Greenhouse gas emissions and energy efficiencies for soybeans and maize cultivated in different agronomic zones: A case study of Argentina.

Of all human activities, agriculture has one of the highest environmental impacts, particularly related to Greenhouse Gas (GHG) emissions, energy use and land use change. Soybean and maize are two of the most commercialized agricultural commodities worldwide. Argentina contributes significantly to this trade, being the third major producer of soybeans, the first exporter of soymeal and soybean oil, and the third exporter of maize. Despite the economic importance of these crops and the products derived, there are very few studies regarding GHG emissions, energy use and efficiencies associated to Argentinean soybean and maize production. Therefore, the aim of this work is to determine the carbon and energy footprint, as well as the carbon and energy efficiencies, of soybeans and maize produced in Argentina, by analyzing 18 agronomic zones covering an agricultural area of 1.53millionkm2. Our results show that, for both crops, the GHG and energy efficiencies at the Pampean region were significantly higher than those at the extra-Pampean region. The national average for production of soybeans in Argentina results in 6.06ton/ton CO2-eq emitted to the atmosphere, while 0.887ton of soybean were produced per GJ of energy used; and for maize 5.01ton/ton CO2-eq emitted to the atmosphere and 0.740ton of maize were produced per each GJ of energy used. We found that the large differences on yields, GHGs and energy efficiencies between agronomic regions for soybean and maize crop production are mainly driven by climate, particularly mean annual precipitation. This study contributes for the first time to understand the carbon and energy footprint of soybean and maize production throughout several agronomic zones in Argentina. The significant differences found in the productive efficiencies questions on the environmental viability of expanding the agricultural frontier to less suitable lands for crop production.

[Comparison of two bedside tests performed on cervicovaginal fluid to diagnose premature rupture of membranes]. / Analyse comparative de deux tests diagnostiques de rupture prématurée des membranes dans les sécrétions cervico-vaginales.

OBJECTIVE: To compare the performance of two rapid tests for the diagnosis of premature rupture of membranes (PROM) based on the detection of the insulin-like growth factor-binding protein-1 (IGFBP-1) and placental α-microglobulin-1 (PAMG-1) in cervicovaginal secretions. METHODS: A case-control prospective study. Pregnant women between 24 and 41(6/7) weeks' of gestation, consulting for profuse amniotic fluid loss (group 1) or for other reasons without any rupture of membrane (group 2) were included in the study. Successively, AmniSure(®) test (PAMG-1) without speculum, and then Actim™Prom test (IGFBP-1) during speculum examination were performed during the same visit. RESULTS: Eighty subjects (40 in each group) were included between 25(1/7) to 41(1/7) weeks of gestation. AmniSure(®) diagnostic test demonstrated a sensitivity and specificity of 95 % (82.4-99.4) and 94.8 % (79.3-98) respectively and a positive and negative predictive value of 95 % (84.7-100) and 94.8 % (87.9-100) respectively. Actim™Prom diagnostic test demonstrated a sensitivity and specificity of 97.5 % (85.7-100) and 97.4 % (82.4-99.4) respectively and a positive and negative predictive value of 97.5 % (88.5-100) and 97.4 % (92.5-100) respectively. CONCLUSION: Both tests have similar performance to diagnose premature rupture of membranes.

Radiofrequency ablation of retained placenta accreta after conservative management: preliminary evaluation in the pregnant ewe and in normal human placenta in vitro.

OBJECTIVE: To evaluate radiofrequency (RF) efficiency and safety for the ablation of retained placenta in humans, using a pregnant sheep model. DESIGN: Experimental study. SETTING: Laboratory of Surgery School, Nancy, France. POPULATION/SAMPLE: Three pregnant ewes/ten human placentas. METHODS: Various RF procedures were tested in pregnant ewes on 50 placentomes (individual placental units). Reproducibility of the best procedure was then evaluated in a further 20 placentomes and on ten human term placentas in vitro after delivery. MAIN OUTCOME MEASURES: Placental tissues destruction, lesions' size, myometrial lesions. RESULTS: Low power (100 W) and low target temperatures (60 degrees C) lead to homogenous tissue destruction, without myometrial lesion. No significant difference was observed in terms of lesion size and procedure duration for in the placentomes of pregnant ewe in vivo and in human placentas in vitro. The diameter of the ablation could be correlated with the tines deployment. CONCLUSION: The placental tissue structure is very permissive to RF energy, which suggests that RF could be used for the ablation of retained placenta, providing optimal control of tissue destruction. These results call for further experimental evaluations.

First-trimester ultrasound diagnosis of skeletal dysplasia associated with increased nuchal translucency thickness.

A series of five cases of skeletal dysplasia is reported in which the diagnosis was reached at the 11-14-week routine ultrasound examination in our referral center. All five cases had increased nuchal translucency thickness (NT) associated with bone abnormalities. We review the current literature on skeletal dysplasia in the first trimester of pregnancy associated with increased NT.

Congenital erythropoietic porphyria (Günther's disease): two cases with very early prenatal manifestation and cystic hygroma.

Congenital erythropoietic porphyria (CEP) or Günther's disease is the rarest form of the porphyrias. The disease is usually diagnosed at birth or during early infancy, but rarely in utero. We describe here the first two cases of very early prenatal expression of CEP with cystic hygroma diagnosed at 14 weeks in the first fetus and at 19 weeks in the second. Both fetuses presented with severe nonimmune hydrops fetalis as early as 19 and 22 weeks, associated with intrauterine growth retardation, hyperechogenic kidneys and bones. Amniotic fluid was dark brown and uro- and coproporphyrin I was dramatically increased. Molecular screening of the CEP gene detected heterozygous C73R mutation in both fetuses, the other parental mutation being as yet unknown.

[Current clinical implications of transvaginal ultrasound measurement of the cervix during pregnancy]. / Implications cliniques actuelles de l'échographie du col utérin pendant la grossesse.

Transvaginal ultrasound measurement of the cervix is increasingly used for the prediction of preterm labor. In comparison to clinical vaginal examination, it has the advantages of being highly reproducible, with a low inter-observer variability, and of offering an evaluation of the entire cervical canal, including the internal os. The sensitivity and specificity of transvaginal ultrasound have been validated by several studies in women with symptoms of preterm labor, however its clinical applications and its limits have yet to be fully determined. It is likely to be of benefit in the management of multiple gestations, but it appears unlikely to be of use in low-risk pregnancies. Finally, whether it can be applied to estimate the risk of cervical incompetence, or to determine the need for cervical cerclage placement has not yet been determined by methodologically satisfactory clinical studies.

Is up-regulation of phosphodiesterase 4 activity by PGE2 involved in the desensitization of beta-mimetics in late pregnancy human myometrium?

Elevation of cAMP content resulting from stimulation of the receptor-adenylyl cyclase complex is involved in maintaining the quiescence of the human myometrium during pregnancy. The magnitude of this elevation is critically influenced by the rate of cAMP hydrolysis by phosphodiesterase (PDE) isoenzymes. In the present study we report that in term myometrium, enhanced cAMP-specific PDE4 activity takes part in the heterologous desensitization to the beta-mimetic, salbutamol. Indeed, pretreatment with a PDE4-selective inhibitor potentiates the relaxant effect of salbutamol on myometrial strips of women at term. Furthermore, the reduced relaxant effect of salbutamol after long-term treatment of myometrial strips with PGE2, a potent myometrial effector, can be reversed by PDE4 inhibition. Using a model of cultured myometrial cells, we also demonstrated that PGE2 is able to up-regulate PDE4 activity, at least through the induction of synthesis of PDE4B and PDE4D short forms, which, in turn, dampen the cAMP accumulation provoked by the stimulation of adenylyl cyclase. Such data suggest that in late pregnancy endogenous PGE2 might up-regulate PDE4 activity and lessen the responsiveness of myometrium to beta-mimetic activation. Accordingly, coapplication of a selective PDE4 inhibitor might greatly improve the usefulness of beta-mimetic in tocolysis.

Strip test for bedside detection of interleukin-6 in cervical secretions is predictive for impending preterm delivery.

Inflammatory cytokines in amniotic fluid are markers of prematurity which could characterize preterm labour of infectious origin. To avoid amniocentesis, we analyzed IL-6, IL-8, IL-10, and IL-13 by RT-PCR in cervical secretions (CS) of 307 women with preterm labour. IL-6 was detected in 26.3% patients who delivered at less than 34 weeks (specificity: 95.8%). In addition, IL-6 was associated with delivery within 7 days (specificity: 91.6%). To render the detection more rapid and cheaper, a strip test was designed and evaluated comparatively with RT-PCR in 76 women. This bedside strip test was twice more sensitive than RT-PCR, with little decrease in specificity.

EP(4) receptors mediate prostaglandin E(2)-stimulated glycosaminoglycan synthesis in human cervical fibroblasts in culture.

The aim of this study was to determine the prostaglandin E (EP) receptors and second messengers implicated in glycosaminoglycan (GAG) synthesis by human cervical fibroblasts in culture. Human cervical fibroblasts were obtained from cervical biopsies in pre-menopausal, cycling women. Cultured cells were incubated with prostaglandin E(2) (PGE(2)) and an array of agonists and antagonists. Glycosaminoglycan synthesis was assayed after extraction by measuring the [(3)H]glucosamine and [(35)S]sulphate incorporated into GAG and cAMP production was determined by radioimmunoassay. PGE(2) significantly stimulated GAG synthesis. Neither 17-phenyl-trinor-PGE(2), the EP(1) selective agonist, nor sulprostone, an EP(3) agonist, had any effect on GAG production. Butaprost, the EP(2) selective agonist, also failed to increase GAG synthesis. AH6809, an EP(2) antagonist, had no effect on PGE(2)-stimulated GAG production. AH23848, an EP(4) antagonist, inhibited the GAG synthesis provoked by PGE(2). PGE(2) and butaprost significantly increased cAMP production. Both AH6809 and AH23848 inhibited the PGE(2)-stimulated cAMP production. H89, a cAMP-dependent protein kinase (PKA) inhibitor, did not inhibit PGE(2)-stimulated GAG synthesis and Sp-cAMPS, a selective PKA activator, failed to increase GAG production. In conclusion, both EP(4) and EP(2) receptors are present and functional in human cervical fibroblasts. Only EP(4) receptors mediate PGE(2) stimulated GAG synthesis in a PKA-independent pathway.

Effects of progesterone on prostaglandin E(2)-induced changes in glycosaminoglycan synthesis by human cervical fibroblasts in culture.

Prostaglandins are known to induce cervical ripening and this effect may be mediated by an increase in glycosaminoglycan (GAG) concentration. The aim of this study was to assess the effects of progesterone on prostaglandin E(2) (PGE(2))-induced changes in GAG synthesis by human cervical cells in culture. Human cervical fibroblasts were obtained by cervical biopsies in hormonally active women and cultured. Cells were submitted to an incubation with progesterone or control medium. A second incubation was then performed with increasing concentrations of PGE(2). GAG synthesis by the cervical cells was assayed after extraction, by incorporation of [(3)H]-glucosamine and [(35)S]-sulphate into GAGs. It was found that progesterone alone induced a dose-dependent increase in GAG synthesis. After pre-incubation with progesterone, PGE(2) further increased [(3)H]-glucosamine and [(35)S]-sulphate uptake. However, when expressed as percentage of stimulation, the stimulatory effect of PGE(2) on GAG synthesis was inhibited at high progesterone concentrations. Therefore we concluded that, although high concentrations of progesterone increase the overall synthesis of GAG, they may also play a preventative role against PGE(2)-induced changes in GAG production during pregnancy.

High precursor level in maternal blood results from the alternate mode of proopiomelanocortin processing in human placenta.

OBJECTIVE: ACTH-producing non-pituitary tumours are often associated with altered precursor processing, particularly in the most aggressive ones. Since placental tissue is characterized by its ability to express the proopiomelanocortin (POMC) gene and rapid cellular proliferation, we examined whether intact POMC could be released physiologically during human gestation. SUBJECTS: One hundred and fifty six normal pregnant women, 12 with multiple pregnancies, and 23 non-pregnant controls. Twenty-eight women were studied in the immediate postpartum period. MEASUREMENTS: We measured plasma POMC levels with a specific immunoradiometric assay (IRMA) using a combination of antibodies directed against ACTH and beta endorphin. Results obtained with this first IRMA were confirmed in 22 subjects with a second assay using the same beta endorphin antibody and a more distal antibody directed against the N-terminal fragment of POMC. Reverse transcription-PCR detected full length, pituitary-like, POMC mRNA in human placenta. RESULTS: Plasma POMC was undetectable (< 60 U/ml) in 23 normal subjects. In normal monofetal pregnancies, POMC became detectable in most women by the third month and then increased steadily until midgestation: 168 +/- 108 (U/ml; mean +/- SD) between 12 and 15 weeks, 190 +/- 103 between 16 and 19 weeks, 324 +/- 180 between 20 and 23 weeks, 276 +/- 171 between 24 and 27 weeks, 292 +/- 177 between 28 and 31 weeks, 290 +/- 235 between 32 and 35 weeks and 308 +/- 210 between 36 weeks and parturition. Plasma POMC was significantly higher in multiple pregnancies with very high levels in three triplet-bearing mothers: 671, 941, and 1731 U/ml at 31, 33 and 32 weeks, respectively. POMC levels felt quickly in post partum, becoming undetectable in five of 13 women on day 1, seven of eight on day 2 and five of six on day 3. Plasma POMC displayed no diurnal variation, was not suppressed by glucocorticoid administration and did not correlate with plasma ACTH or cortisol. In contrast, plasma POMC positively correlated with plasma CRH. CONCLUSIONS: Pregnancy is the only condition in which POMC is produced and released physiologically, similar in some respects to the ectopic ACTH syndrome. POMC is derived solely from the placenta, with no interference from maternal pituitary secretion, and is thus a new and specific placental marker.

[Role of cervical modifications in threatened premature labor]. / Rôle des modifications du col utérin dans la menace d'accouchement prématuré.

Uterine cervical modifications play a central role in preterm labor and are one of the main indicators for the clinical diagnosis of this syndrome. Modifications of the cervix are either isolated events "cervical incompetence" or associated with cervicovaginal infection, which is an important etiological factor. Furthermore, the extent of cervical modifications in preterm labor is probably related to the prognosis of preterm delivery. Certain developments in the treatment of preterm pregnancy have focused on the uterine cervix (e.g. cervical cerclage, treatment of cervicovaginal infections) and such strategies may facilitate the prevention of preterm delivery. The information currently available emphasizes an independent role for the uterine cervix in preterm labor. As a consequence, it should be realised that even though there is a direct association between cervical modifications and uterine contractions, management of preterm labour must not be directed exclusively at the control of uterine contractions and tocolysis.

Effects of nomegestrol acetate on spontaneous and sulprostone-induced uterine contractions in pregnant cynomolgus monkeys monitored by telemetry.

OBJECTIVE: Our purpose was to study the effects of the progestomimetic compound nomegestrol acetate on spontaneous and sulprostone-induced uterine contractility in pregnant cynomolgus monkeys. STUDY DESIGN: Intrauterine pressure was continuously monitored with use of an implanted intraamniotic catheter and a telemetric pressure transmitter from day 115 to 135 of gestation (term = 165 days). After surgery the animals received either nomegestrol acetate (5 mg per day orally, n = 3) or vehicle only (controls, n = 3). The intramuscular prostaglandin E2 analog sulprostone (25 micrograms) was administered as a single injection 10 days after amniotic catheter implantation. Spontaneous and sulprostone-induced uterine contractions were compared between nomegestrol acetate- and vehicle-treated animals. RESULTS: The frequency of spontaneous uterine contractions in control animals demonstrated a 24-hour pattern with a minimum at 12 hours and a maximum at 0 hours. The frequency of spontaneous contractions did not differ between nomegestrol acetate- and vehicle-treated animals. Sulprostone induced an increase in both the frequency and amplitude of contractions, reaching a maximum 12 hours after injection and fading out after 24 hours in vehicle-treated animals. In animals receiving nomegestrol acetate, the frequency of contractions increased moderately and transiently for a total duration of 6 hours only and returned to control levels thereafter. CONCLUSION: Nomegestrol acetate significantly decreases the contractile response of the pregnant uterus induced by the prostaglandin E2 analog sulprostone.

Synthesis of glycosaminoglycans by human cervical fibroblasts in culture: effects of prostaglandin E2 and cyclic AMP.

OBJECTIVE: To study the mechanism of action of prostaglandin E2 (PGE2) and its analogue sulprostone leading to production of glycosaminoglycans (GAGs) in the human uterine cervix. STUDY DESIGN: We analysed the effects of PGE2 and its analogue sulprostone upon production of adenosine 3',5'-monophosphate (cAMP), in human cultured fibroblasts. We also studied the effects of PGE2, sulprostone and a cAMP analogue (8-Bromo-cAMP), on the incorporation of [3H]glucosamine into GAGs in human cervical fibroblasts in culture. RESULTS: Following treatment with PGE2 (10(-4)-10(-6) M), we observed a significant increase in the production of cAMP from 96.3 +/- 8.4 pmol/10(6) cells without phosphodiesterase inhibitor 3-isobutyl-methylxanthine (IBMX) to 325 +/- 63 pmol/10(6) cells with 10(-4) M IBMX (Spearman correlation test; P < 0.05). Under the same conditions, the effects of sulprostone (10(-6) M) were limited (from 8.1 +/- 1.5 to 51.3 +/- 14.1 pmol/10(6) cells without and with IBMX, respectively; not significant). Both PGE2 and 8-bromo-cAMP (from 10(-12) to 10(-4) M) increased [3H]glucosamine uptake into GAGs (Spearman correlation test; P < 0.05). Sulprostone (10(-12)-10(-4) M) was unable to reproduce such an effect even after a 24 or 48 h treatment. CONCLUSION: Since firstly, PGE2 acts through EP1, EP2 and EP3 specific receptors, whereas the action of sulprostone is only mediated by EP1 and EP3, and secondly EP2 receptor is coupled with cAMP production, we conclude that cAMP is involved in mediating the action of PGE2 upon GAG synthesis by human cultured cervical fibroblasts.

[Torsion of the pregnant uterus]. / Torsion de l'utérus gravide.

The authors report a case of 180 degrees torsion of the pregnant uterus. Torsion has been defined as a rotation of more than 45 degrees of the uterus around its long axis and is rare in humans. Clinical diagnosis is difficult since symptoms are either absent or non specific (cervical dystocia, painful uterine contractions, dynamic hypertonia...). Uterine torsion is often associated to pathologies of the uterus such as uterine myomas or congenital deformities, abnormal fetal presentations, pelvic tumours or abnormal pelvis. Maternal prognosis is good after surgical treatment, however, perinatal mortality remains high.

Relationship between mechanical properties of the uterine cervix and occurrence of postdate pregnancy.

Postmaturity is associated with an increased risk of fetal distress and of intrauterine fetal death. In order to assess the probability of the occurrence of postdate delivery, we have determined the Bishop score and measured the cervical distensibility index (CDI) using a cervicotonometer in 52 normal pregnant primiparous women between 37 and 40 weeks of pregnancy. 16 out of the 52 patients delivered after 41 weeks. Bishop scores and CDI were significantly lower in women who delivered after term than in those who delivered at or before 41 weeks (p less than 0.05; Student's test). The patients who had both a low Bishop score (less than or equal to 4) and a CDI less than 4 cm.kg-1 delivered after 41 weeks in 73% of the cases. Those who had a Bishop score less than or equal to 4 associated with a CDI greater than 4 cm.kg-1 delivered at or before 41 weeks in 80% of the cases. These results confirm the etiologic role of incomplete cervical maturation in postdate pregnancies. CDI measurement associated with the Bishop score could permit selection of the patients who would benefit from pharmacological cervical ripening.

Cyclooxygenase and lipoxygenase inhibitors--induced changes in the distribution of glycosaminoglycans in the pregnant rat uterine cervix.

In order to study the hormonal control mechanisms of cervical maturation, we investigated cyclooxygenase and 5-lipoxygenase inhibitors-induced changes in the distribution of glycosaminoglycans (GAG) in pregnant Wistar rat uterine cervices at term. The GAG were measured in a control (n = 11), in a Diclofenac (cyclooxygenase inhibitor) treated group (n = 8), in a BW 755C (dual inhibitor of cyclooxygenase and 5-lipoxygenase) treated group (n = 6), and a L 651392 (5-lipoxygenase inhibitor) treated group (n = 9). The results of these studies suggest, that cervical hyaluronic acid metabolism and cervical hydration are controlled in association by prostaglandins and leukotrienes (and perhaps by other phospholipids metabolites), whereas heparan sulphate metabolism is obviously controlled by prostaglandins. Nevertheless complete and normal cervical maturation is probably controlled in association by arachidonic acid metabolites and other factors (steroids and peptides).

Mechanical properties of the pregnant human uterine cervix use of an instrument to measure the index of cervical distensibility.

An instrument has been designed and manufactured to measure precisely in clinical practice the distensibility index of the human uterine cervix expressed as centimeters per kilogram. Operation of the instrument and possible errors measuring the cervical distensibility index in nonpregnant patients, during gestation and during the postpartum period, are presented. The ability to easily quantify the mechanical characteristics of the uterine cervix in humans throughout gestation will now allow one to carry out precise studies concerning pharmacologically induced cervical maturation or pathological modifications of the uterine cervix in cervical incompetence or threatened premature labor.