Clinical implications of airway obstruction with normal or low FEV1 in childhood and adolescence.

BACKGROUND: Airway obstruction is defined by spirometry as a low forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio. This impaired ratio may originate from a low FEV1 (classic) or a normal FEV1 in combination with a large FVC (dysanaptic). The clinical implications of dysanaptic obstruction during childhood and adolescence in the general population remain unclear. AIMS: To investigate the association between airway obstruction with a low or normal FEV1 in childhood and adolescence, and asthma, wheezing and bronchial hyperresponsiveness (BHR). METHODS: In the BAMSE (Barn/Child, Allergy, Milieu, Stockholm, Epidemiology; Sweden) and PIAMA (Prevention and Incidence of Asthma and Mite Allergy; the Netherlands) birth cohorts, obstruction (FEV1:FVC ratio less than the lower limit of normal, LLN) at ages 8, 12 (PIAMA only) or 16 years was classified as classic (FEV1

Alternative Splicing Is a Major Factor Shaping Transcriptome Diversity in Mild and Severe COPD.

The role of alternative splicing in Chronic Obstructive Pulmonary Disease (COPD) is still largely unknown. We aimed to investigate the differences in alternatively splicing events between patients with mild-to-moderate and severe COPD compared to non-COPD controls and to identify splicing factors associated with aberrant alternative splicing in COPD. For this purpose, we performed genome-wide RNA-seq analysis of bronchial brushings from 23 mild-to-moderate, 121 severe COPD patients, and 23 non-COPD controls. We found a significant difference in the frequency of alternative splicing events in mild-to-moderate and severe COPD compared to non-COPD controls. There were from 2x to 8x (depending on event type) more differential alternative splicing events in the severe than in the mild-to-moderate stage. The samples from severe COPD patients showed less intron retention and more exon skipping. Interestingly, the transcript levels of the top 10 differentially expressed splicing factors were significantly correlated with the percentage of many alternatively spliced transcripts in severe COPD. The aberrant alternative splicing in severe COPD was predicted to increase the overall protein-coding capacity of gene products. In conclusion, we observed large and significant differences in alternative splicing between bronchial samples of COPD and control individuals, with more events observed in severe than in mild-to-moderate COPD. The changes in the expression of several splicing factors correlated with prevalence of alternative splicing in severe COPD. Alternative splicing can indirectly impact gene expression by changing the relative abundance of protein-coding isoforms potentially influencing pathophysiological changes. The presented results provide a better understanding of COPD-related alternative splicing changes.

Asthma and rhinitis control in adolescents and young adults: A real-world MASK-air study.

BACKGROUND: In allergic rhinitis and asthma, adolescents and young adult patients are likely to differ from older patients. We compared adolescents, young adults and adults on symptoms, control levels, and medication adherence. METHODS: In a cross-sectional study (2015-2022), we assessed European users of the MASK-air mHealth app of three age groups: adolescents (13-18 years), young adults (18-26 years), and adults (>26 years). We compared them on their reported rhinitis and asthma symptoms, use and adherence to rhinitis and asthma treatment and app adherence. Allergy symptoms and control were assessed by means of visual analogue scales (VASs) on rhinitis or asthma, the combined symptom-medication score (CSMS), and the electronic daily control score for asthma (e-DASTHMA). We built multivariable regression models to compare symptoms or medication accounting for potential differences in demographic characteristics and baseline severity. RESULTS: We assessed 965 adolescent users (15,252 days), 4595 young adults (58,161 days), and 15,154 adult users (258,796 days). Users of all three age groups displayed similar app adherence. In multivariable models, age groups were not found to significantly differ in their adherence to rhinitis or asthma medication. These models also found that adolescents reported lower VAS on global allergy, ocular, and asthma symptoms (as well as lower CSMS) than young adults and adults. CONCLUSIONS: Adolescents reported a better rhinitis and asthma control than young adults and adults, even though similar medication adherence levels were observed across age groups. These results pave the way for future studies on understanding how adolescents control their allergic diseases.

Airway epithelial cell response to RSV is mostly impaired in goblet and multiciliated cells in asthma.

BACKGROUND: In patients with asthma, respiratory syncytial virus (RSV) infections can cause disease exacerbation by infecting the epithelial layer of the airways, inducing subsequent immune response. The type I interferon antiviral response of epithelial cells upon RSV infection is found to be reduced in asthma in most-but not all-studies. Moreover, the molecular mechanisms causing the differences in the asthmatic bronchial epithelium in response to viral infection are poorly understood. METHODS: Here, we investigated the transcriptional response to RSV infection of primary bronchial epithelial cells (pBECs) from patients with asthma (n=8) and healthy donors (n=8). The pBECs obtained from bronchial brushes were differentiated in air-liquid interface conditions and infected with RSV. After 3 days, cells were processed for single-cell RNA sequencing. RESULTS: A strong antiviral response to RSV was observed for all cell types, for all samples (p<1e-48). Most (1045) differentially regulated genes following RSV infection were found in cells transitioning to secretory cells. Goblet cells from patients with asthma showed lower expression of genes involved in the interferon response (false discovery rate <0.05), including OASL, ICAM1 and TNFAIP3. In multiciliated cells, an impairment of the signalling pathways involved in the response to RSV in asthma was observed. CONCLUSION: Our results highlight that the response to RSV infection of the bronchial epithelium in asthma and healthy airways was largely similar. However, in asthma, the response of goblet and multiciliated cells is impaired, highlighting the need for studying airway epithelial cells at high resolution in the context of asthma exacerbation.

Evidence to support test interpretation: Evaluating the content validity of a new item set for the Transition Pragmatics Interview.

PURPOSE: There is little consensus on evidence-based practice guidelines for the selection of criterion-referenced assessments. Having confidence in scores from criterion-referenced assessments requires evidence that items align with their intended constructs. The purposes of these studies were to demonstrate evidence of content validity for the revised item set of a developing social communication assessment and to provide clinicians with a model of content validity evaluations that can be generalised to the review of other assessments. METHOD: In Study 1, 10 experts rated 25 newly-developed items for how well they represented the intended construct. In Study 2, seven participants ages 14-20 were administered the Three Step Test Interview to assess their cognitive processes for responding to new items. Examinee responses were coded for construct-relevant and construct-irrelevant factors. RESULT: Twenty-three of the 25 newly-developed items were deemed representative of the intended construct by experts and elicited construct-relevant response processes from examinees. CONCLUSION: The integration of expert review and examinee cognitive interviewing provides a more complete evaluation of the alignment of the items to their intended construct. Transparent reports of the methods and findings of content validity studies strengthen the ability of clinicians to select criterion-referenced assessments that support valid decisions.

Major drivers of soil acidification over 30 years differ in paddy and upland soils in China.

Elevated nitrogen (N) fertilization has largely increased crop production in China, but also increased acidification risks, thereby threatening crop yields. However, natural soil acidification due to bicarbonate (HCO3) leaching and base cation (BC) removal by crop harvest also affect soil acidity whereas the input of HCO3 and BC via fertilizers and manure counteract soil acidification. Insights in rates and drivers of soil acidification in different land use types is too limited to support crop- and site-specific mitigation strategies. In this study, we assessed the historical changes in cropland acidification rates and their drivers for the period 1985-2019 at 151 sites in a typical Chinese county with the combined nutrient and soil acidification model VSD+. VSD+ could well reproduce long-term changes in pH and in the BC concentrations of calcium, magnesium and potassium between 1985 and 2019 in non-calcareous soils. In paddy soils, the acidity production rate decreased from 1985 onwards, mainly driven by a pH-induced reduction in HCO3 leaching and N transformations. In upland soils, however, acidity production was mainly driven by N transformations and hardly changed over time. Crop BC removal by harvesting played a minor role in both paddy and upland soils, but its relative importance increased in paddy soils. The acidity input was partly neutralized by HCO3 input from fertilizers and manure, which decreased over time due to a change from ammonia bicarbonate to urea. Soil buffering by both BC and aluminium release decreased in paddy soils due to a reduction in net acidity production, while it stayed relatively constant in upland soils. We conclude that acidification management in paddy soils requires a focus on avoiding high HCO3 leaching whereas the management in upland soils should focus on balancing N with recycling organic manure and crop residues.

Comparison of particles in exhaled air and multiple breath washout for assessment of small airway function in children with cystic fibrosis.

BACKGROUND: The introduction of modulator therapy for cystic fibrosis (CF) has led to an increased interest in the detection of small airway disease (SAD) as sensitive marker of treatment response. The particles in exhaled air (PExA) method, which records exhaled particle mass (PEx ng/L) and number (PExNR), detects SAD in adult patients. Our primary aim was to investigate if PExA outcomes in children with CF are different when compared to controls and associated with more severe disease. Secondary aims were to assess feasibility and repeatability of PExA in children with CF and to correlate PExA to multiple breath nitrogen washout (MBNW) as an established marker of SAD. METHODS: Thirteen healthy children (HC), 17 children with CF with normal lung function (CF-N) (FEV1 z-score ≥ -1.64) and six with airway obstruction (CF-AO) (FEV1 z-score < -1.64) between 8 and 18 years performed MBNW followed by PExA and spirometry. Children with CF repeated the measurements after 3 months. RESULTS: PEx ng/L and PExNR/L per liter of exhaled breath were similar between the three groups. The lung clearance index (LCI) was significantly higher in both CF-N and CF-AO compared to HC. All participants, except one, were able to perform PExA. Coefficient of variation for PEx ng/l was (median) 0.38, range 0-1.25 and PExNR/l 0.38, 0-1.09. Correlation between LCI and PEx ng/l was low, rs 0.32 (p = .07). CONCLUSION: PExA is feasible in children. In contrast to LCI, PExA did not differentiate healthy children from children with CF suggesting it to be a less sensitive tool to detect SAD.

Comprehensive evaluation of smoking exposures and their interactions on DNA methylation.

BACKGROUND: Smoking impacts DNA methylation, but data are lacking on smoking-related differential methylation by sex or dietary intake, recent smoking cessation (<1 year), persistence of differential methylation from in utero smoking exposure, and effects of environmental tobacco smoke (ETS). METHODS: We meta-analysed data from up to 15,014 adults across 5 cohorts with DNA methylation measured in blood using Illumina's EPIC array for current smoking (2560 exposed), quit < 1 year (500 exposed), in utero (286 exposed), and ETS exposure (676 exposed). We also evaluated the interaction of current smoking with sex or diet (fibre, folate, and vitamin C). FINDINGS: Using false discovery rate (FDR < 0.05), 65,857 CpGs were differentially methylated in relation to current smoking, 4025 with recent quitting, 594 with in utero exposure, and 6 with ETS. Most current smoking CpGs attenuated within a year of quitting. CpGs related to in utero exposure in adults were enriched for those previously observed in newborns. Differential methylation by current smoking at 4-71 CpGs may be modified by sex or dietary intake. Nearly half (35-50%) of differentially methylated CpGs on the 450 K array were associated with blood gene expression. Current smoking and in utero smoking CpGs implicated 3049 and 1067 druggable targets, including chemotherapy drugs. INTERPRETATION: Many smoking-related methylation sites were identified with Illumina's EPIC array. Most signals revert to levels observed in never smokers within a year of cessation. Many in utero smoking CpGs persist into adulthood. Smoking-related druggable targets may provide insights into cancer treatment response and shared mechanisms across smoking-related diseases. FUNDING: Intramural Research Program of the National Institutes of Health, Norwegian Ministry of Health and Care Services and the Ministry of Education and Research, Chief Scientist Office of the Scottish Government Health Directorates and the Scottish Funding Council, Medical Research Council UK and the Wellcome Trust.

Genetics of preschool wheeze and its progression to childhood asthma.

Wheezing is a common and heterogeneous condition in preschool children. In some countries, the prevalence can be as high as 30% and up to 50% of all children experience wheezing before the age of 6. Asthma often starts with preschool wheeze, but not all wheezing children will develop asthma at school age. At this moment, it is not possible to accurately predict which wheezing children will develop asthma. Recently, studying the genetics of wheeze and the childhood-onset of asthma have grown in interest. Childhood-onset asthma has a stronger heritability in comparison with adult-onset asthma. In early childhood asthma exacerbations, CDHR3, which encodes the receptor for Rhinovirus C, was identified, as well as IL33, and the 17q locus that includes GSDMB and ORMDL3 genes. The 17q locus is the strongest wheeze and childhood-onset asthma locus, and was shown to interact with many environmental factors, including smoking and infections. Finally, ANXA1 was recently associated with early-onset, persistent wheeze. ANXA1 may help resolve eosinophilic inflammation. Overall, despite its complexities, genetic approaches to unravel the early-onset of wheeze and asthma are promising, since these shed more light on mechanisms of childhood asthma-onset. Implicated genes point toward airway epithelium and its response to external factors, such as viral infections. However, the heterogeneity of wheeze phenotypes complicates genetic studies. It is therefore important to define accurate wheezing phenotypes and forge larger international collaborations to gain a better understanding of the pathways underlying early-onset asthma.

Which fetal growth charts should be used in France? Position of the French College of Obstetricians and Gynecologists (CNGOF).

OBJECTIVE: To assess which fetal growth charts best describe intrauterine growth in France defined as the ability to classify 10% of fetuses below the 10th percentile (small for gestational age [SGA]) and above the 90th percentile (large for gestational age [LGA]) in the second and third trimesters. METHODS: We analyzed five studies on fetal ultrasound measurements using three French data sources. Two studies used second and third trimester ultrasound data from a nationwide birth cohort in 2011 (the ELFE study, N = 13 197 and N = 7747); one study used third trimester ultrasound data from on a nationwide cross-sectional study (the 2016 French National Perinatal Survey, N = 9940); and the last two studies were from the "Flash study" 2014 which prospectively collected ultrasound data from routine visits in the second and third trimesters (N = 4858 and N = 3522). For each study, we reported the percentage of measurements below the 10th percentile or above the 90th percentile, using French, Hadlock's, WHO and Intergrowth (IG) charts. RESULTS: WHO classified 4.7% and 16.3% of fetuses as having an estimated fetal weight (EFW) <10th and >90th percentiles in the second trimester compared to 3.3% and 34.7% with IG. The percentage of fetuses in the third trimester with an EFW <10th and >90th percentiles, ranged from 9.1% to 9.4% and from 8.0% to 11.1%, respectively, for WHO, and from 3.9% to 4.1% and from 17.3% to 21.6%, respectively, for IG. The WHO and IG charts for head circumference were very similar and performed well. Compared to the WHO charts, the French and Hadlock's charts deviated more frequently from the target percentiles values for EFW and biometric measures. CONCLUSION: It is recommended to use the WHO charts for the assessment of EFW and ultrasound biometric measurements in France (strong recommendation; low quality of evidence).

Lack of a transcriptional response of primary bronchial epithelial cells from patients with asthma and controls to IL-33.

IL-33 and IL-1RL1 are well-replicated asthma genes that act in a single pathway toward type-2 immune responses. IL-33 is expressed by basal epithelial cells, and the release of IL-33 upon epithelial damage can activate innate lymphoid cells, T helper-2 cells, basophilic granulocytes, and mast cells through a receptor complex containing IL-1RL1. However, it is unknown how bronchial epithelial cells respond to IL-33, and whether this response is increased in the disease. We aimed to characterize the IL-33-driven transcriptomic changes in cultured primary bronchial epithelial cells from patients with asthma and healthy controls. Primary bronchial epithelial cells (PBECs) were obtained by bronchial brushing from six healthy control for air-liquid interface (ALI) cultures, whereas we selected eight healthy controls and seven patients with asthma for epithelial organoid cultures. We then stimulated the cultures for 24 h with recombinant IL-33 (rhIL33) at various concentrations with 1, 10, and 50 ng/mL for the ALI cultures and 20 ng/mL and 100 ng/mL for the organoid cultures, followed by RNA-sequencing and differential gene expression analysis. We did not detect any genome-wide significant differentially expressed genes after stimulation of PBECs with IL-33, irrespective of growth in three-dimensional (3-D) epithelial organoids or after differentiation in ALI cultures. These results were identical between PBECs obtained from patients with asthma or from healthy control subjects. We detected very low levels of IL-1RL1 gene expression in these airway epithelial cell cultures. We conclude that bronchial epithelial cells do not have a transcriptional response to IL-33, independent of their differentiation state. Hence, the airway epithelium acts as a source of IL-33 but does not seem to contribute to the response upon release of the alarmin after epithelial damage.NEW & NOTEWORTHY The IL-33/IL-1RL1 pathway stands as a formidable genetic predisposition for asthma, with ongoing clinical developments of various drugs designed to mitigate its influence in patients with asthma. The absence of a transcriptomic reaction to IL-33 within the bronchial epithelium holds significance in the pursuit of identifying biomarkers that can aid in pinpointing those individuals who would derive the greatest benefit from therapies targeting the IL-33 pathway.

Nasal epithelial gene expression and total IgE in children and adolescents with asthma.

BACKGROUND: Little is known about nasal epithelial gene expression and total IgE in youth. OBJECTIVE: We aimed to identify genes whose nasal epithelial expression differs by total IgE in youth, and group them into modules that could be mapped to airway epithelial cell types. METHODS: We conducted a transcriptome-wide association study of total IgE in 469 Puerto Ricans aged 9 to 20 years who participated in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study, separately in all subjects and in those with asthma. We then attempted to replicate top findings for each analysis using data from 3 cohorts. Genes with a Benjamini-Hochberg-adjusted P value of less than .05 in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study and a P value of less than .05 in the same direction of association in 1 or more replication cohort were considered differentially expressed genes (DEGs). DEGs for total IgE in subjects with asthma were further dissected into gene modules using coexpression analysis, and such modules were mapped to specific cell types in airway epithelia using public single-cell RNA-sequencing data. RESULTS: A higher number of DEGs for total IgE were identified in subjects with asthma (n = 1179 DEGs) than in all subjects (n = 631 DEGs). In subjects with asthma, DEGs were mapped to 11 gene modules. The top module for positive correlation with total IgE was mapped to myoepithelial and mucus secretory cells in lower airway epithelia and was regulated by IL-4, IL5, IL-13, and IL-33. Within this module, hub genes included CDH26, FETUB, NTRK2, CCBL1, CST1, and CST2. Furthermore, an enrichment analysis showed overrepresentation of genes in signaling pathways for synaptogenesis, IL-13, and ferroptosis, supporting interactions between interleukin- and acetylcholine-induced responses. CONCLUSIONS: Our findings for nasal epithelial gene expression support neuroimmune coregulation of total IgE in youth with asthma.

Age-dependent loss of cohesion protection in human oocytes.

Aneuploid human eggs (oocytes) are a major cause of infertility, miscarriage, and chromosomal disorders. Such aneuploidies increase greatly as women age, with defective linkages between sister chromatids (cohesion) in meiosis as a common cause. We found that loss of a specific pool of the cohesin protector protein, shugoshin 2 (SGO2), may contribute to this phenomenon. Our data indicate that SGO2 preserves sister chromatid cohesion in meiosis by protecting a "cohesin bridge" between sister chromatids. In human oocytes, SGO2 localizes to both sub-centromere cups and the pericentromeric bridge, which spans the sister chromatid junction. SGO2 normally colocalizes with cohesin; however, in meiosis II oocytes from older women, SGO2 is frequently lost from the pericentromeric bridge and sister chromatid cohesion is weakened. MPS1 and BUB1 kinase activities maintain SGO2 at sub-centromeres and the pericentromeric bridge. Removal of SGO2 throughout meiosis I by MPS1 inhibition reduces cohesion protection, increasing the incidence of single chromatids at meiosis II. Therefore, SGO2 deficiency in human oocytes can exacerbate the effects of maternal age by rendering residual cohesin at pericentromeres vulnerable to loss in anaphase I. Our data show that impaired SGO2 localization weakens cohesion integrity and may contribute to the increased incidence of aneuploidy observed in human oocytes with advanced maternal age.

DFT investigation of the regioselective allylation of pyrimidine 2'-deoxynucleosides.

To understand the regioselectivity observed in the allylation of pyrimidine nucleosides and to identify the factors directing the reaction, a theoretical study of the regioselective allylation was carried out. Several key points were considered such as: the structure of the deprotonated nucleobase in the presence of Na+; the effect of the solvent on the dissociation and aggregation reactions of thymidine/Na+ ion pair; and the likely allylation reaction mechanisms involved. The results showed that the regioselectivity observed experimentally can be attributed to a greater stability of a dimeric form coupled to an increase of the reaction barrier in THF due to larger Na+ binding to the nucleobase.

An epithelial gene signature of trans-IL-6 signaling defines a subgroup of type 2-low asthma.

BACKGROUND: Asthma is stratified into type 2-high and type 2-low inflammatory phenotypes. Limited success has been achieved in developing drugs that target type 2-low inflammation. Previous studies have linked IL-6 signaling to severe asthma. IL-6 cooperates with soluble-IL-6Rα to activate cell signaling in airway epithelium. OBJECTIVE: We sought to study the role of sIL-6Rα amplified IL-6 signaling in airway epithelium and to develop an IL-6+ sIL-6Rα gene signature that may be used to select asthma patients who potentially respond to anti-IL-6 therapy. METHODS: Human airway epithelial cells were stimulated with combinations of IL-6, sIL-6Rα, and inhibitors, sgp130 (Olamkicept), and anti-IL-6R (Tocilizumab), to assess effects on pathway activation, epithelial barrier integrity, and gene expression. A gene signature was generated to identify IL-6 high patients using bronchial biopsies and nasal brushes. RESULTS: Soluble-IL-6Rα amplified the activation of the IL-6 pathway, shown by the increase of STAT3 phosphorylation and stronger gene induction in airway epithelial cells compared to IL-6 alone. Olamkicept and Tocilizumab inhibited the effect of IL-6 + sIL-6Rα on gene expression. We developed an IL-6 + sIL-6Rα gene signature and observed enrichment of this signature in bronchial biopsies but not nasal brushes from asthma patients compared to healthy controls. An IL-6 + sIL-6Rα gene signature score was associated with lower levels of sputum eosinophils in asthma. CONCLUSION: sIL-6Rα amplifies IL-6 signaling in bronchial epithelial cells. Higher local airway IL-6 + sIL-6Rα signaling is observed in asthma patients with low sputum eosinophils.

Anti-COVID-19 measures and lifestyle changes during theCOVID-19 pandemic and sleep patterns in the Netherlands: a longitudinal study.

Although there is scientific evidence for an increased prevalence of sleep disorders during the COVID-19 pandemic, there is still limited information on how lifestyle factors might have affected sleep patterns. Therefore, we followed a large cohort of participants in the Netherlands (n=5,420) for up to one year (September 2020-2021) via monthly web-based questionnaires to identify lifestyle changes (physical activity, smoking, alcohol consumption, electronic device use, and social media use) driven by anti-COVID-19 measures and their potential associations with self-reported sleep (latency, duration, and quality). We used the Containment and Health Index (CHI) to assess the stringency of anti-COVID-19 measures and analyzed associations through multilevel ordinal response models. We found that more stringent anti-COVID-19 measures were associated with higher electronic device use (Odds Ratio per Interquartile Range (IQR) increase in CHI: 1.47, 95% CI: 1.40-1.53), less physical activity (OR: 0.94, 95% CI: 0.90-0.98), lower alcohol consumption frequency (OR: 0.63, CI: 0.60-0.66) and longer sleep duration (OR: 1.11, 95% CI: 1.05-1.16). Lower alcohol consumption frequency and higher electronic device use and social media use were associated with longer sleep latency. Lower physical activity levels and higher social media and electronic device use were related to poorer sleep quality and shorter sleep duration.

Gene signatures in U-BIOPRED severe asthma for molecular phenotyping and precision medicine: time for clinical use.

INTRODUCTION: The use and generation of gene signatures have been established as a method to define molecular endotypes in complex diseases such as severe asthma. Bioinformatic approaches have now been applied to large omics datasets to define the various co-existing inflammatory and cellular functional pathways driving or characterizing a particular molecular endotype. AREAS COVERED: Molecular phenotypes and endotypes of Type 2 inflammatory pathways and also of non-Type 2 inflammatory pathways, such as IL-6 trans-signaling, IL-17 activation, and IL-22 activation, have been defined in the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes dataset. There has also been the identification of the role of mast cell activation and of macrophage dysfunction in various phenotypes of severe asthma. EXPERT OPINION: Phenotyping on the basis of clinical treatable traits is not sufficient for understanding of mechanisms driving the disease in severe asthma. It is time to consider whether certain patients with severe asthma, such as those non-responsive to current therapies, including Type 2 biologics, would be better served using an approach of molecular endotyping using gene signatures for management purposes rather than the current sole reliance on blood eosinophil counts or exhaled nitric oxide measurements.

Diffuse Optical Monitoring of Cerebral Hemodynamics and Oxygen Metabolism during and after Cardiopulmonary Bypass: Hematocrit Correction and Neurological Vulnerability.

Cardiopulmonary bypass (CPB) provides cerebral oxygenation and blood flow (CBF) during neonatal congenital heart surgery, but the impacts of CPB on brain oxygen supply and metabolic demands are generally unknown. To elucidate this physiology, we used diffuse correlation spectroscopy and frequency-domain diffuse optical spectroscopy to continuously measure CBF, oxygen extraction fraction (OEF), and oxygen metabolism (CMRO2) in 27 neonatal swine before, during, and up to 24 h after CPB. Concurrently, we sampled cerebral microdialysis biomarkers of metabolic distress (lactate-pyruvate ratio) and injury (glycerol). We applied a novel theoretical approach to correct for hematocrit variation during optical quantification of CBF in vivo. Without correction, a mean (95% CI) +53% (42, 63) increase in hematocrit resulted in a physiologically improbable +58% (27, 90) increase in CMRO2 relative to baseline at CPB initiation; following correction, CMRO2 did not differ from baseline at this timepoint. After CPB initiation, OEF increased but CBF and CMRO2 decreased with CPB time; these temporal trends persisted for 0-8 h following CPB and coincided with a 48% (7, 90) elevation of glycerol. The temporal trends and glycerol elevation resolved by 8-24 h. The hematocrit correction improved quantification of cerebral physiologic trends that precede and coincide with neurological injury following CPB.

FIGO opinion paper: Drivers and solutions to the cesarean delivery epidemic with emphasis on the increasing rates in Africa and Southeastern Europe.

Cesarean delivery rates are rapidly increasing in Southeastern Europe (to more than 60%), North Africa (with a rate as high as 72% in Egypt), and in urban areas in Southern Africa (a rate of over 50% in Lagos, Nigeria). Data on the background to these increases are scarce, but likely to include poor birthing facilities in general hospitals, convenience for the doctor, private medicine, fear of litigation, socioeconomic status, shortage of midwives and nurses, and disappearance of vaginal instrumental deliveries. Options to reverse cesarean delivery trends are discussed. In this context there is a need to be better informed about how women are being counseled regarding vaginal or cesarean delivery. The long-term consequences in subsequent pregnancies for mothers and children may well be largely ignored, while these risks are highest in LMICs where higher birth numbers are desired. FIGO has begun discussions with obstetric and gynecologic societies, healthcare bodies, and governments in several countries discussed in this article, to find ways to lower the cesarean delivery rate. The requests came from the countries themselves, which may prove beneficial in helping advance progress.