Robust and Comprehensive Targeted Metabolomics Method for Quantification of 50 Different Primary, Secondary, and Sulfated Bile Acids in Multiple Biological Species (Human, Monkey, Rabbit, Dog, and Rat) and Matrices (Plasma and Urine) Using Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS) Analysis

Bile acids (BAs) are biomolecules synthesized in the liver from cholesterol and are constituents of bile. The in-vivo BA pool includes more than 50 known diverse BAs which are unconjugated, amino acid conjugated, sulfated, and glucuronidated metabolites. Hemostasis of bile acids is known to be highly regulated and an interplay between liver metabolism, gut microbiome function, intestinal absorption, and enterohepatic recirculation. Interruption of BA homeostasis has been attributed to several metabolic diseases and drug induced liver injury (DILI), and their use as potential biomarkers is increasingly becoming important. Speciated quantitative and comprehensive profiling of BAs in various biomatrices from humans and preclinical animal species are important to understand their significance and biological function. Consequently, a versatile one single bioanalytical method for BAs is required to accommodate quantitation in a broad range of biomatrices from human and preclinical animal species. Here we report a versatile, comprehensive, and high throughput liquid chromatography-high resolution mass spectrometry (LC-HRMS) targeted metabolomics method for quantitative analysis of 50 different BAs in multiple matrices including human serum, plasma, and urine and plasma and urine of preclinical animal species (rat, rabbit, dog, and monkey). The method has been sufficiently qualified for accuracy, precision, robustness, and ruggedness and addresses the issue of nonspecific binding of bile acids to plastic for urine samples. Application of this method includes comparison for BA analysis between matched plasma and serum samples, human and animal species differences in BA pools, data analysis, and visualization of complex BA data using BA indices or ratios to understand BA biology, metabolism, and transport.

Evolution and genomic organization of the insect sHSP gene cluster and coordinate regulation in phenotypic plasticity

Background

Conserved syntenic gene complexes are rare in Arthropods and likely only retained due to functional constraint. Numerous sHSPs have been identified in the genomes of insects, some of which are located clustered in close proximity. Previous phylogenetic analyses of these clustered sHSP have been limited to a small number of holometabolous insect species and have not determined the pattern of evolution of the clustered sHSP genes (sHSP-C) in insect or Arthropod lineages.

Results

Using eight genomes from representative insect orders and three non-insect arthropod genomes we have identified that a syntenic cluster of sHSPs (sHSP-C) is a hallmark of most Arthropod genomes. Using 11 genomes from Hymenopteran species our phylogenetic analyses have refined the evolution of the sHSP-C in Hymenoptera and found that the sHSP-C is order-specific with evidence of birth-and-death evolution in the hymenopteran lineage. Finally we have shown that the honeybee sHSP-C is co-ordinately expressed and is marked by genomic features, including H3K27me3 histone marks consistent with coordinate regulation, during honeybee ovary activation.

Conclusions

The syntenic sHSP-C is present in most insect genomes, and its conserved coordinate expression and regulation implies that it is an integral genomic component of environmental response in arthropods.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12862-021-01885-8.

Royal Society of Medicine Surgical Innovation Day Adrian Tanner Prize Winner 2019: Multidisciplinary care and surgical innovation for the benefit of the patient with head and neck cancer of unknown primary

Head and neck carcinoma of unknown primary accounts for approximately 1–5% of all head and neck cancers and presents a genuine diagnostic and therapeutic dilemma. Despite advanced investigations, the primary tumour location remains unknown in up to 40% of these cases. Transoral robotic surgery presents a viable diagnostic and therapeutic option in these patients. This surgical innovation alongside advances in the understanding of head and neck cancer biology means that a multidisciplinary approach in the management of these complex patients is of utmost importance to ensure optimal therapeutic outcomes.

Transoral robotic surgery for the benefit of patients with head and neck cancer of unknown primary: our experience at St George's University Hospital, London

INTRODUCTION

Head and neck carcinoma of unknown primary represents 1-5% of all head and neck cancers and presents a diagnostic and therapeutic dilemma. In approximately 40% of cases, a primary tumour location remains unknown despite investigation. With advancements in our understanding of the role of high-risk human papilloma virus in head and neck cancer, transoral robotic surgery presents an option for diagnosis and therapy.

MATERIALS AND METHODS

This is a retrospective case series from a single centre. Case notes were reviewed for 28 patients who had transoral robotic surgery for head and neck carcinoma of unknown primary between May 2015 and July 2019.

RESULTS

Transoral robotic surgery identified an oropharyngeal primary tumour in 19 of 28 (67.8%) patients. All oropharyngeal primaries were p16 positive. The base of tongue identification rate was 63.2%. Median length of inpatient stay postoperatively was 1.0 day. Normal oral intake resumed within 48 hours in 96% (27/28) of patients. Three patients (10.3%) suffered minor postoperative bleeds that were all managed conservatively.

DISCUSSION

The base of tongue primary identification rate (63.2%) in this series is consistent with that previously reported (43-63%; 95% confidence interval). Primary tumour identification rate if a patient is p16 positive is 86.3% (19/22), with 100% of these being oropharyngeal. We suggest future investigation into p16 status as a means of stratifying patients with head and neck carcinoma of unknown primary for transoral robotic surgery.

CONCLUSION

Transoral robotic base of tongue mucosectomy (or lingual tonsillectomy) is a promising technique that offers a high yield of positive identification for the primary tumour. It is well tolerated with minimal associated morbidity. Our findings are comparable with those in the current literature.

Tracheostomy care and decannulation during the COVID-19 pandemic. A multidisciplinary clinical practice guideline

Purpose

Traditional critical care dogma regarding the benefits of early tracheostomy during invasive ventilation has had to be revisited due to the risk of COVID-19 to patients and healthcare staff. Standard practises that have evolved to minimise the risks associated with tracheostomy must be comprehensively reviewed in light of the numerous potential episodes for aerosol generating procedures. We meet the urgent need for safe practise standards by presenting the experience of two major London teaching hospitals, and synthesise our findings into an evidence-based guideline for multidisciplinary care of the tracheostomy patient.

Methods

This is a narrative review presenting the extensive experience of over 120 patients with tracheostomy, with a pragmatic analysis of currently available evidence for safe tracheostomy care in COVID-19 patients.

Results

Tracheostomy care involves many potentially aerosol generating procedures which may pose a risk of viral transmission to staff and patients. We make a series of recommendations to ameliorate this risk through infection control strategies, equipment modification, and individualised decannulation protocols. In addition, we discuss the multidisciplinary collaboration that is absolutely fundamental to safe and effective practise.

Conclusion

COVID-19 requires a radical rethink of many tenets of tracheostomy care, and controversy continues to exist regarding the optimal techniques to minimise risk to patients and healthcare workers. Safe practise requires a coordinated multidisciplinary team approach to infection control, weaning and decannulation, with integrated processes for continuous prospective data collection and audit.

Use of Google Trends to investigate loss-of-smell-related searches during the COVID-19 outbreak

BACKGROUND

Initial reports describing coronavirus 2019 (COVID-19) were dominated by the presence of cough, breathlessness, and fever; anecdotal reports suggested anosmia may also be a manifestation. We used Google Trends (GT) to investigate whether there was a surge in individuals searching for information related to smell loss during the COVID-19 epidemic in Italy, Spain, the United Kingdom, the United States, Germany, France, Iran, and The Netherlands.

METHODS

GT was used to explore internet activity related to loss of smell in the 8 aforementioned countries. Spearman rank analysis was performed to correlate loss-of-smell-relative search volumes (RSVs), with the increases of daily confirmed cases of COVID-19 and deaths attributed to disease. As a control event, we also performed analysis of smell-related searches during the last UK influenza epidemic of 2009.

RESULTS

In all 8 countries, we observed strong correlations between daily RSVs related to loss of smell, increases of daily COVID-19⁺ cases and deaths ranging from 0.633 to 0.952. All correlations were statistically significant (p < 0.05).

CONCLUSION

There is a strong correlation between the frequency of searches for smell-related information and the onset of COVID-19 infection in Italy, Spain, UK, USA, Germany, France, Iran, and The Netherlands. We hypothesize this may relate to a previously underrecognized symptom.

Sleep in elite swimmers: prevalence of sleepiness, obstructive sleep apnoea and poor sleep quality

Objectives

Limited data suggest that swimmers might be affected by poor quality of sleep significantly. The aim was to explore the prevalence of sleep disturbances in swimmers and possible link between rhinitis and sleep disturbance.

Methods

Study 1 was an observational case–control, questionnaire-based study involving 157 elite and non-elite swimmers, 36 non-swimming athletes and 50 controls. In study 2, we measured sleep quality and duration using actigraphy in 20 elite swimmers. We also looked for presence of sleep-disordered breathing using overnight pulse oximetry monitor.

Results

In study 1, we observed a significant difference in prevalence of excessive daytime sleepiness between groups of elite swimmers and controls. Pittsburgh Sleep Quality Index (PSQI) scores do not suggest that quality of sleep in group of swimmers is impaired. In study 2, we found that prevalence of obstructive sleep apnoea (OSA) in elite swimmers defined as oxygen desaturation index ≥5 was 30%. Analysis of actigraphy data revealed that on nights prior to training days, ‘going to’ bed time was significantly earlier and total sleep time was significantly reduced.

Conclusion

Swimmers and non-swimming athletes suffer significantly more with excessive daytime sleepiness than healthy controls. In elite swimmers, this is likely linked to high prevalence of OSA. PSQI scores do not suggest that quality of sleep in group of swimmers is impaired, but actigraphy shows great variations between sleep pattern preceding training and rest day. This seems to be associated with early-morning sessions which can be a disruptive element of weekly sleep patterns.

High-volume culture and quantitative real-time PCR for the detection of Aspergillus in sputum

OBJECTIVES

Sputum culture is an insensitive method for the diagnosis of pulmonary aspergillosis. Growth of the organism allows identification of the causative species and susceptibility testing, both of which can inform treatment choices. The current practice is to culture an aliquot of diluted sputum. We assessed the value of culturing large volumes of unprocessed sputum, a method that we have termed high-volume culture (HVC).

METHODS

Specimens were processed by conventional culture (using an aliquot of homogenized, diluted sputum on Sabouraud agar at 37°C and 45°C for up to 5 days) and HVC (using undiluted sputum on Sabouraud agar at 30°C for up to 14 days). A separate specimen was tested by quantitative real-time PCR. Antifungal susceptibility testing was performed by the EUCAST standard.

RESULTS

We obtained sputum specimens from 229 individuals with the following conditions: chronic pulmonary aspergillosis (66.8%, 153/229), allergic bronchopulmonary aspergillosis (25.3%, 58/229) and Aspergillus bronchitis (7.9%, 18/229). Individuals with invasive pulmonary aspergillosis were not included. The positivity rate of conventional culture was 15.7% (36/229, 95% CI 11.6%-21.0%) and that of HVC was 54.2% (124/229, 95% CI 47.7%-60.5%) (p < 0.001). The higher positivity rate of HVC was demonstrated regardless of administration of antifungal treatment. Quantitive real-time PCR had an overall positivity rate of 49.2% (65/132, 95% CI 40.9%-57.7%), comparable to that of HVC.

CONCLUSION

Detection of Aspergillus spp. in sputum is greatly enhanced by HVC. HVC allows for detection of azole-resistant isolates that would have been missed by conventional culture. This method can be performed in any microbiology laboratory without the need for additional equipment.

Exercise and Rhinitis in Athletes

Peak sporting performance requires optimal levels of health and fitness. Rhinitis, with its proven detrimental effects on sleep and mood, and its association with asthma, can clearly compromise athletic ability. Nasal health is therefore of key importance to the athlete. While not a limiting factor in a single exercise effort, the effects of nasal dysfunction can have repercussions in the post-exercise recovery period. Furthermore, it is linked with the development of asthma and may increase susceptibility to upper respiratory tract symptoms. This review aims to investigate the physiology of the nose during exercise, examine the relationship between exercise and nasal dysfunction, and consider the impact that dysfunction may have on an athlete. Lastly, the authors describe the diagnosis and treatment of rhinitis in athletes.

C-31 A Meta-analysis Examining Fluency Measures in Depressed Elderly

Objective

Late-life depression (LLD) has been associated with cognitive impairments in domains such as memory, processing speed, and executive functions (e.g., initiation). However, it is unclear whether or not LLD is associated with language fluency difficulties that are often seen in some forms of dementia. Broadly, letter fluency is often observed to be associated with frontal deficits while category fluency is thought to be linked to temporal lobe dysfunction. Both tests are commonly used to assess language in older adults. The current meta-analysis examined potential differences between letter and category fluency in LLD and the robustness of previous findings in this population.

Data Selection

Investigators searched eight databases including PubMed and PsycINFO using terms such as “neuropsychol*,” “late-life,” and “depression.” Studies were excluded if participants were diagnosed with severe mental illness, neurological or other medical conditions that impact neurocognition.

Data Synthesis

Independent coders extracted data from 27 studies (k = 10 letter fluency, k = 17 semantic fluency). The effect size for semantic fluency was g = 0.64 (p < 0.001) with significant heterogeneity I² = 73.53% (Q = 60.45, df = 16, p < 0.001). The effect size for letter fluency was g = 0.49 (p < 0.001) also with significant heterogeneity I² = 52.08% (Q = 18.78, df = 9, p < 0.027).

Conclusions

Depressed individuals exhibited poorer performance on both category and letter fluency when compared to controls. This may indicate that depressed elderly individuals have difficulty with initiating verbal responses regardless of whether these responses rely on semantic networks or executive control.

A-25 Paced Auditory Serial Addition Test in Individuals with Cocaine Versus Methamphetamine Dependence

Objective

Research suggests that cocaine and methamphetamine differ in their impact on executive functions (EF). The Paced Auditory Serial Addition Test (PASAT) is used to assess working memory; a component of EF. The purpose of this meta-analysis was to examine the difference between the effect of these two drugs on PASAT scores.

Data Selection

Three researchers independently searched nine databases (e.g., PsycINFO, Pubmed, ProceedingsFirst), extracted required data, and calculated effect sizes. Inclusion criteria identified studies that had (a) compared cocaine or methamphetamine dependent groups to healthy controls and (b) matched groups on either age, education, or IQ (at least 2 out of 3). Studies were excluded if participants were reported to have Axis I diagnoses (other than cocaine or methamphetamine dependence) or comorbidities known to impact neuropsychological functioning. Six articles were coded and analyzed for the current study.

Data Synthesis

Cocaine studies showed a medium statistically significant effect size (g = 0.370, p = 0.020), while methamphetamine did not (g = 0.198, p = 0.172). There was no heterogeneity in effect sizes for both drugs. Subgroup analysis found no significant difference between the two drugs on the PASAT (Q-between = 0.646, p = 0.421).

Conclusions

In contrast to methamphetamine, cocaine is associated with poorer performance on PASAT. This is in line with previous studies that found that cocaine had more significant impact on EF than methamphetamine. Given the preliminary nature of this meta-analysis and the small number of studies on the topic, future primary studies should directly contrast how these two drugs impact EF.

A-17 Category Test performance in individuals with alcohol versus methamphetamine dependence

Objective

The Category Test (CT) has consistently been found to be sensitive at detecting the effects of alcohol on the brain. However, this test has not been as widely used in examining the effects of methamphetamine. The current meta-analysis compared effect sizes of studies that have examined performance on the CT in alcohol versus methamphetamine dependent participants.

Data selection

Three researchers independently searched nine databases (e.g., PsycINFO, Pubmed, ProceedingsFirst), extracted required data, and calculated effect sizes. Inclusion criteria identified studies that had (a) compared alcohol or methamphetamine dependent groups to healthy controls and (b) matched groups on either age, education, or IQ (at least 2 out of 3). Studies were excluded if participants were reported to have Axis I diagnoses (other than alcohol or methamphetamine dependence) or comorbidities known to impact neuropsychological functioning. Sixteen articles were coded and analyzed for the current study.

Data synthesis

Alcohol studies showed a large effect size (g = 0.745, p < 0.001) while methamphetamine studies evidenced a moderate effect size (g = 0.406, p = 0.001); both without statistically significant heterogeneity (I2 = 0). Subgroup analysis revealed a statistically significant difference between the effect sizes from alcohol versus methamphetamine studies (Q-between = 5.647, p = 0.017).

Conclusions

The CT is sensitive to the effects of both alcohol and methamphetamine and should be considered when examining dependent patients who might exhibit problem solving, concept formation, and set loss difficulties in everyday living.

Agonist-induced membrane nanodomain clustering drives GLP-1 receptor responses in pancreatic beta cells

The glucagon-like peptide-1 receptor (GLP-1R), a key pharmacological target in type 2 diabetes (T2D) and obesity, undergoes rapid endocytosis after stimulation by endogenous and therapeutic agonists. We have previously highlighted the relevance of this process in fine-tuning GLP-1R responses in pancreatic beta cells to control insulin secretion. In the present study, we demonstrate an important role for the translocation of active GLP-1Rs into liquid-ordered plasma membrane nanodomains, which act as hotspots for optimal coordination of intracellular signaling and clathrin-mediated endocytosis. This process is dynamically regulated by agonist binding through palmitoylation of the GLP-1R at its carboxyl-terminal tail. Biased GLP-1R agonists and small molecule allosteric modulation both influence GLP-1R palmitoylation, clustering, nanodomain signaling, and internalization. Downstream effects on insulin secretion from pancreatic beta cells indicate that these processes are relevant to GLP-1R physiological actions and might be therapeutically targetable.

Nanodomain segregation and clustering of the glucagon-like peptide-1 receptor, a key target for type 2 diabetes therapy, is regulated by agonist binding, leading to compartmentalization of downstream signaling and clathrin-dependent internalization and impacting pancreatic beta cell responses.

Unsupervised Learning Techniques for the Investigation of Chronic Rhinosinusitis

OBJECTIVES

This article reviews the principles of unsupervised learning, a novel technique which has increasingly been reported as a tool for the investigation of chronic rhinosinusitis (CRS). It represents a paradigm shift from the traditional approach to investigating CRS based upon the clinically recognized phenotypes of "with polyps" and "without polyps" and instead relies upon the application of complex mathematical models to derive subgroups which can then be further examined. This review article reports on the principles which underlie this investigative technique and some of the published examples in CRS.

METHODS

This review summarizes the different types of unsupervised learning techniques which have been described and briefly expounds upon their useful applications. A literature review of studies which have unsupervised learning is then presented to provide a practical guide to its uses and some of the new directions of investigations suggested by their findings.

RESULTS

The commonest unsupervised learning technique applied to rhinology research is cluster analysis, which can be further subdivided into hierarchical and non-hierarchical approaches. The mathematical principles which underpin these approaches are explained within this article. Studies which have used these techniques can be broadly divided into those which have used clinical data only and that which includes biomarkers. Studies which include biomarkers adhere closely to the established canon of CRS disease phenotypes, while those that use clinical data may diverge from the typical "polyp versus non-polyp" phenotypes and reflect subgroups of patients who share common symptom modifiers.

SUMMARY

Artificial intelligence is increasingly influential in health care research and machine learning techniques have been reported in the investigation of CRS, promising several interesting new avenues for research. However, when critically appraising studies which use this technique, the reader needs to be au fait with the limitations and appropriate uses of its application.

What is the most appropriate treatment for chronic rhinosinusitis?

Chronic rhinosinusitis (CRS) is a common, treatable disease that affects approximately 11% of British adults. It places an enormous burden on patients, with significant detriment to their quality of life, and the health service as it consumes vast numbers of both primary and secondary care resources. However, there is considerable variability in treatment strategies and prescribing practices. This review summarises the key recommendations from landmark guidelines in the treatment of CRS and critically appraises the evidence for treatment.