Gut barrier-microbiota imbalances in early life lead to higher sensitivity to inflammation in a murine model of C-section delivery.

BACKGROUND: Most interactions between the host and its microbiota occur at the gut barrier, and primary colonizers are essential in the gut barrier maturation in the early life. The mother-offspring transmission of microorganisms is the most important factor influencing microbial colonization in mammals, and C-section delivery (CSD) is an important disruptive factor of this transfer. Recently, the deregulation of symbiotic host-microbe interactions in early life has been shown to alter the maturation of the immune system, predisposing the host to gut barrier dysfunction and inflammation. The main goal of this study is to decipher the role of the early-life gut microbiota-barrier alterations and its links with later-life risks of intestinal inflammation in a murine model of CSD. RESULTS: The higher sensitivity to chemically induced inflammation in CSD mice is related to excessive exposure to a too diverse microbiota too early in life. This early microbial stimulus has short-term consequences on the host homeostasis. It switches the pup's immune response to an inflammatory context and alters the epithelium structure and the mucus-producing cells, disrupting gut homeostasis. This presence of a too diverse microbiota in the very early life involves a disproportionate short-chain fatty acids ratio and an excessive antigen exposure across the vulnerable gut barrier in the first days of life, before the gut closure. Besides, as shown by microbiota transfer experiments, the microbiota is causal in the high sensitivity of CSD mice to chemical-induced colitis and in most of the phenotypical parameters found altered in early life. Finally, supplementation with lactobacilli, the main bacterial group impacted by CSD in mice, reverts the higher sensitivity to inflammation in ex-germ-free mice colonized by CSD pups' microbiota. CONCLUSIONS: Early-life gut microbiota-host crosstalk alterations related to CSD could be the linchpin behind the phenotypic effects that lead to increased susceptibility to an induced inflammation later in life in mice. Video Abstract.

Insights into the mechanism of electrocatalysis of the oxygen reduction reaction by a porphyrinic metal organic framework.

Metal Organic Frameworks (MOFs) have been recently proposed as promising electrocatalysts, yet the exact nature of the mechanisms in play has not been addressed in depth. By comparing the electrocatalytic activity of a MOF for the oxygen reduction reaction (ORR) and the corresponding molecular building units through electrochemical techniques, here, we investigate the nature of the catalytic sites, their redox states and the electron transfer pathways.

High-intensity interval training reduces abdominal fat mass in postmenopausal women with type 2 diabetes.

AIM: This study compared the effect of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) for 16 weeks on whole-body and abdominal fat mass (FM) in postmenopausal women with type 2 diabetes (T2D). METHODS: Seventeen women (69±1 years; BMI: 31±1kg.m-2) were randomly assigned to either a HIIT [60×(8s at 77-85% HRmax, 12s of active recovery)] or MICT (40min at 55-60% of their individual HRR) cycling program for 16 weeks, 2 days/week. Dual-energy X-ray absorptiometry was used to measure whole-body and regional FM content, including abdominal adiposity and visceral adipose tissue. Plasma cholesterol, HDL, LDL, triglycerides, glucose and HbA1c levels were measured. Levels of nutritional intake and physical activity were evaluated by 7-day self-reports. RESULTS: Dietary energy (caloric) intake, physical activity level and total body mass did not vary in either group from the beginning to the end of the training intervention. Overall, total FM decreased and total fat-free mass significantly increased over time (by around 2-3%). Total FM reduction at the end of the intervention was not significantly different between groups. However, significant loss of total abdominal (-8.3±2.2%) and visceral (-24.2±7.7%) FM was observed only with HIIT. Time effects were noted for HbA1c and total cholesterol/HDL ratio. CONCLUSION: With no concomitant caloric restriction, an HIIT program in postmenopausal women with T2D (twice a week for 16 weeks) appeared to be more effective for reducing central obesity than MICT, and could be proposed as an alternative exercise training program for this population.

[Lynch syndrome and risk of prostate cancer; review of the literature]. / Syndrome de Lynch et risque de cancer de la prostate; revue de la littérature.

INTRODUCTION: The association between Lynch syndrome and prostate cancer has been studied. Recent studies report an association between these two diseases. MATERIAL AND METHODS: Literature review based on PubMed search was performed using the following keywords: Lynch syndrome and prostate cancer. RESULTS: Eight articles analyzing cohorts of subjects carrying Lynch syndrome were analysed including 6786 patients with 175 cancers. Prostate cancers were more frequent with a standardized incidence ratio (SIR) from 0.93 (95% CI: 0.19-2.7) and 5.9 (95% CI 4.1-17.1) and occurs at a younger age than in the general population mainly for mutations in the MSH2 gene. CONCLUSION: Prostate cancer seem more frequent and occur earlier in individuals harboring a mutation in the MSH2 gene while it does not appear to be any difference compared to the general population for other mutations in Lynch syndrome.

A portable transfer chamber for electrochemical measurements on electrodes prepared in ultra-high vacuum.

This paper describes a versatile, light weight, and portable chamber dedicated to the transfer of electrodes from ultra-high vacuum (UHV) to atmospheric pressure and the liquid phase. This chamber can be connected to a liquid-phase reaction cell to perform electrochemical measurements and transfer back the electrode to the UHV environment. The experimental set-up can also be turned in order to make the electrode the bottom of the electrochemical cell. The validity and the efficiency of the experimental set-up were tested with a Pt(111) surface that provides unique electrochemical features in acidic sulphate-containing solution. This transfer chamber concept provides the surface science community with a new and versatile tool, complementary to existing systems, which allows fast electrolyte purging or electrochemical measurements under well-controlled mass transport conditions.

[Prediction of maternofetal infection in preterm premature rupture of membranes: serum maternal markers]. / Prédiction de l'infection maternofœtale en cas de rupture prématurée des membranes par les marqueurs sériques maternels.

Premature rupture of membranes is a common situation in obstetrics that links the amniotic cavity and the bacterial cervicovaginal flora. The main risk in case of preterm premature rupture of membranes is the occurrence of an amniochorial infection, which increases neonatal morbidity and mortality. One main purpose in cases of preterm premature rupture of membranes is to identify infection early to adapt the clinical care. Among the marker used in practice, CRP has a sensitivity between 56% and 86% and specificity between 55% and 82% for predicting clinical chorioamnionitis. These values are respectively 21% to 56% and 76% to 95% for the prediction of early neonatal infection. The white blood cell count, also used in routine, has a poor predictive value of clinical chorioamnionitis although a high specificity when the threshold is of 16 giga/l. Among the pro-inflammatory cytokines, interleukin-6 has been the most studied. Its predictive value for chorioamnionitis or neonatal infection is higher but its clinical usefulness is limited by the various threshold used in the studies and the lack of routine measure. Procalcitonin appears to have low predictive values for detecting amniochorial infection but has finally been little studied. Ways to improve prediction of infection in cases of premature rupture of membranes are either looking for new markers or the analysis of local markers (vaginal secretions and amniotic fluid).

In situ infrared (FTIR) study of the mechanism of the borohydride oxidation reaction.

Early reports stated that Au was a catalyst of choice for the BOR because it would yield a near complete faradaic efficiency. However, it has recently been suggested that gold could yield to some extent the heterogeneous hydrolysis of BH, therefore lowering the electron count per BH, especially at low potential. Actually, the blur will exist regarding the BOR mechanism on Au as long as no physical proof regarding the reaction intermediates is not put forward. In that frame, in situ physical techniques like FTIR exhibit some interest to study the BOR. Consequently, in situ infrared reflectance spectroscopy measurements (SPAIRS technique) have been performed in 1 M NaOH/1 M NaBH(4) on a gold electrode with the aim to detect the intermediate species. We monitored several bands in B-H (nu ∼ 1180, 1080 and 972 cm(-1)) and B-O bond regions (nu = 1325 and ∼1425 cm(-1)), which appear sequentially as a function of the electrode polarization. These absorption bands are assigned to BH(3), BH(2) and BO species. At the light of the experimental results, possible initial elementary steps of the BOR on gold electrode have been proposed and discussed according to the relevant literature data.

[Nifedipine or nicardipine in management of threatened preterm delivery: an observational population-based study]. / Utilisation de la nifédipine et de la nicardipine dans le traitement de la menace d'accouchement prématurée: données observationnelles en population.

OBJECTIVE: For the first line tocolysis, calcium channel blockers (CCB)--oral nifedipine (Adalate®) or intravenous nicardipine (Loxen®)--are frequently used in France. No study compared nifedipine and nicardipine in management of threatened preterm delivery. From data of a French observational study, we compared factors associated with the use of nifedipine and nicardipine. Efficacy and tolerance of the two treatments were also compared. METHODS: It was a secondary analysis of EVAPRIMA study, a practice survey describing management of threatened preterm delivery in 107 French maternity units. Only women who received calcium channel blockers in their first line tocolytic therapy were included. We studied obstetrical factors associated with the choice of nifedipine or nicardipine. We also analyzed factors associated with a delivery within seven days following admission using univariate and multivariate analysis. Adverse secondary effects were compared between women who received nifedipine or nicardipine. RESULTS: Three hundred and four women received calcium channel blockers for their first line tocolytic therapy, in 73 maternity units: 93 (30.6%) women received oral nifedipine and 211 (69.4%) intravenous nicardipine. The same CCB was always prescribed in 69 maternity units. Admission after in utero transfer was less frequent among women who received nifedipine (6.5% versus 17.1%, P=0.01). Premature rupture of the membranes was also less frequent among women who received nifedipine (4.3% versus 13.7%, P=0.02), in comparison with women who received nicardipine. Median duration between admission for threatened preterm labor and delivery was longer when nifedipine was used (44 days versus 36 days, P=0.04). After adjustment on obstetrical factors, the risk to have a delivery within 7 days following admission was not significantly different between nifedipine and nicardipine groups (adjusted OR=0.5 [0.2-1.2]). Among women who received nifedipine only two cases (2.1%) of adverse event were reported with only one case needing a switch of treatment. Thirteen (6.2%) cases of adverse event were reported among women who received nicardipine (P=0.16); in three cases it motivated a switch. However, due to bias and limits inherent in such studies, our results should be interpreted cautiously. CONCLUSION: Nicardipine is the first choice for French obstetricians in management of severe threatened preterm delivery. However, intravenous nicardipine does not increase gestational duration in comparison with oral nifedipine.

[Uterine cervical length measurement by endovaginal ultrasonography: Technique and main utilizations]. / Mesure de la longueur du col de l'utérus par voie endovaginale : technique et principales applications.

Cervical length measurement by transvaginal ultrasound is commonly used to assess the risk of preterm birth (PTB) and refine the clinical management in cases of preterm labor (PTL). The transvaginal route is considered to be the reference for the measurement of the uterine cervix. Cervical length measurement has a good diagnostic value irrespective of the clinical context or past history associated with an increased risk of PTB. In case of PTL, the measurement of the cervical length by ultrasonography allows to reduce the number of hospitalizations, and to focus on the women who really need a treatment. In case of twin pregnancy, systematic systematic measurement of cervical length at 20-25 weeks gestation is not recommended because of the lack of therapeutic applications. In cases of high risk of PTB (PTB history, conization, uterine exposure to DES, etc.), selecting a group at high risk for PTB by a systematic cervical length measurement at 20-25 weeks gestation could be useful to select women for whom treatment with progesterone would be most beneficial. In this group, a follow-up of the cervical length since 16 weeks gestation may also be useful to indicate a cerclage if the cervical length is less than 15mm. In the general population, cervical length measurement may be useful during the second trimester of pregnancy in so far as a treatment by progesterone in cases of short cervix (

[Preterm premature rupture of membranes: active or expectant management?]. / Rupture prématurée des membranes avant terme: attitude interventionniste ou expectative?

Preterm premature rupture of membranes (PPROM) occurs in 3% of pregnancies and is responsible for 30% of preterm births. The management is discussed between active and expectant management. French recommendations let open both possibilities. The risks described in the case of PPROM are those of prematurity, maternofetal infection, acute procidence of the umbilical cord and abruptio placentae. Before 32 weeks of gestation (WG) and even 34 WG, a prolongation of one week of gestational age significantly decreases neonatal mortality and morbidity. Therefore, most of the authors choose expectant management in case of PPROM. Between 34 and 37 WG, the risk of rare severe morbidity associated with prematurity has to be balanced with risks of an acute maternofetal infection and of abruptio placentae. Further randomized trials are required to choose a type of management with a sufficient level of evidence.

Management of threatened preterm delivery in France: a national practice survey (the EVAPRIMA study).

OBJECTIVES: To describe the management of threatened preterm delivery (TPD) in France 3 years after publication of the French guidelines and to analyse the factors of variation of the practices observed. DESIGN: Population-based study. SETTING: Representative sample of French maternity units. The study included 107 hospitals, accounting for 20% of all French maternity units. POPULATION: Women hospitalised for TPD during May 2005. METHODS: Cross-sectional national practice survey. RESULTS: Of the 734 admissions for TPD, 12.1% involved premature rupture of membranes and 12.9% were in utero transfers. Women admitted for TPD accounted for roughly 6% of all annual deliveries, regardless of the unit's level of care, and 42.4% of these women delivered preterm: none delivered before 32 weeks in level 1 maternity units, 11.6% in level 2 and 88.4% in level 3. Transvaginal cervical ultrasound was performed for 54.5% of the women with intact membranes. Tocolysis was administered in 87.1% of women with intact membranes, with 45.6% of such women receiving this intervention for longer than 48 hours. First-line tocolytics used were calcium channel blockers (53.7%), beta-agonists (34.7%) or atosiban (8.8%), but their distribution differed substantially according to level of care. Maintenance tocolysis was administered to 385 women (59.8%) with intact membranes. Of the women admitted before 34 weeks, 21.1% did not receive corticosteroids. CONCLUSIONS: Practices for the management of TPD vary widely and appear to depend on the level of care. Some practices appear less than optimal, especially those related to duration of tocolysis, maintenance tocolysis, antenatal corticosteroid and use of cervical ultrasound.

Selective use of sonographic cervical length measurement for predicting imminent preterm delivery in women with preterm labor and intact membranes.

OBJECTIVES: To determine, in a population of women with preterm labor and intact membranes, whether ultrasound cervical length measurement performed only in patients selected according to the Bishop score predicts imminent preterm delivery better than does systematic cervical length measurement in the entire population. METHODS: The Bishop score and sonographic cervical length were recorded prospectively in women with preterm labor between 24 and 34 completed weeks' gestation. Outcome measures were preterm delivery within 48 h and within 7 days. Predictive values were calculated for each marker separately and then in combination. RESULTS: Of the study population of 395 women, 17 (4.3%) and 32 (8.1%) delivered within 48 h and within 7 days, respectively, following inclusion. For delivery within 7 days, areas under the Bishop score (0.848) and sonographic cervical length (0.813) receiver-operating characteristics curves did not differ significantly. For the selective use of sonographic cervical length measurement in patients selected according to the Bishop score, the test was considered positive if the Bishop score was >or= 8, or 4-7 with cervical length

In situ synchrotron far-infrared spectromicroscopy of a copper electrode at grazing incidence angle.

Synchrotron far-infrared spectroscopy in situ was successfully carried out on a copper microelectrode using a grazing-angle objective attached to a Bruker IRscope II microscope. The thin-layer spectroelectrochemical cell was constructed out of Teflon and fitted with a 20 microm-thick Mylar window; the copper electrode was 500 microm in diameter. Measurements were carried out in 0.1 M NaOH solution as a function of applied potential between -1.4 and 0 V versus a Hg/Hg2SO(4) reference electrode. Results demonstrate that with the present technique it is possible to obtain in situ spectra with excellent signal-to-noise ratio for surface oxide films formed electrochemically with less than 1 nL of active solution volume. The surface film on copper at 0 V consisted mainly of CuO with possibly some Cu(OH)2 also present. This interpretation is consistent with previous works and thermodynamic calculations.

Cervical assessment at 22 and 27 weeks for the prediction of spontaneous birth before 34 weeks in twin pregnancies: is transvaginal sonography more accurate than digital examination?

OBJECTIVES: This study compared the accuracy of ultrasound cervical assessment (cervical length and cervical index) and digital examination (Bishop score and cervical score) in the prediction of spontaneous birth before 34 weeks in twin pregnancies. METHODS: In a prospective multicenter study, digital examination and transvaginal sonography were performed consecutively in twin pregnancies attending for routine sonography at either 22 weeks (175 women) or 27 weeks (153 women). The digital examination took place first, and the Bishop score and cervical score (cervical length minus cervical dilatation) were calculated. Ultrasound measurements were then made of cervical length and funnel length to yield the cervical index (1 + funnel length/cervical length). The association between each variable and delivery before 34 weeks was tested by the Mann-Whitney U-test. The receiver-operating characteristics (ROC) curves of the ultrasound and digital indicators were determined for both gestational age periods, and the areas under the ROC curves compared. The best cut-off values for each indicator were used to determine predictive values for delivery before 34 weeks. RESULTS: The median gestational age at delivery among the women included in the 22-week examination period was 36.0 (range, 21-40) weeks; 10.9% (19) gave birth spontaneously before 34 weeks. The median cervical length was 40 (range, 6-65) mm. All four parameters were predictors of delivery before 34 weeks. The areas under the ROC curves for cervical index, cervical length, Bishop score and cervical score did not differ significantly. The median gestational age at delivery among the women in the 27-week examination period was 36.0 (range, 27-40) weeks; 9.2% (14) gave birth spontaneously before 34 weeks. The median cervical length was 35 (range, 1-57) mm. All parameters except the Bishop score were predictors of delivery before 34 weeks. The likelihood ratio of the positive and negative tests for cervical length < or = 25 mm was 5.4 (range, 3.2-9.0) and 0.3 (range, 0.1-0.7), respectively, compared with 2.3 (range, 1.3-4.2) and 0.6 (range, 0.3-1.1), respectively, for cervical score < or = 1. The area under the curve for the cervical index was significantly larger than that for the Bishop score (P = 0.008) or cervical score (P = 0.02). CONCLUSION: Transvaginal sonography predicted spontaneous delivery before 34 weeks better than digital examination at the 27-week but not the 22-week examination.

Ru-decorated Pt surfaces as model fuel cell electrocatalysts for CO electrooxidation.

This feature article concerns Pt surfaces modified (decorated) by ruthenium as model fuel cell electrocatalysts for electrooxidation processes. This work reveals the role of ruthenium promoters in enhancing electrocatalytic activity toward organic fuels for fuel cells, and it particularly concerns the methanol decomposition product, surface CO. A special focus is on surface mobility of the CO as it is catalytically oxidized to CO(2). Different methods used to prepare Ru-decorated Pt single crystal surfaces as well as Ru-decorated Pt nanoparticles are reviewed, and the methods of characterization and testing of their activity are discussed. The focus is on the origin of peak splitting involved in the voltammetric electrooxidation of CO on Ru-decorated Pt surfaces, and on the interpretative consequences of the splitting for single crystal and nanoparticle Pt/Ru bimetallic surfaces. Apparently, screening through the literature allows formulating several models of the CO stripping reaction, and the validity of these models is discussed. Major efforts are made in this article to compare the results reported by the Urbana-Champaign group and the Munich group, but also by other groups. As electrocatalysis is progressively more and more driven by theory, our review of the experimental findings may serve to summarize the state of the art and clarify the roads ahead. Future studies will deal with highly dispersed and reactive nanoscale surfaces and other more advanced catalytic materials for fuel cell catalysis and related energy applications. It is expected that the metal/metal and metal/substrate interactions will be increasingly investigated on atomic and electronic levels, with likewise increasing participation of theory, and the structure and reactivity of various monolayer catalytic systems involving more than two metals (that is ternary and quaternary systems) will be interrogated.

Interleukin-8 mRNA in vaginal secretions: a prenatal marker of congenital infection in case of preterm labor with intact membranes.

OBJECTIVE: To study whether interleukin-8 (IL-8) mRNA in vaginal secretions is associated with congenital infection and preterm delivery in the case of preterm labor with intact membranes. METHODS: This prospective clinical study in a tertiary referral center included 280 patients who gave birth to 360 infants from 1997 through 1999. IL-8 mRNA in vaginal secretions was determined with reverse transcriptase polymerase chain reaction. Logistic regression was used to examine the association between vaginal IL-8 mRNA and congenital infection independently of the time of birth. Main outcome measures were congenital infection and delivery before 37 and 33 weeks' gestation. RESULTS: A total of 100 women (100/280 (35.7%)) gave birth before 37 weeks. A total of 54 children (54/360 (15%)) had congenital infection. IL-8 mRNA in vaginal secretions was associated with delivery within 14 days of the sampling (24 (15.6%) vs. 7 (5.6%) p < 0.01), but not with delivery within 48 h, 7 days (p = 0.07) or before 37 or 33 weeks. There were more congenital infections in the group with detectable IL-8 mRNA (37 (19.3%) than in the negative group (17 (10.1%); p < 0.05). IL-8 mRNA was associated with congenital infection independently of the time of birth (OR: 2.6 (1.3-5.1)). This test had a sensitivity for predicting neonatal infection of 69%. Its specificity was 49%, its positive predictive value 19%, and its negative predictive value 90%. CONCLUSION: IL-8 mRNA could be a prenatal noninvasive vaginal marker of congenital infection.

Survival of very preterm infants: Epipage, a population based cohort study.

OBJECTIVE: To evaluate the outcome for all infants born before 33 weeks gestation until discharge from hospital. DESIGN: A prospective observational population based study. SETTING: Nine regions of France in 1997. PATIENTS: All births or late terminations of pregnancy for fetal or maternal reasons between 22 and 32 weeks gestation. MAIN OUTCOME MEASURE: Life status: stillbirth, live birth, death in delivery room, death in intensive care, decision to limit intensive care, survival to discharge. RESULTS: A total of 722 late terminations, 772 stillbirths, and 2901 live births were recorded. The incidence of very preterm births was 1.3 per 100 live births and stillbirths. The survival rate for births between 22 and 32 weeks was 67% of all births (including stillbirths), 85% of live births, and 89% of infants admitted to neonatal intensive care units. Survival increased with gestational age: 31% of all infants born alive at 24 weeks survived to discharge, 78% at 28 weeks, and 97% at 32 weeks. Survival among live births was lower for small for gestational age infants, multiple births, and boys. Overall, 50% of deaths after birth followed decisions to withhold or withdraw intensive care: 66% of deaths in the delivery room, decreasing with increasing gestational age; 44% of deaths in the neonatal intensive care unit, with little variation with gestational age. CONCLUSION: Among very preterm babies, chances of survival varies greatly according to the length of gestation. At all gestational ages, a large proportion of deaths are associated with a decision to limit intensive care.