An organic O donor for biological hydroxylation reactions

All biological hydroxylation reactions are thought to derive the oxygen atom from one of three inorganic oxygen donors, O2, H2O2, or H2O. Here, we have identified the organic compound prephenate as the oxygen donor for the three hydroxylation steps of the O2-independent biosynthetic pathway of ubiquinone, a widely distributed lipid coenzyme. Prephenate is an intermediate in the aromatic amino acid pathway and genetic experiments showed that it is essential for ubiquinone biosynthesis in Escherichia coli under anaerobic conditions. Metabolic labeling experiments with 18O-shikimate, a precursor of prephenate, demonstrated the incorporation of 18O atoms into ubiquinone. The role of specific iron-sulfur enzymes belonging to the widespread U32 protein family is discussed. Prephenate-dependent hydroxylation reactions represent a unique biochemical strategy for adaptation to anaerobic environments.

[Big data and artificial intelligence in anesthesia : Reality or fiction?]

Big data and artificial intelligence are buzzwords that everyone is talking about and yet always provide a touch of science fiction to the scenery. What is the status of these topics in anesthesia? Are the first robots already rolling through the corridors while doctors are getting bored as all the work has been done? Spoiler alert! We are still far away from achieving this. Initially, paper charts and analogue notes stand in the way of comprehensive digitization. Source systems need to be merged and data standardized, harmonized and validated. Therefore, the friendly android that is rolling towards us, waving and holding a freshly brewed cup of coffee in our thoughts will have to wait; however, a glimpse of the future is already evident in some clinics and the first promising developments are already showing what could be the standard tomorrow. Learning algorithms calculate the length of stay individually for each patient in the intensive care unit (ICU), reducing negative consequences such as readmission and mortality. The field of ultrasound technology for regional anesthesia and closed-loop anesthesia systems is also demonstrating the benefits of artificial intelligence (AI)-assisted technologies in practice. The efforts are diverse and ambitious but they repeatedly collide with privacy challenges and significant capital expenditure, which weigh heavily on an already financially strained healthcare system; however, anyone who listens carefully to the medical staff knows that robots are not what they would expect and the buzzwords big data and artificial intelligence might be less science fiction than initially assumed.

Sonographic Aeration Scoring Indicates Disease Severity in Critically Ill Patients with COVID-19

AIMS AND METHODS

We evaluated an ultrasound score from 0 to 32 points in eight pulmonary regions to monitor critically ill COVID-19 patients. The score was correlated to surrogate parameters of disease severity, i.e., the oxygenation index, respiratory support, mortality, plasma interleukin-6, and WHO and ARDS classifications.

RESULTS

A total of 27 patients were repeatedly examined, and 71 examinations were evaluated. Patients with severe COVID-19 scored higher (median 17) than those with moderate disease (median 11, p < 0.01). The score did not differentiate between stages of ARDS as defined by the Berlin criteria (p = 0.1) but could discern ARDS according to the revised ESICM definition (p = 0.002). Non-survivors had higher ultrasound scores than survivors (median 18.5 vs. 14, p = 0.04). The score correlated to the oxygenation index (ρ = -0.56, p = 0.03), and changes in the score between examinations correlated to changes in oxygenation (ρ = -0.41, p = 0.16). The correlation between the score and interleukin-6 was ρ = 0.35 (p < 0.001). The interrater reliability for the score was ICC = 0.87 (p < 0.001).

CONCLUSIONS

The ultrasound score is a reliable tool that might help monitor disease severity and may help stratify the risk of mortality.

P-455 Laparoscopic robot-assisted autologous transplantation of cryopreserved ovarian tissue: report of an operative technique and reproductive outcomes in a case series

Study question

Is laparoscopic robot-assisted autologous transplantation of ovarian tissue feasible and is the reproductive outcome adequate in comparison with published data?

Summary answer

Laparoscopic robot-assisted autologous transplantation of ovarian tissue is feasible and safe. The reproductive outcome in our series is comparable with published data.

What is known already

Autologous cryopreserved ovarian tissue transplantation (ACOTT) is recognized as a valid fertility preservation technique among young patients facing iatrogenic premature ovarian failure (IOP). Orthotopic transplantation consists in the reimplantation of ovarian tissue back to the medulla of the ovary or into a specially created peritoneal pouch. It has been described by laparoscopy or mini laparotomy. It is the most efficient technique to restore endocrine function and fertility. Conception and live birth rates have been reported to be respectively 38% and 26%. The robot-assisted laparoscopic approach was recently described in a 7-case series.

Study design, size, duration

We prospectively registered all ACOTT procedures performed in our department between November 2004 and January 2022.

Participants/materials, setting, methods

We analyzed the data of 29 ACOTT procedures performed among 22 patients. The indication for ovarian cryopreservation, the time to restore and duration of endocrine function (regular menstrual cycles), time to first pregnancy and number of pregnancies/live births have been prospectively collected. The operative technique (laparoscopic/robot), duration of surgical procedure, hospital stay, intra and post-operative complications have been retrospectively extracted from the patients’ files.

Main results and the role of chance

We included 22 patients: 8 with a malignant hematologic disease, 7 with a breast cancer, 3 with a benign disease, 2 with a pelvic malignancy and 2 with a sarcoma. Their median age at ovarian tissue cryopreservation was 28.5 (11 – 35) years. Their median age at first ACOTT was 36.5 (23 – 42) years. The median time between cryopreservation and ACOTT was 6.75 (2 – 21) years. Seven out of 22 patients had a second ACOTT. Twenty-nine procedures of orthotopic reimplantation were performed. A concomitant heterotopic (sub cutaneous) transplantation was performed among six out of the 29 procedures, at the beginning of our experience. All 29 orthotopic reimplantation were performed laparoscopically, 19 out of them with robot assistance. The median operating time was 102 (43 – 149) minutes and was shorter for laparoscopy (62 minutes) than for robot assisted laparoscopy (106 minutes). We encountered no complication, and the median hospital stay was 1 (1 – 2) day. The median time to restore endocrine function was 4 (1 – 6) months. Eighteen transplanted patients wished to be pregnant among whom 12 (67%) had at least one pregnancy and 8 (44%) had at least one live birth.

Limitations, reasons for caution

This is a small sample within a single institution. The patients were referred from many centers for ovarian tissue cryopreservation and secondary ACOTT. They were followed until they became pregnant and then referred to their gynecologist. Finally, three patients who did not wish to conceive were lost of follow-up.

Wider implications of the findings

This case series confirms the feasibility and safety of robot assisted ACOTT. The procedure is longer when performed with the robot. The fertility outcome (pregnancy/livebirth rates) is comparable with the published data. The added value of the robot approach needs to be investigated in larger series with long term follow-up.

Trial registration number

P2004/122

Coherent and Incoherent Tunneling into Yu-Shiba-Rusinov States Revealed by Atomic Scale Shot-Noise Spectroscopy

The pair breaking potential of individual magnetic impurities in s-wave superconductors generates localized states inside the superconducting gap commonly referred to as Yu-Shiba-Rusinov (YSR) states whose isolated nature makes them promising building blocks for artificial structures that may host Majorana fermions. One of the challenges in this endeavor is to understand their intrinsic lifetime, ℏ/Λ, which is expected to be limited by the inelastic coupling with the continuum thus leading to decoherence. Here we use shot-noise scanning tunneling microscopy to reveal that electron tunneling into superconducting 2H-NbSe_{2} mediated by YSR states is not Poissonian, but ordered as a function of time, as evidenced by a reduction of the noise. Moreover, our data show the concomitant transfer of charges e and 2e, indicating that incoherent single particle and coherent Andreev processes operate simultaneously. From the quantitative agreement between experiment and theory we obtain Λ=1  μeV≪k_{B}T demonstrating that shot noise can probe energy scales and timescales inaccessible by conventional spectroscopy whose resolution is thermally limited.

Evolution in caesarean section practices in North Kivu: Impact of caregiver training

Introduction

A caesarean section is a major obstetric procedure that can save the life of mother and child. Its purpose is to protect the mother’s health from the complications of childbirth and to protect the baby’s health. In sub-Saharan Africa (SSA), there are major inequalities in access to caesarean sections and significant variations in practices to determine the indications for the procedure. Periodic analyses of maternal deaths have shown that more than half of maternal and new born deaths are due to suboptimal care and are therefore potentially preventable. The objective of our study is to assess the impact of health staff training under the PADISS project (to support the health system’s integrated development) on the quality of CS procedures in North Kivu, by comparing two periods.

Material and methods

The populations compared were recruited from the referral hospitals in North Kivu, DRC (Democratic Republic of Congo). The first (group 1) was made up of patient files studied retrospectively for the period from 01/11/2013 to 01/01/2016. The second group (group 2), studied prospectively, comprised patient files from June 2019 to January 2020. Obstetric, maternal and foetal data were compared. Statistical analyses were performed using STATA/IC 15.0 for Windows. Univariate and multiple logistic regression was performed to determine which characteristics are associated with maternal and perinatal morbidity and mortality. A p value < 0.05 was considered statistically significant.

Results

CS frequency was approximately 17% in both study periods. We observed a CS frequency of about 34% at North Kivu provincial hospital for the two populations studied. The main indications for CS were dystocia, foetal distress and scarred uterus for both populations. In the population studied prospectively, after the implementation of health staff training, there were fewer incidence rate of dystocia, foetal distress and neonatal death, a more complete patient record, shorter hospital stay, and fewer blood transfusions but more incidence rate of scarred uterus, post-operative complications and low birth weight. Intervention had no statistically significant impact on low birth weight (OR = 1.9, p = 0.13), on neonatal mortality (OR = 0.69, p = 0.21).

Conclusion

Our study shows a decrease in neonatal deaths, dystocia and foetal distress, but an increase in post-operative complications, maternal deaths and cases of scarred uterus and low birth weight. However, multiple logistic regression did no support the conclusion.

Exact law for compressible pressure-anisotropic magnetohydrodynamic turbulence: Toward linking energy cascade and instabilities

We derive an exact law for compressible pressure-anisotropic magnetohydrodynamic turbulence. For a gyrotropic pressure tensor, we study the double-adiabatic case and show the presence of new flux and source terms in the exact law, reminiscent of the plasma instability conditions due to pressure anisotropy. The Hall term is shown to bring ion-scale corrections to the exact law without affecting explicitly the pressure terms. In the pressure isotropy limit we recover all known results obtained for isothermal and polytropic closures. The incompressible limit of the gyrotropic system leads to a generalization of the Politano and Pouquet's law where a new incompressible source term is revealed and reflects exchanges of the magnetic and kinetic energies with the no-longer-conserved internal energy. We highlight the possibilities offered by the new laws to investigate potential links between turbulence cascade and instabilities widely observed in laboratory and astrophysical plasmas.

Bonnes pratiques en matière de télémédecine

La télémédecine ou médecine à distance s’est imposée aux soignants à la faveur de la pandémie à SARS-Cov2. Elle doit être considérée comme un outil capable d’améliorer la pratique d’une médecine moderne. Ce texte en rappel les règles d’exercice et incite à en organiser l’enseignement.

[First wave of COVID-19 in Quebec: Healthcare workers' motivation to treat infected patients]

INTRODUCTION

Retention of healthcare workers (HCWs) in the healthcare system during the COVID-19 pandemic could become a challenge. It is therefore important to better understand what are the motivational elements that could explain a greater or lesser motivation to care for infected patients.

OBJECTIVES

To evaluate factors modulating HCWs' willingness to treat COVID-19 infected patients.

METHODS

HCWs from Québec, Canada, were invited to complete an online survey during the first wave of the COVID-19 pandemic between the months of April and July 2020. The survey focused on the intention to avoid treating infected patients, prior experiences in treating COVID-19 patients and anxiety levels. Descriptive statistics and multiple regression analysis were used to assess which factors explained differences in HCWs intention to avoid treating patients.

RESULTS

A total of 430 HCW completed the survey. A majority were women (87%) and nurses (50%). Of those, 12% indicated having considered measures to avoid working with COVID-19 infected patients and 5% indicated having taken actions to avoid working with infected patients. A further 18% indicated that they would use a hypothetical opportunity to avoid working with infected patients. Having previously treated infected patients was associated with a significant reduction in the intention to avoid work (OR: 0.56 CI 0.36-0.86). Amongst HCWs, physicians had a significantly reduced intention to avoid treating infected patients (OR: 0.47 CI 0.23-0.94). We also found that an increase in anxiety score was associated with a greater intention to avoid treating COVID-19 infected patients (OR: 1.06 CI 1.04-1.08).

CONCLUSION

Study results suggest that previous experience in treating COVID-19 infected patients is protective in terms of work-avoidance intentions. We also found that amongst HCWs, physicians had a significantly lower intention to avoid working with COVID-19 infected patients. Finally, our results show that increase in anxiety is associated with a higher intention to avoid treating infected patients. Characterization of factors associated with low anxiety levels and low reluctance to work during the COVID-19 pandemic could be useful in staffing facilities during the present and future healthcare crisis.

A highly virulent variant of HIV-1 circulating in the Netherlands

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log₁₀ increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.

An enzymatic activation of formaldehyde for nucleotide methylation

Folate enzyme cofactors and their derivatives have the unique ability to provide a single carbon unit at different oxidation levels for the de novo synthesis of amino-acids, purines, or thymidylate, an essential DNA nucleotide. How these cofactors mediate methylene transfer is not fully settled yet, particularly with regard to how the methylene is transferred to the methylene acceptor. Here, we uncovered that the bacterial thymidylate synthase ThyX, which relies on both folate and flavin for activity, can also use a formaldehyde-shunt to directly synthesize thymidylate. Combining biochemical, spectroscopic and anaerobic crystallographic analyses, we showed that formaldehyde reacts with the reduced flavin coenzyme to form a carbinolamine intermediate used by ThyX for dUMP methylation. The crystallographic structure of this intermediate reveals how ThyX activates formaldehyde and uses it, with the assistance of active site residues, to methylate dUMP. Our results reveal that carbinolamine species promote methylene transfer and suggest that the use of a CH₂O-shunt may be relevant in several other important folate-dependent reactions.

CNS-3 status remains an independent adverse prognosis factor in children with acute lymphoblastic leukemia (ALL) treated without cranial irradiation: Results of EORTC Children Leukemia Group study 58951

AIM

To evaluate the prognostic significance of initial central nervous system (CNS) involvement of children with acute lymphoblastic leukemia (ALL) enrolled in the EORTC 58951 trial.

PATIENTS AND METHODS

From 1998 to 2008, 1930 ALL patients were included in the randomized EORTC 58951 trial. Overall treatment intensity was adjusted according to known prognostic factors including the level of minimal residual disease after induction treatment. CNS-directed therapy comprised four to 11 courses of i.v. methotrexate (5g/m²), and 10 to 19 intrathecal chemotherapy injections, depending on risk group and CNS status. Cranial irradiation was omitted for all patients.

RESULTS

The overall 8-year event-free survival (EFS) and overall survival (OS) rates were 81.3% and 88.1%, respectively. In the CNS-1, TPL+, CNS-2, and CNS-3 groups, the 8-year EFS rates were 82.1%, 77.1%, 78.3%, and 57.4%, respectively. Multivariable analysis indicated that initial CNS-3 status, but not CNS-2 or TLP+, was an independent adverse predictor of outcome. The 8-year incidence of isolated CNS relapse was 1.7% and of isolated or combined CNS relapse it was 3.7%. NCI high-risk group, male sex, CNS-2 and CNS-3 status were independent predictors for a higher incidence of any CNS relapse.

CONCLUSIONS

CNS-3 status remains associated with poor prognosis and requires intensification of both systemic and CNS-directed therapy. This trial was registered at https://clinicaltrials.gov/under/NCT00003728.

Intraoperative Evaluation of Resection Margins in Breast-Conserving Surgery for In Situ and Invasive Breast Carcinoma

Background:

The challenge of breast-conserving surgery (BCS) is to remove the entire tumour with free margins and avoid secondary excision that may adversely affect the cosmetic outcome. Consequently, intraoperative evaluation of surgical margins is critical. The aims of this study were multiple. First, to analyse our methodology of intraoperative examination of the resection margins and to evaluate radiological and pathological methods in the assessment of the surgical margins. Second, to evaluate the factors associated with positive margins in our patient population.

M&m:

The data on the resection margin status of 290 patients who underwent BCS for invasive carcinoma or ductal carcinoma in situ (DCIS) between 2009 and 2016 were reviewed.

Results:

In the cohort of BCS with invasive carcinoma, the negative predictive value was 97.4% for intraoperative assessment by radiography and 81.8% for intraoperative assessment by pathology. The re-operation rate among cases without intraoperative assessment was 23.6% compared to 7.3% among cases with intraoperative assessment (P = .003). Margin status was significantly associated with tumour size, histological subtype (invasive lobular carcinoma), and multifocality. In the population of BCS with DCIS, margin status was significantly associated with preoperative localisation and intraoperative margin assessment (P = .03).

Conclusion:

There is no statistical difference between pathological and radiological intraoperative assessment. Tumour size, lobular subtype, and multifocality were found to be significantly associated with positive margins in cases with invasive carcinoma, whereas absence of intraoperative margin assessment was significantly associated with positive margins in cases with DCIS. Therefore, intraoperative margin assessment improves the likelihood of complete excision of the lesion.

How anxious were Quebec healthcare professionals during the first wave of the COVID-19 pandemic? A web-based cross-sectional survey

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic may cause significant anxiety among healthcare professionals (HCPs). COVID-19-related psychological impacts on HCPs in Western countries have received relatively little attention.

OBJECTIVE

This study aims to assess the levels of anxiety in HCPs working in the province of Quebec (Canada) during the first wave of the COVID-19 pandemic and identify factors associated with changes in anxiety scores.

METHODS

An exploratory online cross-sectional survey was conducted among Quebec HCPs from April to July 2020. The Spielberger's State-Trait Anxiety Inventory (STAI) was used to measure state anxiety among HCPs. Descriptive and multivariate analyses were performed.

RESULTS

A total of 426 HCPs completed the survey. Anxiety scores ranged from 20 to 75 points, with 80 being the highest possible value on the STAI scale. Being a female HCP [B = 5.89, 95% confidence interval (CI): 2.49-9.3] and declaring having the intention to avoid caring for patients with COVID-19 (B = 3.75, 95% CI: 1.29-6.22) were associated with increased anxiety scores. Having more years of experience was associated with decreased anxiety scores [B = -0.2, 95% CI: -0.32-(-0.08)].

CONCLUSION

Organizational strategies aimed at preventing and relieving anxiety should target junior female HCPs who express the intention to avoid caring for patients with COVID-19. Seniority could become an important criterion in selecting frontline HCPs during pandemics. Further studies are needed to comprehensively examine the impacts of the COVID-19 pandemic on Canadian HCPs and identify evidence-based coping strategies.

Inhibition of RANK signaling in breast cancer induces an anti-tumor immune response orchestrated by CD8+ T cells

Most breast cancers exhibit low immune infiltration and are unresponsive to immunotherapy. We hypothesized that inhibition of the receptor activator of nuclear factor-κB (RANK) signaling pathway may enhance immune activation. Here we report that loss of RANK signaling in mouse tumor cells increases leukocytes, lymphocytes, and CD8⁺ T cells, and reduces macrophage and neutrophil infiltration. CD8⁺ T cells mediate the attenuated tumor phenotype observed upon RANK loss, whereas neutrophils, supported by RANK-expressing tumor cells, induce immunosuppression. RANKL inhibition increases the anti-tumor effect of immunotherapies in breast cancer through a tumor cell mediated effect. Comparably, pre-operative single-agent denosumab in premenopausal early-stage breast cancer patients from the Phase-II D-BEYOND clinical trial (NCT01864798) is well tolerated, inhibits RANK pathway and increases tumor infiltrating lymphocytes and CD8⁺ T cells. Higher RANK signaling activation in tumors and serum RANKL levels at baseline predict these immune-modulatory effects. No changes in tumor cell proliferation (primary endpoint) or other secondary endpoints are observed. Overall, our preclinical and clinical findings reveal that tumor cells exploit RANK pathway as a mechanism to evade immune surveillance and support the use of RANK pathway inhibitors to prime luminal breast cancer for immunotherapy.

Receptor activator of nuclear factor-κB (RANK)/RANK-ligand (RANKL) signaling regulates the tumor-immune crosstalk. Here the authors show that systemic RANKL inhibition promotes CD8 + T cell infiltration in patients with early breast cancer and that loss of RANK signaling in tumor cells drives a T cell-dependent anti-tumor response in preclinical models.

Invasive ductal carcinoma arising in borderline phyllode tumor: A potential role of PIK3CA mutation

•

Invasive carcinomatous lesions associated with borderline phyllodes tumors are extremely rare.

•

Molecular biological mechanisms associated with this kind of lesions are unknown.

•

PIK3CA gene mutation could be implicated in the development of these lesions.

Introduction

Carcinomatous lesions associated with phyllodes tumors are extremely rare and are found in less than 1% of all cases. To date, the molecular biological mechanisms associated with this carcinomatous transformation remain unknown.

Presentation of case

We present here the case of a 61-year-old patient with invasive ductal of no special type (NST) carcinoma originating in a borderline phyllode tumor with mutation in the PIK3CA gene.

Discussion

To the best of our knowledge, this mutation has never been described in this type of association.

Conclusion

Based on these data, we can better understand the ethiopathogenic molecular mechanisms in this type of lesion. Consequently, they could also in the future give rise to new therapeutic alternatives.

[Anti-infective treatment in obesity-"just double it?"]

Adaequate antibiotic therapy is crucial for successful anti-infective therapy. In addition to the choice of the right antibiotic and the duration of therapy, the dose also plays a decisive role. Obesity has an influence on the pharmacokinetics of antibiotics, which can lead to underdosing if previous weight-independent dosing regimes are used. It is therefore necessary to carry out systematic measurements of concentrations in obese patients. Since pharmacokinetic differences between plasma and the interstitial fluid of different target tissues have been observed for different antibiotics, the measurement is also necessary in the target tissue. The technique of microdialysis is best suited for this purpose as it allows concentrations to be measured continuously in the target tissue.

Oncoplastic Management of a Giant Buschke Lowenstein Genital Tumor in a Nonimmunocompromised Patient

Buschke-Löwenstein tumor (BLT) is a rare but impressive and aggressive entity and is mostly associated with Human Papilloma Virus (HPV) 6 or 11 infection in immunocompromised patients. It stands out because of the importance of the recurrences and the risk of progression to a malignant tumor. The first-line treatment remains local radical surgery. Other treatments are controversial, including radiotherapy, chemotherapy, and immunotherapy. We report a new case regarding the management of a giant BLT in a non-immunocompromised woman, treated in a three-staged approach, starting with a radical excisional surgery, followed by a delayed reconstruction and then radiotherapy.

[Focus on the endocannabinoid system and the reprotoxicity of marijuana in female users]

Among recreative compounds, marijuana is the most used worldwide. Delta9THC binding on brain endocannabinoid receptors drives its psychotropic effects. The endocannabinoid system (ECS) is an endogenous neurohormonal system essential for homeostasis composed of ligands, metabolic enzymes and at least 2 receptors discovered to date. In female reproduction, the ECS regulates the hypothalamic-pituitary axis and many steps of the reproduction process, such as ovulation, tubal transportation and trophoblast implantation. Delta9THC can cross the placental barrier and bind to the fetal endocannabinoid system. In humans, fetal and obstetrical consequences of marijuana use during pregnancy are intrauterine growth restriction and preterm delivery. In the light of legalization projects currently reviewed in several western countries, further research should be conducted to improve knowledge on maternal, fetal and reprotoxic consequences of marijuana use during reproductive age and pregnancy.

Photoelectrocatalytic activity of In(iii)-modified TiO2 photoanodes in the visible spectrum region

Nanocrystalline film photoanodes of titanium dioxide modified with In(iii) ions in the concentration range from 1.0 to 10 mass% (0.23 to 2.52 at%) are manufactured using the sol–gel method.

Complex diffractive surface patterns on metals by UV-ps laser ablation

Diffractive surface patterns with complex textures are generated on metal surfaces by picosecond UV laser ablation using an interference setup. Two diffraction gratings with variable distance and rotation angle provide a huge variety of interference patterns and thus resulting surface topographies. This variety can be further enhanced by selecting or blocking particular beams. A correlation analysis of the complex diffraction patterns generated by reflection of visible laser light at these surface topographies demonstrates that patterns with slightly differing fabrication parameters (variation of 0.5 mm in distance or 1° in rotation) can be clearly distinguished.

[Special situations of preconditioning and prehabilitation in oncological visceral surgery]

BACKGROUND

Prehabilitation prior to complex visceral oncological surgery is playing an increasingly important role.

OBJECTIVE

The aim of this review article is to present special situations of preconditioning in visceral oncological patient cohorts. The following conditions were defined as special situations with subsequently increased risk profile: cardiopulmonary comorbidities, geriatric patients, neoadjuvant therapy and simultaneous fatigue.

MATERIAL AND METHODS

A selective literature review based on a search in the electronic databases MEDLINE, PubMed, Cochrane Library and the International Standard Randomization Controlled Trial Number (ISRCTN) was performed.

RESULTS

The identification of high-risk patients is an essential part of the preoperative evaluation conducted by the anesthesiologist prior to surgery. The cardiovascular and the pulmonary risk profile are determined by means of prediction indices evaluating patient-specific and surgery-related risk factors. The increased use of new oral anticoagulants and dual platelet aggregation inhibition requires individualized treatment strategies. Numerous studies have shown clinically relevant effects of exercise therapy interventions throughout all phases of oncological treatment. In addition to positive effects on therapy-associated side effects, sport can also counteract the effects of sedentary behavior in cancer patients and improve the health-related quality of life. The effectiveness of sport and exercise therapies as well as psychological interventions in oncological patients with fatigue (CRF) is broad, with important components being motivation and compliance.

DISCUSSION

In high-risk patients an interdisciplinary approach to planning and conduction of prehabilitation is essential for the early detection and optimization of perioperative risk factors and potential complications. The aim is faster recovery, reduced morbidity and mortality and the possibility to improve long-term survival and quality of life.

Measurement of soft tissue drug concentrations in morbidly obese and non-obese patients - A prospective, parallel group, open-labeled, controlled, phase IV, single center clinical trial

Background

Pharmacokinetic (PK) and pharmacodynamic (PD) data on perioperative antibiotic prophylaxis or antibiotic therapy are rare in patients suffering from morbid obesity. Furthermore, dosing regimens should be based on PK/PD models that ensure effective antibiotic exposure not in plasma, but primarily at the site of infection, mostly in the interstitial fluid (ISF). The aim of this trial is to investigate whether current dosing regimens of various antibiotics lead to effective concentrations in the ISF of morbidly obese patients.

Methods

We designed a prospective, parallel group, open-labeled, controlled single center trial to investigate the plasma and tissue pharmacokinetics of the antibiotics linezolid, meropenem, tigecycline, piperacillin/tazobactam, fosfomcyine, cefazolin, metronidazole and as secondary aim the analgesics metamizole and acetaminophen. Inclusion criteria comprise body mass index ≥35 kg/m² for obese or between 18.5 and 30 kg/m² for non-obese patients scheduled for elective abdominal surgery. For PK analysis, blood and microdialysate samples of subcutaneous tissue were collected 0–8 h after study drug administration. The primary endpoint is to investigate a possible dependency of the area-under-the-curve (AUC_0-8) in the interstitial fluid on body weight and obesity with population based pharmacokinetic analysis.

Discussion

Inadequate dosing regimes of antibiotics may be a relevant factor for morbidity and mortality of patients, as well as for the development of bacterial antibiotic resistance. The measurement of plasma and tissue concentrations will provide information necessary for PK/PD-modelling. These data about antibiotic PK/PDcharacteristics in soft tissue and their dependence on weight should help to develop weight-dependent models for calculation of patient's individual doses of different antibiotics.

Trial registration

EU clinical trials register (EudraCT-No. 2012-004383-22) and German Clinical trials Register (DRKS00004776);

Individualized positive end-expiratory pressure in obese patients during general anaesthesia: a randomized controlled clinical trial using electrical impedance tomography

Background

General anaesthesia leads to atelectasis, reduced end-expiratory lung volume (EELV), and diminished arterial oxygenation in obese patients. We hypothesized that a combination of a recruitment manoeuvre (RM) and individualized positive end-expiratory pressure (PEEP) can avoid these effects.

Methods

Patients with a BMI ≥35 kg m -2 undergoing elective laparoscopic surgery were randomly allocated to mechanical ventilation with a tidal volume of 8 ml kg -1 predicted body weight and (i) an RM followed by individualized PEEP titrated using electrical impedance tomography (PEEP IND ) or (ii) no RM and PEEP of 5 cm H 2 O (PEEP 5 ). Gas exchange, regional ventilation distribution, and EELV (multiple breath nitrogen washout method) were determined before, during, and after anaesthesia. The primary end point was the ratio of arterial partial pressure of oxygen to inspiratory oxygen fraction ( P aO 2 / F iO 2 ).

Results

For PEEP IND ( n =25) and PEEP 5 ( n =25) arms together, P aO 2 / F iO 2 and EELV decreased by 15 kPa [95% confidence interval (CI) 11-20 kPa, P <0.001] and 1.2 litres (95% CI 0.9-1.6 litres, P <0.001), respectively, after intubation. Mean ( sd ) PEEP IND was 18.5 (5.6) cm H 2 O. In the PEEP IND arm, P aO 2 / F iO 2 before extubation was 23 kPa higher (95% CI 16-29 kPa; P <0.001), EELV was 1.8 litres larger (95% CI 1.5-2.2 litres; P <0.001), driving pressure was 6.7 cm H 2 O lower (95% CI 5.4-7.9 cm H 2 O; P <0.001), and regional ventilation was more equally distributed than for PEEP 5 . After extubation, however, these differences between the arms vanished.

Conclusions

In obese patients, an RM and higher PEEP IND restored EELV, regional ventilation distribution, and oxygenation during anaesthesia, but these differences did not persist after extubation. Therefore, lung protection strategies should include the postoperative period.

Clinical trial registration

German clinical trials register DRKS00004199, www.who.int/ictrp/network/drks2/en/ .

Quantification of stromal reaction in breast carcinoma and its correlation with tumor grade and free progression survival

Cancer progression results from a complex interplay between tumor cells and the extracellular milieu. In breast carcinoma, the stromal microenvironment has been suggested to play a major role in promoting tumor growth, progression, and invasion. The stroma of 154 resected specimens of invasive breast carcinoma of no special type was quantified using a digital image analyzer. Statistical analyses were performed between the quantity of stroma and survival, as well as between progression-free survival and clinicopathological data. Levels of myofibroblastic stroma varied from 0-46%, with a median of 15.1% and a standard deviation of 7.5. The myofibroblastic stromal reaction was statistically greater in grade 2 and 3 tumors (p = 0.029). Furthermore, there was a trend for worse progression-free survival in the group of node-negative tumors with strong smooth-muscle actin stromal expression (Log rank = 0.075). The present study demonstrates that the myofibroblastic reaction of breast invasive carcinoma of no special type is not merely a passive reaction, but seems to be an integral part of the neoplastic process by facilitating tumor progression and invasion. Additional, larger studies on mechanisms of stromal change are needed and may potentially lead to novel treatments.

Abstract PD5-06: The immunomodulatory potential of denosumab in breast cancer: results from D-BEYOND, a window of opportunity trial evaluating a RANK-ligand (RANKL) inhibitor and its biological effects in young pre-menopausal women diagnosed with early breast cancer

Background

Breast cancer (BC) in young women has unique biology and poor prognosis. Previous reports suggest that they often express RANKL, which was also shown to play a role in mammary tumorigenesis and various immune processes. Here, we present the primary results of D-BEYOND, a window study investigating the biological activity of the RANKL inhibitor; denosumab in pre-menopausal BC patients.

Methods

D-BEYOND is a prospective, phase Iia, single-arm, multicenter study assessing the effect of denosumab on BC biology in premenopausal women with early BC (NCT01864798). Patients received two subcutaneous injections of denosumab (120mg), one week apart, followed by breast surgery. The primary endpoint was geometric mean change in tumor Ki67 assessed by immunohistochemistry (IHC). Blood, tumor and normal adjacent breast tissue were collected pre- and post-treatment. Serum levels of RANKL, OPG and CTX were assessed by ELISA. RNA was extracted from fresh-frozen tissue and RNAseq was performed. DESeq2 was used for differential expression analysis, GAGE was used for pathway analysis and CIBERSORT was used to infer immune cell subsets between pre- and post-treatment. Ki67, CD4/Foxp3 and CD4/CD8 IHC were performed on FFPE tissue to further assess the immune microenvironment. The percentage of TILs was independently evaluated by two pathologists on H&E slides. Pre- and post-treatment values were compared using a paired t-test.

Results

A total of 27 patients were enrolled in the study between October 2013 and July 2016. The median age was 45 years (range 35-51 years). Tumors of 21 patients were hormone receptor positive (77.8%), 4 were HER2 positive (14.8%) and 2 were triple negative (7.4%). No serious adverse events were reported, the most frequent non-serious adverse event being arthralgia (14.8%). After treatment, serum levels of CTX and RANKL decreased in all patients (P &lt; 0.001) whereas OPG increased in 76.9% of patients (P = 0.009, 95% CI 0.56-0.91). There was no significant reduction of Ki67 values from baseline (geometric mean [GM] change after treatment; 0.98, 95% CI 0.76-1.26; P = 0.90). Twenty-four pre- and post-treatment tumor pairs were available for RNAseq, IHC and TILs evaluation. There was a significant increase in the percentage of stromal TILs after treatment (GM change of 1.75, 95% CI 1.28–2.39; P = 0.001). 1084 differentially expressed genes were identified and pathway analysis revealed enrichment of several immune processes. CIBERSORT revealed an enrichment of CD8+ T cells (GM change 1.72, 95% CI 1.19–2.48; P = 0.006) and a decrease of Treg cells (0.71, 95% CI 0.52–0.98, P = 0.040). These results were confirmed by IHC of CD8+ and CD4+/Foxp3+ cells (GM change 1.59, 95% CI 1.14–2.21; P = 0.008 and 0.63, 95% CI 0.49–0.83, P = 0.001, respectively).

Conclusion

Short course of denosumab did not reduce tumor proliferation rate. However, it induced a significant increase in TILs and CD8 cytotoxic T cells, while Treg infiltration decreased. These findings suggest an immunomodulatory role for denosumab in young breast cancer and that its use in combination could boost immunotherapy efficacy.

Citation Format: Nguyen B, Marion M, Salgado R, Venet D, Vuylsteke P, Polastro L, Wieldiers H, Simon P, Lindeman G, Larsimont D, Van den Eynden G, Velghe C, Rothe F, Garaud S, Michiels S, Willard-Gallo K, Azim Jr HA, Loi S, Piccart M, Sotiriou C. The immunomodulatory potential of denosumab in breast cancer: results from D-BEYOND, a window of opportunity trial evaluating a RANK-ligand (RANKL) inhibitor and its biological effects in young pre-menopausal women diagnosed with early breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD5-06.