XPR1: a regulator of cellular phosphate homeostasis rather than a Pi exporter

Phosphate (Pi) is an essential nutrient, and its plasma levels are under tight hormonal control. Uphill transport of Pi into cells is mediated by the two Na-dependent Pi transporter families SLC34 and SLC20. The molecular identity of a potential Pi export pathway is controversial, though XPR1 has recently been suggested by Giovannini and coworkers to mediate Pi export. We expressed XPR1 in Xenopus oocytes to determine its functional characteristics. Xenopus isoforms of proteins were used to avoid species incompatibility. Protein tagging confirmed the localization of XPR1 at the plasma membrane. Efflux experiments, however, failed to detect translocation of Pi attributable to XPR1. We tested various counter ions and export medium compositions (pH, plasma) as well as potential protein co-factors that could stimulate the activity of XPR1, though without success. Expression of truncated XPR1 constructs and individual domains of XPR1 (SPX, transmembrane core, C-terminus) demonstrated downregulation of the uptake of Pi mediated by the C-terminal domain of XPR1. Tethering the C-terminus to the transmembrane core changed the kinetics of the inhibition and the presence of the SPX domain blunted the inhibitory effect. Our observations suggest a regulatory role of XPR1 in cellular Pi handling rather than a function as Pi exporter. Accordingly, XPR1 senses intracellular Pi levels via its SPX domain and downregulates cellular Pi uptake via the C-terminal domain. The molecular identity of a potential Pi export protein remains therefore elusive.

Natural antisense transcripts as versatile regulators of gene expression

Long non-coding RNAs (lncRNAs) are emerging as a major class of gene products that have central roles in cell and developmental biology. Natural antisense transcripts (NATs) are an important subset of lncRNAs that are expressed from the opposite strand of protein-coding and non-coding genes and are a genome-wide phenomenon in both eukaryotes and prokaryotes. In eukaryotes, a myriad of NATs participate in regulatory pathways that affect expression of their cognate sense genes. Recent developments in the study of NATs and lncRNAs and large-scale sequencing and bioinformatics projects suggest that whether NATs regulate expression, splicing, stability or translation of the sense transcript is influenced by the pattern and degrees of overlap between the sense-antisense pair. Moreover, epigenetic gene regulatory mechanisms prevail in somatic cells whereas mechanisms dependent on the formation of double-stranded RNA intermediates are prevalent in germ cells. The modulating effects of NATs on sense transcript expression make NATs rational targets for therapeutic interventions.

Age-Specific Resurgence in Invasive Pneumococcal Disease Incidence in the COVID-19 Pandemic Era and Its Association With Respiratory Virus and Pneumococcal Carriage Dynamics: A Time-Series Analysis

Using multiple national surveillance systems, we found an increase in the incidence of invasive pneumococcal disease during after the relaxation of non-pharmaceutical interventions against COVID-19, which strongly varied by age. Age groups with higher incidence of respiratory syncytial virus and influenza also experienced higher increase in invasive pneumococcal disease incidence, with no change in pneumococcal carriage.

Significant Variations in Double-Stranded RNA Levels in Cultured Skin Cells

Endogenous double-stranded RNA has emerged as a potent stimulator of innate immunity. Under physiological conditions, endogenous dsRNA is maintained in the cell nucleus or the mitochondria; however, if protective mechanisms are breached, it leaches into the cytoplasm and triggers immune signaling pathways. Ectopic activation of innate immune pathways is associated with various diseases and senescence and can trigger apoptosis. Hereby, the level of cytoplasmic dsRNA is crucial. We have enriched dsRNA from two melanoma cell lines and primary dermal fibroblasts, including a competing probe, and analyzed the dsRNA transcriptome using RNA sequencing. There was a striking difference in read counts between the cell lines and the primary cells, and the effect was confirmed by northern blotting and immunocytochemistry. Both mitochondria (10-20%) and nuclear transcription (80-90%) contributed significantly to the dsRNA transcriptome. The mitochondrial contribution was lower in the cancer cells compared to fibroblasts. The expression of different transposable element families was comparable, suggesting a general up-regulation of transposable element expression rather than stimulation of a specific sub-family. Sequencing of the input control revealed minor differences in dsRNA processing pathways with an upregulation of oligoadenylate synthase and RNP125 that negatively regulates the dsRNA sensors RIG1 and MDA5. Moreover, RT-qPCR, Western blotting, and immunocytochemistry confirmed the relatively minor adaptations to the hugely different dsRNA levels. As a consequence, these transformed cell lines are potentially less tolerant to interventions that increase the formation of endogenous dsRNA.

Optimal fracture prediction thresholds for therapy onset, established from FRAX and Garvan algorithms: a longitudinal observation of the population representative female cohort from the RAC-OST-POL Study

The study shows that the use of unified cutoff thresholds to identify high fracture risks by two popular calculators-FRAX and Garvan-leads to a significant discrepancy between the prediction of fractures and their actual prevalence over the period of 10 years. On the basis of the ROC analyses, a proposal of differentiated thresholds is presented. They were established at 6% for FRAX major fracture risk, 1.4% for FRAX hip fracture risk, 14.4% for Garvan any fracture risk, and 8.8% for Garvan hip fracture risk.

PURPOSE/INTRODUCTION

The aim of the study was to verify how much were the tools, designed to predict fracture risks, precise vs. the actual fracture incidence values over a prospective observation.

METHODS

The study group consisted of a population-based postmenopausal sample from the RAC-OST-POL Study. At baseline, there were 978 subjects at the mean age of 66.4 ± 7.8 years and, after a 10-year follow-up, 640 women remained at the mean age of 75.0 ± 6.95 years. At baseline, the fracture risk was established by the FRAX and Garvan tools.

RESULTS

During the observation period, 190 osteoporotic fractures were identified in 129 subjects. When high-risk fracture cutoff thresholds (of 10% for major/any and 3% for hip fractures) were employed, only 19.59% of major fractures and 50% of hip fractures were identified in the high-risk group. For the Garvan tool, the percentage of correctly predicted fractures for any and hip fractures was 86.05% and 71.43%, respectively. Nevertheless, the fracture prediction by the Garvan tool was associated with the qualification of numerous subjects to the high-risk group, who subsequently did not experience a fracture in the 10-year follow-up period (false-positive prediction). Based on the ROC analyses, new high-risk thresholds were proposed individually for each calculator, improving the sensitivity, specificity, and diagnostic accuracy of these tools. They were established at 6% for FRAX major fracture risk, 1.4% for FRAX hip fracture risk, 14.4% for Garvan any fracture risk, and 8.8% for Garvan hip fracture risk.

CONCLUSIONS

The current prospective study enabled to establish new, optimal thresholds for therapy initiation. Such a modified approach may enable a more accurate identification of treatment requiring patients and, in consequence, reduce the number of new fractures.

Antibiotic Resistance of Haemophilus influenzae in Nasopharyngeal Carriage of Children with Acute Otitis Media and in Middle Ear Fluid from Otorrhea

Haemophilus influenzae (Hi) is one of the leading bacteria implicated in childhood acute otitis media (AOM). Recent concerns have been raised about the emergence of Hi-resistant strains. We aimed to analyze the evolution of β-lactam resistance to Hi among strains isolated from nasopharyngeal carriage in children with AOM and in mild ear fluid (MEF) after the spontaneous perforation of the tympanic membrane (SPTM) in France. In this national ambulatory-based cohort study over 16 years, we analyzed the rate of Hi nasopharyngeal carriage and the proportion of β-lactam-resistant Hi strains over time using a segmented linear regression model. Among the 13,865 children (median [IQR] age, 12.7 [9.3-17.3] months; 7400 [53.4%] male) with AOM included from November 2006 to July 2022, Hi was isolated in 7311 (52.7%) children by nasopharyngeal sampling. The proportion of β-lactamase-producing and β-lactamase-negative, ampicillin-resistant (BLNAR) Hi strains in nasopharyngeal carriage remained stable during the study period. Among the 783 children (median [IQR] age, 20 [12.3-37.8] months; 409 [52.2%] male) with SPTM included from October 2015 to July 2022, Hi was isolated in 177 (22.6%) cases by MEF sampling. The proportions of β-lactamase-producing and BLNAR Hi strains did not significantly differ between nasopharyngeal (17.6% and 8.8%, respectively) and MEF (12.6% and 7.4%) samples. Accordingly, amoxicillin remains a valid recommendation as the first-line drug for AOM in France.

Anti-infective treatment of gastro-intestinal tract infections in children

Gastroenteritis is most often viral in origin and Rotavirus and Norovirus most frequently implicated in young children. Stool-based multiplex Polymerase Chain Reaction (PCR) can detect bacteria, viruses or parasites that may or may not be responsible for gastroenteritis (colonization). While the etiological profile of these digestive infections has greatly benefited from PCR, in the absence of underlying pathologies the presence of potential pathogens does not justify anti-infectious treatment. Indeed, very few bacterial causes require antibiotic treatment, apart from shigellosis, severe forms of salmonellosis and a few Campylobacter sp. infections. The development of antibiotic resistance in Salmonella sp., Shigella sp. and Campylobacter sp. is a cause for concern worldwide, limiting therapeutic options. The antibiotics proposed in this guide are in line with the joint recommendations of the European Society of Pediatric Infectious Diseases and the European Society of Pediatric Gastroenterology and Nutrition. Azithromycin is preferentially used to treat infections with Shigella sp. or Campylobacter sp. Ceftriaxone and ciprofloxacin are recommended for salmonellosis requiring antibiotic therapy. Empirical treatments without bacterial identification are not indicated except in cases of severe sepsis or in subjects at risk (e.g., sickle-cell disease). Metronidazole should be prescribed only for acute intestinal amebiasis after microbiological confirmation.

Antimicrobial treatment of ENT infections

Ear, nose and throat (ENT) or upper respiratory tract infections (URTI) are the most common infections in children and the leading causes of antibiotic prescriptions. In most cases, these infections are due to (or are triggered by) viruses and even when bacterial species are implicated, recovery is usually spontaneous. The first imperative is to refrain from prescribing antibiotics in a large number of URTIs: common cold, most cases of sore throat, laryngitis, congestive otitis, and otitis media with effusion. On the contrary, a decision to treat sore throats with antibiotics is based primarily on the positivity of the Group A Streptococcus (GAS) rapid antigen diagnostic tests. For ear infections, only (a) purulent acute otitis media in children under 2 years of age and (b) complicated or symptomatic forms of purulent acute otitis media (PAOM) in older children should be treated with antibiotics. Amoxicillin is the first-line treatment in the most cases of ambulatory ENT justifying antibiotics. Severe ENT infections (mastoiditis, epiglottitis, retro- and parapharyngeal abscesses, ethmoiditis) are therapeutic emergencies necessitating hospitalization and initial intravenous antibiotic therapy.

Pediatric ambulatory pertussis epidemiology in France, recent updates

OBJECTIVES

Following various changes in the vaccine strategy in 2013 and the mandatory vaccination in 2018, we aimed to analyze the vaccination status, age, and source of contamination of pertussis and parapertussis cases in outpatient surveillance.

PATIENTS AND METHODS

Confirmed pertussis and parapertussis cases were enrolled by 35 pediatricians.

RESULTS

From 2014 to 2022, 73 confirmed cases of pertussis (n = 65) and parapertussis (n = 8) were reported. For children below 6 years of age, the number of cases with a 2 + 1 schedule (n = 22) was higher than that of those with a 3 + 1 schedule (n = 7). The age of cases with a 3 + 1 or a 2 + 1 schedule was not significantly different (3.8y ± 1.4 vs 4.2y ± 1.5). The main source of contamination was either adults or adolescents.

CONCLUSION

Vaccination status and source of contamination are crucial to study the impact of vaccination recommendations.

Surveillance of noninvasive group A Streptococcus infections in French ambulatory pediatrics before and during the COVID-19 pandemic: a prospective multicenter study from 2018-2022

OBJECTIVES

We evaluated the burden of noninvasive group A Streptococcus (GAS) infections in ambulatory pediatrics before and during the COVID-19 pandemic in France.

METHODS

We analyzed data from a national network of ambulatory pediatricians between 2018 and 2022. Clinicians evaluating children ≤15 years old for tonsillopharyngitis, perianal infections, paronychia/blistering dactylitis, and scarlet fever were invited to perform a rapid antigen detection test (RADT) for GAS. Monthly incidence of noninvasive GAS infections per 10,000 visits was modeled using time series analysis, considering two breakpoints: March 2020 (first national lockdown) and March 2022 (end of mandatory mask-wearing in schools).

RESULTS

Over the study period, 125 pediatricians recorded 271,084 infectious episodes. GAS-related illnesses represented 4.3% of all infections. In March 2020, the incidence of GAS diseases decreased by 84.5% (P <0.001), with no significant trend until March 2022. After March 2022, the incidence significantly increased (+23.8% per month, P <0.001), with similar patterns across all monitored GAS-related diseases.

CONCLUSION

By using routine clinical data and RADTs, we have monitored changes in the incidence of noninvasive GAS infections in ambulatory pediatrics. COVID-19 mitigation measures have had a major impact on the epidemiology of noninvasive GAS infections, but their relaxation was followed by a surge above baseline levels.

Clinical and Functional Assessment of Digenicity in Renal Phosphate Wasting

Apart from increased fluid intake, patients with kidney stone disease (KSD) due to renal phosphate wasting require specific metaphylaxis. NaPi2a, NaPi2c, and NHERF1 regulate plasma phosphate concentration by reabsorbing phosphate in proximal kidney tubules and have been found altered in monogenic hypophosphatemia with a risk of KSD. In this study, we aimed at assessing the combined genetic alterations impacting NaPi2a, NaPi2c, and NHERF1. Therefore, we screened our hereditary KSD registry for cases of oligo- and digenicity, conducted reverse phenotyping, and undertook functional studies. As a result, we identified three patients from two families with digenic alterations in NaPi2a, NaPi2c, and NHERF1. In family 1, the index patient, who presented with severe renal calcifications and a bone mineralization disorder, carried digenic alterations affecting both NaPi transporter 2a and 2c. Functional analysis confirmed an additive genetic effect. In family 2, the index patient presented with kidney function decline, distinct musculature-related symptoms, and intracellular ATP depletion. Genetically, this individual was found to harbor variants in both NaPi2c and NHERF1 pointing towards genetic interaction. In summary, digenicity and gene dosage are likely to impact the severity of renal phosphate wasting and should be taken into account in terms of metaphylaxis through phosphate substitution.

Therapeutic inertia during isotretinoin treatment of juvenile acne by dermatologists, paediatricians and general practitioners

BACKGROUND

Isotretinoin is an effective treatment for severe juvenile acne, but it appears to be underused in relation to the recommendations. Therapeutic inertia is defined as a failure to initiate or intensify treatment even when warranted by the recommendations. The aim of this study was to investigate therapeutic inertia among dermatologists (D), paediatricians (P), and general practitioners (GPs) in initiating isotretinoin for moderate-to-very severe juvenile acne.

METHODS

Data were collected using a questionnaire distributed to French physicians through medical societies via Internet. The questions explored the role in inertia of factors related to physicians, patients, parents, and the healthcare system, and evaluated barriers and facilitators to prescribing isotretinoin.

RESULTS

In all, 768 physicians responded to the survey (528 D, 178P, and 61 GPs; mean age: 51 years; women: 78 %). Their responses revealed that 99 % of dermatologists felt comfortable prescribing isotretinoin, compared with 8 % and 15 % of paediatricians and GPs (p < 0.05); 93 % of dermatologists were aware of the current guidelines compared with 37 % of paediatricians and GPs. Under 50 % of the physicians had received training on acne in the previous 3 years, regardless of specialty. The most frequently identified factors for inertia were concerns over the psychological consequences of the treatment in adolescents, exclusive requests from parents, and patient unavailability. Paediatricians reported having insufficient knowledge of current recommendations, a lack of training, and a tendency to anticipate poor compliance. Paediatricians and GPs considered that access to first-time prescriptions and peer-to-peer exchanges would constitute facilitating factors in their use of isotretinoin.

DISCUSSION

Concerns over the psychiatric consequences of isotretinoin in adolescents, the need for frequent follow-up, and lack of continuing medical education were identified as factors favouring inertia in the initiation of isotretinoin treatment in patients with moderate-to-very severe juvenile acne, particularly among paediatricians and GPs. Potential strategies to overcome these barriers include regular training, simplified recommendations in French, and access to first-time prescription for paediatricians and GPs.

Trends in pediatric ambulatory community acquired infections before and during COVID-19 pandemic: A prospective multicentric surveillance study in France

Background

Covid-19 pandemic control has imposed several non-pharmaceutical interventions (NPIs). Strict application of these measures has had a dramatic reduction on the epidemiology of several infectious diseases. As the pandemic is ongoing for more than 2 years, some of these measures have been removed, mitigated, or less well applied. The aim of this study is to investigate the trends of pediatric ambulatory infectious diseases before and up to two years after the onset of the pandemic.

Methods

We conducted a prospective surveillance study in France with 107 pediatricians specifically trained in pediatric infectious diseases. From January 2018 to April 2022, the electronic medical records of children with an infectious disease were automatically extracted. The annual number of infectious diseases in 2020 and 2021 was compared to 2018-2019 and their frequency was compared by logistic regression.

Findings

From 2018 to 2021, 185,368 infectious diseases were recorded. Compared to 2018 (n=47,116) and 2019 (n=51,667), the annual number of cases decreased in 2020 (n=35,432) by about a third. Frequency of scarlet fever, tonsillopharyngitis, enteroviral infections, bronchiolitis, and gastroenteritis decreased with OR varying from 0·6 (CI95% [0·5;0·7]) to 0·9 (CI95% [0·8;0·9]), p<0·001. In 2021, among the 52,153 infectious diagnoses, an off-season rebound was observed with increased frequency of enteroviral infections, bronchiolitis, gastroenteritis and otitis with OR varying from 1·1 (CI95% [1·0;1·1]) to 1·5 (CI95% [1·4;1·5]), p<0·001.

Interpretation

While during NPIs strict application, the overall frequency of community-acquired infections was reduced, after relaxation of these measures, a rebound of some of them (enteroviral infections, bronchiolitis, gastroenteritis, otitis) occurred beyond the pre-pandemic level. These findings highlight the need for continuous surveillance of infectious diseases, especially insofar as future epidemics are largely unpredictable.

Funding

ACTIV, AFPA, GSK, MSD, Pfizer and Sanofi.

Prediction of Acute and Chronic Mastitis in Dairy Cows Based on Somatic Cell Score and Mid-Infrared Spectroscopy of Milk

Simple Summary

Mid-infrared (MIR) spectroscopy is the method of choice to determine milk components like fat, protein and urea. We examined the potential of MIR spectra analyses for the prediction of clinical mastitis events of dairy cows additionally, or alternatively, to somatic cell count, which is routinely used as an indicator for mastitis monitoring. Prediction models based on MIR spectra and a somatic cell count-derived score (SCS) were developed and compared. A model based on MIR spectra and SCS proved more accurate at predicting mastitis than models based on either indicator alone. Consequently, MIR spectra analyses add extra value in the prediction of clinical mastitis, making them potentially useful for dairy farm management and as an auxiliary trait for the genetic evaluation of udder health.

Abstract

Monitoring for mastitis on dairy farms is of particular importance, as it is one of the most prevalent bovine diseases. A commonly used indicator for mastitis monitoring is somatic cell count. A supplementary tool to predict mastitis risk may be mid-infrared (MIR) spectroscopy of milk. Because bovine health status can affect milk composition, this technique is already routinely used to determine standard milk components. The aim of the present study was to compare the performance of models to predict clinical mastitis based on MIR spectral data and/or somatic cell count score (SCS), and to explore differences of prediction accuracies for acute and chronic clinical mastitis diagnoses. Test-day data of the routine Austrian milk recording system and diagnosis data of its health monitoring, from 59,002 cows of the breeds Fleckvieh (dual purpose Simmental), Holstein Friesian and Brown Swiss, were used. Test-day records within 21 days before and 21 days after a mastitis diagnosis were defined as mastitis cases. Three different models (MIR, SCS, MIR + SCS) were compared, applying Partial Least Squares Discriminant Analysis. Results of external validation in the overall time window (−/+21 days) showed area under receiver operating characteristic curves (AUC) of 0.70 when based only on MIR, 0.72 when based only on SCS, and 0.76 when based on both. Considering as mastitis cases only the test-day records within 7 days after mastitis diagnosis, the corresponding areas under the curve were 0.77, 0.83 and 0.85. Hence, the model combining MIR spectral data and SCS was performing best. Mastitis probabilities derived from the prediction models are potentially valuable for routine mastitis monitoring for farmers, as well as for the genetic evaluation of the trait udder health.

Cardiovascular Regulation During Acute Gravitational Changes with Exhaling on Exertion

During gravitational changes or changes in the direction of action in relation to the body, fluid displacements can be observed. In special cases different breathing maneuvers (e. g., exhaling on exertion; Ex-Ex) are used to counteract acute fluid shifts. Both factors have a significant impact on cardiovascular regulation. Eight healthy male subjects were tested on a tilt seat, long arm human centrifuge, and parabolic flight. The work aims to investigate the effect of exhaling on exertion on the cardiovascular regulation during acute gravitational changes compared to normal breathing. Possible interactions and differences between conditions (Ex-Ex, normal breathing) for the parameters V’O₂ , V’_E , HR, and SV were analysed over a 40 s period by a three-way ANOVA. Significant (p≤0.05) effects for all main factors and interactions between condition and time as well as maneuver and time were found for all variables. The exhaling on exertion maneuver had a significant influence on the cardiovascular response during acute gravitational and positional changes. For example, the significant increase of V’O2 at the end of the exhalation on exertion maneuver indicates an increased lung circulation as a result of the maneuver.

Coxsackievirus A6 Recombinant Subclades D3/A and D3/H Were Predominant in Hand-Foot-And-Mouth Disease Outbreaks in the Paediatric Population, France, 2010–2018

Coxsackievirus A6 (CVA6) emerged as the most common enterovirus of seasonal outbreaks of hand-foot-and-mouth disease (HFMD). We investigated CVA6 genetic diversity among the clinical phenotypes reported in the paediatric population during sentinel surveillance in France between 2010 and 2018. CVA6 infection was confirmed in 981 children (mean age 1.52 years [IQR 1.17–2.72]) of whom 564 (58%) were males. Atypical HFMD was reported in 705 (72%) children, followed by typical HFMD in 214 (22%) and herpangina in 57 (6%) children. Throat specimens of 245 children were processed with a target-enrichment new-generation sequencing approach, which generated 213 complete CVA6 genomes. The genomes grouped within the D1 and D3 clades (phylogeny inferred with the P1 genomic region). In total, 201 genomes were classified among the recombinant forms (RFs) A, B, F, G, H, and N, and 12 genomes were assigned to 5 previously unreported RFs (R–V). The most frequent RFs were A (58%), H (19%), G (6.1%), and F (5.2%). The yearly number of RFs ranged between 1 (in 2012 and 2013) and 6 (2018). The worldwide CVA6 epidemic transmission began between 2005 and 2007, which coincided with the global spread of the recombinant subclade D3/RF-A.

The association of depression and all-cause mortality: Explanatory factors and the influence of gender

BACKGROUND

The association of depression with mortality and the significance of explanatory factors, in particularly gender, have remained an issue of debate. We therefore aimed to estimate the effect of depression on all-cause mortality, to examine potential explanatory factors and to assess effect modification by gender.

METHODS

We used Cox regression models to estimate the effect of depression on mortality based on data from the Gutenberg Health Study, which is a prospective cohort study of the adult population in the districts of Mainz and Mainz-Bingen, Germany. Baseline assessment was between 2007 and 2012. Effect modification by gender was measured on both additive and multiplicative scales.

RESULTS

Out of 14,653 participants, 7.7% were depressed according to Patient Health Questionnaire 9 (PHQ-9), and 1,059 (7.2%) died during a median follow-up of 10.7 years. Depression elevated the risk of mortality in men and women in age-adjusted models (HR: 1.41, 95%-CI: 1.03-1.92; resp. HR: 1.96, 95%-CI: 1.43-2.69). Adjustment for social status, physical health and lifestyle covariates attenuated the effect and in the fully-adjusted model the hazard ratio was 0.96 (95%-CI: 0.69-1.33) in men and 1.53 (95%-CI: 1.10-2.12) in women. For effect modification by gender, the measure on multiplicative interaction was 0.68 (95%-CI 0.44-1.07) and on additive interaction was RERI=-0.47 (95%-CI -1.24-0.30).

LIMITATIONS

The PHQ-9 is a single self-report measure of depression reflecting symptoms of the past two weeks, limiting a more detailed assessment of depression and course of symptoms, which likely affects the association with mortality.

CONCLUSIONS

Depression elevates mortality by multifactorial pathways, which should be taken into account in the biopsychosocially informed treatment of depression. Effect modification by gender was not statistically significant.

Low Ambient Temperature Exposition Impairs the Accuracy of a Non-invasive Heat-Flux Thermometer

Background

Indirect core body temperature (CBT) monitoring from skin sensors is gaining attention for in-field applications thanks to non-invasivity, portability, and easy probe positioning. Among skin sensors, heat-flux devices, such as the so-called Double Sensor (DS), have demonstrated reliability under various experimental and clinical conditions. Still, their accuracy at low ambient temperatures is unknown. In this randomized cross-over trial, we tested the effects of cold temperature exposition on DS performance in tracking CBT.

Methods

Twenty-one participants were exposed to a warm (23.2 ± 0.4°C) and cold (−18.7 ± 1.0°C) room condition for 10 min, following a randomized cross-over design. The accuracy of the DS to estimate CBT in both settings was assessed by quantitative comparison with esophageal (reference) and tympanic (comparator) thermometers, using Bland–Altman and correlation analyses (Pearson’s correlation coefficient, r, and Lin’s concordance correlation coefficient, CCC).

Results

In the warm room setting, the DS showed a moderate agreement with the esophageal sensor [bias = 0.09 (−1.51; 1.69) °C, r = 0.40 (p = 0.069), CCC = 0.22 (−0.006; 0.43)] and tympanic sensor [bias = 2.74 (1.13; 4.35) °C, r = 0.54 (p < 0.05), CCC = 0.09 (0.008; 0.16)]. DS accuracy significantly deteriorated in the cold room setting, where DS temperature overestimated esophageal temperature [bias = 2.16 (−0.89; 5.22) °C, r = 0.02 (0.94), CCC = 0.002 (−0.05; 0.06)]. Previous exposition to the cold influenced temperature values measured by the DS in the warm room setting, where significant differences (p < 0.00001) in DS temperature were observed between randomization groups.

Conclusion

DS accuracy is influenced by environmental conditions and previous exposure to cold settings. These results suggest the present inadequacy of the DS device for in-field applications in low-temperature environments and advocate further technological advancements and proper sensor insulation to improve performance in these conditions.

Overview of meningococcal epidemiology and national immunization programs in children and adolescents in 8 Western European countries

BACKGROUND

In Europe, meningococcal (Men) vaccines are available against 5 of the 6 serogroups responsible of nearly all cases of invasive meningococcal disease (IMD). Meningococcal vaccination has been introduced in the national immunization programs (NIPs) for children and adolescents of numerous European countries, but with no consistent strategy across countries.

OBJECTIVES

To describe IMD epidemiology, NIPs, and vaccination coverage rates (VCRs) in children and adolescents in 8 Western European countries.

METHODS

Epidemiological data (from 1999 to 2019), NIPs regarding meningococcal vaccination status, and VCRs were collected from the European Centre for Disease Prevention and Control (ECDC) and/or national websites.

RESULTS

MenB was the most common serogroup. In Belgium, Spain, France, the Netherlands, the United Kingdom (UK), and Portugal, incidence was greater for MenW than MenC. In 2019, MenB risk was covered in 2 countries (Italy, UK). MenC risk was covered in all countries, via MenC only (countries: N = 3), MenACWY only (N = 2), or MenC (infants/children) and MenACWY (adolescents) (N = 3) vaccination. VCRs were higher in children than adolescents.

CONCLUSION

Our study confirmed the diversity of NIPs, including in neighboring European countries with similar factors like economic resources and epidemiological risk, thus indicating that other factors underlie NIPs. Convergence toward a more common immunization program including MenACWY and MenB vaccination would promote equity and safe travel regarding infectious diseases for young people, and possibly improve the understanding of vaccination by patients and healthcare professionals.

Variations in Guidelines for Diagnosis of Child Physical Abuse in High-Income Countries: A Systematic Review

Importance

The highly variable practices observed regarding the early detection and diagnostic workup of suspected child physical abuse contribute to suboptimal care and could be partially related to discrepancies in clinical guidelines.

Objective

To systematically evaluate the completeness, clarity, and consistency of guidelines for child physical abuse in high-income countries.

Evidence Review

For this systematic review, national or regional guidelines that were disseminated from 2010 to 2020 related to the early detection and diagnostic workup of child physical abuse in infants aged 2 years or younger by academic societies or health agencies in high-income countries were retrieved. The definitions of sentinel injuries and the recommended diagnostic workup (imaging and laboratory tests) for child physical abuse were compared. Data were analyzed from July 2020 to February 2021.

Findings

Within the 20 included guidelines issued in 15 countries, 168 of 408 expected statements (41%) were missing and 10 statements (4%) were unclear. Among 16 guidelines characterizing sentinel injuries, all of them included skin injuries, such as bruises, hematoma, or burns, but only 8 guidelines (50%) included intraoral injuries and fractures. All 20 guidelines agreed on the indication for radiological skeletal survey, head computed tomography, and head magnetic resonance imaging but differed for those of bone scintigraphy, follow-up skeletal survey, spinal magnetic resonance imaging, cranial ultrasonography, chest computed tomography, and abdominal ultrasonography and computed tomography. Additionally, 16 guidelines agreed on exploring primary hemostasis and coagulation but not on the tests to perform, and 8 guidelines (50%) mentioned the need to investigate bone metabolism.

Conclusions and Relevance

These findings suggest that guidelines for the diagnosis of child physical abuse in infants were often clear but lacked completeness and were discrepant on major issues. These results may help identify priorities for well-designed original diagnostic accuracy studies, systematic reviews, or an international consensus process to produce clear and standardized guidelines to optimize practices and infant outcomes.

High frame rate speckle tracking echocardiography to assess diastolic function

Background

Left ventricular (LV) strain rate (SR) during isovolumic relaxation (SRIVR) and early diastolic filling (SRe) has previously been shown to correlate with the invasive gold standard for LV diastolic function (i.e. the time constant of LV pressure decay tau). However, the translation of these biomarkers to the clinic has been hampered by technical limitations. Indeed, conventional speckle tracking (STE) is limited by its temporal resolution, whereas tissue Doppler imaging (TDI) is angle-dependent, labor-intensive and thus rarely used clinically nowadays.

Purpose

The aim of this study was to show that these limitations could be overcome by using a recently proposed STE algorithm operating on high frame rate (HFR) imaging data.

Methods

37 subjects (age: 64±12, 81% male) were included in the study; 16 had cardiac amyloidosis, 12 were undergoing clinically indicated left and/or right heart cardiac catheterization and 9 were healthy volunteers. Since the sequence of left ventricular activation and thus the repolarization process (i.e. relaxation) starts at mid septum, we measured SRIVR and SRe in the mid septal segment in an apical 4 chamber view using a commercially available clinical system with: (1) TDI (frame rate (FR) ∼142 Hz); (2) STE (FR ∼65 Hz). Moreover, subjects were scanned with HD-PULSE, an experimental high frame ultrasound scanner (FR ∼915 Hz) and then a manually placed contour was tracked during the cardiac cycle by a custom-made 2D HFR STE algorithm, to compute and extract SRIVR and SRe from the mid septum. Since TDI is considered the reference method to assess SR, conventional as well as HFR STE values were correlated against the TDI SR values.

Results

In 3 subjects, SRIVR could not be reliably assessed with the clinical STE approach, which we attributed to the relatively low temporal resolution of the images; all other measurements could be made in all subjects. For both biomarkers, HFR STE values correlated better with the TDI reference measurements than the clinical STE estimates (Fig.1). The latter estimates showed a systematic underestimation (bias −0.19 1/s (p&lt;0.01) and −0.46 1/s (p&lt;0.01) for SRIVR and SRe respectively) while no significant bias was observed for the HFR STE values. Similarly, the limits of agreement of the HFR STE values were narrower (−0.45 to +0.54 1/s and −0.94 to +0.86 1/s) than those of the clinical STE measurements (−0.85 to +0.48 1/s and −1.32 to +0.41 1/s).

Conclusions

These results show that HFR STE offers a reliable way to assess novel biomarkers of diastolic function in a user-friendly manner and can therefore facilitate their incorporation to the clinical practice.

Funding Acknowledgement

Type of funding sources: None.

Comparative study on tertiary contacts and folding of RNase P RNAs from a psychrophilic, a mesophilic/radiation-resistant, and a thermophilic bacterium

In most bacterial type A RNase P RNAs (P RNAs), two major loop-helix tertiary contacts (L8-P4 and L18-P8) help to orient the two independently folding S- and C-domains for concerted recognition of precursor tRNA substrates. Here, we analyze the effects of mutations in these tertiary contacts in P RNAs from three different species: (i) the psychrophilic bacterium Pseudoalteromonas translucida (Ptr), (ii) the mesophilic radiation-resistant bacterium Deinococcus radiodurans (Dra), and (iii) the thermophilic bacterium Thermus thermophilus (Tth). We show by UV melting experiments that simultaneous disruption of these two interdomain contacts has a stabilizing effect on all three P RNAs. This can be inferred from reduced RNA unfolding at lower temperatures and a more concerted unfolding at higher temperatures. Thus, when the two domains tightly interact via the tertiary contacts, one domain facilitates structural transitions in the other. P RNA mutants with disrupted interdomain contacts showed severe kinetic defects that were most pronounced upon simultaneous disruption of the L8-P4 and L18-P8 contacts. At 37°C, the mildest effects were observed for the thermostable Tth RNA. A third interdomain contact, L9-P1, makes only a minor contribution to P RNA tertiary folding. Furthermore, D. radiodurans RNase P RNA forms an additional pseudoknot structure between the P9 and P12 of its S-domain. This interaction was found to be particularly crucial for RNase P holoenzyme activity at near-physiological Mg²⁺ concentrations (2 mM). We further analyzed an exceptionally stable folding trap of the G,C-rich Tth P RNA.

Head circumference from birth to five years in France: New national reference charts and comparison to WHO standards

Background

The monitoring of head circumference (HC) is essential to early detect any conditions affecting its growth in early childhood. A positive secular trend and regional specificities in HC suggested the need to provide updated national HC reference growth charts.

Methods

We extracted all growth data collected from 42 primary-care physicians from across the French metropolitan territory who used the same electronic medical-records software. We selected HC measurements up to age five years for all children who were born after 1990 with birth weight > 2500 g. We derived new HC growth charts by using Generalized Additive Models for Location, Scale and Shape, then externally validated them until 30 months of age by comparison with the national population-based Étude Longitudinale Française depuis l'Enfance (ELFE) birth cohort and compared them to previous French and WHO growth charts.

Findings

With 973,869 HC measurements from 157,762 children, new calibrated HC growth charts from birth to age five years were generated. The new HC growth charts showed good external fit by comparison with the ELFE birth cohort. As compared with the new HC growth charts, the previous French and WHO growth charts mean HC z-scores were, respectively, -0.4 and -0.6 SD for girls and -0.2 and -0.6 SD for boys.

Interpretation

We produced and validated national calibrated HC growth charts by using a novel big-data approach applied to data routinely collected in clinical practice. Comparison with previous French and WHO growth charts confirmed a positive secular trend since the 1960s and regional specificities.

Funding

The French Ministry of Health; Laboratoires Guigoz—General Pediatrics section of the French Society of Pediatrics—Paediatric Epidemiological Research Group; the French Association of Ambulatory Pediatrics; and educational grant from the Regional Health Agency of Ile-de-France.

Multiple Breeds and Countries' Predictions of Mineral Contents in Milk from Milk Mid-Infrared Spectrometry

Measuring the mineral composition of milk is of major interest in the dairy sector. This study aims to develop and validate robust multi-breed and multi-country models predicting the major minerals through milk mid-infrared spectrometry using partial least square regressions. A total of 1281 samples coming from five countries were analyzed to obtain spectra and in ICP-AES to measure the mineral reference contents. Models were built from records coming from four countries (n = 1181) and validated using records from the fifth country, Austria (n = 100). The importance of including local samples was tested by integrating 30 Austrian samples in the model while validating with the remaining 70 samples. The best performances were achieved using this second set of models, confirming the need to cover the spectral variability of a country before making a prediction. Validation root mean square errors were 54.56, 63.60, 7.30, 59.87, and 152.89 mg/kg for Na, Ca, Mg, P, and K, respectively. The built models were applied on the Walloon milk recording large-scale spectral database, including 3,510,077. The large-scale predictions on this dairy herd improvement database provide new insight regarding the minerals' variability in the population, as well as the effect of parity, stage of lactation, breeds, and seasons.

Widespread formation of double-stranded RNAs in testis

The testis transcriptome is highly complex and includes RNAs that potentially hybridize to form double-stranded RNA (dsRNA). We isolated dsRNA using the monoclonal J2 antibody and deep-sequenced the enriched samples from testes of juvenile Dicer1 knockout mice, age-matched controls, and adult animals. Comparison of our data set with recently published data from mouse liver revealed that the dsRNA transcriptome in testis is markedly different from liver: In testis, dsRNA-forming transcripts derive from mRNAs including promoters and immediate downstream regions, whereas in somatic cells they originate more often from introns and intergenic transcription. The genes that generate dsRNA are significantly expressed in isolated male germ cells with particular enrichment in pachytene spermatocytes. dsRNA formation is lower on the sex (X and Y) chromosomes. The dsRNA transcriptome is significantly less complex in juvenile mice as compared to adult controls and, possibly as a consequence, the knockout of Dicer1 has only a minor effect on the total number of transcript peaks associated with dsRNA. The comparison between dsRNA-associated genes in testis and liver with a reported set of genes that produce endogenous siRNAs reveals a significant overlap in testis but not in liver. Testis dsRNAs also significantly associate with natural antisense genes-again, this feature is not observed in liver. These findings point to a testis-specific mechanism involving natural antisense transcripts and the formation of dsRNAs that feed into the RNA interference pathway, possibly to mitigate the mutagenic impacts of recombination and transposon mobilization.

New Approach to the Surveillance of Pediatric Infectious Diseases From Ambulatory Pediatricians in the Digital Era

BACKGROUND

Many ambulatory networks in several countries have established syndromic surveillance systems to detect outbreaks of different illnesses. Here, we describe a new Pediatric and Ambulatory Research in Infectious diseases network that combined automated data extraction from the computers of primary care pediatricians.

METHODS

Pediatricians who used the same software, AxiSanté 5-Infansoft for electronic medical records were specially trained in infectious diseases, encouraged to comply with French treatments' recommendations, use of point-of-care tests and vaccination guidelines. Infectious disease diagnoses in children <16 years old in the records triggered automatic data extraction of complete records. A quality control process and external validation were developed.

RESULTS

From September 2017 to February 2020, 107 pediatricians enrolled 57,806 children (mean age 2.9 ± 2.6 years at diagnosis) with at least one infectious disease diagnosis among those followed by the network. Among the 118,193 diagnoses, the most frequent were acute otitis media (n = 44,924, 38.0%), tonsillopharyngitis (n = 13,334, 11.3%), gastroenteritis (n = 12,367, 10.5%), influenza (n = 11,062, 9.4%), bronchiolitis (n = 10,531, 8.9%), enteroviral infections (n = 8474, 7.2%) and chickenpox (n = 6857, 5.8%). A rapid diagnostic test was performed in 84.7% of cases of tonsillopharyngitis and was positive in 44%. The antibiotic recommendations from French guidelines were strictly followed: amoxicillin was the most prescribed antibiotic and less than 10% of presumed viral infections were treated.

CONCLUSIONS

This "tailor-made" network set up with quality controls and external validation represents a new approach to the surveillance of pediatric infectious diseases in the digital era and could highly optimize pediatric practices.

Impact of in-flight use of FFP2 masks on oxygen saturation: an experimental crossover study

This study was able to show in a crossover design that neither at resting conditions nor during a simulated 80 min flight wearing the examined FFP2 face mask leads to changes in the SpO2, the heart rate or the parameters of the capillary blood gas analysis.

Long-Term Bed Rest Delays the Circadian Phase of Core Body Temperature

Spaceflight can be associated with sleep loss and circadian misalignment as a result of non-24 h light-dark cycles, operational shifts in work/rest cycles, high workload under pressure, and psychological factors. Head-down tilt bed rest (HDBR) is an established model to mimic some of the physiological and psychological adaptions observed in spaceflight. Data on the effects of HDBR on circadian rhythms are scarce. To address this gap, we analyzed the change in the circadian rhythm of core body temperature (CBT) in two 60-day HDBR studies sponsored by the European Space Agency [n = 13 men, age: 31.1 ± 8.2 years (M ± SD)]. CBT was recorded for 36 h using a non-invasive and validated dual-sensor heatflux technology during the 3rd and the 8th week of HDBR. Bed rest induced a significant phase delay from the 3rd to the 8th week of HDBR (16.23 vs. 16.68 h, p = 0.005, g = 0.85) irrespective of the study site (p = 0.416, g = −0.46), corresponding to an average phase delay of about 0.9 min per day of HDBR. In conclusion, long-term bed rest weakens the entrainment of the circadian system to the 24-h day. We attribute this effect to the immobilization and reduced physical activity levels associated with HDBR. Given the critical role of diurnal rhythms for various physiological functions and behavior, our findings highlight the importance of monitoring circadian rhythms in circumstances in which gravity or physical activity levels are altered.

Endogenous Double-Stranded RNA

The birth of long non-coding RNAs (lncRNAs) is closely associated with the presence and activation of repetitive elements in the genome. The transcription of endogenous retroviruses as well as long and short interspersed elements is not only essential for evolving lncRNAs but is also a significant source of double-stranded RNA (dsRNA). From an lncRNA-centric point of view, the latter is a minor source of bother in the context of the entire cell; however, dsRNA is an essential threat. A viral infection is associated with cytoplasmic dsRNA, and endogenous RNA hybrids only differ from viral dsRNA by the 5' cap structure. Hence, a multi-layered defense network is in place to protect cells from viral infections but tolerates endogenous dsRNA structures. A first line of defense is established with compartmentalization; whereas endogenous dsRNA is found predominantly confined to the nucleus and the mitochondria, exogenous dsRNA reaches the cytoplasm. Here, various sensor proteins recognize features of dsRNA including the 5' phosphate group of viral RNAs or hybrids with a particular length but not specific nucleotide sequences. The sensors trigger cellular stress pathways and innate immunity via interferon signaling but also induce apoptosis via caspase activation. Because of its central role in viral recognition and immune activation, dsRNA sensing is implicated in autoimmune diseases and used to treat cancer.

The influence of hemodialysis-induced preload changes on the propagation speed of natural shear waves

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Research Foundation - Flanders (FWO)

Background

Shear wave elastography (SWE) is a novel ultrasound technique based on the detection of transverse waves travelling through the myocardium using high frame rate echocardiography. The propagation speed of these shear waves is dependent on the stiffness of the myocardium. Previous studies have shown the potential of SWE for the non-invasive assessment of myocardial stiffness. It is unclear, however, if preload changes lead to measurable changes in the shear wave propagation speed in the left ventricle. In patients undergoing hemodialysis, the volume status is acutely changed. In this way, the effect of preload changes on shear wave speed can be assessed.

Purpose

The aim of this study was to explore the influence of preload changes on end-diastolic shear wave propagation speed.

Methods

Until now, 6 patients (age: 80[53-85] years; female: n = 2) receiving hemodialysis treatment were included. Echocardiographic images were taken before and every hour during a 4 hour hemodialysis session. Left ventricular parasternal long-axis views were acquired with an experimental high frame rate ultrasound scanner (average frame rate: 1016[941-1310] Hz). Standard echocardiography was performed with a conventional ultrasound machine. Shear waves were visualized on tissue acceleration maps by drawing an M-mode line along the interventricular septum. Shear wave propagation speed after mitral valve closure (MVC) was calculated by measuring the slope of the wave pattern on the acceleration maps (Figure A).

Results

Over the course of hemodialysis, the systolic (141[135-156] mmHg vs. 165[105-176] mmHg; p = 0.35 among groups) and diastolic blood pressure (70[66-75] mmHg vs. 82[63-84] mmHg; p = 0.21 among groups), heart rate (56[54-73] bmp vs. 57[50-67] bpm; p = 0.76 among groups), E/A ratio (1.6[0.7-1.8] vs. 1.2[0.6-1.4]; p = 0.43 among groups) and E/e’ (14[9-15] vs. 9[8-13]; p = 0.24 among groups ) remained the same. The ultra-filtrated volumes are shown in Figure B. The shear wave propagation speed after MVC gradually decreased during hemodialysis (6.7[5.4-9.7] m/s vs. 4.4[3.6-9.0] m/s; p = 0.04 among groups) (Figure C). There was a moderate negative correlation between shear wave speed and the ultra-filtrated volume (r=-0.63; p &lt; 0.01) (Figure D).

Conclusion

The shear wave propagation speed at MVC significantly decreased over the course of hemodialysis and correlated to the ultra-filtrated volume. These results indicate that alterations in left ventricular preload affect the speed of shear waves at end-diastole. End-diastolic shear wave speed might therefore be a potential novel parameter for the evaluation of the left ventricular filling state. More patients will be included in the future to further explore these findings.

Abstract Figure.

CuSO4/[Cu(NH3)4]SO4-Composite Thermochemical Energy Storage Materials

The thermochemical energy-storage material couple CuSO₄/[Cu(NH₃)₄]SO₄ combines full reversibility, application in a medium temperature interval (<350 °C), and fast liberation of stored heat. During reaction with ammonia, a large change in the sulfate solid-state structure occurs, resulting in a 2.6-fold expansion of the bulk material due to NH₃ uptake. In order to limit this volume work, as well as enhance the thermal conductivity of the solid material, several composites of anhydrous CuSO₄ with inorganic inert support materials were prepared and characterized with regard to their energy storage density, reversibility of the storage reaction, thermal conductivity, and particle morphology. The best thermochemical energy storage properties were obtained for a 10:1 CuSO₄-sepiolite composite, combining an attractive energy storage density with slightly improved thermal conductivity and decreased bulk volume work compared to the pure salt.

Cost-effectiveness of Lutetium [177Lu] oxodotreotide versus best supportive care with octreotide in patients with midgut neuroendocrine tumors in France

BACKGROUND AND AIMS

In France, there are approximately 2,400 new cases of neuroendocrine tumors (NETs) annually. Peptide receptor radionuclide therapy with ¹⁷⁷Lu-Dotatate plus long-acting repeatable [LAR] octreotide 30 mg has been shown to significantly improve progression-free survival and overall survival relative to high-dose octreotide LAR 60 mg in patients with unresectable or metastatic progressive midgut NETs. A long-term cost-effectiveness analysis was performed to assess whether ¹⁷⁷Lu-Dotatate is a cost-effective option versus octreotide 60 mg for patients with unresectable/metastatic progressive midgut NETs from the perspective of French healthcare payer.

METHODS

The analysis was performed using a three-state partitioned survival model. In the base case analysis ¹⁷⁷Lu-Dotatate plus octreotide LAR 30 mg was compared with high-dose octreotide LAR 60 mg in patients with midgut NETs. Survival data were obtained from the phase III NETTER-1 trial in patients with metastatic midgut NETs. Future costs and clinical outcomes were discounted at 4% per annum. One-way deterministic and probabilistic sensitivity analyses were performed.

RESULTS

In the base case analysis, for patients with midgut NETs, ¹⁷⁷Lu-Dotatate treatment improved quality-adjusted life expectancy by 1.21 quality-adjusted life years (QALYs) relative to octreotide LAR 60 mg and the lifetime treatment costs were EUR 50,784 higher with ¹⁷⁷Lu-Dotatate resulting in an incremental cost-effectiveness ratio (ICER) of EUR 42,106 per QALY gained versus octreotide LAR 60 mg. When compared with everolimus, ¹⁷⁷Lu-Dotatate was associated with an ICER of EUR 59,769 per QALY gained. Sensitivity analyses showed that the results were sensitive to methods used to extrapolate survival data.

CONCLUSIONS

For patients with advanced progressive midgut NETs ¹⁷⁷Lu-Dotatate is likely to be considered a cost-effective option versus octreotide 60 mg from the perspective of the French healthcare payer.

The sense of smell is not strongly affected by ambient temperature and humidity: a prospective study in a controlled environment

INTRODUCTION

The sense of smell is dependent on environmental conditions. In this study, we analysed the effect of temperature and humidity on the ability to smell.

METHODS

Using the controlled setting of a hypobaric climate chamber 50 healthy participants (40 men, 10 women; mean age of 33 years) completed repeated testing in 4 different settings-cold/dry, cold/humid, warm/dry, warm/humid. The temperatures were 20-35 °C, respectively, and the humidity was set at 30-75%. Testing was performed using the "Sniffin' Sticks" test battery (odour threshold, discrimination and identification) in a semi-randomised order and in controlled atmospheric pressure conditions.

RESULTS

The analysis showed that neither temperature nor humidity had a significant effect on olfactory test results. This indicates that olfactory functions in healthy, young subjects with an excellent sense of smell are not strongly affected by temporary changes in environmental conditions.

Post-feeding behavior in crayfish (Procambarus clarkii): Description of an invertebrate behavioral satiety sequence

Previous studies have demonstrated that food consumption induces the behavioral satiety sequence (BSS) in some animals, a characteristic series of activities which include exploration, grooming, and resting. The BSS, while valuable in assessing the effects of drugs on food intake, has not been widely studied in non-mammalian species. Our experiment examined post-feeding behavior in crayfish using continuous recording of five behaviors: feeding, walking, grooming, leg wave, and quiescence. We found that food intake, but not sham feeding, significantly decreased feeding behavior, increased leg wave, and increased quiescence. Walking and grooming were not significantly altered by food intake. These findings indicate that post-feeding behaviors in crayfish share some characteristics with the mammalian BSS. Detailed descriptions of post-ingestive behavior in invertebrates may contribute to the development of drugs targeting feeding behaviors in medically and economically important species.

[Radium-223 for the treatment of metastatic castration-resistant prostate cancer (mCRPC) : The androgen receptor-independent active agent in the therapeutic sequence]

BACKGROUND

Radium-223 improves overall survival and preserves quality of life in patients with metastatic castration-resistant prostate cancer (mCRPC) and symptomatic bone metastases and no known visceral metastases. Radium-223 can be used in combination with a luteinizing hormone releasing hormone (LHRH) analogue and as part of a sequential treatment scheme if disease progresses after at least two prior lines of systemic mCRPC therapies or if no other available systemic treatment is eligible.

OBJECTIVES

Today physicians are faced with a previously unknown multitude and complexity of options for the treatment of mCRPC. An increasing number of clinical trials contribute to the dynamics of the therapeutic landscape. Radium-223 was approved for mCRPC treatment in 2013. Up to now the recommendations of use have been adjusted several times. Highlighting recent clinical trials and practice, this paper explores the position of radium-223 within the therapeutic sequence and outlines key elements for the interdisciplinary cooperation between uro-oncologists and nuclear medicine specialists.

RESULTS

The mode of action of radium-223 does not depend on the androgen receptor (AR) pathway. Thus, it is an option in the therapeutic sequence when the efficacy of other agents is reduced by resistance. Furthermore, the efficacy of prior or subsequent medications are neither reduced nor enhanced by radium-223. The opportunity of an AR-independent and survival-prolonging medication should be taken as soon as the indication criteria are met because the incidence of visceral metastases increases during disease progression. According to current mCRPC guidelines, the osteoprotective use of bisphosphonates or denosumab is recommended, before treatment with radium-223 is started or resumed.