117,365 research outputs found
Increased L-citrulline/L-arginine plasma ratio in severe preeclampsia.
No full textTo evaluate nitric oxide (NO) production in patients with pregnancy-induced hypertension or preeclampsia and in controls.Four groups of pregnant women were included: 17 patients with pregnancy-induced hypertension, ten with mild or moderate preeclampsia, 17 with severe preeclampsia, and 44 normotensive women matched for weeks of gestation at blood sampling with the cases. Plasma levels of L-citrulline and L-arginine were measured by using high-performance liquid chromatography.The mean plasma levels of L-citrulline and the ratio of L-citrulline to L-arginine, which reflects NO production, were higher in women with severe preeclampsia than in controls, patients with pregnancy-induced hypertension, and patients with mild or moderate preeclampsia.Nitric oxide production is enhanced in severe preeclampsia, possibly as a compensatory phenomenon for the increased synthesis and release of vasoconstrictors and platelet-aggregating agents
Low-dose aspirin in prevention and treatment of intrauterine growth retardation and pregnancy-induced hypertension
No full textMeta-analysis of data from several controlled trials has shown that low-dose aspirin reduces the risk of pregnancy-induced hypertension (PIH) and intrauterine growth retardation (IUGR) in women at high risk of these disorders. We have assessed the efficacy of low-dose aspirin in women judged to be at moderate risk. Women were included on prophylactic criteria--age under 18 or over 40 years, mild or moderate chronic hypertension (diastolic pressure between 90 and 110 mm Hg), nephropathy with normal renal function and blood pressure, history of PIH or IUGR, and twin pregnancy--or therapeutic criteria--PIH or early signs of IUGR in current pregnancy. Eligible women were randomly assigned treatment with 50 mg aspirin daily until delivery (583) or no treatment (523); 18 and 46 women, respectively, were lost to follow-up. The groups were well matched for baseline characteristics. We found no differences between the no-treatment and aspirin groups in numbers of spontaneous (5 vs 2) or therapeutic (1 vs 2) abortions, stillbirths (14 vs 13), perinatal mortality (35.7 vs 28.6 per 1000 births), mean birthweight (2858 [SD 729] vs 2874 [795] g), proportion of infants with birthweights below the 10th centile (95 [18.3%] vs 117 [19.0%]), or births before 37 weeks' gestation (184 [35.6%] vs 209 [33.9%]). Nor did the groups differ in the frequency of PIH with or without proteinuria (51 [15.2%] vs 81 [19.3%]). There was no difference in mean birthweight between the treatment groups in separate analyses according to criteria for trial entry and week of gestation at randomisation. Our study gives little support to the notion that low-dose aspirin is beneficial in women at moderate risk of PIH or IUGR
Migraine is a risk factor for hypertensive disorders inpregnancy: a prospective cohort study.
No full textRisk factors for pregnancy-induced hypertension in women at high risk for the condition. Italian Study of Aspirin in Pregnancy Group
No full textTo analyze determinants of the risk of pregnancy-induced hypertension (PIH) with or without proteinuria, we compared characteristics of women enrolled in the Italian Study of Aspirin in Pregnancy who developed PIH and those who did not. A total of 756 women were included in the present analysis; of these, 132 women (17%) developed PIH during the trial. The risk of developing PIH tended to increase with maternal age: in comparison with women age 20-25 years, the odds ratio (OR) estimates of risk ratio were 3.5 [95% confidence interval (CI) = 1.6-7.1] in women age 26-30 years and 4.2 (95% CI = 1.9-8.8) in those age > 30 years. There was little relation between development of PIH and education. PIH risk increased according to nonpregnant body mass index; in comparison with women with Quetelet's index (kg per m2) 25-30 and > 30. Parous women were at decreased risk of PIH: in comparison with nulliparas, the ORs were 0.7 (95% CI = 0.4-1.0) and 0.5 (95% CI = 0.3-0.9), respectively, in women reporting 1 or > or = 2 births. There was no important relation between previous spontaneous or induced abortion and PIH risk
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effect of corticotropin-releasing factor-binding protein on prostaglandin release from cultured maternal decidua and on contractile activity of human myometrium in vitro
No full textHuman placenta and uterine tissues are sites of production and local action of corticotropin-releasing factor (CRF). The recent evidence that CRF-binding protein (CRF-BP), a protein that blocks CRF-induced pituitary ACTH release, is produced by placental tissues suggested the present study to investigate the effects of CRF-BP on prostaglandin release and contractile activity of myometrial strips. Primary cultures of decidual cells were prepared using tissue collected from healthy women undergoing cesarean delivery at term. Mechanical and enzymatic cell dispersions were carried out, and experiments were performed 24-28 h after cell plating. The prostaglandin E2 (PGE2) concentration in cultured medium was measured by RIA. Myometrial strips were obtained from the upper edge of the uterine incision during elective cesarean section at term. Dissected free of connective tissue, strips were mounted in a 30-mL two-chamber organ bath containing oxygenated Tyrode's buffer (37 C) and connected to a two-channel isometric smooth muscle transducer. Cultured decidual cells collected at term significantly increased the release of PGE2 in the presence of CRF (P < 0.01). The addition of CRF-BP did not significantly modify PGE2 release, but completely reversed the effect of CRF. When human myometrial strips were incubated in the presence of CRF and PGF2 alpha, a significant increase in contractile activity was observed (P < 0.01); preincubation with CRF-BP prevented the increased contractile activity induced by CRF. The present data show that CRF-BP is able to counteract the biological effect of CRF on human pregnancy endometrium and myometrium and suggest that CRF-BP may be a regulatory protein that plays a role in the local function of uterine tissues during pregnancy
Corticotropin-releasing hormone increases prostaglandin F2 alpha activity on human myometrium in vitro
No full textOBJECTIVE:
Our purpose was to study the capability of synthetic corticotropin-releasing hormone to directly stimulate human myometrium and to modulate the activity of prostaglandins F2 alpha and E2.
STUDY DESIGN:
Strips from human myometrium were obtained from 127 elective cesarean sections at term. The in vitro effect of human rat corticotropin-releasing hormone on myometrial contractility has been studied in resting myometrial strips mounted in a two-chamber bath for isolated organs. Stimuli (corticotropin-releasing hormone, prostaglandins F2 alpha and E2, and oxytocin) were administered as one single dose in the perfusion chamber. In each experiment one myometrial strip was used as a control.
RESULTS:
Corticotropin-releasing hormone significantly increases (p < 0.01) the myometrial response to prostaglandin F2 alpha. The hormone neither has a direct inotropic effect nor is it able to enhance the effect of prostaglandin E2 and oxytocin on myometrial strips.
CONCLUSION:
The positive effect of corticotropin-releasing hormone on the myometrial response to prostaglandin F2 alpha adds new support to the theory that placental corticotropins may modulate the onset of labor
Oxidative Stress in the Early Neonatal Period as a Possible Effect of BMI, Smoking Habits, and Level of Urbanization of the Mother
No full textIntroduction: Oxidative stress (OS) can play a negative role in perinatal outcomes, but the underlying pathophysiology remains mostly unknown. This is a cross sectional study aiming to evaluate how the living environment, combined with some important maternal risk factors (i.e., smoke, overweight), could influence OS and inflammation markers during pregnancy and in newborns. Methods: Mothers and newborns were recruited at the Sant’Anna Gynecological Hospital (Turin, Italy). Environmental and lifestyle information was obtained through a standardized questionnaire (PRAMS). OS and inflammation markers (Isoprostane, IL (interleukin)-1, and IL-6) were analyzed in urine samples. Results: Overall, 126 mother-newborn couples were recruited. Oxidative stress and inflammation levels of mothers and infants have been shown to be significantly associated with each other (Spearman p < 0.01). Active and passive tobacco smoke during pregnancy (Spearman p < 0.01 and < 0.02, respectively), traffic exposure (Spearman p < 0.02), and higher BMI (body mass index) (Spearman p < 0.05) shown a positive role in this relationship. Conclusions: Our preliminary findings suggest that neonatal OS and inflammation are positively influenced by the three maternal risk factors analyzed: Tobacco smoke exposure, high urbanization levels, and high BMI. Further analysis are mandatory to better understand the biological mechanisms underlying such relationships. Nevertheless, correct management and monitoring of these factors must be considered by preventive Public Health strategies, to improve maternal and neonatal health and outcomes
Square Dancing with the Stars to Enhance Dynamic Hirschman Linkages?
No full textIn this Presidential Address, the author takes the reader on a reconnaissance of his life and time as a regional scientist. He points out scenery he found scintillating along the way, hoping that some may pick up the banner and chew on a few of the ideas for a while. He suggests a revisit to Albert O. Hirschman’s notion of key sectors and more empirical analysis related to Marcus Berliant’s and Masahisa Fujita’s notion of knowledge creation and transfer.Presidential Address, San Antonio, Texas, March 29, 2014 (53rd Meetings of the Southern Regional Science Association
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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