Mustn1 ablation in skeletal muscle results in functional alterations

Mustn1, a gene expressed exclusively in the musculoskeletal system, was shown in previous in vitro studies to be a key regulator of myogenic differentiation and myofusion. Other studies also showed Mustn1 expression associated with skeletal muscle development and hypertrophy. However, its specific role in skeletal muscle function remains unclear. This study sought to investigate the effects of Mustn1 in a conditional knockout (KO) mouse model in Pax7 positive skeletal muscle satellite cells. Specifically, we investigated the potential effects of Mustn1 on myogenic gene expression, grip strength, alterations in gait, ex vivo investigations of isolated skeletal muscle isometric contractions, and potential changes in the composition of muscle fiber types. Results indicate that Mustn1 KO mice did not present any substantial phenotypic changes or significant variations in genes related to myogenic differentiation and fusion. However, an approximately 10% decrease in overall grip strength was observed in the 2-month-old KO mice in comparison to the control wild type (WT), but this decrease was not significant when normalized by weight. KO mice also generated approximately 8% higher vertical force than WT at 4 months in the hindlimb. Ex vivo experiments revealed decreases in about 20 to 50% in skeletal muscle contractions and about 10%-20% fatigue in soleus of both 2- and 4-month-old KO mice, respectively. Lastly, immunofluorescent analyses showed a persistent increase of Type IIb fibers up to 15-fold in the KO mice while Type I fibers decreased about 20% and 30% at both 2 and 4 months, respectively. These findings suggest a potential adaptive or compensatory mechanism following Mustn1 loss, as well as hinting at an association between Mustn1 and muscle fiber typing. Collectively, Mustn1's complex roles in skeletal muscle physiology requires further research, particularly in terms of understanding the potential role of Mustn1 in muscle repair and regeneration, as well as with influence of exercise. Collectively, these will offer valuable insights into Mustn1's key biological functions and regulatory pathways.

Australian radiographers' awareness of cardiac implantable electronic devices (CIEDs) in mammographic imaging

INTRODUCTION

Women presenting for mammography occasionally have pacemakers or other cardiac-implantable electronic devices (CIEDs) in situ. This research investigates Australian radiographers' awareness of CIEDs in the diagnostic and screening settings.

METHODS

A survey of radiographers with mammography experience in Australia was conducted using SurveyMonkey™. Respondents were asked if they could confidently identify images of devices and whether they had imaged them mammographically. A Chi-squared test of independence was used to compare the association between demographics and CIED awareness. A value of p < 0.05 was deemed statistically significant.

RESULTS

There were 220 valid responses. All CIED types had been imaged. Most respondents had imaged a pacemaker (94.5%) and implantable cardioverter-defibrillator (ICD) (85.6%), compared to the three different implantable loop recorders (ILRs) (ILR-1: 63.4%; ILR-2: 14.1%; and IRL-3: 26.9% and the emerging subcutaneous ICDs (S-ICDs) (11.9%). Most respondents felt confident identifying the pacemaker (95%) and the ICD (86.1%). Only 19.4% of respondents could confidently identify the emerging S-ICD.

CONCLUSION

A lack of awareness of new and emerging devices may impact approaches to imaging and present significant risk to patients. The lack of studies comprehensively describing devices and their mammographic appearance to support radiographers' knowledge and awareness highlights an urgent need to progress research in this area.

IMPLICATIONS FOR PRACTICE

As a part of continuing professional development, radiographers performing mammography must ensure they remain up to date with current and emerging technology, including CIEDs. This study has identified a lack of awareness of the different types of CIEDs currently being implanted and imaged, which may translate to unsafe imaging practices. There is an urgent need for further education to bridge this knowledge gap and ensure the safety of practice in imaging women with CIEDs.

FOOTLINE

Mammography: CIED Imaging.

Selected-Lesion Stereotactic Radiosurgery in Treatment of Patients with Multiple Brain Metastases: A Single Institution Retrospective Study

PURPOSE/OBJECTIVE(S)

Stereotactic Radiosurgery (SRS) has been increasingly used as first and subsequent-line treatments for brain metastases. While the appropriate cut-off number of lesions for SRS is still being debated nationally in patients with multiple brain metastases, some institutions use an alternate approach particularly for patients with >10-15 lesions. Selected-lesion SRS (SL-SRS) is where only a subset of lesions are chosen for initial SRS treatment leaving small and clinically inconsequential lesions for treatment using alternate or delayed treatments. This study aims to investigate the patient selection criteria, patient and tumor characteristics and analyze the outcomes in patients receiving SL-SRS for brain metastases at our institution.

MATERIALS/METHODS

Clinical data from patients treated using the SL-SRS approach from 2012-2022 at our institution were retrospectively reviewed. Patients were divided into cohorts based on overall survival from time of SL-SRS treatment and indications for using SL-SRS. We compared the patient characteristics (age, histology, KPS, dsGPA), tumor characteristics (cumulative tumor volumes, tumor dose, number of brain metastases found, number of metastases treated), treatment characteristics (chemotherapy, immunotherapy, previous SRS/ radiation, previous WBRT) and the reason for decision to recommend SL-SRS across these cohort.

RESULTS

A total of 102 patients were treated using the SL-SRS approach. Indications for using SL-SRS were immunotherapy trial (n = 40), CNS penetrating drug options available (n = 18), patient refusing WBRT (n = 6), palliative after prior WBRT/SRS (n = 28), WBRT planned to follow SRS (n = 9). 31 patients were alive at 12 months and 21 patients at 24 months. In patients surviving <12 months - the most common indications for SL-SRS were CNS palliation in the setting of progressive disease after prior WBRT or SRS. Patients in this group had median KPS< = 60 and had predominantly non-small cell carcinoma primary diagnosis. In those patients surviving >12 months - the most common indication for SL-SRS was participation in CNS-penetrant agent clinical trials without WBRT. Patients in this group were more likely to be female, had a median KPS of 90, had predominantly diagnoses of melanoma. Following the SL-SRS treatment, 14 patients required further SRS and 4 patients went on to WBRT in the >12-month survival group. No patients died of CNS progression alone. 10 patients survived 24 months without requiring further CNS radiation.

CONCLUSION

In our institution, SL-SRS has predominantly been used either as palliative treatment at time of disease progression or to facilitate entry onto clinical trial with immunotherapy or potentially CNS-penetrant agents. The latter indication resulted in 47.6% patients surviving >24 month without the need for additional radiation to the CNS and therefore SL-SRS should be considered a feasible, safe and effective alternative to either WBRT or SRS treatment of all radiographically visible brain metastases.

Selected-Lesion SRS as a Novel Strategy in Treatment of Patients with Multiple Brain Metastases

PURPOSE/OBJECTIVE(S)

With the increasing use of intracranial SRS (SRS) for treatment of patients with >10-15 brain metastases treatment; debate remains in the literature about how these patients should be treated. While many advocate for treatment of all lesions with either SRS or whole brain radiation therapy (WBRT), several groups are considering selected-lesion SRS (SL-SRS) where only a subset of intracranial lesions are treated. However, the current practice patterns of SL-SRS are not known.

MATERIALS/METHODS

A survey of 19 questions was created using open-ended and multiple-choice style questions on SL-SRS practices and indications. The survey was distributed to providers in the US and internationally who perform SRS frequently. Ten out of 50 institutions provided responses reflecting the practices of 16 providers. Descriptive statistics was used to compare answers to each question when applicable including percentages and ranges.

RESULTS

SL-SRS was performed at 8/10 institutions, (5 out of 6 US institutions and 3 out of 4 international institutions). Only 2 institutions had established clinical indications for SL-SRS (one in the US and one internationally) and one additional US institution reported clinical trials that require SL-SRS to study efficacy of CNS penetrating targeted therapies. One program reported research protocols for untreated brain metastases that would take priority over SL-SRS (program outside the US). Size of the lesion was cited as the most important factor (90%) when deciding to treat any single lesion. Next, lesion location and focal signs/symptoms were both considered moderately important. 80% ranked distance from prior SRS as the least important factor. Perilesional edema was also less important at most programs (90%). Lesion location and presence of symptoms were also considered important. There were several factors that would encourage providers to consider SL-SRS in a patient. Prior WBRT; progressing systemic disease and CNS-penetrating drug option available; and progressing systemic disease and immunotherapy option available were the most common responses. Most respondents cited "specific request by medical oncology" as well as "cooperative studies in this topic" as factors that might push them towards SL-SRS. Several institutions specified factors beyond the listed options. One institution reported that for patients with >20 lesions, they treated the largest lesions with SRS then follow with WBRT, termed the "pre-WBRT boost." Progression of untreated lesions was the most common reason why providers would bring back patients for additional treatment.

CONCLUSION

The responses to this survey demonstrate that patients with >15-20 intracranial lesions, prior WBRT, and worsening systemic disease with CNS penetrating systemic therapies available are being considered for SL-SRS.

ChatGPT in medical imaging higher education

INTRODUCTION

Academic integrity among radiographers and nuclear medicine technologists/scientists in both higher education and scientific writing has been challenged by advances in artificial intelligence (AI). The recent release of ChatGPT, a chatbot powered by GPT-3.5 capable of producing accurate and human-like responses to questions in real-time, has redefined the boundaries of academic and scientific writing. These boundaries require objective evaluation.

METHOD

ChatGPT was tested against six subjects across the first three years of the medical radiation science undergraduate course for both exams (n = 6) and written assignment tasks (n = 3). ChatGPT submissions were marked against standardised rubrics and results compared to student cohorts. Submissions were also evaluated by Turnitin for similarity and AI scores.

RESULTS

ChatGPT powered by GPT-3.5 performed below the average student performance in all written tasks with an increasing disparity as subjects advanced. ChatGPT performed better than the average student in foundation or general subject examinations where shallow responses meet learning outcomes. For discipline specific subjects, ChatGPT lacked the depth, breadth, and currency of insight to provide pass level answers.

CONCLUSION

ChatGPT simultaneously poses a risk to academic integrity in writing and assessment while affording a tool for enhanced learning environments. These risks and benefits are likely to be restricted to learning outcomes of lower taxonomies. Both risks and benefits are likely to be constrained by higher order taxonomies.

IMPLICATIONS FOR PRACTICE

ChatGPT powered by GPT3.5 has limited capacity to support student cheating, introduces errors and fabricated information, and is readily identified by software as AI generated. Lack of depth of insight and appropriateness for professional communication also limits capacity as a learning enhancement tool.

Mustn1 ablation in skeletal muscle results in increased glucose tolerance concomitant with upregulated GLUT expression in male mice

Glucose homeostasis is closely regulated to maintain energy requirements of vital organs and skeletal muscle plays a crucial role in this process. Mustn1 is expressed during embryonic and postnatal skeletal muscle development and its function has been implicated in myogenic differentiation and myofusion. Whether Mustn1 plays a role in glucose homeostasis in anyway remains largely unknown. As such, we deleted Mustn1 in skeletal muscle using a conditional knockout (KO) mouse approach. KO mice did not reveal any specific gross phenotypic alterations in skeletal muscle. However, intraperitoneal glucose tolerance testing (IPGTT) revealed that 2-month-old male KO mice had significantly lower glycemia than their littermate wild type (WT) controls. These findings coincided with mRNA changes in genes known to be involved in glucose metabolism, tolerance, and insulin sensitivity; 2-month-old male KO mice had significantly higher expression of GLUT1 and GLUT10 transporters, MUP-1 while OSTN expression was lower. These differences in glycemia and gene expression were statistically insignificant after 4 months. Identical experiments in female KO and WT control mice did not indicate any differences at any age. Our results suggest a link between Mustn1 expression and glucose homeostasis during a restricted period of skeletal muscle development/maturation. While this is an observational study, Mustn1's relationship to glucose homeostasis appears to be more complex with a possible connection to other key proteins such as GLUTs, MUP-1, and OSTN. Additionally, our data indicate temporal and sex differences. Lastly, our findings strengthen the notion that Mustn1 plays a role in the metabolic capacity of skeletal muscle.

Cognitive Impairment among the Elderly Population of Rural Haryana, India and its Association with Smoking, Alcohol Intake and Impairments in Vision, Hearing and Activities of Daily Living

Objective: The study aimed to estimate the prevalence of cognitive impairment among elderly people in rural Haryana, India and determine its association with smoking, alcohol consumption and impairments. Material and Methods: This was a community-based cross-sectional study carried out among 575 elderly people aged 60 years and above in the rural field practice area of a medical college in the Haryana state of India. Cognitive impairment was evaluated by the Mini-Cog test. To determine factors associated with cognitive impairment, unadjusted odds ratios with a 95% confidence interval were obtained and binary logistic regression analysis was carried out to calculate adjusted odds ratios. Results: Cognitive impairment was found in 4.5% of the elderly subjects. Those aged 75 years and more, currently not married, illiterate, elderly living alone, current smokers, currently consuming alcohol and elderly with visual, hearing or activities of daily living (ADL) impairments had significantly higher cognitive impairment. Binary logistic regression analysis revealed that illiteracy (adjusted OR=3.173, p-value=0.033), living alone (adjusted OR=6.299, p-value=0.015), current tobacco smoking (adjusted OR=5.393, p-value=0.029), current alcohol drinking (adjusted OR=7.360, p-value=0.001) and ADL impairment (adjusted OR=6.427, p-value=0.001) were independently associated with cognitive impairment. Conclusion: Tobacco smoking, alcohol consumption and ADL impairment were independently associated with cognitive impairment in the elderly people of Haryana state of India. Early screening and timely intervention for signs of cognitive decline may help in improving their quality of life.

Digital Infrastructure Management-Challenges and Opportunities in Post Covid Era

Digital Infrastructure Management-Challenges and Opportunities in Post Covid Era are analyzed in this paper. The 2020 pandemic has been the most serious issue in medical as well as humanity’s history. It has impacted various lives in one way or another. There are multitudes of death cases globally, and the census is pacing at its fastest rate as possible. This lockdown has stressed the medical field and infrastructure and paved its way in the digitalization sector. While observing the lockdown, the world’s economy has faced a steep fall due to sudden and unexpected hampering to the daily work. This opened the door to digitalization. The Digital field has seen a great hike where all the work is shifted from offices to home. It has opened various opportunities but also faces major challenges which expect to furnish after the pandemic crisis. This paper deals with the aspects of digital infrastructure in the post-Covid-19 era.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Whipple's pancreaticoduodenectomy for cancer of the head of the pancreas in a patient with amyotrophic lateral sclerosis: perioperative challenges

The association of amyotrophic lateral sclerosis and pancreatic cancer is rare. Amyotrophic lateral sclerosis is a neurodegenerative disease characterised by pure motor symptoms in the form of progressive muscle weakness and wasting, and can involve the bulbar and respiratory muscles, leading to significant morbidity. Successful surgery for patients with amyotrophic lateral sclerosis for pancreatic cancer has rarely been reported. Surgery in such patients is a dual-edged sword and is decided based on risk-benefit ratio. Patients are at high risk for general anaesthesia because of muscular weakness, increased sensitivity to muscle relaxants and certain anaesthetic drugs. There is a high chance of prolonged postoperative ventilatory support, aspiration pneumonia and pulmonary complications. We report a patient with cancer of the head of the pancreas who underwent successful elective pancreaticoduodenectomy.

Identification of pathways that regulate circadian rhythms using a larval zebrafish small molecule screen

The circadian clock ensures that behavioral and physiological processes occur at appropriate times during the 24-hour day/night cycle, and is regulated at both the cellular and organismal levels. To identify pathways acting on intact animals, we performed a small molecule screen using a luminescent reporter of molecular circadian rhythms in zebrafish larvae. We identified both known and novel pathways that affect circadian period, amplitude and phase. Several drugs identified in the screen did not affect circadian rhythms in cultured cells derived from luminescent reporter embryos or in established zebrafish and mammalian cell lines, suggesting they act via mechanisms absent in cell culture. Strikingly, using drugs that promote or inhibit inflammation, as well as a mutant that lacks microglia, we found that inflammatory state affects circadian amplitude. These results demonstrate a benefit of performing drug screens using intact animals and provide novel targets for treating circadian rhythm disorders.

Inherited and De Novo Genetic Risk for Autism Impacts Shared Networks

We performed a comprehensive assessment of rare inherited variation in autism spectrum disorder (ASD) by analyzing whole-genome sequences of 2,308 individuals from families with multiple affected children. We implicate 69 genes in ASD risk, including 24 passing genome-wide Bonferroni correction and 16 new ASD risk genes, most supported by rare inherited variants, a substantial extension of previous findings. Biological pathways enriched for genes harboring inherited variants represent cytoskeletal organization and ion transport, which are distinct from pathways implicated in previous studies. Nevertheless, the de novo and inherited genes contribute to a common protein-protein interaction network. We also identified structural variants (SVs) affecting non-coding regions, implicating recurrent deletions in the promoters of DLG2 and NR3C2. Loss of nr3c2 function in zebrafish disrupts sleep and social function, overlapping with human ASD-related phenotypes. These data support the utility of studying multiplex families in ASD and are available through the Hartwell Autism Research and Technology portal.

POPPIE: protocol for a randomised controlled pilot trial of continuity of midwifery care for women at increased risk of preterm birth

Background

High rates of preterm births remain a UK public health concern. Preterm birth is a major determinant of adverse infant and longer-term outcomes, including survival, quality of life, psychosocial effects on the family and health care costs. We aim to test whether a model of care combining continuity of midwife care with rapid referral to a specialist obstetric clinic throughout pregnancy, intrapartum and the postpartum period is feasible and improves experience and outcomes for women at increased risk of preterm birth.

Methods

This pilot, hybrid, type 2 randomised controlled implementation trial will recruit 350 pregnant women at increased risk of preterm birth to a midwifery continuity of care intervention or standard care. The intervention will be provided from recruitment (antenatal), labour, birth and the postnatal period, in hospital and community settings and in collaboration with specialist obstetric clinic care, when required. Standard care will be the current maternity care provision by NHS midwives and obstetricians at the study site. Participants will be followed up until 6–8 weeks postpartum. The composite primary outcome is the appropriate initiation of any specified interventions related to the prevention and/or management of preterm labour and birth. Secondary outcomes are related to: recruitment and attrition rates; implementation; acceptability to women, health care professionals and stakeholders; health in pregnancy and other complications; intrapartum outcomes; maternal and neonatal postnatal outcomes; psycho-social health; quality of care; women’s experiences and health economic analysis. The trial has 80% power to detect a 15% increase in the rate of appropriate interventions (40 to 55%). The analysis will be by ‘intention to treat’ analysis.

Discussion

Little is known about the underlying reasons why and how models of midwifery continuity of care are associated with fewer preterm births, better maternal and infant outcomes and more positive experiences; nor how these models of care can be implemented successfully in the health services. This will be the first study to provide direct evidence regarding the effectiveness, implementation and evaluation of a midwifery continuity of care model and rapid access to specialist obstetric services for women at increased risk of preterm birth.

Trial registration

ISRCTN37733900. Retrospectively registered on 21 August 2017.

Light-Dependent Regulation of Sleep and Wake States by Prokineticin 2 in Zebrafish

Light affects sleep and wake behaviors by providing an indirect cue that entrains circadian rhythms and also by inducing a direct and rapid regulation of behavior. While circadian entrainment by light is well characterized at the molecular level, mechanisms that underlie the direct effect of light on behavior are largely unknown. In zebrafish, a diurnal vertebrate, we found that both overexpression and mutation of the neuropeptide prokineticin 2 (Prok2) affect sleep and wake behaviors in a light-dependent but circadian-independent manner. In light, Prok2 overexpression increases sleep and induces expression of galanin (galn), a hypothalamic sleep-inducing peptide. We also found that light-dependent, Prok2-induced sedation requires prokineticin receptor 2 (prokr2) and is strongly suppressed in galn mutants. These results suggest that Prok2 antagonizes the direct wake-promoting effect of light in zebrafish, in part through the induction of galn expression in the hypothalamus.

Serum Levels of Neuroactive Steroids in First-episode Antipsychotic-naïve Schizophrenic Patients and Its Correlation with Aggression: A Case-control Study

BACKGROUND

The evidence of hypothalamic-pituitary-adrenal axis dysfunction in schizophrenia has been reviewed in the context of the stress-diathesis model. Overactivation of this axis leads to altered blood levels of cortisol and dehydroepiandrosterone sulfate (DHEA-S). These neurosteroids in turn act on the hippocampus and interact with gamma-aminobutyric acid and N-methyl-D-aspartate receptors leading to neurotoxicity and may be involved in the neurobiology of aggression. This study aimed to explore the blood level of these neurosteroids and ascertain its correlation with state aggression and psychopathology in first-episode antipsychotic-naïve schizophrenic patients.

METHODS

A total of 30 patients with first-episode schizophrenia along with 20 age- and gender-matched healthy controls participated in the study. Both groups were subjected to serum cortisol and DHEA-S measurement after assessment of psychopathology and aggression on a standardised psychometric scale.

RESULTS

Serum DHEA-S level was significantly higher in the patient group (p = 0.001). No difference was noted between males and females in the patient group (p = 0.93) but female controls had a significantly lower serum DHEA-S level than male controls (p < 0.01). Serum DHEA-S inversely correlated with scores on Modified Overt Aggression Scale (p = 0.01) but not with Positive and Negative Syndrome Scale (p = 0.39) or Clinical Global Impression Scale (p = 0.28).

CONCLUSION

The first-episode antipsychotic-naïve schizophrenic patients showed a significantly higher blood level of DHEA-S compared with healthy controls. Serum DHEA-S level has an inverse relationship with aggression and may serve as a biological adaptive mechanism to antagonise the neuronal damage caused by cortisol.

Morphological and Physiological Interactions Between GnRH3 and Hypocretin/Orexin Neuronal Systems in Zebrafish (Danio rerio)

GnRH neurons integrate internal and external cues to control sexual maturation and fertility. Homeostasis of energy balance and food intake correlates strongly with the status of reproduction. Neuropeptides secreted by the hypothalamus involved in modulating energy balance and feeding may play additional roles in the regulation of reproduction. Hypocretin (Hcrt) (also known as orexin) is one such peptide, primarily controlling sleep/wakefulness, food intake, and reward processing. There is a growing body of evidence indicating that Hcrt/orexin (Hcrt) modulates reproduction through interacting with the hypothalamo-pituitary-gonadal axis in mammals. To explore potential morphological and functional interactions between the GnRH and Hcrt neuronal systems, we employed a variety of experimental approaches including confocal imaging, immunohistochemistry, and electrophysiology in transgenic zebrafish, in which fluorescent proteins are genetically expressed in GnRH3 and Hcrt neurons. Our imaging data revealed close apposition and direct connection between GnRH3 and Hcrt neuronal systems in the hypothalamus during larval development through adulthood. Furthermore, the Hcrt receptor (HcrtR) is expressed in GnRH3 neurons. Electrophysiological data revealed a reversible inhibitory effect of Hcrt on GnRH3 neuron electrical activity, which was blocked by the HcrtR antagonist almorexant. In addition, Hcrt had no effect on the electrical activity of GnRH3 neurons in the HcrtR null mutant zebrafish (HcrtR-/-). Our findings demonstrate a close anatomical and functional relationship between Hcrt and GnRH neuronal systems in zebrafish. It is the first demonstration of a link between neuronal circuits controlling sleeping/arousal/feeding and reproduction in zebrafish, an important animal model for investigating the molecular genetics of development.

Development of a high resolution plantar pressure monitoring pad based on fiber Bragg grating (FBG) sensors

BACKGROUND

High importance is given to plantar pressure monitoring in the field of biomedical engineering for the diagnosis of posture related ailments associated with diseases such as diabetes and gonarthrosis.

OBJECTIVE

This paper presents the proof-of-concept development of a new high resolution plantar pressure monitoring pad based on fiber Bragg grating (FBG) sensors.

METHODS

In the proposed configuration, the FBG sensors are embedded within layers of carbon composite material (CCM) in turn conforming to an arc shape. A total of four such arc shaped sensors are instrumented in the pad at the locations of the forefoot and the hind foot. As a test of the pad, static plantar pressure is monitored on normal subjects under various posture conditions. The pad is evaluated both as a standalone platform as well as a pad inserted inside a standard shoe.

RESULTS

An average pressure sensitivity of 1.2 pm/kPa and a resolution of approximately 0.8 kPa is obtained in this special configuration. The pad is found to be suitable in both configurations- stand-alone pad as well as an insert inside a standard shoe.

CONCLUSION

The proposed set up offers a cost-effective high resolution and accurate plantar pressure measurement system suitable for clinical deployment. The novelty of the developed pressure pad lies in its ability to be used both as platform type as well as inserted in-sole type sensor system.

A Zebrafish Genetic Screen Identifies Neuromedin U as a Regulator of Sleep/Wake States

Neuromodulation of arousal states ensures that an animal appropriately responds to its environment and engages in behaviors necessary for survival. However, the molecular and circuit properties underlying neuromodulation of arousal states such as sleep and wakefulness remain unclear. To tackle this challenge in a systematic and unbiased manner, we performed a genetic overexpression screen to identify genes that affect larval zebrafish arousal. We found that the neuropeptide neuromedin U (Nmu) promotes hyperactivity and inhibits sleep in zebrafish larvae, whereas nmu mutant animals are hypoactive. We show that Nmu-induced arousal requires Nmu receptor 2 and signaling via corticotropin releasing hormone (Crh) receptor 1. In contrast to previously proposed models, we find that Nmu does not promote arousal via the hypothalamic-pituitary-adrenal axis, but rather probably acts via brainstem crh-expressing neurons. These results reveal an unexpected functional and anatomical interface between the Nmu system and brainstem arousal systems that represents a novel wake-promoting pathway.

Porokeratotic Adnexal Ostial Nevus-Report of a Case With Unusual Clinical and Histologic Features

An 11-year-old Tanzanian girl presented with diffuse verrucous lesions of varying morphology, scarring alopecia, and keloid scars over the face with a predilection for the ears. Physical examination revealed dark keratoderma and patches of hypopigmentation near the midline of the dorsal trunk (Figure 1a). Her forearms were densely covered by verrucous lesions with the exception of a clear linear patch on the dorsal aspect of the left forearm (Figure 1b). The perioral area was notable for white spires projecting from verrucous papules (Figure 1c) while the oral mucosa and teeth appeared normal on visual examination. The rest of her body, including the palms and soles, was covered by patchy, scaly lesions of varying severity.

Combined application of FBG and PZT sensors for plantar pressure monitoring at low and high speed walking

BACKGROUND

Clinical monitoring of planar pressure is vital in several pathological conditions, such as diabetes, where excess pressure might have serious repercussions on health of the patient, even to the extent of amputation.

OBJECTIVE

The main objective of this paper is to experimentally evaluate the combined application of the Fibre Bragg Grating (FBG) and the lead zirconate titanate (PZT) piezoceramic sensors for plantar pressure monitoring during walk at low and high speeds.

METHODS

For fabrication of the pressure sensors, the FBGs are embedded within layers of carbon composite material and stacked in an arc shape. From this embedding technique, average pressure sensitivity of 1.3 pm/kPa and resolution of nearly 0.8 kPa is obtained. These sensors are found to be suitable for measuring the static and the low-speed walk generated foot pressure. Simultaneously, PZT patches of size 10 × 10 × 0.3 mm were used as sensors, utilizing the d<formula>_{33}</formula> (thickness) coupling mode. A sensitivity of 7.06 mV/kPa and a pressure resolution of 0.14 kPa is obtained from these sensors, which are found to be suitable for foot pressure measurement during high speed walking and running. Both types of sensors are attached to the underside of the sole of commercially available shoes. In the experiments, a healthy male subject walks/runs over the treadmill wearing the fabricated shoes at various speeds and the peak pressure is measured using both the sensors. Commercially available low-cost hardware is used for interrogation of the two sensor types.

RESULTS

The test results clearly show the feasibility of the FBG and the PZT sensors for measurement of plantar pressure. The PZT sensors are more accurate for measurement of pressure during walking at high speeds. The FBG sensors, on the other hand, are found to be suitable for static and quasi-dynamic (slow walking) conditions. Typically, the measured pressure varied from 400 to 600 kPa below the forefoot and 100 to 1000 kPa below the heel as the walking speed varied from 1 kilometer per hour (kmph) to 7 kmph.

CONCLUSIONS

When instrumented in combination, the two sensors can enable measurements ranging from static to high speed conditions Both the sensor types are rugged, small sized and can be easily embedded in commercial shoes and enable plantar pressure measurement in a cost-effective manner. This research is expected to have application in the treatment of patients suffering from diabetes and gonarthrosis.

Norepinephrine is required to promote wakefulness and for hypocretin-induced arousal in zebrafish

Pharmacological studies in mammals suggest that norepinephrine (NE) plays an important role in promoting arousal. However, the role of endogenous NE is unclear, with contradicting reports concerning the sleep phenotypes of mice lacking NE due to mutation of dopamine β-hydroxylase (dbh). To investigate NE function in an alternative vertebrate model, we generated dbh mutant zebrafish. In contrast to mice, these animals exhibit dramatically increased sleep. Surprisingly, despite an increase in sleep, dbh mutant zebrafish have a reduced arousal threshold. These phenotypes are also observed in zebrafish treated with small molecules that inhibit NE signaling, suggesting that they are caused by the lack of NE. Using genetic overexpression of hypocretin (Hcrt) and optogenetic activation of hcrt-expressing neurons, we also find that NE is important for Hcrt-induced arousal. These results establish a role for endogenous NE in promoting arousal and indicate that NE is a critical downstream effector of Hcrt neurons.

DOI:http://dx.doi.org/10.7554/eLife.07000.001

Although the neural circuits that regulate sleep and wakefulness have yet to be fully identified, the importance of at least two brain regions is well established. These are the hypothalamus, a structure deep within the brain that controls a number of basic activities including hunger, thirst and sleep; and the brainstem, which connects the brain with the spinal cord.

Specific neurons within the hypothalamus and brainstem regulate the sleep–wake cycle by signaling to one another using chemicals called neurotransmitters and neuropeptides. Throughout the day, some hypothalamic neurons release a neuropeptide called hypocretin, which helps maintain wakefulness. Hypocretin acts on neurons within the brainstem and causes them to release other neurotransmitters that promote wakefulness. However, the identity of these molecules is unclear.

One candidate is norepinephrine. Drugs that enhance the effects of norepinephrine increase wakefulness, whereas those that block norepinephrine signaling promote sleep. Despite this, mice that have been genetically modified to lack the enzyme that produces norepinephrine exhibit relatively normal sleep. This may be because in mammals, norepinephrine also has important roles outside the brain, thus complicating the effects of this genetic modification on behavior. Alternatively, while zebrafish that lack norepinephrine are healthy, mice containing this modification die early in development. Treating these mice with a specific drug allows them to survive, but might affect their behavior.

To clarify the role of norepinephrine and its interaction with hypocretin, Singh, Oikonomou and Prober created a new animal model by genetically modifying zebrafish. In contrast to mice, zebrafish that were unable to make norepinephrine slept more than normal fish, although they were also lighter sleepers and were more prone to being startled. A genetic modification that increases hypocretin signaling induces insomnia; Singh, Oikonomou and Prober found that this occurs only in animals with normal levels of norepinephrine. Thus, these experiments indicate that hypocretin does indeed promote wakefulness though norepinephrine.

The work of Singh, Oikonomou and Prober has clarified the role of norepinephrine in regulating the sleep–wake cycle. These findings could help in the development of drugs that target the neurons that make hypocretin, which may improve treatments for sleep disorders.

DOI:http://dx.doi.org/10.7554/eLife.07000.002

Abstract 2398: Precision molecular biomarkers for the surveillance of gynecologic malignancies: Rapid and efficient pipeline for the design and highly sensitive detection of circulating tumor DNA

Gynecologic malignancies affect over 94,000 women in the U.S. and will result in close to 29,000 deaths this year alone. Currently available biomarkers are inadequate for the early detection of disease recurrence. The development of more sensitive and accurate biomarkers represents a critical and immediate necessity towards improving both patient outcome and quality of life. The measurement of circulating tumor DNA (ctDNA), the so-called “liquid biopsy,” represents a powerful emerging technology capable of providing accurate assessment of both tumor behavior and disease burden, and has great potential for revolutionizing our standard approach to tumor surveillance. The ability to translate the various ctDNA detection technologies from the laboratory to the clinic and begin defining clinical utility will in part be determined by the time and cost efficiencies of the pipelines and inherent detection sensitivities.

We have developed a precision-medicine based approach that couples targeted tumor-specific mutation identification for each patient to droplet digital PCR-based (ddPCR) ctDNA detection. Using two rapid-turnaround sequencing panels (targeted full-gene PacBio single-molecule real time (SMRT) long-read sequencing coupled with the Ion AmpliSeq™Cancer Hotspot Panel v2) in lieu of more expensive and time-consuming approaches like whole-exome or whole-genome sequencing, we comprehensively identified tumor mutations for each of our ovarian and endometrial cancer patients by sequencing normal and tumor DNA from each patient. Analysis of an initial cohort of ovarian and endometrial cancer patients resulted in mutation identification frequencies comparable to previously reported data with mutations in TP53, PTEN, and PIK3CA being most frequently represented. Candidate mutations for ctDNA detection were identified for greater than 80% of subjects using this approach. By targeting specific genes, we raise the likelihood that identified tumor mutations are drivers essential to the disease, rather than passenger mutations that may be selected out during disease progression. ctDNA biomarkers specific to each patient's tumor mutations were generated and tested using ddPCR, allowing for detection down to 0.05% mutant allele fraction. ctDNA levels were assessed longitudinally from prospectively collected serums during multiple time points throughout each patient's clinical course and compared to clinical findings and current gold-standard serum and radiologic tests. ctDNA was successfully detected in all subjects; and to our knowledge for the first time in endometrial cancer.

We demonstrate that our molecular approach allows for rapid, highly sensitive and accurate assessment of patient tumor status and, for some patients, is an improved and better predictor of outcome than current gold-standard surveillance strategies.

Citation Format: Elena B. Pereira, Olga Camacho-Vanegas, Sanya Anand, Chanpreet Singh, Andrew Uzilov, Robert Sebra, David Chappell, Peter Dottino, John A. Martignetti. Precision molecular biomarkers for the surveillance of gynecologic malignancies: Rapid and efficient pipeline for the design and highly sensitive detection of circulating tumor DNA. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2398. doi:10.1158/1538-7445.AM2015-2398

Effective communication enhances the patients' endoscopy experience

BACKGROUND

Undergoing an endoscopy is a stressful experience for patients.

AIMS

To audit the endoscopy pathway to improve patient satisfaction.

METHODS

A prospective survey of endoscopy patients to identify system improvements that were then implemented.

RESULTS

The survey was performed before (N = 71) and after (N = 60) process improvements identified by the initial survey. Information provision and staff communication skills were identified for optimisation. Patient anxiety at home was significantly reduced (median 2 vs. 1, p < 0.01). Education of endoscopy staff significantly improved the quality of information provided before and after the procedure with regard to sedation (median 4 vs. 5, p < 0.01), discomfort (median 4 vs. 5, p < 0.01), complications (28 vs. 82 %, p < 0.01), findings (89 vs. 100 %, p < 0.01) and follow-up (73 vs. 90 %, p = 0.015). Gloucester Comfort Scores during endoscopy improved (median 1 vs. 0, p < 0.01) without increasing sedation levels. Patient feelings of invasion/trauma significantly decreased. Overall 95 % of patients were satisfied.

CONCLUSION

Structured information leaflets and improved staff communication skills reduce anxiety and enhance patients' experiences. They are now standard operating procedures.

Four compartment method: a simplified and cost-effective method of noncultured epidermal cell suspension for the treatment of vitiligo

BACKGROUND

Despite continued progress towards an elucidation of pathogenetic pathways in vitiligo, a definitive cure remains elusive. Noncultured epidermal cell suspension (NCECS) is emerging as the treatment of choice for surgical management of both stable and segmental vitiligo. NCECS is very effective in repigmenting stable vitiligo, but the technique requires an expert and the support of a laboratory facility.

OBJECTIVES

To investigate a simplified and more cost-effective method for NCECS.

METHODS

We simplified the conventional NCECS method and made it more cost-effective and simple enough to be performed in the clinic without laboratory equipment. We named this the four compartment (FC) method. Six patients with vitiligo were treated with this FC method.

RESULTS

The FC method for NCECS is highly cost-effective and simple. Six patients with vitiligo were treated and the results showed marked to complete repigmentation in four patients and > 50% repigmentation in two patients in 3 months.

CONCLUSIONS

The FC method is a cost-effective and simple procedure to prepare epidermal cell suspensions. In this modified method we showed that there is no need for pipette, tips, centrifuge tube and most importantly a centrifuge machine or any other expensive laboratory equipment.

A high content assay to assess cellular fitness

A universal process in experimental biology is the use of engineered cells; more often, stably or transiently transfected cells are generated for the purpose. Therefore, it is important that cell health assessment is conducted to check for stress mediated by induction of heat shock proteins (Hsps). For this purpose, we have developed an integrated platform that would enable a direct assessment of transfection efficiency (TE) combined with cellular toxicity and stress response. We make use of automated microscopy and high content analysis to extract from the same well a multiplexed readout to assess and determine optimal chemical transfection conditions. As a proof of concept, we investigated seven commercial reagents, in a matrix of dose and time, to study transfection of an EGFP DNA plasmid into HeLa cells and their consequences on health and fitness; where we scored for cellular proliferation, EGFP positive cells, and induction of Hsp10 and Hsp70 as makers of stress responses. FuGENE HD emerged as the most optimal reagent with no apparent side effects suitable for performing microtiter based miniaturized transfection for both chemical and RNAi screening. In summary, we report on a high content assay method to assess cellular overall fitness upon chemical transfection.

Varied presentation of uterine arteriovenous malformations and their management by uterine artery embolisation

Uterine arteriovenous malformations are rare lesions which have a varied presentation that may range from the patient being asymptomatic to varying degrees of menorrhagia. It can be diagnosed by Doppler sonography but a strong index of suspicion is necessary. Management of this condition depends on presentation and available resources. In asymptomatic patients, we can leave the patients on regular follow-up as many lesions regress spontaneously. In patients with excessive haemorrhage not responding to embolisation or when facilities of embolisation are not available, hysterectomy needs to be done. Uterine artery embolisation should be considered the optimum treatment, as it has a high success rate coupled with few complications and also has fertility-preserving potential. Clinical follow-up usually suffices but sonography may occasionally be required.

The effect of tinted spectacle lenses on contrast sensitivity and colour vision

Aim: Spectacle wearers often prefer tintedlenses to clear or non-tinted lenses for their protection against harmful radiation, improved cos-mesis, enhancement of visual performance and effects on colour vision. Among the available tinted lenses on the market blue, brown and grey tinted spectacle lenses are popular with varying gradesranging from A to D. Due to reduced transmission of light through such lenses, the optical system of the eyes and the environmental vision may be temporarily altered. Colour vision (CV) and con-trast sensitivity (CS) are important aspects of this altered visual world. This study investigated the effect of spectacle lenses of varying grades of tint on CS and CV.Method: The study adopted a pre- and postest research design and a sample of 90 participants were selected from the University of KwaZulu-Natal student population using convenience sam-ling. Each participant was screened for patholgy, dyschromatopsia, severe dry eyes (TBUT<5 seconds), and the presence of any more than low metropia. Thereafter each successful participant was tested for CS and CV with their habitual precription and then tested randomly with a white clear) lens (placebo) and tinted (blue, brown, and grey) spectacle lenses made of CR39 material each having grades A, B and C over their habitual state. Light transmission was 85%, 75%, and 50% for grades A, B, and C respectively. The Functional Acuity Contrast Test (FACT) chart and American Optical Hardy, Rand, and Rittler (AO HRR) were used for the assessment of CS and CV respectively.Results: The data was analysed using the Statistical Package of Social Science (SPSS) version18. Compared to the habitual state, contrast sensitivity was enhanced with all the tinted lensesThe greater enhancement was for low spatial frequencies (LSF) and least for high spatial frequencies (HSF). With all tints Grade C had the least enhancement for very HSF. Many subjects showed no change in CV with any of the lensesused. The grey tint showed greater enhancement of CV as the density increases. Blue and brown tints showed a similar trend with grade B enhancing CV the most while grade C resulted in theleast reduction of CV.Conclusion: Grade A, B, and C of blue, brown and grey tinted spectacle lenses do not alter colour vision significantly but for the selected levels of transmission of the tints used, contrast sensitivity can be improved to some extent.