Clinical Comparison of Three Indirect Pulp Capping Restorative Protocols: A Randomized Controlled Prospective Study

OBJECTIVES

The objective of this prospective double-blind clinical trial was to compare clinical outcomes of indirect pulp capping restorative protocols on permanent teeth over a 12-month period.

METHODS AND MATERIALS

Deep carious lesions in permanent teeth (90) were randomly assigned to three indirect pulp capping protocols (n=30: TheraCal LC, Dycal, and no liner). All teeth were restored with resin composite. The outcome measures were pain (VAS scale) and success rate (pulp vitality based on percussion, palpation, cold test, and radiographic findings), collected at screening, intervention, and 24-hour, 7-day, 3-month, 6-month, and 12-month follow-up visits.

RESULTS

There was no statistically significant difference in tooth sensitivity among the three indirect pulp capping protocols nor in success rates among the restorative protocols after 1 year of follow-up (p>0.1).The respective success rates, as defined by the tooth remaining vital, after 1 year were: 96.2% for TheraCal LC, 100% for Dycal, and 100% for no liner.

CONCLUSIONS

After 12-month evaluation, the success rate of indirect pulp capping therapy on permanent teeth was not affected by the pulp capping restorative protocol.

Classroom aerosol dispersion modeling: experimental assessment of a low-cost flow simulation tool

The purpose of this study was to assess the utility of a low-cost flow simulation tool for an indoor air modeling application by comparing its outputs with the results of a physical experiment, as well as those from a more advanced computational fluid dynamics (CFD) software package. Five aerosol dispersion tests were performed in two different classrooms by releasing a CO2 tracer gas from six student locations. Resultant steady-state concentrations were monitored at 13 locations around the periphery of the room. Subsequently, the experiments were modeled using both a low-cost tool (SolidWorks Flow Simulation) and a more sophisticated tool (STAR-CCM+). Models were evaluated based on their ability to predict the experimentally measured concentrations at the 13 monitoring locations by calculating four performance parameters commonly used in the evaluation of dispersion models: fractional mean bias (FB), normalized mean-square error (NMSE), fraction of predicted value within a factor of two (FAC2), and normalized absolute difference (NAD). The more sophisticated model performed better in 15 of the 20 possible cases (five tests at four parameters each), with parameters meeting acceptance criteria in 19 of 20 cases. However, the lower-cost tool was only slightly worse, with parameters meeting acceptance criteria in 18 of 20 cases, and it performed better than the other tool in 3 of 20 cases. Because it provides useful results at a fraction of the monetary and training cost and is already widely accessible to many institutions, such a tool may be worthwhile for many indoor aerosol dispersion applications, especially for students or researchers just beginning CFD modeling.

Targeted temperature management and PbtO2 in traumatic brain injury

Introduction

Targeted Temperature Management (TTM) to normothermia is widely used in traumatic brain injury (TBI). We investigated the effects to of TTM to normothermia patients with TBI (GCS≤12) monitored with multimodality monitoring, to better understand the physiological consequences of this intervention.

Research question

In TBI patients cooled to normothermia and in which brain oxygenation deteriorates, are there changes in physiological parameters which are pertinent to brain oxygenation?

Material and method

102 TBI patients with continuous recordings of intracranial pressure (ICP) and brain oxygen tension (PbtO2) were studied retrospectively. Non-continuous arterial carbon dioxide (PaCO2) and oxygen (PaO2) tensions, and core body temperature (Tc) were added. PaO2 and PaCO2 were also corrected for Tc. Transitions from elevated Tc to normothermia were identified in 39 patients. The 8 h pre and post the transition to normothermia were compared. Data is given as median [IQR] or mean (SD).

Results

Overall, normothermia reduced ICP (12 [9-18] -11 [8-17] mmHg, p < 0.009) and Tcore (38.3 [0.3]-36.9 [0.4] oC, p < 0.001), but not PbtO2 (23.3 [16.6]-24.4 [17.2-28.7] mmHg, NS). Normothermia was associated with a fall in PbtO2 in 18 patients (24.5 [9.3] -20.8 [7.6] mmHg). Only in those with a fall in PbtO2 with cooling did ICP (15 [10.8-18.5] -12 [7.8-17.3] mmHg, p = 0.002), and temperature corrected PaCO2 (5.3 [0.5]- 4.9 [0.8] kPa, p = 0.001) decrease.

Discussion and conclusion

A reduction in PbtO2 was only present in the subgroup of patients with a fall in temperature corrected PaCO2 with cooling. This suggests that even modest temperature changes could result in occult hyperventilation in some patients. pH stat correction of ventilation may be an important factor to consider in future TTM protocols.

Surgically Targeted Radiation Therapy (STaRT) for Brain Metastases: Initial Experience from a Prospective Multi-Institutional Registry

PURPOSE/OBJECTIVE(S)

Resection and intraoperative brachytherapy for patients with large, operable brain metastasis allows for both relief of mass effect and the delivery of radiotherapy (RT) to the resection cavity with a favorable dosimetric profile. The objective of this study was to analyze early patterns-of-care and treatment-related toxicity outcomes for brain metastasis patients treated with surgically targeted radiation therapy (STaRT) using a novel brachytherapy carrier.

MATERIALS/METHODS

Patients with brain metastasis, de novo and recurrent disease, who enrolled onto a prospective multi-institutional observational study (NCT04427384) were the subject of this analysis. Patients underwent resection and immediate implantation of bioresorbable, conformable, 20 mm x 20 mm x 4 mm collagen tile brachytherapy device(s) containing four uniform-intensity Cesium-131 sources. Toxicities were categorized using the CTCAE v5.0 adverse event (AE) criteria.

RESULTS

From 10/2020 to 01/2023, 13 participating sites enrolled and treated 48 patients with 51 metastases (13 with de novo and 35 patients with recurrent brain metastases), and 3 patients had 2 lesions implanted at the same procedure. Median age was 61 years (range: 28-80), 52% were female, and the most common primary types were lung (56%) and breast (13%). The median maximum pre-operative dimension was 3.4 cm (range: 1.7-5.7) and median pre-operative tumor volume 13.7cm3 (range: 1.7-132). 64% had received prior RT with a median time from last RT to STaRT of 14.6 months range: 3.5-57.3). Median KPS at screening was 80 (range: 50-100), and remained stable at post op visit (80, range: 50-100), and at 3-months following treatment (80, range 50-100), respectively (p>0.05). The median time for implantation was 3 minutes (range: 0.4-30). At a median follow-up of 4 months (range: <1-18), no patient experienced a radiation-attributed AE, and only 1 attributable Gr >3 AE was noted (Gr 5 intracerebral hemorrhage deemed probably related to surgery and unrelated to the implanted device).

CONCLUSION

Early results from this prospective multi-center trial demonstrate the feasibility and safety of STaRT. The lack of radiation-related AE, even with short follow-up, is intriguing given the relatively large lesion size and proportion of patients treated for recurrent, previously irradiated disease. Additional follow-up will provide data on tumor control outcomes and radiation necrosis rates using this novel technique.

Implementing Standardized Patient Education in Radiation Oncology

PURPOSE/OBJECTIVE(S)

Patient education empowers patients, improving their health status during and after cancer treatment (Howell et al., 2017). We hypothesize that standardizing healthcare provider delivery of educational materials (HPE) using an electronic medical record (EMR) will increase delivery to patients (pts).

MATERIALS/METHODS

During the study period (9/2020 - 11/2022) 13,650 pts in a multi-centered single health system (HS) received HPE and were analyzed in a retrospective convenience sample frame. There were 16,769 education touchpoints from Radiation Oncology departments (RO) and 8,269 from Medical Oncology (MO) departments. Provision of HPE was standardized in RO during this era. Relationship of ethnicity, age, and sex/gender to receipt of HPE at single vs multiple time points across the HS was examined using association analysis.

RESULTS

Within the combined sample taken from RO and MO departments in the HS the mean pt age was 64y (7 - >90); 71% of pts identified as white, 95.7% non-Hispanic, and 55% female. Across ethnicity, age, and sex/gender, increased HPE was provided in RO vs MO departments (p < 0.001). Distribution of HPE in RO was equal between male and female pts (73%), while distribution to female pts was higher than male in MO. (60% vs 57%, p < 0.001). Receipt of HPE at more than one time point was increased in RO across cancer types (Table 1). In RO, 73% of patients received education at more than one time point, compared to 58.7% in other departments (p < 0.001). Receipt of HPE at more than one time point was increased in RO for patients identifying as American Indian or Alaska Native (84% vs 0, p = 0.001, n = 28), Asian (73.4% vs 56%, p < 0.001, n = 824), and Black (75% vs 60%, p < 0.001, n = 4005). HPE was received at more than one time point in RO in 75.7% of patients age 7-39, 76.4% 40-64, 71.2% 65-79, and 67.6% in those 80 and above, compared to 62.0%, 63.2%, 56.3%, and 49.2%, respectively in MO departments (p = <0.01).

CONCLUSION

Standardization of HPE within RO increased delivery to patients across gender, race/ethnicity, age, and cancer diagnosis, particularly regarding number of educational touchpoints for patients in underserved populations based on race and age. Our results suggest that widespread standardization of HPE is likely to improve distribution of education to all patient groups and should be systematically supported.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Usability, accuracy, and cost-effectiveness of a medical software for early pregnancies: a retrospective study

STUDY QUESTION

Can early pregnancies be accurately and cost-effectively diagnosed and managed using a new medical computerized tool?

SUMMARY ANSWER

Compared to the standard clinical approach, retrospective implementation of the new medical software in a gynaecological emergency unit was correlated with more accurate diagnosis and more cost-effective management.

WHAT IS KNOWN ALREADY

Early pregnancy complications are responsible for a large percentage of consultations, mostly in emergency units, with guidelines becoming complex and poorly known/misunderstood by practitioners.

STUDY DESIGN, SIZE, DURATION

A total of 780 gynaecological emergency consultations (446 patients), recorded between November 2018 and June 2019 in a tertiary university hospital, were retrospectively encoded in a new medical computerized tool. The inclusion criteria were a positive hCG test result, ultrasonographical visualization of gestational sac, and/or embryo corresponding to a gestational age of 14 weeks or less. Diagnosis and management suggested by the new computerized tool are named eDiagnoses, while those provided by a gynaecologist member of the emergency department staff are called medDiagnoses.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Usability was the primary endpoint, with accuracy and cost reduction, respectively, as secondary and tertiary endpoints. Identical eDiagnoses/medDiagnoses were considered as accurate. During follow-up visits, if the updated eDiagnoses and medDiagnoses became both identical to a previously discrepant eDiagnosis or medDiagnosis, this previous eDiagnosis or medDiagnosis was also considered as correct. Four double-blinded experts reviewed persistent discrepancies, determining the accurate diagnoses. eDiagnoses/medDiagnoses accuracies were compared using McNemar's Chi square test, sensitivity, specificity, and predictive values.

MAIN RESULTS AND THE ROLE OF CHANCE

Only 1 (0.1%) from 780 registered medical records lacked data for full encoding. Out of the 779 remaining consultations, 675 eDiagnoses were identical to the medDiagnoses (86.6%) and 104 were discrepant (13.4%). From these 104, 60 reached an agreement during follow-up consultations, with 59 medDiagnoses ultimately changing into the initial eDiagnoses (98%) and only one discrepant eDiagnosis turning later into the initial medDiagnosis (2%). Finally, 24 remained discrepant at all subsequent checks and 20 were not re-evaluated. Out of these 44, the majority of experts agreed on 38 eDiagnoses (86%) and 5 medDiagnoses (11%, including four twin pregnancies whose twinness was the only discrepancy). No majority was reached for one discrepant eDiagnosis/medDiagnosis (2%). In total, the accuracy of eDiagnoses was 99.1% (675 + 59 + 38 = 772 eDiagnoses out of 779), versus 87.4% (675 + 1 + 5 = 681) for medDiagnoses (P < 0.0001). Calculating all basic costs of extra consultations, extra-medications, extra-surgeries, and extra-hospitalizations induced by incorrect medDiagnoses versus eDiagnoses, the new medical computerized tool would have saved 3623.75 Euros per month. Retrospectively, the medical computerized tool was usable in almost all the recorded cases (99.9%), globally more accurate (99.1% versus 87.4%), and for all diagnoses except twinning reports, and it was more cost-effective than the standard clinical approach.

LIMITATIONS, REASONS FOR CAUTION

The retrospective study design is a limitation. Some observed improvements with the medical software could derive from the encoding by a rested and/or more experienced physician who had a better ultrasound interpretation. This software cannot replace clinical and ultrasonographical skills but may improve the compliance to published guidelines.

WIDER IMPLICATIONS OF THE FINDINGS

This medical computerized tool is improving. A new version considers diagnosis and management of multiple pregnancies with their specificities (potentially multiple locations, chorioamnionicity). Prospective evaluations will be required. Further developmental steps are planned, including software incorporation into ultrasound devices and integration of previously published predictive/prognostic factors (e.g. serum progesterone, corpus luteum scoring).

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was obtained for this study. F.B. and D.G. created the new medical software.

TRIAL REGISTRATION NUMBER

NCT03993015.

Eukaryotic-like gephyrin and cognate membrane receptor coordinate corynebacterial cell division and polar elongation

The order Corynebacteriales includes major industrial and pathogenic actinobacteria such as Corynebacterium glutamicum or Mycobacterium tuberculosis . Their elaborate multi-layered cell wall, composed primarily of the mycolyl-arabinogalactan-peptidoglycan complex, and their polar growth mode impose a stringent coordination between the septal divisome, organized around the tubulin-like protein FtsZ, and the polar elongasome, assembled around the tropomyosin-like protein Wag31. Here, we report the identification of two new divisome members, a gephyrin-like repurposed molybdotransferase (GLP) and its membrane receptor (GLPR). We show that the interplay between the GLPR/GLP module, FtsZ and Wag31 is crucial for orchestrating cell cycle progression. Our results provide a detailed molecular understanding of the crosstalk between two essential machineries, the divisome and elongasome, and reveal that Corynebacteriales have evolved a protein scaffold to control cell division and morphogenesis similar to the gephyrin/GlyR system that in higher eukaryotes mediates synaptic signaling through network organization of membrane receptors and the microtubule cytoskeleton.

Attitudes of Newly Hired Medicine Faculty Regarding Mentorship and Developmental Networks

Prior research shows that most Schools of Medicine faculty consider mentorship the most crucial factor in faculty development and retention. Many faculty are establishing developmental networks in lieu of hierarchical dyadic mentoring relationships. Clinicians are less likely than other newly hired faculty groups to seek mentorship despite having assigned mentors. The study's purpose was to determine the attitudes of newly hired faculty at the University of New Mexico School of Medicine (UNM SOM) regarding mentorship and developmental networks. Within their first year of hire, all newly hired faculty at UNM SOM are required to participate in a two-day orientation to the institution event called 'Quikstart.' During seven such events, new faculty [N=131] were surveyed anonymously on six single-response questions about their attitudes regarding mentorship and developmental networks, administered via online polls between September 2018 and July 2022. In this descriptive study, summary characteristics were analyzed. Newly hired faculty mentees reported that creating a developmental network was hampered by difficulties finding multiple mentors (55.3%), receiving conflicting advice from multiple mentors (22.4%), and gathering many mentors at the same location at the same time (11.8% ). Lack of clarity regarding faculty mentee needs (55.5%), mentors' unavailability (17.6%), and failure to find mentors (14.3%) were the most often mentioned difficulties during the initiation stage of mentorship (Hitchcock et al., 1995). Although the literature advocates moving from hierarchical dyadic mentoring relationships to developmental networks, this transition for Medicine faculty mentees will likely be hindered by a shortage of adequately trained mentors. Institutions need to identify and train mentors, incentivize and support mentorship, and encourage the creation and maintenance of self-selected development networks, possibly under the leadership of a transitional mentor.

Eurasiaplex-2: Shifting the focus to SNPs with high population specificity increases the power of forensic ancestry marker sets

To compile a new South Asian-informative panel of forensic ancestry SNPs, we changed the strategy for selecting the most powerful markers for this purpose by targeting polymorphisms with near absolute specificity - when the South Asian-informative allele identified is absent from all other populations or present at frequencies below 0.001 (one in a thousand). More than 120 candidate SNPs were identified from 1000 Genomes datasets satisfying an allele frequency screen of ≥ 0.1 (10 % or more) allele frequency in South Asians, and ≤ 0.001 (0.1 % or less) in African, East Asian, and European populations. From the candidate pool of markers, a final panel of 36 SNPs, widely distributed across most autosomes, were selected that had allele frequencies in the five 1000 Genomes South Asian populations ranging from 0.4 to 0.15. Slightly lower average allele frequencies, but consistent patterns of informativeness were observed in gnomAD South Asian datasets used to validate the 1000 Genomes variant annotations. We named the panel of 36 South Asian-specific SNPs Eurasiaplex-2, and the informativeness of the panel was evaluated by compiling worldwide population data from 4097 samples in four genome variation databases that largely complement the global sampling of 1000 Genomes. Consistent patterns of allele frequency distribution, which were specific to South Asia, were observed in all populations in, or closely sited to, the Indian sub-continent. Pakistani populations from the HGDP-CEPH panel had markedly lower allele frequencies, highlighting the need to develop a statistical system to evaluate the ancestry inference value of counting the number of population-specific alleles present in an individual.

Nurse and general practioner-led up-titration strategy: a real world experience in a heart failure unit in colombia

Funding Acknowledgements

Type of funding sources: None.

Background

Despite improvement of heart failure (HF) prescription rates, doses prescribed in clinical practice are lower than those achieved in randomized clinical trials. Nurse-led up-titration strategy has been widely used in Europe with promising results. Nevertheless, there is no evidence of this approach in Latin America.

Methods

A prospective cohort study was conducted in 50 patients with reduced ejection fraction to evaluate efficacy and safety of nurse and general practioner(GP)-led up-titration protocol, based on problem solving from the European Society of Cardiology HF guidelines. Patients were admitted in our HF unit from January 2017 to December 2019. After discharge our clinical pathway provides 3 types of visits : Cardiologist visits, educational visits and titration visits with GP and registered nurse. Along intervention the registered nurse lead flexible diuretic titration and structured phone monitoring calls.

Results

Baseline characteristics are showed in Table 1. Mean age was 72.5 years, 50% of patients were women, 66% had ischemic cardiomiopathy, mean N-terminal pro-B-type natiuretic peptide was 3285pg/dl, and 58% of patients were NYHA class III. At 97 days with an average of 4 up-titration visits disease-modifying drugs titration was completed. At the beginning 98% of patients had Beta Blockers (BB) , 98% had Mineralocorticoid Receptor Antagonist (MRA), and all of them had Angiotensin Converting Enzyme Inhibitors, angiotensin receptor blockers or Angiotensin Receptor Neprilysin Inhibitor (ARNI). According to the guidelines Angiotensin Converting Enzyme Inhibitors and angiotensin receptor blockers were replaced by ARNI in symptomatic patients. At the end of titration, BB target dose was achieved for 44% of patients, intermediate dose for 46% and final low dose for only 10% of patients. Ivabradine was added for 22% of patients. MRA intermediate and high doses were achieved for 82,5% of patients. Target dose of ARNI was achieved for 62% of patients, intermediate dose for 22% and only 20% of patients remained in starting dose. On average ARNI target dose was completed at 56 days. According to our protocol three patients stopped MRA due to hyperkalemia and symptomatic hypotension was the main cause for stopping up-titration. There was a relationship between patient´s caregiver and higher doses of ARNI( p=0.624) and BB (p=0.421).

Conclusion

A nurse and GP directed up-titration protocol is an encouraging strategy in HF units to achieve the recommended doses of disease-modifying drugs according to the guidelines.

P-404 Usability, accuracy and cost-effectiveness of “eDiagEPU”, a medical software for early pregnancies: a retrospective study

Study question

Can early pregnancies be accurately and cost-effectively diagnosed and managed using a new medical computerised tool, named “eDiagEPU”?

Summary answer

Compared to the standard clinical approach, the retrospective implementation of “eDiagEPU” in a gynaecological emergency unit was correlated with sharper diagnoses and more cost-effective managements.

What is known already

Early pregnancies complications are responsible for a large percentage of consultations, mostly in emergency units. Moreover, clinical guidelines updates for the management of Intrauterine Pregnancies of Uncertain Viability (IPUV) have become increasingly complex and seem to be unknown or misunderstood by several practitioners. Specifically, a recently published prospective multinational survey revealed a limited knowledge regarding early pregnancy guidelines, with 69.0% of the participants reporting incorrect managements of IPUV and 86.6% misinterpreting the evolution of serum human chorionic gonadotropin (hCG).

In an attempt to aid practitioners with the diagnosis and management of early pregnancies, a software, named “eDiagEPU”, was developed.

Study design, size, duration

A total of 780 consultations, recorded between November 2018 and June 2019 in the gynaecological emergency unit of a tertiary university hospital, were retrospectively encoded in eDiagEPU. Positive hCG, ultrasonographical visualisation of gestational sac or/and embryo corresponding to a gestational age of 14 weeks gestation or less were the inclusion criteria.

Diagnoses and managements suggested by eDiagEPU are named “eDiagnoses”. The ones provided by a gynaecologist member of the emergency department staff are called “medDiagnoses”.

Participants/materials, setting, methods

Identical eDiagnosis and medDiagnosis were considered as correct (gold standard). During follow-up examinations, if they became both identical to a previous discrepant eDiagnosis or medDiagnosis, this previous eDiagnosis/medDiagnosis was considered as correct. Persistent discrepancies were reviewed by four double-blinded experts whose majority defined the correct eDiagnosis/medDiagnosis.

The accuracies of eDiagnoses/medDiagnoses were compared using McNemar’s Chi square test, computing diagnostic values (Sensitivity, Specificity, and predictive values) and 95% Confidence Intervals (CI). Cost reduction was also analysed.

Main results and the role of chance

Only one datum (0.1%) from 780 registered medical records was missing to process using “eDiagEPU”. Out of the 779 consultations that could be fully encoded until obtaining an eDiagnosis, 675 eDiagnoses were identical to the medDiagnoses (86.6%) and 104 discrepant (13.4%). From these 104, 60 reached an agreement during follow-up controls with 59 medDiagnoses finally changing into the initial eDiagnoses (98%) while only one discrepant eDiagnosis turning later into the initial medDiagnosis (2%). Finally, 24 remained discrepant at all subsequent checks and 20 were not reevaluated. Out of these 44 discrepancies without identical diagnoses/managements during follow-up controls, the double-blinded experts majority chose 38 eDiagnoses (86%) and 5 medDiagnoses (11%) including 4 twin pregnancies whose twinness was the only discrepancy. One discrepant eDiagnosis/medDiagnosis reached no majority (2%).

In total, eDiagnoses accuracy was 99.1% (675 + 59 + 38=772 eDiagnoses out of 779 final diagnoses), vs 87.4% (675 + 1 + 5=681) for medDiagnoses accuracy (p &lt; 0.0001). Calculating all basic costs of consultations, medications, surgeries and hospitalisations induced by medDiagnoses versus eDiagnoses, “eDiagEPU” would have saved 3 623.75 € per month.

Retrospectively, “eDiaEPU” was usable (99.9%), more accurate for each diagnosis except twinning report and more cost-effective than standard clinical approach.

Limitations, reasons for caution

The retrospective design is a limitation, as well as the quality of ultrasound interpretation. Some improvements could not derive exclusively from “eDiagEPU” but also from the encoding by a rested or more experienced physician. This software cannot replace clinical and ultrasonographical skills but can improve the diagnostic and therapeutic reasoning.

Wider implications of the findings

An improved “eDiagEPU” version, considering the diagnosis and management of multiple pregnancies with their specificities (potentially multiple locations, chorioamnionicity) has been developed. Prospective evaluations will be required. Further development steps are considered, including software incorporation into ultrasound devices and integration of previously published predictive/prognostic factors (serum progesterone, corpus luteum scoring...).

Trial registration number

NCT03993015

P-211 Significant differences in efficiency between two commonly used ionophore solutions for assisted oocyte activation (AOA): a prospective comparison of ionomycin and A23187

Study question

Are there differences in oocyte activation rate and developmental morphokinetic after assisted oocyte activation (AOA) with either ionomycin or A23187?

Summary answer

Ionomycin produces greater oocyte activation rate than A23187 (43.1% vs 15.9%), while the morphokinetic pattern of parthenotes’ development is similar between both Ca2+ ionophores.

What is known already

Fertilization failure (FF) after ICSI is often due to a male factor, such as the alteration of sperm-borne oocyte activating factors or globozoospermia. AOA can restore fertilization rate by stimulating transient spikes of Ca2+ in the cytoplasm of the oocyte, but its efficiency and effect on embryo development are not fully characterized. Here, the efficiency of two AOA preparation and protocols commonly used in clinical practice is compared using parthenogenetically activated human oocytes. The objective is to identify the most appropriate protocol for AOA and to compare the morphokinetic pattern of the generated parthenotes up to expanded blastocyst (tB).

Study design, size, duration

Prospective study involving 120 human oocytes from 66 women from March 2019 to November 2021. Oocytes were activated with two AOA protocols after mock ICSI: i) A23187 (ready-to-use solution, GM508 CultActive (Gynemed) n = 69), and ii) Ionomycin (homemade solution, 10 µmol/L, n = 51). Oocyte activation and development were analyzed in both groups; further, the morphokinetic patterns were compared; videos of embryos obtained with donor oocytes and sperm (n = 39) were used as comparator of normal developmental kinetics.

Participants/materials, setting, methods

Oocytes were injected with latex microspheres to simulate ICSI, followed by AOA. A23187 was used according to manufacturer specification. For ionomycin, three incubations of seven minutes each were performed. Resulting parthenotes (1PN) were incubated in a time-lapse system for 160h. Activation and developmental rates, tPNf (pronucleus fading), t2, t3, t4, t5, t8 (from 1st division to 8-cell), tsB (blastulation onset) and tB (blastocyst expansion) were compared using Student’s T-test and ANOVA. Statistical significance: p-value &lt;0.05.

Main results and the role of chance

Ionomycin resulted in a significantly higher oocyte activation rate (22/51, 43.1%) than A23187 (11/69, 15.9%), p = 0.0009. In the ionomycin group, 81.8% (18/22) of parthenotes reached the 2-cell stage, 45.5% (10/22) reached the 5-cell stage, and 18.2% (4/22) reached the pseudo-blastocyst stage, as expected for these pseudo-embryos lacking the contribution of the sperm. In the A23187 group, 54.5% (6/11) reached the 2-cell stage, 27.3% (3/11) the 5-cell stage, and none formed pseudo-blastocysts. While the number of parthenotes progressing through development is much lower for A23187, the expected poor development of human parthenotes past activation and corresponding low numbers did not allow to reach statistical significance (p &gt; 0.05). tPNf was significantly different among the 3 groups compared: 47.4±37.5h (n = 11, A23187), 27.7±23.8h (n = 21, ionomycin) and 23.3±4.6h (n = 39, control), p = 0.0019; with ionomycin presenting an average tPNf similar to the one obtained by ICSI. Among activated oocytes, the morphokinetic pattern in the ionomycin and A23187 groups was very similar to the one obtained in the control group (p &gt; 0.05 at all timings). As an example, the t5 in the 3 groups was 58.5±12.6h (n = 3, A23187), 45.6±21.8h (n = 10, ionomycin), and 49.5±12.4h (n = 34, control), p = 0.29.

Limitations, reasons for caution

The low number of parthenotes progressing past 2-cells limit the possibility to extract solid conclusions regarding the morphokinetic patterns after AOA. The efficiency of activation using the two tested protocol is however confirmed.

Wider implications of the findings

The use of homemade ionomycin solutions is an effective option for the treatment of fertilization failures where assisted oocyte activation is indicated. Caution should be exerted when using GM508 Cultactive to investigate fertilization failures of oocyte origin.

Trial registration number

not applicable

Phonemic fluency in post-ICU patients after severe COVID-19 infection: The role of cognitive reserve

Introduction

Cognitive function may be impaired in COVID-19 patients, especially in executive functions such as phonemic fluency. Among risk factors, inflammation during hospitalization is related with worse cognitive performance in the long term. On the other side, it has been shown that cognitive reserve (CR) protects against cognitive impairment associated with brain damage, psychiatric disorders and neurodegenerative diseases.

Objectives

Our aim is to study the protective role of cognitive reserve in phonemic fluency to inflammation after SARS-CoV-2 infection.

Methods

We enrolled a cohort of 102 severe SARS-CoV-2 survivors after Intensive Care Unit (ICU) discharge and 58 agreed to participate in this 6-month follow-up study. Patients with previously known cognitive impairment were excluded. Demographic, clinical and laboratory data were collected. To assess the phonemic fluency, we used the Controlled Oral Word Association Test (COWAT) controlling the effects of age and education. Inflammation was recorded according to the number of days with high CRP. ANCOVA analyses were used to test the effect of interaction between medical variables and cognitive reserve on phonemic fluency.

Results

The COVID-19 inflammation interacted with CR in phonemic fluency (F= 6.47, p= 0.01), with worse performance in patients with low CR (mean 16.7 (10.2-23.3)) than those with high CR (mean 37.7 (34.3-41.2)) in function of number of days with high PCR during ICU stay.

Conclusions

The role of the cognitive reserve is important to reduce the cognitive impairment related with COVID-19 inflammation in post-ICU patients.

Disclosure

No significant relationships.

Repeat cryoablation as a redo procedure for atrial fibrillation ablation: Is it a good choice?

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Medtronic Inc.

Introduction

Catheter ablation of atrial fibrillation, both cryoablation and radiofrequency pulmonary vein isolation, have demonstrated to be safe and effective techniques for treating symptomatic atrial fibrillation as a first procedure. However, about one in three patients may face a redo procedure due to AF recurrence. The most suitable technique for redo is unknown.

Purpose

The aim of this study is to assess the efficacy of cryoballoon AF ablation as a redo technique in patients with prior cryoballoon or radiofrequency AF ablation.

Methods

We analyzed a nation-wide real-world cryoablation registry (RECABA) and compared patients who were referred for a first cryoballoon AF ablation procedure with those who had previously undergone cryoballoon or radiofrequency pulmonary vein isolation. The primary endpoint was AF recurrence during the first year after a 3-month blanking period. We performed survival analysis and built univariate and multivariate cox regression models.

Results

From 1742 patients, 1625 had a 12-month follow-up visit. 1551 (95.45%) underwent a first cryoballoon ablation, whereas 33 (2.03%) had a previous CB ablation performed and 41 (2.52%) a previous RF ablation.

Mean age was 58.6 ±10.4 years and 511 (31.5%) were women. 463 (28.5%) had persistent atrial fibrillation and there were no major clinical differences between groups.

Prior-CB group had a higher share of veins without electrogram visualization, with a median of 100% (IQR 75%-100%), compared to prior-RF group (median 67%, IQR 25%-75%) and first procedure group (median 25%, IQR 0%-50%). Kruskal-Wallis test Chi2=54.35, p&lt;0.0001.

12-month Kaplan–Meier estimate of freedom from AF recurrence after the blanking period was 78.5% (95% CI 76.2% - 80.7%) in the first procedure group, 61.0% (95% CI 41.4% - 75.8%) in the prior-CB and 89.2% (95% CI 73.6% - 95.9%) in the prior-RF group. Log-rank test Chi2=17.49, p&lt;0.0001.

Multivariate cox regression analysis pointed female sex, persistent AF, and prior-CB ablation as independent predictors of AF recurrence. The adjusted HR for AF recurrence of prior-CB ablation vs first-CB ablation was 3.13 (95% CI 1.82 -5.40) and for prior-RF vs first CB-ablation was 1.01 (95% CI 0.51 – 1.97).

Conclusion

Repeat cryoballoon AF ablation shows higher rates of AF recurrences compared to first CB procedures or after prior RF ablation. These data suggest that patients with AF recurrence after CB-ablation have worse arrhythmic outcomes and may benefit from other ablation techniques after a recurrence.

SELNET clinical practice guidelines for bone sarcoma

Bone sarcoma are infrequent diseases, representing < 0.2% of all adult neoplasms. A multidisciplinary management within reference centers for sarcoma, with discussion of the diagnostic and therapeutic strategies within an expert multidisciplinary tumour board, is essential for these patients, given its heterogeneity and low frequency. This approach leads to an improvement in patient's outcome, as demonstrated in several studies. The Sarcoma European Latin-American Network (SELNET), aims to improve clinical outcome in sarcoma care, with a special focus in Latin-American countries. These Clinical Practice Guidelines (CPG) have been developed and agreed by a multidisciplinary expert group (including medical and radiation oncologist, surgical oncologist, orthopaedic surgeons, radiologist, pathologist, molecular biologist and representatives of patients advocacy groups) of the SELNET consortium, and are conceived to provide the standard approach to diagnosis, treatment and follow-up of bone sarcoma patients in the Latin-American context.

Resolvin D2 promotes host defense in a 2 - hit model of sepsis with secondary lung infection

In the development of sepsis, there is early, massive inflammation which can lead to multiple organ failure. Later there is an immunosuppressed phase where the host is susceptible to secondary infections or is unable to clear existing infection. Specialized Pro-resolving Mediators (SPMs) are endogenously produced lipids which resolve infection by decreasing bacteria load and reducing systemic inflammatory response. There has been little work studying if SPMs given late, can promote host defense. We examined if an SPM, Resolvin D2 (RvD2) could promote host defense in a 2-hit mouse model of cecal ligation and puncture (CLP) sepsis and secondary Pseudomonas aeruginosa lung infection. RvD2 given 48 h after mild CLP (1st hit), increased gene expression of Toll-like receptor-2 (TLR-2) and alveolar macrophage/monocyte phagocytic ability compared to CLP mice given saline vehicle. In this model, RvD2 did not affect plasma IL-6 or IL-10. These effects induced by RvD2, lowered lung bacterial load and decreased mortality after the secondary infection of Pseudomonas aeruginosa (2nd hit). Splenic T-cell numbers were also increased in RvD2 treated mice compared to saline vehicle treated animals. The results suggest that RvD2 promoted mechanisms of host defense in a 2-hit model sepsis and secondary lung infection.

A Comprehensive, FAIR File Format for Neuroanatomical Structure Modeling

With advances in microscopy and computer science, the technique of digitally reconstructing, modeling, and quantifying microscopic anatomies has become central to many fields of biological research. MBF Bioscience has chosen to openly document their digital reconstruction file format, the Neuromorphological File Specification, available at www.mbfbioscience.com/filespecification (Angstman et al., 2020). The format, created and maintained by MBF Bioscience, is broadly utilized by the neuroscience community. The data format's structure and capabilities have evolved since its inception, with modifications made to keep pace with advancements in microscopy and the scientific questions raised by worldwide experts in the field. More recent modifications to the neuromorphological file format ensure it abides by the Findable, Accessible, Interoperable, and Reusable (FAIR) data principles promoted by the International Neuroinformatics Coordinating Facility (INCF; Wilkinson et al., Scientific Data, 3, 160018,, 2016). The incorporated metadata make it easy to identify and repurpose these data types for downstream applications and investigation. This publication describes key elements of the file format and details their relevant structural advantages in an effort to encourage the reuse of these rich data files for alternative analysis or reproduction of derived conclusions.

UV/Vis absorption spectroelectrochemistry of folic acid

UV/Vis absorption spectroelectrochemistry is a very promising analytical technique due to the complementary information that is simultaneously obtained from electrochemistry and spectroscopy. In this work, this technique is used in a parallel configuration to study the oxidation of folic acid in alkaline medium. Herein, UV/Vis absorption spectroelectrochemistry has been used to detect both the oxidation products and the folic acid consumed at the electrode/solution interface, allowing us to develop an analytical protocol to quantify vitamin B9 in pharmaceutical tablets. Linear ranges of three orders of magnitude have been achieved in basic medium (pH = 12.9), obtaining high repeatability and low detection limits. The spectroelectrochemical determination of folic acid in pharmaceutical tablets at alkaline pH values is particularly interesting because of the changes that occur in the optical signal during the electrochemical oxidation of FA, providing results with very good figures of merit and demonstrating the utility and versatility of this hyphenated technique, UV/Vis absorption spectroelectrochemistry.

Clinical risk factors for early mortality in patients with community-acquired septic shock. The importance of adequate source control

OBJECTIVE

To evaluate the incidence and risk factors for early mortality (EM) in the ICU in patients with community-acquired septic shock (CASS).

DESIGN

A retrospective cohort study of patients with CASS admitted to the ICU (2003-2016).

SETTING

ICU at a University Hospital in Spain.

PATIENTS

All consecutive patients admitted to the ICU with CASS.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

CASS was defined according to the Sepsis-3 definitions. EM were defined as occurring within of 72h following ICU admission. A multinomial logistic regression analysis was performed to identify the risk factors associated with early deaths.

RESULTS

During the study period, 625 patients met the Sepsis-3 criteria and admitted with CASS. 14.4% of all patients died within the first 72h. Of 161 patients who died in the ICU, 90 (55.9%) died within the first 72h. The percentage of early and late mortality did not vary significantly during the study period. The need and adequacy of source control were significantly lower in patients with EM. In the multivariate analysis, ARDS, non-respiratory infections, bacteremia and severity at admission were variables independently associated with EM. The only factor that decreased EM was adequate source control in patients with infections amenable to source control.

CONCLUSIONS

The incidence of EM has remained stable over time, which means that more than half of the patients who die from CASS do so within the first 72h. Infections where adequate source control can be performed have lower EM.

Co-designing a training package to promote health/oral health for people experiencing homelessness

Background

In Scotland, 31,333 households were assessed as experiencing homelessness in 2019/20. This population present high morbidity and mortality which is a public health issue. Their health needs have been identified within Scottish policy as part of the broad goal of reducing inequalities and poverty. Those experiencing homelessness face multiple exclusions that must be addressed by practitioners from all health and social care sectors. Frontline staff have identified they often do not have adequate information and/or training on wider health issues linked with their client's needs. The aim of this research is to co-produce training resources to support front-line staff to discuss and to promote health and oral health.

Methods

Community-based participatory research that used online workshops to listen to the views of people with lived experience, practitioners and students from health and third sector, and policy makers regarding accessibility of services and practitioner approach towards those experiencing homelessness. Content analysis will be used to identified recurrent themes.

Results

The preliminary findings shown that lack of empathy from practitioners, continuity of care and stigma are barriers to access services. This is informing a co-designed knowledge exchange training packaged to help practitioners to improve knowledge and ability to promote health/oral health and to engage with people experiencing homelessness or at risk of becoming homeless. Educational materials (e-book on health promotion, comics books on barriers to access services, and a guide to promote oral health) compose this training package.

Conclusions

The training package allows adaptations to different settings and contexts and will be an important resource to be used by practitioners from different fields to prevent and tackle homelessness. Participants are sharing important views related to the need of a human rights and social justice-based approach to health promotion.

Key messages

Development of a co-designed knowledge exchange training package to improve practitioners' knowledge and ability to communicate and to engage with people experiencing homelessness. To empower people experiencing homelessness regarding positive health/oral health behavior change.

Healthcare needs of young people transitioning back to the community after a custodial sentence

Background

People in prison have poorer health outcomes than the general population, added by the long-term impact of incarceration on mortality. Young people in custody face extra challenges associated with the stage of development. There is a lack of a tailored approach and policy to young people when transitioning back to the community. This paper draws from a PhD research that looked at the challenges to access healthcare during the transition back to the community. The specific question is: What are young people's healthcare needs when released from custodial sentences?

Methods

An ethnographic study conducted in Scotland in partnership with a community-based organisation. The participants were eight young people and ten practitioners that work in health and social care. Participatory observation and in-depth interviews were used to collect data during July 2019 and March 2020. Data analysis was conducted with Reflexive thematic analysis. NVivo supported data management.

Results

The identified needs were individualised issues, structural factors, mental health, substance use and geographical disposition of services. There is a need for mental support and continuity of care associated with substance use. The demand for local services is vital for healthcare provision. Healthcare needs go beyond the necessity of services and health issues. They are associated with stigma in the interaction with practitioners. Institutional practices and practitioners' attitudes reinforce non-explicit forms of discrimination and health inequalities.

Conclusions

Practitioners and policymakers need to focus on the person-centred approach. They need to listen to young people. Data showed a need for specific services, like mental health and drug use. Moreover, practitioners need to avoid stigmatisation and discrimination by a caring practice. Public health and social care policies need to address stigma and access to services for young people after a custodial sentence.

Key messages

It is necessary to avoid stigmatisation and improve access to services for young people transitioning back to the community after a custodial sentence. Public Health and social care policies need to address this marginalised group by offering person-centred approaches, continuity of care and support during re-entry.

Altered atrial restitution dynamics and refractoriness in metabolic syndrome due to up-regulation of potassium repolarizing currents increases susceptibility to atrial fibrillation

Background

Metabolic alterations, such as Metabolic Syndrome (MS), describe an association of factors including diabetes, hypertension, obesity and dyslipidemia, linked to higher risk and prevalence of overall cardiovascular disease, arrhythmogenesis and sudden cardiac death. Obese and diabetic patients have shown an increased risk for developing atrial fibrillation (AF). However, underlying mechanisms are not understood.

Purpose

To study the effects of MS and obesity remodeling in atrial restitution dynamics, frequency-dependent adaptation, refractoriness and its potential susceptibility to AF.

Methods

Electrophysiological experimental data from High-fat (HF-O, standard rabbit chow with an additional 15% fat) and Hig-fat High-Sucrose Metabolic Syndrome (HFHS-MS, 10% hydrogenated coconut oil and 5% lard, 15% high-sucrose dissolved in water) rabbit models were used to adjust computational models atrial electrophysiology remodeling under each condition. Additionally, isoproterenol and AF conditions were considered to challenge both in-silico models. Validation and sensitivity analysis were performed for each model parameters. Computational simulations in conditions of pacing at different pacing cycle lengths was assessed at 100, 125, 150, 200, 250, 350, 450, 500, 650, 750, 850, 1000 ms. Restitution dynamics were automatically determined and analyzed, as well as restitution slopes and presence of automaticity, early after-depolarizations, alternans and cardiac arrhythmia induction.

Results

Shortening of action potential duration and refractoriness in the left atrium was observed under HFHS-MS. Upstroke velocity, maximum excitability and sodium availability were altered both in HF-O and HFHS-MS. HF-O remodeling showed presence of alternans at high pacing frequencies. Repolarization restitution was shortened in conditions of ISO and MS-AF. Restitution slopes were &gt;1 in HF-O and HFHS-MS, which was correlated to higher susceptibility to AF, and further increased in MS-AF. Under MS-AF, abbreviation in APD in both atria, resulted in increased reentrant frequencies in AF, which was exacerbated under IK1 up-regulation, increasing atrial vulnerability.

Conclusions

HFHS-MS underlies modifications in atrial electrophysiology including shorter refractoriness in HFHS-MS, as well as modifications in atrial excitability, which may be pro-arrhythmic mainly at high frequency rates. This could be explained in part by an up-regulation of outward potassium channels. These results could partially explain increased susceptibility for AF in MS.

Funding Acknowledgement

Type of funding sources: None.

Long-term outcomes among a cohort of 4296 implantable cardioverter-defibrillator patients: insights from the UMBRELLA study

Background

Large observational real-world studies describing modern implantable cardioverter-defibrillator (ICD) populations with long-term follow-up are lacking.

Purpose

To assess the incidence of arrhythmias in a cohort of contemporary patients undergoing ICD implant from 2005 and 2017 and to analyze the arrhythmic risk and mortality according to their clinical profiles.

Methods

UMBRELLA (NTC01561144) is a prospective, multicentre, nationwide study of ICD patients followed by remote monitoring. All device information was automatically stored through the remote monitoring system and a blinded review of all the stored arrhythmic episodes was performed. The study outcomes were first appropriate ICD therapy and all-cause death.

Results

The study population consisted of 4296 patients (61.9±12.9 years, ischaemic cardiomyopathy (ICM): n=2150, dilated cardiomyopathy (DCM): n=1166, valvular heart disease (VHD): n=119, hypertrophic cardiomyopathy (HCM): n=294, arrhythmogenic right ventricular cardiomyopathy (ARVC): n=71, Brugada syndrome (BS): n=143, long QT syndrome (LQTS): n=43, and adult congenital heart disease (ACHD): n=60)). Primary prevention (PP) was the main indication (n=2758).

During a mean follow-up of 46.6±27.3 months, 16,067 episodes of sustained ventricular arrhythmia (SVA) occurred in 1344 patients. Appropriate ICD therapy was delivered to 85.7% (n=13,767) episodes of SVA in 1173 patients (27.3% of population). A higher risk of first appropriate ICD therapy was observed in VHD (HR: 1.94, 95% CI: 1.43–2.62), ARVC (HR: 1.84, 95% CI: 1.28–2.66), ICM (HR: 1.51, 95% CI: 1.29–1.78), and DCM (HR: 1.28, 95% CI: 1.07–1.53) whereas patients with HCM (HR: 0.72, 95% CI: 0.54–0.96) and BS (HR: 0.25, 95% CI: 0.14–0.45) were at significantly lower risk (Figure 1A). In multivariate analysis (Table 1), age, gender, atrial fibrillation (AF), secondary prevention, LVEF ≤35%, and QRS width emerged as clinical predictors of appropriate ICD therapy, whereas CRT-D correlated with lower risk. An independently higher risk was found in DCM, VHD, and ARVC, and a lower risk in BS patients.

At follow-up, 590 deaths (13.4% of population) were reported. Patients with ICM (HR 3.90, 95% CI: 2.58–5.90), DCM (HR 3.33, CI 95%: 2.18–5.10), and VHD (HR 3.97, CI 95%: 2.25–6.99) had worse prognoses and it was significantly better in BS patients (HR 0.11, 95% CI: 0.01–0.67, p=0.017) (Figure 1B). In multivariate analysis, age, gender, AF, renal failure, diabetes and reduced LVEF, emerged as independent predictors of all-cause death (Table 1).

Conclusions

Irrespective of the aetiology, contemporary ICD patients with an arrhythmic substrate derived from left ventricular systolic dysfunction had a similar risk of ICD life-saving interventions and death.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Étude observationnelle d’évolution de la COVID-19 dans une population de patients hémodialysés avec étude d’impact des comorbidités

Introduction

Nos patients dialysés ont été particulièrement exposés à la pandémie de COVID-19.

Description

Nous rapportons une étude observationnelle rétrospective de notre cohorte de patients hémodialysés repliés en secteur COVID de mars 2020 à fin mars 2021 (1 an).

Méthodes

Nous avons observé dans cette population, l’âge, le sexe, l’ancienneté en dialyse, le type de variant si disponible, les comorbidités principales, la prise d’immunosuppresseurs, l’existence d’une néoplasie active, la présence d’un diabète, d’un terrain vasculaire sévère, d’une pathologie respiratoire, le lieu de vie, les symptômes au moment du diagnostic, la prise en charge et l’évolution.

Résultats

Sur cette cohorte de 122 patients, l’âge moyen est de 71 ans (médiane 72,5 ans), 11 (9 %) vivaient en EHPAD, l’ancienneté moyenne en dialyse est de 9,5 ans (médiane 6,35 ans). Quatre-vingt-douze ont contracté le virus historique (α), 15 le variant β, 3 le variant γ et 12 n’ont pas été qualifiés. Quatre patients (3 %) étaient sous immunosuppresseurs, 9 (7 %) avaient une néoplasie active dont 2 sont décédés, 58 (47,5 %) étaient diabétiques, 15 (12 %) présentaient une pathologie respiratoire dont 4 sont décédés, 86 (70,5 %) un terrain vasculaire sévère dont 18 sont décédés sur 19 décès au total. L’IMC moyen était de 26,7 (médiane 25,8). Cinq parmi les 22 patients avec troubles cognitifs sont décédés.

Soixante (49 %) ont été pris en charge à domicile.

Quarante-deux (34,4 %) patients ont été hospitalisés, 20 en réanimation dont 8 sont décédés.

Quarante-six (37,5 %) patients ont développé une forme asymptomatique, 25 (20,5 %) une forme modérée, 32 (26 %) une forme sévère et 12 (10 %) une forme grave d’emblée.

La mortalité est de 15,5 % (19 patients décédés).

Conclusion

Dans notre cohorte, la prise d’immunosuppresseurs, les troubles cognitifs, ou l’institutionnalisation ne semblent pas être des facteurs aggravants. En revanche, le terrain vasculaire sévère semble être un élément de gravité.

P–079 A spontaneous LH peak before triggering for intrauterine insemination with donor sperm (IUI-D) is associated to lower live birth rates

Study question

Are live birth rates after IUI with donor sperm (IUI-D) and controlled ovarian stimulation comparable between women with a spontaneous LH peak vs those without?

Summary answer

Biochemical, clinical, ongoing pregnancy rates and live birth rates were higher among women without an LH peak.

What is known already

It is common clinical practice to trigger ovulation in IUI cycles once specific criteria are met; if a natural LH surge appears, adjusting the IUI timing may become necessary. Pregnancy rates seem to be slightly better when IUI is scheduled in relation to the presence or absence of an LH peak in non-stimulated cycles. In IUI with stimulated cycles, however, there is no consensus in the medical literature regarding the best moment to program the IUI, due to different inclusion criteria, different IUI timing and definition of LH peak among studies.

Study design, size, duration

Retrospective cohort study of 9,657 IUI-D cycles performed between 2012 and 2019 in one fertility center. IUI-D without LH peak (n = 6,679) versus IUI-D with LH peak (n = 2,978) were compared. Differences in pregnancy outcomes between study groups were evaluated using a Pearson’s Chi2 test. A p &lt; 0.05 was considered statistically significant.

Participants/materials, setting, methods

The definition used to define an LH peak is &gt; 10UI/L in the last follicular control. In cases without an LH peak, when at least one dominant follicle reached 17mm, ovulation was triggered with human chorionic gonadotropin in the following 24h, and IUI-D was performed 38h after triggering. In cases with an LH peak, ovulation was triggered the 6h following the detection, and IUI-D was also performed 38h later.

Main results and the role of chance

The women BMI and age were comparable between groups, with a mean±SD of 35.2±4.8 years old, and 24.3±4.7 for BMI. Other characteristics such as number of previous inseminations, type of stimulation drug, initial dose, total dose, stimulation length and number of follicles &gt; 16mm in the last follicular control were also comparable. As expected, the LH level at the last follicular control was different between groups, with a mean of 5.1UI/L in the no-LH peak and 21.4IU/L in the LH peak group. The group without an LH peak had higher biochemical, clinical, ongoing and live birth rates compared to the group with LH peak: 27.7% vs. 20.7%; 19.5% vs. 15.5%; 17.7% vs. 13.7%; 16.3% vs. 12.6%, respectively (p-value&lt;0.001).

Limitations, reasons for caution

The main limitation of the study is its retrospective nature. Also, a definition of LH peak based in absolute values was used; a definition based in relative values may lead to different results.

Wider implications of the findings: A definition of LH peak based on absolute numbers is imprecise, and the cut-off of 10UI/L does not allow a good scheduling for IUI. A LH peak based on relative values could improve the detection of patients starting ovulation and the accuracy in programming IUI.

Trial registration number

Not applicable

O-171 Altered meiotic spindle morphology and composition in in vitro matured oocytes

Study question

How does the meiotic spindle tubulin PTMs of MII oocytes matured in vitro compare to that of MII oocytes matured in vivo?

Summary answer

MII cultured in vitro present detyrosinated tubulin in the spindle microtubules, while MII oocytes matured in vivo do not.

What is known already

A functional spindle is required for chromosomal segregation during meiosis, but the role of tubulin post-translational modifications (PTMs) in spindle meiotic dynamics remains poorly characterized. In contrast with GVs matured in vitro within the cumulus oophorous, in vitro maturation of denuded GVs to the MII stage (GV-MII) is associated with spindle abnormalities, chromosome misalignment and compromised developmental potential. Although aneuploidy rates in GV-MII are not higher than in vivo matured MII, disorganized chromosomes may contribute to compromised developmental potential. However, to date, spindle PTMs morphology of GV-MII has not been compared to that of in vivo cultured MII oocytes.

Study design, size, duration

GV (n = 125), and MII oocytes (n = 24) were retrieved from hormonally stimulated women, aged 20 to 35 years old. GVs were matured to the MII stage in vitro in G-2 PLUS medium for 30h; the maturation rate was 68,2%; the 46 GV-MII oocytes obtained were vitrified, stored, and warmed before fixing and subjecting to immunofluorescent analysis. In vivo matured MII oocytes donated to research were used as controls.

Participants/materials, setting, methods

Women were stimulated using a GnRH antagonist protocol, with GnRH agonist trigger. Trigger criterion was ≥2 follicles ≥18mm; oocytes were harvested 36h later. Spindle microtubules were incubated with antibodies against alpha tubulin and tubulin PTMs (acetylation, tyrosination, polyglutamylation, Δ2-tubulin, and detyrosination); chromosomes were stained with Hoechst 33342 and samples subjected to confocal immunofluorescence microscopy (ZEISS LSM780), with ImageJ software analysis. Differences in spindle morphometric parameters were assessed by non-parametric Kruskal–Wallis and Fisher’s exact tests.

Main results and the role of chance

Qualitatively, Δ2-tubulin, tyrosination and polyglutamylation were similar for both groups. Acetylation was also present in both groups, albeit in different patterns: while in vivo matured MII oocytes showed acetylation at the poles, GV-MII showed a symmetrical distribution of signal intensity, but discontinuous signal on individual microtubule tracts, suggesting apparent islands of acetylation. In contrast, detyrosination was detected in in vivo matured MII oocytes but was absent from GV-MII. Regarding spindle pole morphology, of the four possible phenotypes described in the literature (double flattened and double focused; flattened-focused, focused-flattened, with the first word characterizing the cortex side of the spindle), we observed double flat shaped spindle poles in 86% of GV-MII oocytes (25/29) as opposed to 40.5% (15/37) for the in vivo matured MII oocytes (p = 0.0004, Fisher’s exact test). Further morphometric analysis of the spindle size (maximum projection, major and minor axis length) and the metaphase plate position (proximal to distal ratio, angle) revealed decreased spindle size in GV-MII oocytes (p = 0.019, non parametric Kruskal- Wallis test).

Limitations, reasons for caution

Oocytes retrieved from hyperstimulation cycles could be intrinsically impaired since they failed to mature in vivo. Our conclusions should not be extrapolated to IVM in non-stimulated cycles, as in this model, the cumulus oophorus is a major factor in oocyte maturation and correlation with spindle dynamics has been inferred.

Wider implications of the findings

The metaphase II spindle stability compared to the mitotic or metaphase I meiotic one justifies the presence of PTMs such as acetylation and glutamylation, which are found in stable, long-lived microtubules. The significance of the absence of detyrosinated microtubules in the MII-GV group remains to be determined

Trial registration number

not applicable

The Phosphate Inhibition Paradigm: Host and Fungal Genotypes Determine Arbuscular Mycorrhizal Fungal Colonization and Responsiveness to Inoculation in Cassava With Increasing Phosphorus Supply

A vast majority of terrestrial plants are dependent on arbuscular mycorrhizal fungi (AMF) for their nutrient acquisition. AMF act as an extension of the root system helping phosphate uptake. In agriculture, harnessing the symbiosis can potentially increase plant growth. Application of the AMF Rhizophagus irregularis has been demonstrated to increase the yields of various crops. However, there is a paradigm that AMF colonization of roots, as well as the plant benefits afforded by inoculation with AMF, decreases with increasing phosphorus (P) supply in the soil. The paradigm suggests that when fertilized with sufficient P, inoculation of crops would not be beneficial. However, the majority of experiments demonstrating the paradigm were conducted in sterile conditions without a background AMF or soil microbial community. Interestingly, intraspecific variation in R. irregularis can greatly alter the yield of cassava even at a full application of the recommended P dose. Cassava is a globally important crop, feeding 800 million people worldwide, and a crop that is highly dependent on AMF for P uptake. In this study, field trials were conducted at three locations in Kenya and Tanzania using different AMF and cassava varieties under different P fertilization levels to test if the paradigm occurs in tropical field conditions. We found that AMF colonization and inoculation responsiveness of cassava does not always decrease with an increased P supply as expected by the paradigm. The obtained results demonstrate that maximizing the inoculation responsiveness of cassava is not necessarily only in conditions of low P availability, but that this is dependent on cassava and fungal genotypes. Thus, the modeling of plant symbiosis with AMF under different P levels in nature should be considered with caution.

Efficiency and efficacy of vitrification in 35 654 sibling oocytes from donation cycles

STUDY QUESTION

Is oocyte vitrification/warming as efficient and effective as using fresh oocytes in donation cycles?

SUMMARY ANSWER

IVF with vitrified donor oocytes is less efficient than using fresh oocytes, but its efficacy remains comparable to that of fresh cycles.

WHAT IS KNOWN ALREADY

Oocyte vitrification is used to preserve the reproductive potential of oocytes. A small number of randomized controlled trials carried out by experienced groups have shown that this technique provides fertilization, pregnancy, implantation and ongoing pregnancy rates comparable to those of fresh oocytes. However, large registry-based analyses have consistently reported lower live birth rates (LBRs) in cycles using vitrified oocytes. It is not clear whether this decrease may be due to the effect of vitrification per se on the oocytes or to the lower efficiency of the technique, as some of the oocytes do not survive after warming.

STUDY DESIGN, SIZE, DURATION

Retrospective cohort analysis of 1844 cycles of oocyte donation (37 520 oocytes), each donor in the study provided enough oocytes for at least one reception cycle with fresh oocytes (2561 cycles) and one reception cycle with vitrified oocytes (2471 cycles) from the same ovarian stimulation (sibling oocytes). Overall, 35 654 oocytes were considered in the analysis. All embryo transfers (n = 5032) were carried out between 2011 and 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Differences in reproductive outcomes after the first embryo transfer were evaluated using Pearson's Chi-squared test and regression analysis adjusted for recipient's age, BMI, sperm origin and state, day of embryo transfer, morphological score and number of transferred embryos. We performed two additional sub-analyses, to test whether the efficiency and/or effectiveness of vitrification/warming impacts reproductive results. One analysis included paired cycles where the same number of fresh and vitrified oocytes were available for ICSI (SAME sub-analysis), while the second analysis included those cycles with a 100% survival rate post-warming (SAME100 sub-analysis).

MAIN RESULTS AND THE ROLE OF CHANCE

Baseline and cycle characteristics of participants were comparable between groups. Overall, fertilization rates and embryo morphological scores were significantly lower (P < 0.001) when using vitrified oocytes; moreover, vitrified oocytes also resulted in lower reproductive outcomes than sibling fresh oocytes using both unadjusted and adjusted analyses: ongoing pregnancy (32.1% versus 37.5%; P < 0.001; OR 0.88, 95% CI 0.77, 1.00) and live birth (32.1% versus 31.9%; P = 0.92; OR 1.16, 95% CI 0.90, 1.49). However, when the efficiency of warming was taken into account, reproductive outcomes in recipients became comparable: ongoing pregnancy (33.5% versus 34.1%; P = 0.82; OR 1.11, 95% CI 0.87, 1.43) and LBR (32.1% versus 32%; P = 0.97; OR 1.15, 95% CI 0.89, 1.48). Moreover, after selecting only cycles that, in addition to having the same number of oocytes available for ICSI, also had 100% post-warming survival rate in the vitrified group, reproductive outcomes were also comparable between fresh and vitrified oocytes: ongoing pregnancy (34.8% versus 32.4%; P = 0.42; OR 1.32, 95% CI 0.98, 1.77) and live birth (32.9% versus 31.0%; P = 0.52; OR 1.27, 95% CI 0.95, 1.71), indicating that reproductive outcomes of these cycles are affected by the efficiency of the vitrification/warming technique performed rather than the oocyte damage due to the fast cooling process to which oocytes are subjected.

LIMITATIONS, REASONS FOR CAUTION

An open vitrification system was used for all cases, and oocyte vitrification/warming was performed by experienced embryologists with consistently high survival rates; caution must be exerted when extrapolating our results to data obtained using other open vitrification systems, closed vitrification systems or to IVF units with survival rates <90%.

WIDER IMPLICATIONS OF THE FINDINGS

This is the largest cohort study comparing reproductive outcomes of vitrified and fresh sibling donor oocytes to date. We found that, when the number of oocytes available after warming is equal to the number of fresh oocytes, reproductive results including live birth are comparable. Consequently, the efficiency of vitrification must be taken into account to achieve the same reproductive outcomes as with fresh oocytes. We recommend implementing strict indicators of vitrification/warming efficiency in clinics and refining vitrification/warming protocols to maximize survival.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by intramural funding of Clínica EUGIN and by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia (GENCAT 2015 DI 048). The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Risk factors assessment in fibular free flap mandibular reconstruction

INTRODUCTION

The fibular free flap (FFF) is the best choice method for mandibular reconstruction. However, the failure and the complications risk factors (RF) are not yet fully identified. This study aims to analyze these RF in order to improve the success rate.

MATERIAL

This retrospective study includes all patients who benefited from a FFF mandibular reconstruction between the first of January, 2014 and the thirty-first of December, 2018 in the Department of Stomatology and Maxillofacial Surgery department of the CHU Saint-Pierre Hospital, Brussels, Belgium.

RESULTS

Thirty patients benefited from this intervention. The overall success rate was 90%. Majority of the patients were men (67%) (mean age: 52 years). The main associated co-morbidities were: alcohol (50%), tobacco consumption (67%) and previous radiotherapy (20%). The mean operative time was 9,5hours. The morbidities rates at the receiving site (RS) and the donor site (DS) were respectively 43% and 30%. Infection and dehiscence of the RS were the main complications. Statistical analysis identified RF for RS infections: atherosclerosis and operative time; RS dehiscence (previous cervical dissection and secondary reconstruction); flap necrosis (ischemia time, rate of infection at the recipient site, history of radiation therapy, alcohol consumption, National Nosocomial Infection Surveillance score (NNISS), and history of cervical dissection); and DS morbidities (NNISS and dehiscence rate at the DS in the early period).

CONCLUSION

The FFF mandibular reconstruction offers a significant success rate. Nevertheless, this study highlighted several failure and complications RF of the procedure. Previous neck dissection and radiotherapy, operative and the ischemia time, were RF associated with complication at the RS. Furthermore, the NNIS score and the dehiscence rate were also reported as RF for FFF necrosis.

Hydro-climatic changes of wetlandscapes across the world

Assessments of ecosystem service and function losses of wetlandscapes (i.e., wetlands and their hydrological catchments) suffer from knowledge gaps regarding impacts of ongoing hydro-climatic change. This study investigates hydro-climatic changes during 1976-2015 in 25 wetlandscapes distributed across the world's tropical, arid, temperate and cold climate zones. Results show that the wetlandscapes were subject to precipitation (P) and temperature (T) changes consistent with mean changes over the world's land area. However, arid and cold wetlandscapes experienced higher T increases than their respective climate zone. Also, average P decreased in arid and cold wetlandscapes, contrarily to P of arid and cold climate zones, suggesting that these wetlandscapes are located in regions of elevated climate pressures. For most wetlandscapes with available runoff (R) data, the decreases were larger in R than in P, which was attributed to aggravation of climate change impacts by enhanced evapotranspiration losses, e.g. caused by land-use changes.

Undetectable viral RNA in oocytes from SARS-CoV-2 positive women

A central concern for the safe provision of ART during the current coronavirus disease 2019 (CODIV-19) pandemic is the possibility of vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through gametes and preimplantation embryos. Unfortunately, data on SARS-CoV-2 viral presence in oocytes of infected individuals are not available to date. We describe the case of two women who underwent controlled ovarian stimulation and tested positive to SARS-CoV-2 infection by PCR on the day of oocyte collection. The viral RNA for gene N was undetectable in all the oocytes analyzed from the two women.

Fiber-based angular filtering for high-resolution Brillouin spectroscopy in the 20-300 GHz frequency range

Brillouin spectroscopy emerges as a promising non-invasive tool for nanoscale imaging and sensing. One-dimensional semiconductor superlattice structures are eminently used for selectively enhancing the generation or detection of phonons at few GHz. While commercially available Brillouin spectrometers provide high-resolution spectra, they consist of complex experimental techniques and are not suitable for semiconductor cavities operating at a wide range of optical wavelengths. We develop a pragmatic experimental approach for conventional Brillouin spectroscopy that can integrate a widely tunable excitation-source. Our setup combines a fibered-based angular filtering and a spectral filtering based on a rotating single etalon and a double grating spectrometer for sequential reconstruction of Brillouin spectra. This configuration allows probing confined acoustic phonon modes in the 20-300 GHz frequency range with excellent laser rejection and high spectral resolution. Remarkably, our scheme based on the excitation and collection of the enhanced Brillouin scattering signals through the optical cavity allows for better angular filtering with decreasing phonon frequency. It can be implemented for the study of cavity optomechanics and stimulated Brillouin scattering over broadband optical and acoustic frequency ranges.

See, feel, act: Hierarchical learning for complex manipulation skills with multisensory fusion

Humans are able to seamlessly integrate tactile and visual stimuli with their intuitions to explore and execute complex manipulation skills. They not only see but also feel their actions. Most current robotic learning methodologies exploit recent progress in computer vision and deep learning to acquire data-hungry pixel-to-action policies. These methodologies do not exploit intuitive latent structure in physics or tactile signatures. Tactile reasoning is omnipresent in the animal kingdom, yet it is underdeveloped in robotic manipulation. Tactile stimuli are only acquired through invasive interaction, and interpretation of the data stream together with visual stimuli is challenging. Here, we propose a methodology to emulate hierarchical reasoning and multisensory fusion in a robot that learns to play Jenga, a complex game that requires physical interaction to be played effectively. The game mechanics were formulated as a generative process using a temporal hierarchical Bayesian model, with representations for both behavioral archetypes and noisy block states. This model captured descriptive latent structures, and the robot learned probabilistic models of these relationships in force and visual domains through a short exploration phase. Once learned, the robot used this representation to infer block behavior patterns and states as it played the game. Using its inferred beliefs, the robot adjusted its behavior with respect to both its current actions and its game strategy, similar to the way humans play the game. We evaluated the performance of the approach against three standard baselines and show its fidelity on a real-world implementation of the game.

Genetically Different Isolates of the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis Induce Differential Responses to Stress in Cassava

Water scarcity negatively impacts global crop yields and climate change is expected to greatly increase the severity of future droughts. The use of arbuscular mycorrhizal fungi (AMF) can potentially mitigate the effects of water stress in plants. Cassava is a crop that feeds approximately 800 million people daily. Genetically different isolates of the AMF R. irregularis as well as their clonal progeny have both been shown to greatly alter cassava growth in field conditions. Given that cassava experiences seasonal drought in many of the regions in which it is cultivated, we evaluated whether intraspecific variation in R. irregularis differentially alters physiological responses of cassava to water stress. In a first experiment, conducted in field conditions in Western Kenya, cassava was inoculated with two genetically different R. irregularis isolates and their clonal progeny. All cassava plants exhibited physiological signs of stress during the dry period, but the largest differences occurred among plants inoculated with clonal progeny of each of the two parental fungal isolates. Because drought had not been experimentally manipulated in the field, we conducted a second experiment in the greenhouse where cassava was inoculated with two genetically different R. irregularis isolates and subjected to drought, followed by re-watering, to allow recovery. Physiological stress responses of cassava to drought differed significantly between plants inoculated with the two different fungi. However, plants that experienced higher drought stress also recovered at a faster rate following re-watering. We conclude that intraspecific genetic variability in AMF significantly influences cassava physiological responses during water stress. This highlights the potential of using naturally existing variation in AMF to improve cassava tolerance undergoing water stress. However, the fact that clonal progeny of an AMF isolate can differentially affect how cassava copes with natural drought stress in field conditions, highlights the necessity to understand additional factors, beyond genetic variation, which can account for such large differences in cassava responses to drought.

Combustion of n-C3-C6 Linear Alcohols: An Experimental and Kinetic Modeling Study. Part I: Reaction Classes, Rate Rules, Model Lumping, and Validation

This work (and the companion paper, Part II) presents new experimental data for the combustion of n-C3-C6 alcohols (n-propanol, n-butanol, n-pentanol, n-hexanol) and a lumped kinetic model to describe their pyrolysis and oxidation. The kinetic subsets for alcohol pyrolysis and oxidation from the CRECK kinetic model have been systematically updated to describe the pyrolysis and high- and low-temperature oxidation of this series of fuels. Using the reaction class approach, the reference kinetic parameters have been determined based on experimental, theoretical, and kinetic modeling studies previously reported in the literature, providing a consistent set of rate rules that allow easy extension and good predictive capability. The modeling approach is based on the assumption of an alkane-like and alcohol-specific moiety for the alcohol fuel molecules. A thorough review and discussion of the information available in the literature supports the selection of the kinetic parameters that are then applied to the n-C3-C6 alcohol series and extended for further proof to describe n-octanol oxidation. Because of space limitations, the large amount of information, and the comprehensive character of this study, the manuscript has been divided into two parts. Part I describes the kinetic model as well as the lumping techniques and provides a synoptic synthesis of its wide range validation made possible also by newly obtained experimental data. These include speciation measurements performed in a jet-stirred reactor (p = 107 kPa, T = 550-1100 K, φ = 0.5, 1.0, 2.0) for n-butanol, n-pentanol, and n-hexanol and ignition delay times of ethanol, n-propanol, n-butanol, n-pentanol/air mixtures measured in a rapid compression machine at φ = 1.0, p = 10 and 30 bar, and T = 704-935 K. These data are presented and discussed in detail in Part II, together with detailed comparisons with model predictions and a deep kinetic discussion. This work provides new experimental targets that are useful for kinetic model development and validation (Part II), as well as an extensively validated kinetic model (Part I), which also contains subsets of other reference components for real fuels, thus allowing the assessment of combustion properties of new sustainable fuels and fuel mixtures.

Combustion of n-C3-C6 Linear Alcohols: An Experimental and Kinetic Modeling Study. Part II: Speciation Measurements in a Jet-Stirred Reactor, Ignition Delay Time Measurements in a Rapid Compression Machine, Model Validation, and Kinetic Analysis

This work presents new experimental data for n-C3-C6 alcohol, combustion (n-propanol, n-butanol, n-pentanol, n-hexanol). Speciation measurements have been carried out in a jet-stirred reactor (p = 107 kPa, T = 550-1100 K, φ = 0.5, 1.0, 2.0) for n-butanol, n-pentanol, and n-hexanol. Ignition delay times of ethanol, n-propanol, n-butanol, and n-pentanol/air mixtures were measured in a rapid compression machine at φ = 1.0, p = 10 and 30 bar, and T = 704-935 K. The kinetic subsets for alcohol pyrolysis and oxidation from the CRECK kinetic model have been systematically updated to describe the pyrolysis and high- and low-temperature oxidation of this series of fuels as described in Part I of this work (Pelucchi M.; Namysl S.; Ranzi E.Combustion of n-C3-C6 linear alcohol: an experimental and kinetic modeling study. Part I: reaction classes, rate rules, model lumping and validation. Submitted to Energy and Fuels, 2020). Part II describes in detail the facilities used for this systematic experimental investigation of n-C3-C6 alcohol combustion and presents a complete validation of the kinetic model by means of comparisons with the new data and measurements previously reported in the literature for both pyrolytic and oxidative conditions. Kinetic analyses such as rate of production and sensitivity analyses are used to highlight the governing reaction pathways and reasons for existing deviations, motivating possible further improvements in our chemistry mechanism.

Lipoxin A4 promotes reduction and antibiotic efficacy against Pseudomonas aeruginosa biofilm

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic bacterium commonly found in wound infections and airways of cystic fibrosis patients. P. aeruginosa readily forms biofilms which can reduce the efficacy of antibiotics used to eradicate the pathogen. We have previously shown that a Specialized Pro-resolving Mediator (SPM), Lipoxin A4 (LxA₄) is a quorum sensing inhibitor which can reduce P. aeruginosa virulence. In this study, we examined the direct actions of LxA₄ and RvD₂ on P. aeruginosa biofilm formation and virulence gene expression. The influence of LxA₄ on antibiotic efficacy and the combined effects on biofilm formation were also investigated. LxA₄ and RvD₂ reduced P. aeruginosa biofilm formation and virulence gene expression. LxA₄ increased ciprofloxacin inhibition on biofilm formation but did not affect ciprofloxacin's action on non-adherent bacteria. On the other hand, LxA₄ increased bacterial killing action of imipenem but did not affect imipenem's action on biofilm. We also found that LxA₄ can increase ciprofloxacin's bacterial killing ability in established biofilm. Together these results suggest that LxA₄ has direct effects on P. aeruginosa biofilm formation and can increase antibiotic efficacy directly.

Iron deficiency is associated with larger infarcts and with adverse remodeling in STEMI patients and reduces myocardial tolerance to ischemia/reperfusion by inhibiting the eNOS/sGC/PKG pathway in mice

Background

Iron deficiency (ID) interferes with the cardioprotective pathway endothelial nitric oxide synthase/soluble guanylate cyclase/protein kinase G (eNOS/sGC/PKG), but its role in acute myocardial infarction remains unclear.

Methods

Patients (n=125) with a first anterior STEMI treated with PCI underwent magnetic resonance imaging in the acute phase and at 6 months. We assessed whether ID (ferritin level &lt;100 μg/L or &lt;300 μg/L if transferrin saturation was &lt;20%) was associated with infarct size acutely or with adverse left ventricular (LV) remodeling (LV end-diastolic volume increase at 6 months &gt;20%, n=105). C57BL6/N mice were fed with standard diet or iron-deficient diet for 4 weeks before undergoing 45-min coronary occlusion/24-h reperfusion.

Results

Patients with ID (43.2%) had larger infarcts (22.8±10.2 vs 16.8±9.8% of LV mass, P=0.002) and more frequent microvascular obstruction (70.0 vs 43.3%, P=0.004) in the initial exam than the rest. They also developed adverse LV remodeling more often (38.6 vs 14.8%, P=0.005), even after adjusting by infarct size and final TIMI flow grade (OR 3.1, 95% CI 1.1–8.6, P=0.027). In mice, ID diet reduced myocardial iron content, serum ferritin and hemoglobin levels without reaching anemic values and without inducing echocardiographic alterations. ID diet reduced myocardial eNOS protein content, its dimeric form, and nitrites/nitrates and cGMP levels. eNOS decrease was associated with reduced HSP90 levels and increased eNOS ubiquitination in correlation with oxidative and nitrosative stress. Weekly iv administration of iron sucrose effectively reverted the ID-diet effects. Infarct size was larger in the ID group than in controls (58.8±3.0 vs. 40.3±3.6%, P=0.03) but was not increased in ID-diet animals treated with iron sucrose (36.3±4.0%) or receiving the sGC activator ataciguat before ischemia (31.0±2.5%).

Conclusions

ID is associated with larger infarcts and with more frequent adverse LV remodeling in patients with STEMI and reduces myocardial tolerance to ischemia/reperfusion in mice by attenuating eNOS/sGC/PKG pathway activity. Iron sucrose treatment and sGC activation reverted these deleterious effects of ID in mice. Iron supplementation might be beneficial in STEMI patients with ID.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): CIBER-CV. Instituto de Salud Carlos III (PI16/00232), co-financed by the ERDF