Assessment of Sleep Quality in Spanish Twin Pregnancy: An Observational Single-Center Study.

Women with twin pregnancies experience greater sleep disturbance compared to women with singleton pregnancies. The aims of this study were to explore the sleep quality in women with twin pregnancies and to compare their sleep dimensions with coetaneous single pregnancies. This was an observational study in which women were enrolled at the end of pregnancy in the Obstetric Service of Hospital La Paz (Spain). The women were classified as single (n = 143) or twin pregnancy (n = 62). Pregnant women responded to the Pittsburgh Sleep Quality Index to evaluate sleep quality, latency, duration, efficiency, perturbance, use of medication, and daytime dysfunction. The higher the index, the greater the alteration of sleep quality. Without statistical differences, a poor sleep quality was higher in women with single (66.7%) than women with twin pregnancies (22.8%). The good sleeper slept 6.8 h/day in single pregnancy and 7.3 h/day in twin pregnancy. The sleep perturbation and dysfunctionality were higher in women with twin than single pregnancies. The use of medication to sleep was significantly lower in women with twin than single pregnancies. In women with twin pregnancy, the body weight gain during first trimester had a positive correlation with worse sleep quality and sleep perturbations. Twin pregnancy needed more than 7 h/day to have a high sleep quality, showing greater sleep perturbations and daytime dysfunction than single pregnancies. The control of gestational body weight can improve the sleep quality, disturbances, and duration in twin gestations. Sleep screening during pregnancy would be necessary to handle sleep issues and increase benefits in twin gestational outcomes.

The influence of air pollution on gestational age at delivery and birthweight in patients with or without respiratory allergy: A nested case-control study.

INTRODUCTION: Air pollution is a current major health issue. The burden of airborne pollutants and aeroallergen levels varies throughout the year, as well as their interaction and consequences. Prenatal exposure during pregnancy has been associated with adverse perinatal outcomes. The aim of this study was to evaluate the impact of air pollutants on perinatal outcomes in patients with or without respiratory allergy. MATERIAL AND METHODS: Nested case-control retrospective study on 3006 pregnant women. Correlations between concentrations of common pollutants in each trimester of pregnancy and on average during the whole pregnancy and both gestational age at delivery and birthweight were studied. Pearson's correlation coefficient and binary logistic regression were used. RESULTS: In general, pollutants correlated more strongly with birthweight than with gestational age at delivery. Nine-month NO2 , SO2 , CO, and benzene, and second-trimester CO negatively correlated with birthweight, whereas only first-trimester NO2 showed a very mild correlation with gestational age at delivery. Negative correlations between pollutants and birthweight were much stronger in the respiratory allergy group (n = 43; 1.4%) than in the non-allergic group. After adjustments, the most significant predictive pollutant of birthweight was SO2 in both groups. The best predictive model was much stronger in the allergic group for third-trimester SO2 (R2 = 0.12, p = 0.02) than in the non-allergic group for total SO2 (R2 = 0.002, p = 0.02). For each unit that SO2 increased, birthweight reduced by 3.22% vs. 1.28% in each group, respectively. CONCLUSIONS: Air pollutant concentrations, especially SO2 , negatively influenced birthweight. The impact of this association was much stronger and more relevant in the group of women with respiratory allergies.

Single fetal demise in monochorionic twins: How to predict cerebral injury in the survivor co-twin?

INTRODUCTION: The aims of the study were to evaluate perinatal outcome in monochorionic (MC) twins complicated with single intrauterine fetal death, spontaneously vs after fetal therapy, and to assess antenatal events that increase the risk of cerebral injury. MATERIAL AND METHODS: Historical cohort study of MC pregnancies with single intrauterine fetal death diagnosed or referred to a tertiary referral hospital (2012-2020). Adverse perinatal outcome included termination of pregnancy, perinatal death, abnormal fetal or neonatal neuroimaging and abnormal neurological development. RESULTS: A total of 68 MC pregnancies with single intrauterine fetal death after 14 weeks of gestation were included. Sixty-five (95.6%) occurred in complicated MC pregnancies (twin to twin transfusion syndrome: 35/68 [51.5%]; discordant malformation: 13/68 [19.1%], selective intrauterine growth restriction: 10/68 [14.7%], twin reversed arterial perfusion sequence: 5/68 [7.3%] and cord entanglement in monoamniotic twins: 2/68 [2.94%]). In 52 cases (76.5%) single intrauterine fetal demise occurred after fetal therapy and in 16 (23.5%) occurred spontaneously. Cerebral damage included 14/68 cases (20.6%): 6/68 cases (8.82%) were prenatal lesions and 8/68 cases (11.8%) were postnatal. Risk of cerebral damage tended to be higher in the spontaneous death group (6/16, 37.5%) compared to the therapy-group (8/52, 15.38%) (p = 0.07). The risk increased with gestational age at intrauterine death (OR 1.21, 95% CI: 1.04-1.41, p = 0.014) and was higher in those surviving co-twins who developed anemia (OR 9.27, 95% CI: 1.50-57.12, p = 0.016). Pregnancies complicated with selective intrauterine growth restriction tended to be at higher risk for neurological damage (OR 2.85, 95% CI: 0.68-11.85, p = 0.15). Preterm birth rate (<37 weeks of pregnancy) was 61.7% (37/60). Seven of eight postnatal cerebral lesions (87.5%) were related to extreme prematurity. Overall perinatal survival rate was 88.3% (57/68) and 7% (4/57) of children had an abnormal neurological outcome. CONCLUSIONS: Risk of cerebral damage in single intrauterine fetal death is especially high when it occurs spontaneously. Gestational age at single intrauterine fetal death, selective intrauterine growth restriction and anemia of the surviving co-twin are the main predictors for prenatal lesions and might be useful in parent counseling. Abnormal postnatal neurological outcome is closely related to extreme prematurity.

Influence on operative time of immediate skin-to-skin care in low-risk primary cesarean births for breech presentation: Retrospective cohort study.

BACKGROUND: Multiple benefits for both, mother and baby have been reported from immediate skin-to-skin care (SSC). The aim of this study was to analyze the influence of SSC on operative time and blood loss in primary cesarean births for breech presentation. METHODS: A SSC protocol for cesarean birth was implemented in our institution on February 25, 2019. In this single-center retrospective cohort study, we compared the outcomes of planned primary cesarean births for breech presentation at term before and after its implementation. RESULTS: Data from 110 women who had a cesarean birth for breech presentation at term were analyzed, 55 in each group. Group 1 were women who had immediate SSC and Group 2 were women without immediate SSC. Maternal and surgical characteristics, and neonatal outcomes were similar in both groups. The mean operative time was 3.22 minutes shorter in the immediate SSC group compared with the not immediate SSC group (37.13 ± 12.27 vs 40.35 ± 12.23 minutes; P = 0.171). CONCLUSIONS: In conclusion, immediate SSC following a low-risk cesarean birth for breech presentation neither prolongs the operative time nor increases blood loss during the procedure. Although we were unable to demonstrate a significant reduction in the operative time with the immediate SSC protocol, a decrease of 3 minutes was noted.

Metabolomics of Escherichia coli for Disclosing Novel Metabolic Engineering Strategies for Enhancing Hydrogen and Ethanol Production.

The biological production of hydrogen is an appealing approach to mitigating the environmental problems caused by the diminishing supply of fossil fuels and the need for greener energy. Escherichia coli is one of the best-characterized microorganisms capable of consuming glycerol-a waste product of the biodiesel industry-and producing H2 and ethanol. However, the natural capacity of E. coli to generate these compounds is insufficient for commercial or industrial purposes. Metabolic engineering allows for the rewiring of the carbon source towards H2 production, although the strategies for achieving this aim are difficult to foresee. In this work, we use metabolomics platforms through GC-MS and FT-IR techniques to detect metabolic bottlenecks in the engineered ΔldhΔgndΔfrdBC::kan (M4) and ΔldhΔgndΔfrdBCΔtdcE::kan (M5) E. coli strains, previously reported as improved H2 and ethanol producers. In the M5 strain, increased intracellular citrate and malate were detected by GC-MS. These metabolites can be redirected towards acetyl-CoA and formate by the overexpression of the citrate lyase (CIT) enzyme and by co-overexpressing the anaplerotic human phosphoenol pyruvate carboxykinase (hPEPCK) or malic (MaeA) enzymes using inducible promoter vectors. These strategies enhanced specific H2 production by up to 1.25- and 1.49-fold, respectively, compared to the reference strains. Other parameters, such as ethanol and H2 yields, were also enhanced. However, these vectors may provoke metabolic burden in anaerobic conditions. Therefore, alternative strategies for a tighter control of protein expression should be addressed in order to avoid undesirable effects in the metabolic network.

Cytomegalovirus in the transplant setting: Where are we now and what happens next? A report from the International CMV Symposium 2021.

The CMV Symposium in September 2021 was an international conference dedicated to cytomegalovirus (CMV) infection after solid organ or hematopoietic stem cell transplantation. This review provides an overview of the presentations given by the expert faculty, supplemented with educational clinical cases. Topics discussed include CMV epidemiology and diagnosis, the burden of CMV infection and disease, CMV-specific immunity and management of CMV in transplant settings. Major advances in the prevention and treatment of CMV in the past decade and increased understanding of CMV immunity have led to improved patient outcomes. In the future, management algorithms may be individualized based on the transplant recipient's immune profile, which will mark the start of a new era for patients with CMV.

Gestational age-based reference ranges for cervical length and preterm birth prediction in triplet pregnancies: an observational retrospective study.

OBJECTIVES: To develop gestational age-based reference ranges for cervical length in triplet pregnancies. The secondary objective was to assess the performance of cervical length measured between 18 and 20 + 6 days for the prediction of preterm delivery before 28 and 32 weeks, respectively. METHODS: Observational retrospective study of triplet pregnancies in three Spanish tertiary-care hospitals between 2001 and 2019. Cervical length measurements were consecutively obtained between 15 and 34 weeks of gestation. Pregnancies undergoing multifetal reduction or fetal surgery were excluded. RESULTS: Two hundred and six triplet pregnancies were included in the final analysis. There was a quadratic decrease in cervical length with gestational age. The median and fifth centiles for cervical length at 20 weeks were 35 and 13 mm. In the prediction of preterm birth < 28 weeks, for a false positive rate of 5%, and 10%, the detection rates were 40.9%, and 40.9%, respectively, and the prediction of preterm birth < 32 weeks, 22.0% and 26.0%, respectively. CONCLUSIONS: In triplet pregnancies, cervical length decreases with gestational age. The performance of cervical length at 18-20 + 6 in screening for preterm birth before 28 and 32 weeks is poor.

Early vaginal progesterone versus placebo in twin pregnancies for the prevention of spontaneous preterm birth: a randomized, double-blind trial.

BACKGROUND: In women with a singleton pregnancy and sonographic short cervix in midgestation, vaginal administration of progesterone reduces the risk of early preterm birth and improves neonatal outcomes without any demonstrable deleterious effects on childhood neurodevelopment. In women with twin pregnancies, the rate of spontaneous early preterm birth is 10 times higher than that in singletons, and in this respect, all twins are at an increased risk of preterm birth. However, 6 trials in unselected twin pregnancies reported that vaginal administration of progesterone from midgestation had no significant effect on the incidence of early preterm birth. Such apparent lack of effectiveness of progesterone in twins may be due to inadequate dosage or treatment that is started too late in pregnancy. OBJECTIVE: The early vaginal progesterone for the prevention of spontaneous preterm birth in twins, a randomized, placebo-controlled, double-blind trial, was designed to test the hypothesis that among women with twin pregnancies, vaginal progesterone at a dose of 600 mg per day from 11 to 14 until 34 weeks' gestation, as compared with placebo, would result in a significant reduction in the incidence of spontaneous preterm birth between 24+0 and 33+6 weeks. STUDY DESIGN: The trial was conducted at 22 hospitals in England, Spain, Bulgaria, Italy, Belgium, and France. Women were randomly assigned in a 1:1 ratio to receive either progesterone or placebo, and in the random-sequence generation, there was stratification according to the participating center. The primary outcome was spontaneous birth between 24+0 and 33+6 weeks' gestation. Statistical analyses were performed on an intention-to-treat basis. Logistic regression analysis was used to determine the significance of difference in the incidence of spontaneous birth between 24+0 and 33+6 weeks' gestation between the progesterone and placebo groups, adjusting for the effect of participating center, chorionicity, parity, and method of conception. Prespecified tests of treatment interaction effects with chorionicity, parity, method of conception, compliance, and cervical length at recruitment were performed. A post hoc analysis using mixed-effects Cox regression was used for further exploration of the effect of progesterone on preterm birth. RESULTS: We recruited 1194 women between May 2017 and April 2019; 21 withdrew consent and 4 were lost to follow-up, which left 582 in the progesterone group and 587 in the placebo group. Adherence was good, with reported intake of ≥80% of the required number of capsules in 81.4% of the participants. After excluding births before 24 weeks and indicated deliveries before 34 weeks, spontaneous birth between 24+0 and 33+6 weeks occurred in 10.4% (56/541) of participants in the progesterone group and in 8.2% (44/538) in the placebo group (odds ratio in the progesterone group, adjusting for the effect of participating center, chorionicity, parity, and method of conception, 1.35; 95% confidence interval, 0.88-2.05; P=.17). There was no evidence of interaction between the effects of treatment and chorionicity (P=.28), parity (P=.35), method of conception (P=.56), and adherence (P=.34); however, there was weak evidence of an interaction with cervical length (P=.08) suggestive of harm to those with a cervical length of ≥30 mm (odds ratio, 1.61; 95% confidence interval, 1.01-2.59) and potential benefit for those with a cervical length of <30 mm (odds ratio, 0.56; 95% confidence interval, 0.20-1.60). There was no evidence of difference between the 2 treatment groups for stillbirth or neonatal death, neonatal complications, neonatal therapy, and poor fetal growth. In the progesterone group, 1.4% (8/582) of women and 1.9% (22/1164) of fetuses experienced at least 1 serious adverse event; the respective numbers for the placebo group were 1.2% (7/587) and 3.2% (37/1174) (P=.80 and P=.06, respectively). In the post hoc time-to-event analysis, miscarriage or spontaneous preterm birth between randomization and 31+6 weeks' gestation was reduced in the progesterone group relative to the placebo group (hazard ratio, 0.23; 95% confidence interval, 0.08-0.69). CONCLUSION: In women with twin pregnancies, universal treatment with vaginal progesterone did not reduce the incidence of spontaneous birth between 24+0 and 33+6 weeks' gestation. Post hoc time-to-event analysis led to the suggestion that progesterone may reduce the risk of spontaneous birth before 32 weeks' gestation in women with a cervical length of <30 mm, and it may increase the risk for those with a cervical length of ≥30 mm.

Spontaneous twin anemia-polycythemia sequence from two donors to one recipient in a monochorionic triamniotic pregnancy: Case report and review of the literature.

Monochorionic triamniotic (MCTA) pregnancies present a high number of complications, mainly due to the presence of unbalanced vascular anastomoses, such as twin anemia-polycythemia sequence (TAPS). Previous reported cases related to TAPS are in twin pregnancies or only affect the monochorionic component of dichorionic triamniotic (DCTA) pregnancies. We report an exceptional case, the only one reported as far as we know, of a MCTA pregnancy that developed a TAPS in which the three triplets are implicated, from two donors to one recipient. The pregnancy had been previously sonographically diagnosed as DCTA pregnancy and this could not explain the clinical results. The pathological study of the placenta showed the presence of three monochorionic dividing membranes, a congested area in the recipient parenchyma and two non-congested areas in the donor's parenchyma that confirmed the clinical findings. Pathological study of multiple placentas should always be done because it provides understanding of pregnancy complications.

Prenatal Diagnosis of Aortic Coarctation: Prediction Algorithm according to Gestational Age.

OBJECTIVES: The aim of the study was first to quantify the diagnostic accuracy of predictive anatomical factors of aortic coarctation (CoA) and second to design a postnatal CoA probability algorithm according to gestational age (GA) in prenatal period. METHODS: Global and according to GA diagnostic performance of cardiac anatomical variables using the ROC curve were evaluated in a retrospective cohort of fetuses with suspicion of CoA (2004-2020). A serial testing strategy to predict postnatal CoA by fetal echocardiography was designed. RESULTS: 114 fetuses were included. Isthmus-to-ductal (I/D) ratio provided the best discrimination between healthy fetuses and those with CoA (AUC 0.91, 95% CI: 0.86-0.96, I/D < 0.74 sensitivity 96.3%, I/D < 0.6, specificity 92.5%) with good classification capacity in both the second and third trimesters of gestation. Isthmus z-score and pulmonary/aortic valve ratio increased accuracy in fetuses >28 and tricuspid/mitral valve ratio (TV/MV) in fetuses ≤28 weeks. Study of I/D plus TV/MV ratio in fetuses ≤28 and I/D ratio plus isthmus z-scores in fetuses >28 weeks allowed to correctly classify 91.8% of fetuses as high or low probability of postnatal CoA. CONCLUSIONS: Diagnostic discrimination of anatomic predictive factors for CoA varies according to GA. Specific algorithms according to GA increase accuracy in CoA's prenatal prediction.

Gestational Age-Specific Reference Ranges for the sFlt-1/PlGF Immunoassay Ratio in Twin Pregnancies.

OBJECTIVE: Establish reference ranges for the Elecsys® soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) immunoassay ratio in twin pregnancies. METHODS: Data analyzed were from 3 prospective studies: Prediction of Short-Term Outcome in Pregnant Women with Suspected Preeclampsia (PE) (PROGNOSIS), Study of Early-onset PE in Spain (STEPS), and a multicenter case-control study. Median, 5th, and 95th percentiles for sFlt-1, PlGF, and the sFlt-1/PlGF ratios were determined for normal twin pregnancies for 7 gestational windows and compared with the previous data for singleton pregnancies. RESULTS: The reference range analysis included 269 women with normal twin pregnancies. Before 29 weeks' gestation, median, 5th, and 95th percentiles for sFlt-1/PlGF ratios did not differ between twin and singleton pregnancies. From 29 weeks' gestation to delivery, median, 5th, and 95th percentiles for sFlt-1/PlGF ratios were substantially higher in twin versus singleton pregnancies. sFlt-1 values were higher in women with twin pregnancies across all gestational windows. PlGF values were similar or higher in twin versus singleton pregnancies; PlGF concentrations increased from 10 weeks + 0 days to 28 weeks + 6 days' gestation. CONCLUSIONS: Reference ranges for the sFlt-1/PlGF ratio are similar in women with twin and singleton pregnancies until 29 weeks' gestation but appear higher in twin pregnancies thereafter.

Authentication of PDO paprika powder (Pimentón de la Vera) by multivariate analysis of the elemental fingerprint determined by ED-XRF. A feasibility study.

Products with a Protected Denomination of Origin (PDO) are vulnerable to misdescription of their true geographical origin. In this work a method has been developed that allows the authentication of La Vera paprika powder (Pimentón de la Vera), a PDO product from the central-west Spanish region, Extremadura. The mass fractions of Br, Ca, Cr, Cl, Cu, Fe, K, Mn, Ni, P, Rb, S, Sr and Zn determined by energy dispersive X-ray fluorescence (ED-XRF) are used for classification purposes by multivariate analysis using Soft Independent Modelling of Class Analogy (SIMCA) (PCA-Class) and Partial Least Square-Discriminant Analysis (PLS-DA). Sixty-seven paprika samples purchased in supermarkets around Europe and on-line via the official web-site of Pimentón de La Vera, were used to build up the models for prediction purposes. The PCA-class model of La Vera paprika powder had a sensitivity of 82%, a specificity of 100% and an accuracy of 91%, whereas the PLS-DA model had a sensitivity of 100%, a specificity of 91% and an accuracy of 96%.

Lupus miliaris disseminatus faciei with complete response to isotretinoin.

Lupus miliaris disseminatus faciei is an uncommon type of granulomatous rosacea characterized by a papular eruption in the central regions of the face. A 43-year-old woman presented with an asymptomatic papular eruption on the face that had developed over a period of five months. Physical examination revealed multiple, small, reddish-brown papules, distributed symmetrically on the central area of the face. A biopsy was taken, showing dermal epithelioid cell granulomas with central necrosis and surrounding lymphocytic infiltrate with multinucleate giant cells. No foreign bodies were found in granulomas and no mycobacterial or fungal components were detected. On the basis of these findings, the diagnosis of lupus miliaris disseminatus faciei was made. The patient was given oral isotretinoin 20mg/day with initial slow response. After 6 months' treatment the lesions completely disappeared. Many authors consider this entity to be a variant of granulomatous rosacea. It is a chronic condition that primarily affects young adults. Treatment is usually unsatisfactory. Therapies with corticosterois, tetracyclines, retinoids, clofazimine or topical tacrolimus have been described but there is a lack of controlled studies and convincing results. Our success with a 6-month course of low dose isotretinoin suggests consideration of a longer trial prior to abandoning this as treatment.

Male fetal sex is associated with low maternal plasma anti-inflammatory cytokine profile in the first trimester of healthy pregnancies.

Male fetal sex associates with higher rates of materno-fetal complications. Inflammation and inadequate vasoactive responses are mechanisms implicated in obstetric complications, and alterations in maternal plasma cytokine profile and nitric oxide (NO) metabolites are potential predictive biomarkers. We aimed to assess if these parameters are influenced by fetal sex. A prospective, observational study was carried out in 85 healthy pregnant women with singleton pregnancies in the first trimester of gestation. A blood sample was extracted at the tenth week of gestation. In plasma, we assessed: 1) cytokines (micro-array): pro-inflammatory (IL1α, IL1 ß, IL6, TNFα), anti-inflammatory (IL4, IL10, IL13), and chemoattractant (IL8, MCP1, IFNγ), and 2) NO metabolites (liquid chromatography-tandem mass spectrometry and Griess reaction): L-arginine, ADMA, SDMA, nitrates (NOx). Women with a male fetus (n = 50) exhibited, compared with those with a female (n = 35): higher IL1ß (OR = 1.09 with 95% CI: 0.97-1.28), and lower IL13 (OR = 0.93 with 95% CI: 0.87-0.99), and higher plasma NOx (OR = 1.14 with 95% CI: 1.03-1.31). Our data suggest that fetal sex influences maternal plasma cytokine profile and NO in early pregnancy. Women with a male fetus may have a worse capacity to counteract an inflammatory response. They may have better vasodilator capacity, but in the presence of an oxidative environment, a higher nitrosative damage may occur. These data reinforce the need to include sex as variable in predictive models.

Does the right ventricle experiment morphologic and functional changes similarly to the left ventricle during pregnancy?

OBJECTIVE: Morphological and functional right ventricular (RV) changes during normal pregnancy remain poorly characterized. Similar to left ventricle, RV load and function are expected to change, and establishing reference values for RV during a healthy pregnancy is critical for the evaluation of pregnancy-related heart disease. The aim of the study was to describe RV adaptation in a prospective cohort. METHODS: Serial echocardiographic examinations were performed in second trimester (24 ± 2 weeks), third (32 ± 2 week) trimester, and postpartum (>3 months after delivery). Nulliparous women were evaluated as control group. RV linear dimensions, areas, and function were assessed and compared. RESULTS: Forty-three pregnant women were evaluated and compared with nineteen nulliparous women as control. Function parameters decreased along gestation. RV fractional area fell from second to third trimester (52.01 ± 0.92 vs 48.73 ± 0.97, P < .05), as well as tricuspid annular plane systolic excursion (2.62 ± 0.05 vs 2.41 ± 0.05, P < .05); however, RV longitudinal strain (L) decreased earlier, showing main changes from second trimester (26.17 ± 0.86 vs 22.71 ± 0.57, P < .003, control vs second trimester). S'-wave velocity followed a different pattern without changes during pregnancy. RV diameters significantly increased during pregnancy: basal (3.65 ± 0.06 vs 3.90 ± 0.06, P < .05), mid- (2.70 ± 0.06 vs 3.00 ± 0.07, P < .05), longitudinal (6.90 ± 0.09 vs 7.32 ± 0.11, P < .05), and right ventricle outflow tract proximal diameter (3.20 ± 0.06 vs 3.44 ± 0.06, P < .05). RV areas also suffered early variation during pregnancy. In postpartum evaluation, all these changes were reversed. CONCLUSION: During pregnancy, RV experiments important variations. RV size increases, and its function decreases. Changes in LS were earlier compared with other function measures.

Optimization of the Biocatalysis for D-DIBOA Synthesis Using a Quick and Sensitive New Spectrophotometric Quantification Method.

D-DIBOA (4-hydroxy-(2H)-1,4-benzoxazin-3-(4H)-one) is an allelopathic-derived compound with interesting herbicidal, fungicidal, and insecticide properties whose production has been successfully achieved by biocatalysis using a genetically engineered Escherichia coli strain. However, improvement and scaling-up of this process are hampered by the current methodology for D-DIBOA quantification, which is based on high-performance liquid chromatographic (HPLC), a time-consuming technique that requires expensive equipment and the use of environmentally unsafe solvents. In this work, we established and validated a rapid, simple, and sensitive spectrophotometric method for the quantification of the D-DIBOA produced by whole-cell biocatalysis, with limits of detection and quantification of 0.0165 and 0.0501 µmol·mL-1 respectively. This analysis takes place in only a few seconds and can be carried out using 100 µL of the sample in a microtiter plate reader. We performed several whole-cell biocatalysis strategies to optimize the process by monitoring D-DIBOA production every hour to keep control of both precursor and D-DIBOA concentrations in the bioreactor. These experiments allowed increasing the D-DIBOA production from the previously reported 5.01 mM up to 7.17 mM (43% increase). This methodology will facilitate processes such as the optimization of the biocatalyst, the scaling up, and the downstream purification.

A genetically engineered Escherichia coli strain overexpressing the nitroreductase NfsB is capable of producing the herbicide D-DIBOA with 100% molar yield.

BACKGROUND: The use of chemical herbicides has helped to improve agricultural production, although its intensive use has led to environmental damages. Plant allelochemicals are interesting alternatives due to their diversity and degradability in the environment. However, the main drawback of this option is their low natural production, which could be overcome by its chemical synthesis. In the case of the allelochemical DIBOA ((2,4-dihydroxy-2H)-1,4-benzoxazin-3(4H)-one), the synthesis of the analogous compound D-DIBOA (2-deoxy-DIBOA) has been achieved in two steps. However, the scale up of this synthesis is hindered by the second step, which uses an expensive catalyst and is an exothermic reaction, with hydrogen release and a relatively low molar yield (70%). We have previously explored the "Green Chemistry" alternative of using E. coli strains overexpressing the nitroreductase NfsB as a whole-cell-biocatalyst to replace this second step, although the molar yield in this case was lower than that of the chemical synthesis. RESULTS: In this work, we engineered an E. coli strain capable of carrying out this reaction with 100% molar yield and reaching a D-DIBOA concentration up to 379% respect to the highest biotransformation yield previously reported. This was achieved by a screening of 34 E. coli mutant strains in order to improve D-DIBOA production that led to the construction of the ΔlapAΔfliQ double mutant as an optimum genetic background for overexpression of the NfsB enzyme and D-DIBOA synthesis. Also, the use of a defined medium instead of a complex one, the optimization of the culture conditions and the development of processes with several substrate loads allowed obtaining maxima yields and concentrations. CONCLUSIONS: The high yields and concentrations of D-DIBOA reached by the microbial-cell-factory approach developed in this work will facilitate its application to industrial scale. Also, the use of an optimized defined medium with only an organic molecule (glucose as carbon and energy source) in its composition will also facilitate the downstream processes.

Cervical pessary to prevent preterm birth in women with twin gestation and sonographic short cervix: a multicenter randomized controlled trial (PECEP-Twins).

BACKGROUND: Spontaneous preterm birth (SPB) is the leading cause of perinatal morbidity and mortality. In twins, the rate of preterm birth is higher than in singletons; interventions to prevent preterm birth are needed in this high-risk population. OBJECTIVE: We sought to test whether a cervical pessary reduces the preterm birth rate in twin pregnancies with sonographic short cervix. STUDY DESIGN: A prospective, open-label, multicenter, randomized clinical trial was conducted in 5 hospitals in Spain. The ethics committees of all participating hospitals approved the protocol. The trial was registered as ClinicalTrials.gov, number NCT01242410. Eligible women were scanned in Spain. The primary outcome was SPB <34 weeks of gestation. Neonatal morbidity and mortality were also evaluated. RESULTS: Cervical length was measured in 2287 women; 137 pregnant women with a sonographic cervical length ≤25 mm (of 154 detected with a short cervix) were randomly assigned to receive a cervical pessary or expectant management (1:1 ratio). SPB <34 weeks of gestation was significantly less frequent in the pessary group than in the expectant management group (11/68 [16.2%] vs 26/66 [39.4%]; relative risk, 0.41; 95% confidence interval, 0.22-0.76). Pessary use was associated with a significant reduction in the rate of birthweight <2500 g (P = .01). No significant differences were observed in composite neonatal morbidity outcome (8/136 [5.9%] vs 12/130 [9.1%]; relative risk, 0.64; 95% confidence interval, 0.27-1.50) or neonatal mortality (none) between the groups. No serious adverse effects associated with the use of a cervical pessary were observed. CONCLUSION: The insertion of a cervical pessary was associated with a significant reduction in the SPB rate. We propose the use of a cervical pessary for preventing preterm birth in twin pregnancies of mothers with a short cervix.

Monozygotic Monochorionic Twins Discordant for Trisomy 21: A Reason to Evaluate Both Fetuses: A Case Report.

BACKGROUND: The occurrence of a discordant chromosomal abnormality in monozygotic twins is an extremely rare condition. CASE: We report the prenatal sonographic findings and cytogenetic studies in a monochorionic twin pregnancy discordant for severe fetal anomalies. Amniocentesis was normal for both twins. The pregnancy was managed conservatively, resulting in the delivery of discordant twins at 28 weeks. Cytogenetic analysis performed on cultured lymphocytes from peripheral blood revealed a mosaic 47XY+21 (in 2% of the cells)/46XY (in 98%) in the structurally normal twin, and a mosaic 47XY+21 (4%)/46XY (96%) for the abnormal twin. The abnormal neonate died shortly after delivery. The structurally normal twin survived without sequelae and had a normal karyotype 2 years later. CONCLUSION: This report adds to the literature a case of a monochorionic twin pregnancy with a mosaic fetus who gives his co-twin trisomic cells through placental vascular anastomoses, this twin being a chimera, highlighting the necessity of performing molecular genetics with polymorphic DNA markers to differentiate chimerism from mosaicism and define the origin of cell lines.

IMEP-115: determination of methylmercury in seafood by elemental mercury analysis: collaborative study.

A collaborative study IMEP-115 was organized by the European Union Reference Laboratory for Heavy Metals in Feed and Food (EURL-HM) to validate a method for the determination of methylmercury in seafood. The method was based on a liquid-liquid extraction with an organic solvent and with an aqueous cysteine solution. The final quantitation was done with an elemental mercury analyzer. Fifteen laboratories experienced in elemental mercury analyses, from 10 European countries, took part in the exercise. Five test items were selected to cover the concentration range from 0.013 to 5.12 mg/kg. All test items were reference materials certified for the methylmercury mass fraction: DOLT-4 (dogfish liver), TORT-2 (lobster hepatopancreas), SRM 2974a (mussel), SRM 1566b (oyster), and ERM CE-464 (tuna). Participants also received a bottle of ERM CE-463 (tuna) to test their analytical method before starting the collaborative study. Method validation showed adequate accuracy and acceptable precision for all test items, thus fitting its intended analytical purpose. The repeatability RSD ranged from 3.9 to 12.3%, while the reproducibility RSD ranged from 8.4 to 24.8%.