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.

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.

[Alzheimer's disease, amyloid-b peptides and ubiquitin-proteasome system: Therapeutic perspectives]. / Maladie d'Alzheimer, peptides ß-amyloïdes et système ubiquitine-protéasome - Perspectives thérapeutiques.

The Alzheimer's disease - an age-related neurodegenerative disorder leading to a progressive cognitive impairment - is characterized by an intracerebral accumulation of soluble ß-amyloid (Aß) oligomers, followed by the appearance of abnormally ubiquitinylated neurofibrillary tangles - a process associated with a chronic inflammation. The systematic presence of ubiquitinylated inclusions reflects a decrease in the proteasome activity due to (and contributing to) the presence of Aß oligomers - a central dysfunction in the etiology of the disease. The involvement of the ubiquitin-proteasome system opens new therapeutic perspectives for both prevention and treatment.

Title: Maladie d'Alzheimer, peptides ß-amyloïdes et système ubiquitine-protéasome - Perspectives thérapeutiques. Abstract: La maladie d'Alzheimer ­ une maladie neurodégénérative liée à l'âge entraînant une altération progressive des fonctions cognitives ­ se caractérise par une accumulation intracérébrale d'oligomères ß-amyloïdes (Aß) solubles, suivie d'une apparition d'enchevêtrements neurofibrillaires anormalement ubiquitinylés ­ un processus associé à une inflammation chronique. La présence systématique d'inclusions ubiquitinylées traduit une baisse d'activité du protéasome due (et concourant) à la présence d'oligomères Aß ­ un dysfonctionnement central dans l'étiologie de la maladie. L'implication du système ubiquitine-protéasome ouvre de nouvelles perspectives thérapeutiques tant préventives que curatives.

Première vague de la COVID-19 au Québec : motivation du personnel soignant à traiter des patients infectés.

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.

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.

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.

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.

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.

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.

P53 and PIK3CA Mutations in KRAS/HER2 Negative Ovarian Intestinal-Type Mucinous Carcinoma Associated with Mature Teratoma.

Primary ovarian intestinal-type mucinous carcinomas associated with mature teratoma are rare and represent less than 3% of all primary ovarian neoplasms. The molecular profile of these tumors is still controversial. We report here the first case of mucinous ovarian tumor in which mutation of the PIK3CA and P53 genes could be demonstrated by the next generation sequencing technique without KRAS mutation or HER2 amplification. Our data suggest that these mucinous carcinoma variants probably present an extremely complex molecular biology profile that should be known in the future to stratify therapeutic outcomes and potential targeted therapies, particularly in recurrent disease.

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

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.

Aptamer Profiling of A549 Cells Infected with Low-Pathogenicity and High-Pathogenicity Influenza Viruses.

Influenza A viruses (IAVs) are important animal and human emerging and re-emerging pathogens that are responsible for yearly seasonal epidemics and sporadic pandemics. IAVs cause a wide range of clinical illnesses, from relatively mild infections by seasonal strains, to acute respiratory distress during infections with highly pathogenic avian IAVs (HPAI). For this study, we infected A549 human lung cells with lab prototype A/PR/8/34 (H1N1) (PR8), a seasonal H1N1 (RV733), the 2009 pandemic H1N1 (pdm09), or with two avian strains, an H5N1 HPAI strain or an H7N9 strain that has low pathogenicity in birds but high pathogenicity in humans. We used a newly-developed aptamer-based multiplexed technique (SOMAscan®) to examine >1300 human lung cell proteins affected by the different IAV strains, and identified more than 500 significantly dysregulated cellular proteins. Our analyses indicated that the avian strains induced more profound changes in the A549 global proteome compared to all tested low-pathogenicity H1N1 strains. The PR8 strain induced a general activation, primarily by upregulating many immune molecules, the seasonal RV733 and pdm09 strains had minimal effect upon assayed molecules, and the avian strains induced significant downregulation, primarily in antimicrobial response, cardiovascular and post-translational modification systems.

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.

The ACURATE neo Transcatheter Heart Valve: A Comprehensive Analysis of Predictors of Procedural Outcome.

OBJECTIVES: The aim of this study was to perform a comprehensive analysis of factors that affect procedural outcomes of transcatheter aortic valve replacement using the ACURATE neo prosthesis (Symetis/Boston, Ecublens, Switzerland). BACKGROUND: Predictors of procedural outcomes using the ACURATE neo prosthesis are poorly understood. METHODS: A total of 500 patients underwent transfemoral aortic valve replacement with the ACURATE neo prosthesis. Device landing zone calcification was stratified as severe, moderate, or mild. Anatomic and procedural predictors of second-degree or greater paravalvular leakage and permanent pacemaker implantation were assessed. RESULTS: Post-procedural second-degree or greater paravalvular leakage was more frequent with increasing device landing zone calcification (mild 0.8% vs. moderate 5.0% vs. severe 13.0%; p < 0.001), whereas permanent pacemaker implantation was independent of device landing zone calcification. More severe periannular calcification (odds ratio [OR]: 1.007; 95% confidence interval [CI]: 1.003 to 1.010; p < 0.001), less oversizing (OR: 0.867; 95% CI: 0.773 to 0.971; p = 0.014), the presence of annular plaque protrusions (OR: 2.756; 95% CI: 1.138 to 6.670; p = 0.025), and aortic movement of the delivery system after full deployment (OR: 5.593; 95% CI: 1.299 to 24.076; p = 0.02), and sinotubular junction height (OR: 1.156; 95% CI: 1.007 to 1.328; p = 0.04) independently predicted second-degree or greater paravalvular leakage. Predictors of permanent pacemaker implantation were pre-existing right bundle branch block (OR: 3.122; 95% CI: 1.261 to 7.731; p = 0.01) and more oversizing (OR: 1.111; 95% CI: 1.009 to 1.222; p = 0.03). CONCLUSIONS: Successful transcatheter aortic valve replacement using the ACURATE neo device predominantly depends on careful patient selection with appropriate oversizing and taking into account the individual anatomy and calcium distribution of the aortic root.

Safety and tolerance of cidofovir as a 2% gel for local application in high-grade cervical intraepithelial neoplasia: A phase 1 investigation.

OBJECTIVES: The primary objective was to evaluate the safety and local tolerance of a topical 2% (w/w) cidofovir gel, applied directly to the cervices of women with high-grade cervical intraepithelial neoplasia (CIN 2+). The secondary objective was to evaluate the pharmacokinetics of cidofovir during the treatment. MATERIALS AND METHODS: Nine women with CIN 2+, were treated with a course of 3 g of cidofovir gel, applied locally once per week for 3 weeks in total (9 g). The treatment was administered in a cervical cap, applied to the cervix for 5 or 10 hours (n = 6 and 3 patients, respectively). Follow-up included a structured questionnaire, a gynecological examination, blood analysis for hematology, C-reactive protein (CRP), and renal function assessment plus pharmacokinetic analyses of cidofovir after each treatment and at the end of the full course. RESULTS: No clinically significant hematological/biochemical abnormalities or serious adverse events (SAE) were reported, although 6 mild to moderate adverse events (AE) occurred in relation to the study drug: 1 flu-like syndrome and 5 local AEs. Plasma concentrations of cidofovir were very low (mean Cmax of 103.0 and 99.2 ng/mL after 5 and 10 hours of exposure, respectively). CONCLUSION: Cidofovir, directly applied on CIN 2+, is reasonably well tolerated and the systemic exposure following topical application is much lower than that seen with intravenous administration, at the approved dose.
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