not addressing all aspects of our research question. Seven full-text articles were unlocatable and one was ineligible which left eight studies with relevant data. One was a randomised placebo-controlled trial, three were case series and four were case studies. The RCT did not find a significant treatment effect of magnesium but may have been underpowered. After quality appraisal and synthesis of the evidence we were unable to make a conclusion as to the effectiveness of magnesium for RLS/PLMD. It is not clear whether magnesium helps relieve RLS or PLMD or in which patient groups any benefit might be seen.

A review of psychosocial factors and personality in the treatment of obstructive sleep apnoea

Effective treatment of obstructive sleep apnoea (OSA) is primarily determined by adherence to the selected intervention. The most common treatment pathways are mechanical devices such as continuous positive airway pressure (CPAP) or a mandibular advancement device, often combined with weight loss therapy. Weight reduction is usually an adjunct therapy but may be used as a secondary treatment in mild-to-moderate OSA when mechanical treatments cannot be tolerated. To enhance the uptake and adherence to treatment, clinicians may assess patient's personality profiles and psychological readiness. There is a paucity of evidence related to these aspects of patient care and this article outlines the current research in relation to patient presentation, treatment uptake and barriers, and methods to enhance treatment adherence.

This article disseminates personality traits observed in patients with OSA and identifies vulnerable groups who may require additional support to increase treatment adherence. It summarises the current evidence for treatment barriers in patients with OSA. Low self-efficacy in relation to CPAP and weight loss adherence will be explored as well as the potential to predict treatment responders and enhance therapeutic uptake and adherence. Extending personality traits into research and clinical practice could potentially result in more successful CPAP therapy and weight loss treatment outcomes.

Intra-individual stability of NREM sleep quantitative EEG measures in obstructive sleep apnea

Electroencephalography is collected routinely during clinical polysomnography, but is often utilised to simply determine sleep time to calculate apnea-hypopnea indices. Quantitative analysis of these data (quantitative electroencephalogram) may provide trait-like information to predict patient vulnerability to sleepiness. Measurements of trait-like characteristics need to have high test-retest reliability. We aimed to investigate the intra-individual stability of slow-wave (delta power) and spindle frequency (sigma power) activity during non-rapid eye movement sleep in patients with obstructive sleep apnea. We recorded sleep electroencephalograms during two overnight polysomnographic recordings in 61 patients with obstructive sleep apnea (median days between studies 47, inter-quartile range 53). Electroencephalograms recorded at C3-M2 derivation were quantitatively analysed using power spectral analysis following artefact removal. Relative delta (0.5-4.5 Hz) and sigma (12-15 Hz) power during non-rapid eye movement sleep were calculated. Intra-class correlation coefficients and Bland-Altman plots were used to assess agreement between nights. Intra-class correlation coefficients demonstrated good-to-excellent agreement in the delta and sigma frequencies between nights (intra-class correlation coefficients: 0.84, 0.89, respectively). Bland-Altman analysis of delta power showed a mean difference close to zero (-0.4, 95% limits of agreement -9.4, 8.7) and no heteroscedasticity with increasing power. Sigma power demonstrated heteroscedasticity, with reduced stability as sigma power increased. The mean difference of sigma power between nights was close to zero (0.1, 95% limits -1.6, 1.8). We have demonstrated the stability of slow-wave and spindle frequency electroencephalograms during non-rapid eye movement sleep within patients with obstructive sleep apnea. The electroencephalogram profile during non-rapid eye movement sleep may be a useful biomarker for predicting vulnerability to daytime impairment in obstructive sleep apnea and responsiveness to treatment.

Agreement between electronic and paper Epworth Sleepiness Scale responses in obstructive sleep apnoea: secondary analysis of a randomised controlled trial undertaken in a specialised tertiary care clinic

OBJECTIVES

Originally developed as a paper questionnaire, the electronic Epworth Sleepiness Scale (ESS) is widely used in sleep clinics and sleep population research. Despite potential differences between computer-based and conventional questionnaire delivery, studies have not evaluated the agreement between electronic and paper versions of the ESS. Given the widespread use of the ESS, a bias between results would present considerable data concerns. Thus, the aim of this study was to examine agreement between electronic and paper ESS responses in obstructive sleep apnoea (OSA).

DESIGN

We undertook a secondary analysis of baseline data from a randomised controlled trial (ANZCTR: ACTRN12611000847910).

SETTING

Data were collected in a tertiary sleep research laboratory located in Sydney, Australia.

PARTICIPANTS

Data were analysed from 112 adult patients with OSA.

MEASUREMENTS

Patients were given the English version of the ESS as part of a battery of sleep laboratory questionnaires. They completed electronic and subsequently paper ESS questionnaires on the same day.

RESULTS

We found no significant difference between electronic and paper ESS questionnaires (mean=0.1, SD=2.1, 95% CI -0.3 to 0.5, P=0.57) or heteroscedasticity. There was no evidence of bias along the range of the measure. 95% limits of agreement at 4.3 and -4.1 were comparable with previous data.

CONCLUSIONS

We found no evidence of bias between electronic and paper ESS questionnaires in this sample of patients with OSA, as the two formats displayed sufficient agreement to be clinically comparable. Regardless of severity, patients reported the same level of daytime sleepiness with the same level of accuracy across both measures.

TRIAL REGISTRATION NUMBER

ACTRN12611000847910; Pre-results.

Is Metabolic Rate Increased in Insomnia Disorder? A Systematic Review

Background: Insomnia disorder is a highly prevalent health condition, affecting ~10-15% of the adult population worldwide. A central feature of insomnia is hyperarousal characterized as persistent and increased somatic, cognitive and cortical stimulation. Hyperarousal leads to a state of conditioned arousal that disrupts both sleep and daytime function. Research studies have shown increases in body temperature, heart rate, electroencephalographic activity, catecholamines, and oxygen consumption as a measure of metabolic rate. These findings provide evidence of increased physiological activation in insomnia however results are not consistent. The aim of the systematic review was to determine if metabolic rate in patients with insomnia is increased in keeping with the hyperarousal hypothesis. Methods: We searched Pubmed, Web of Science, CINAHL, PsycINFO, EMBASE, and Scopus databases for observational and interventional studies that have measured metabolic rate in insomnia. Study characteristics were extracted and summarized and a risk of bias was performed for each of the studies. Results: Two reviewers screened 963 abstracts with 35 articles of interest for full-text review. Four articles evaluating 75 participants were included in this systematic review. Two studies showed increased oxygen consumption across 24 h in insomnia patients compared with good-sleeping controls. One study which measured oxygen consumption at only a single timepoint showed no difference between insomnia patients and good-sleeping controls. A further study evaluating the effect of lorazepam on oxygen consumption in patients with chronic insomnia showed that lorazepam reduced metabolic rate during the night time only. Conclusions: These findings show that metabolic rate appears to be increased across 24 h in line with the hyperarousal model of insomnia. However, these increases in metabolic rate in insomnia were minor compared to good-sleeping controls and the clinical significance is unclear. Larger, methodologically robust studies are required to confirm these findings and the effect of any increase in metabolic rate on sleep-wake disturbances or pathophysiology.

Modafinil/armodafinil in obstructive sleep apnoea: a systematic review and meta-analysis

Modafinil is used internationally to treat residual sleepiness despite continuous positive airway pressure in obstructive sleep apnoea (res-OSA). In 2011, the European Medicines Agency removed the indication based on an unfavourable risk–benefit profile in two trials for efficacy and all accumulated safety data. We performed a meta-analysis of all randomised controlled trials of modafinil (or armodafinil) in res-OSA to quantify efficacy and safety.

We systematically searched and assessed studies from major databases, conferences and trials registries to find randomised, placebo-controlled trials of modafinil/armodafinil for ≥2 weeks in adult res-OSA treating sleepiness.

We analysed 10 of the 232 articles identified that met inclusion criteria (1466 patients). Modafinil/armodafinil improved the Epworth Sleepiness Scale score (2.2 points, 95% CI 1.5–2.9) and the Maintenance of Wakefulness Test over placebo (3 min, 95% CI 2.1–3.8 min). Modafinil/armodafinil tripled adverse events and doubled adverse events leading to withdrawal but did not increase serious adverse events (hospitalisations or death).

Modafinil and armodafinil improve subjective and objective daytime sleepiness in res-OSA. We believe our analysis is a fairer analysis of the risk–benefit profile of this indication. Clinicians may want to use this data to balance the risks and benefits on a case-by-case basis with their patients.

Climate change and the evolution of high-latitude terrestrial vegetation and floras

Our understanding of polar vegetation and climate through time has expanded enormously in the past five years as a consequence of improved logistics, detailed studies of plant fossils in their proper sedimentological context, and the development of sophisticated physiognomic methods for extracting the climate signal present in plant fossil assemblages. These revelations are particularly timely in that climate change is most strongly expressed at the poles, and polar conditions play a critical role in determining global climate. By studying the evolution and change in polar vegetation, valuable insights on possible future biotic responses to global warming can be obtained.

Animal models of orthopoxvirus infection

Smallpox was one of the most devastating diseases known to humanity. Although smallpox was eradicated through a historically successful vaccination campaign, there is concern in the global community that either Variola virus (VARV), the causative agent of smallpox, or another species of Orthopoxvirus could be used as agents of bioterrorism. Therefore, development of countermeasures to Orthopoxvirus infection is a crucial focus in biodefense research, and these efforts rely on the use of various animal models. Smallpox typically presented as a generalized pustular rash with 30 to 40% mortality, and although smallpox-like syndromes can be induced in cynomolgus macaques with VARV, research with this virus is highly restricted; therefore, animal models with other orthopoxviruses have been investigated. Monkeypox virus causes a generalized vesiculopustular rash in rhesus and cynomolgus macaques and induces fatal systemic disease in several rodent species. Ectromelia virus has been extensively studied in mice as a model of orthopoxviral infection in its natural host. Intranasal inoculation of mice with some strains of vaccinia virus produces fatal bronchopneumonia, as does aerosol or intranasal inoculation of mice with cowpox virus. Rabbitpox virus causes pneumonia and fatal systemic infections in rabbits and can be naturally transmitted between rabbits by an aerosol route similar to that of VARV in humans. No single animal model recapitulates all known aspects of human Orthopoxvirus infections, and each model has its advantages and disadvantages. This article provides a brief review of the Orthopoxvirus diseases of humans and the key pathologic features of animal models of Orthopoxvirus infections.

Is accelerated partner therapy a feasible and acceptable strategy for rapid partner notification in the UK?: a qualitative study of genitourinary medicine clinic attenders

Partner notification (PN) in the UK is of limited effectiveness. Expedited partner therapy improves PN outcomes but does not comply with existing UK professional guidance. We developed two new strategies, known as accelerated partner therapy (APT), based on elements of PN practice for which there is evidence of efficacy, and which conform to UK prescribing guidance. We explored the acceptability and feasibility of these models qualitatively in genitourinary medicine clinic attenders. Both strategies were viewed favourably. Preference was influenced by age, relationship type, whether participants were delivering or receiving APT and whether the sex partner was aware of the participant's clinic visit. APT provides a new approach to PN, which has strong patient support and complies with existing UK regulations. The complex factors that influence patients' choice of PN method suggest that provision of a range of PN options including APT may be central to improving the effectiveness of PN in the UK.

Members of the Toll-like receptor family of innate immunity pattern-recognition receptors are abundant in the male rat reproductive tract

Protecting developing and maturing spermatozoa and reproductive tissues from microbial damage is an emerging aspect of research in reproductive physiology. Bacterial, viral, and yeast infections of the testis and epididymis can hinder maturation and movement of spermatozoa, resulting in impaired fertility. Toll-like receptors (TLRs) are a broad family of innate immunity receptors that play critical roles in detecting and responding to invading pathogens. Objectives of this study were to determine if organs of the rat male reproductive tract express mRNAs for members of the TLR family, to characterize expression patterns for TLRs in different regions of the epididymis, and to determine if TLR adaptor and target proteins are present in the male reproductive tract. Messenger RNA for Tlr1-Tlr9 was abundantly expressed in testis, epididymis, and vas deferens, as determined by RT-PCR, while Tlr10 and Tlr11 were less abundantly expressed. Tlr mRNA expression showed no region-specific patterns in the epididymis. Immunoblot analysis revealed relatively equal levels of protein for TLRs 1, 2, 4, and 6 in testis, all regions of the epididymis and vas deferens, and lower levels of TLRs 3, 5, and 9-11. TLR7 was primarily detected in the testis. The TLR adapter proteins, myeloid differentiation primary response gene 88 and TLR adaptor molecule 1, as well as v-rel reticuloendotheliosis viral oncogene homolog and NFKBIA, were prominent in testis, epididymis, and vas deferens. The abundant expression of a majority of TLR family members together with expression of TLR adaptors and activation targets provides strong evidence that TLRs play important roles in innate immunity of the male reproductive tract.

Substrate specificity of isopenicillin N synthase

Highly purified isopenicillin N synthase (IPNS) from two sources (naturally occurring in Penicillium chrysogenum and that expressed in Escherichia coli via a cloned gene derived from Cephalosporium acremonium) have been isolated and utilized in vitro to test synthetic modifications of the natural substrate, (L-alpha-amino-delta-adipyl)-L-cysteinyl-D-valine (ACV). A very sensitive procedure utilizing the ability of beta-lactams to induce the synthesis of beta-lactamase was employed to determine whether an ACV analogue could serve as a substrate for IPNS. A wide variety of amino and carboxyl terminal tripeptide substitutions were examined and found to elicit positive beta-lactamase induction profiles. However, none of these modifications were found to function as efficiently as a substrate as ACV. One of the beta-lactam products which was formed from the reaction of IPNS and the tripeptide analogue was independently synthesized and evaluated for antibacterial activity. Modification of the L-cysteine residue in the second position of ACV resulted in tripeptides that were unable to serve as substrates. Conversion of the D-valine residue in the third position of ACV to an aromatic amino acid or to a highly electronegative residue such as trifluorovaline resulted in elimination of substrate activity and creation of an inhibitor of the enzyme.

Management of malignant ventricular arrhythmias using antitachycardia devices

Cardioverter defibrillators were implanted in 26 patients at Charleston Area Medical Center for management of cardiac arrest (7 patients), and drug refractory sustained ventricular tachycardia (19 patients). A variety of operative approaches and concomitant surgical procedures were utilized in the implantation of these devices. No operative deaths occurred. A superficial wound infection was the only operative complication. During the follow-up period (9.3 +/- 5 months), 11 of 26 patients (46 percent) had a defibrillator discharge and one death occurred (3 percent), which was due to heart failure. Patients with malignant ventricular arrhythmias may present with sustained monomorphic ventricular tachycardia with associated syncope, pre-syncope or without any associated symptoms. Unfortunately, cardiac arrest may be the initial presentation. The use of antitachycardia devices such as implantable cardioverter defibrillators and antitachycardia pacemakers has allowed physicians to more successfully treat patients with malignant ventricular arrhythmias. In a significant number of patients with these arrhythmias, such devices are now used as first-line therapy.

Analysis of the role of cysteine residues in isopenicillin N synthetase activity by site-directed mutagenesis

The predicted amino acid sequences of isopenicillin N synthetase from both Cephalosporium acremonium and Penicillium chrysogenum have two cysteine residues in analogous positions (Cys-106 and Cys-255 in the C. acremonium numbering). To examine the role of these cysteine residues in the activity of the C. acremonium enzyme, we used site-directed in vitro mutagenesis to change these cysteine residues to serine residues. Mutation of Cys-255 reduces specific activity approximately equal to 50%, whereas mutation of Cys-106 or mutation of both Cys-106 and Cys-255 reduces specific activity about 97%. This suggests that the cysteines are important but not essential for IPNS activity. Alkylation of IPNS also almost completely inactivated the enzyme, but residual activity could have been due to incomplete alkylation. Atomic substitution via genetic manipulation in this case is a more accurate means of assessing the role of sulfhydryl moieties in enzyme activity.

Isolation, sequence determination and expression in Escherichia coli of the isopenicillin N synthetase gene from Cephalosporium acremonium

The enzyme isopenicillin N synthetase (IPS) catalyses the oxidative condensation of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine (LLD-ACV) to isopenicillin N, which is a central reaction in the pathway to clinically important penicillins and cephalosporins. Here we report the cloning, characterization and expression in Escherichia coli of the gene encoding the IPS protein in Cephalosporium acremonium. The IPS gene was identified by purifying IPS protein, determining the first 23 amino-terminal amino acids, preparing a set of synthetic oligonucleotides encoding a portion of the determined amino-acid sequence, and probing a cosmid genome library with the mixed oligonucleotides. A cosmid hybridizing with the probe was isolated and the IPS gene was localized and sequenced. The IPS gene encodes a polypeptide of relative molecular mass (Mr) 38,416. When this open reading frame was cloned into an E. coli expression vector and inserted into E. coli, the recombinant E. coli produced a new protein co-migrating with authentic IPS as the major protein of the cell (approximately 20% of cell protein). Crude cell extracts condensed LLD-ACV to a penicillinase-sensitive molecule whose antibacterial activity indicated that it was isopenicillin N.

The efficacy of 5-fluorouracil, mitomycin C, and methyl CCNU in advanced gastrointestinal malignancy

50 patients with advanced gastrointestinal malignancies were treated with 5-fluorouracil (5FU), 1-(2-chloroethyl)3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU) and mitomycin C (Mito C). 43 patients, with diagnoses of colorectal, pancreatic or gastric cancer, were evaluable. 13 patients (30%) achieved complete remissions, and 4 achieved partial remissions. The median durations of responses in colorectal, pancreatic and gastric disease were 11.0, 11.0, and 11.5 months, respectively. Survival was definitely prolonged in responding patients with pancreatic and gastric carcinomas. The combination was well tolerated. Mucositis, leukopenia, and thrombocytopenia were the major toxicities that occurred. The quality of life was improved in all responding patients.

Depletion of total hemolytic complement in sera from hamsters bearing herpes simplex type 2-induced tumors

Total hemolytic complement (CH50) levels were compared in sera from normal hamsters and hamsters bearing tumors derived from herpes simplex virus type 2-transformed cells CH50 in normal sera ranged from 160 to 212 while CH50 in tumor bearer sera ranged from 82 to 146. Preincubation of tumor bearer sera with cell surface proteins (CSP) from homologous herpes simplex virus type 2-derived tumor cells resulted in a 66% depletion of CH50 whereas preincubation with heterologous herpes simplex virus type 1-derived tumor CSP resulted in a decrease of 26%. The depletion of CH50 appeared to occur via the classic complement pathway. Similar results were seen using CSP from herpes simplex virus-infected cells although overall depletion of CH50 was considerably less than that seen using tumor cell material. Using the complement subcomponent 1q(C1q)-binding test, tumor bearer sera and tumor bearer sera preincubated with homologous CSP were shown to contain increased levels of immune complexes not present in normal serum. These results indicate that the observed depletion of complement activity in sera from tumor-bearing hamsters could be the result of complement pathway activation by antigen-antibody complexes.