Alfredo M. Germain
Pontifical Catholic University of Chile
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Featured researches published by Alfredo M. Germain.
American Journal of Obstetrics and Gynecology | 1994
Alonso Rioseco; Milenko Ivankovic; Alejandro Manzur; Fuad Hamed; Sumie Kato; Julian T. Parer; Alfredo M. Germain
OBJECTIVES Intrahepatic cholestasis of pregnancy has been related to a high frequency of abnormal intrapartum fetal heart rate, amniotic fluid meconium, prematurity, and perinatal mortality. To determine whether these adverse perinatal outcomes could be improved with active intervention, we evaluated our results. STUDY DESIGN We report a retrospective case-control study of 320 consecutive patients with intrahepatic cholestasis of pregnancy management with antepartum testing and active intervention over a 2-year period. RESULTS Our results indicate a higher incidence of meconium staining in amniotic fluid at delivery (25% vs 16%, p < 0.05) and spontaneous preterm delivery (12.1% vs 3.9%, p < 0.05), without an increase in the frequency of abnormal intrapartum fetal heart rate (12% vs 11%, not significant), 5-minute Apgar score < 7 (2.0% vs 1.0%, not significant), or perinatal mortality (18/1000 vs 13/1000, not significant). CONCLUSION Antenatal testing and timed intervention of patients with intrahepatic cholestasis of pregnancy is associated with a reduction of the previously reported adverse perinatal outcomes.
Hypertension | 2007
Alfredo M. Germain; Mary Carmen Romanik; Irene Guerra; Sandra Solari; María Soledad Reyes; Richard J. Johnson; Karen L. Price; S. Ananth Karumanchi; Gloria Valdés
We tested the hypothesis that endothelial dysfunction could cause placentation-related defects, persist after the complicated pregnancy, and probably cause cardiovascular disease later in life. Brachial arterial reactivity and factors related to endothelial dysfunction, such as circulating cholesterol, uric acid, nitrites, l-arginine, asymmetrical dimethylarginine, vascular endothelial growth factor, and soluble vascular endothelial growth factor receptor-1, in women with previous healthy pregnancies (n=22), patients with severe preeclampsia (n=25), or patients with recurrent pregnancy loss (n=29), at day 10 of the luteal phase of an ovulatory cycle an average of 11 to 27 months after pregnancy were evaluated. Both groups with placentation defects had a significant decrease in endothelium-dependent dilatation, a higher rate of endothelial dysfunction, lower serum nitrites, and higher cholesterol as compared with control subjects; subjects with previous preeclampsia additionally had higher normal blood pressures and a greater parental prevalence of cardiovascular disease. Patients with recurrent pregnancy loss also demonstrated a significantly lower endothelium-independent vasodilatation. A trend to an inverse correlation was found between serum cholesterol serum and endothelial-mediated vasodilatation in the whole study population. Uric acid, l-arginine, asymmetrical dimethylarginine, vascular endothelial growth factor, and soluble vascular endothelial growth factor receptor-1 were similar in all of the groups. We postulate that endothelial dysfunction may represent a link between preeclampsia and increased cardiovascular disease latter in life and propose that women with unexplained recurrent miscarriages are also at increased cardiovascular risk. The identification and correction of endothelial dysfunction detected during the reproductive stage on obstetric outcome and on cardiovascular diseases needs to be elucidated.
Lipids | 2000
A. Cuevas; Viviana Guasch; Oscar Castillo; Verónica Irribarra; Claudio Mizon; Alejandra San Martin; Pablo Strobel; Druso Pérez; Alfredo M. Germain; Federico Leighton
Endothelial dysfunction is associated with atherogenesis and oxidative stress in humans. In rat and rabbit blood vessels, wine polyphenol antioxidants induce vascular relaxationin vitro through the NO-cGMP pathway. To assess the effect of a regular high-fat diet (HFD) and moderate red wine consumption on endothelial function (EF), a study was performed in healthy male volunteers. EF was measured as flow-mediated dilatation of the brachial artery, employing high-resolution ultrasound after an overnight fast. Other clinical and biochemical parameters related to EF were also measured. Six volunteers received a control diet, rich in fruits and vegetables (27% calories as fat) and five volunteers received an HFD (39.5% calories as fat). Measurements were done twice on each volunteer: after a period of 30 d with diet plus 240 mL of red wine/d, and after a period of 30 d with diet, without wine. In the absence of wine, there is a reduction of EF with HFD when compared to the control diet (P=0.014). This loss of EF is not seen when both diets are supplemented with wine for 30 d (P=0.001). Plasma levels ofn−3 fatty acids (R2=0.232,P=0.023) and lycopene (R2=0.223,P=0.020) show a positive correlation with individual EF measurements, but they do not account for the significant differences observed among dietary groups or after wine supplementation. These results help elucidate the deleterious effect of a high-fat diet and the protective role of wine, n−3 fatty acids and dietary antioxidants in cardiovascular disease.
Obstetrics & Gynecology | 2004
Héctor J. Lacassie; Alfredo M. Germain; Gloria Valdés; M. Soledad Fernandez; Francisco Allamand; Héctor Lopez
BACKGROUND: Eisenmenger syndrome in pregnancy may be a life-threatening disease despite recent additions to the treatment options. CASE: We present a woman with severe pulmonary hypertension due to Eisenmenger syndrome treated during pregnancy and delivery and postpartum with l-arginine and sildenafil to enhance the nitric oxide pathway. This combination was associated with significant improvement in the mothers clinical and hemodynamic condition and fetal well-being. CONCLUSION: The concomitant use of sildenafil and l-arginine for the management of pulmonary hypertension in pregnancy, combined with multidisciplinary care, permitted a good outcome for the mother and her infant.
Obstetrics & Gynecology | 1999
Alfredo M. Germain; Jorge Carvajal; Marta Sanchez; Guillermo Valenzuela; Harumi Tsunekawa; Benedicto Chuaqui
OBJECTIVE To determine the relevance of ischemia in the incidence of preterm labor. A second objective was to document perinatal outcomes for patients with preterm labor classified according to its clinical, functional, and pathologic characteristics (infectious, ischemic, mixed, or idiopathic). METHODS Perinatal outcomes were evaluated for 145 consecutive patients with preterm labor, subdivided into etiologic categories according to clinical, functional (Doppler), and morphologic (placental pathology) characteristics. A group of 44 normal pregnancies delivered at term served as controls. RESULTS Of the preterm labor group, 28.3% were classified as ischemic, compared with 4.5% of the control group (odds ratio and 95% confidence interval = 8.28 [1.8, 51.8]; P < .05). Compared with the control group, the preterm labor patients who delivered preterm had higher rates of ischemia (31.4% compared with 4.5%; P < .05) and infection (16.1% compared with 2.3%; P < .05). Among the preterm labor group, patients classified in the infectious or ischemic subgroups had a higher rate of preterm delivery (95.0% and 90.2% compared with 73.2%; P < .05), admission to the neonatal intensive care unit (75.0% and 61.0% compared with 40.0%; P < .05), and newborn weight under 1500 g (35.0% and 19.5% compared with 3.7%; P < .05) than the idiopathic subgroup. CONCLUSION Preterm labor resulting from infection or ischemia is associated with a higher perinatal complication rate than idiopathic preterm labor.
The Journal of Physiology | 2004
Claudia Torres-Farfan; Hans G. Richter; Alfredo M. Germain; Guillermo J. Valenzuela; Carmen Campino; Pedro Rojas-García; María Luisa Forcelledo; Fernando Torrealba; María Serón-Ferré
We tested the hypothesis that in primates, maternal melatonin restrains fetal and newborn adrenal cortisol production. A functional G‐protein‐coupled MT1 membrane‐bound melatonin receptor was detected in 90% gestation capuchin monkey fetal adrenals by (a) 2‐[125I] iodomelatonin binding (Kd, 75.7 ± 6.9 pm; Bmax, 2.6 ± 0.4 fmol (mg protein)−1), (b) cDNA identification, and (c) melatonin inhibition of adrenocorticotrophic hormone (ACTH)‐ and corticotrophin‐releasing hormone (CRH)‐stimulated cortisol but not of dehydroepiandrosterone sulphate (DHAS) production in vitro. Melatonin also inhibited ACTH‐induced 3β‐hydroxysteroid dehydrogenase mRNA expression. To assess the physiological relevance of these findings, we next studied the effect of chronic maternal melatonin suppression (induced by exposure to constant light during the last third of gestation) on maternal plasma oestradiol during gestation and on plasma cortisol concentration in the 4‐ to 6‐day‐old newborn. Constant light suppressed maternal melatonin without affecting maternal plasma oestradiol concentration, consistent with no effect on fetal DHAS, the precursor of maternal oestradiol. However, newborns from mothers under constant light condition had twice as much plasma cortisol as newborns from mothers maintained under a normal light–dark schedule. Newborns from mothers exposed to chronic constant light and daily melatonin replacement had normal plasma cortisol concentration. Our results support a role of maternal melatonin in fetal and neonatal primate cortisol regulation.
American Journal of Obstetrics and Gynecology | 2003
Alfredo M. Germain; Sumie Kato; Jorge Carvajal; Guillermo Valenzuela; Gloria Valdés; Juan Carlos Glasinovic
OBJECTIVE We tested the hypothesis that during intrahepatic cholestasis of pregnancy bile acids activate the myometrial oxytocin receptor pathway. STUDY DESIGN Myometrial sensitivity to oxytocin and oxytocin-receptor messenger RNA and protein level was investigated. The ability of cholic acid to mediate such changes was evaluated. RESULTS Cholestasis patients required lesser oxytocin to elicit four uterine contractions in 10 minutes (1.3+/-0.6 vs 3.6+/-0.8 U, P<.05, n=7) and had lower in vitro ED(50) (1.6 x 10(-10) mol/L vs 1.0 x 10(-8) mol/L, P<.05, n=7) than controls. The 24-hour incubation of control myometrial strips (n=7) with cholic acid (20 micromol/L) increased oxytocin sensitivity. Incubation of cultured myometrial cells (n=5) with cholic acid increased oxytocin-receptor expression (messenger RNA and protein). CONCLUSION We demonstrate that during intrahepatic cholestasis of pregnancy, an activation of the oxytocin receptor pathway occurs. This event seems to be the result of a cholic acid-mediated increase in oxytocin-receptor expression.
Endocrine | 2001
Gloria Valdés; Alfredo M. Germain; Jenny Corthorn; Cecilia Berrios; Arnaldo Foradori; Carlos M. Ferrario; K. Bridget Brosnihan
Since normal human pregnancy is characterized by normotension in the face of an increased renin-angiotensin-aldosterone system (RAAS), we evaluated the temporal pattern of urinary excretion of a novel vasodilator within this system, angiotensin-(1–7) (Ang-[1–7]), during the menstrual cycle, pregnancy, and lactation. The urinary profiles of Ang I, Ang II, human chorionic gonadotropin, 17β-estradiol, and progesterone were also determined. During the menstrual cycle, urinary Ang-(1–7) and Ang II remained stable (mean cycle value: 94.6±11.3 and 11.4±1.1 pmol/g of creatinine, respectively) in nine females. In 10 normal pregnant women, urinary Ang-(1–7) and Ang II increased throughout gestation, averaging 1499.8±310 and 224.4±58 pmol/g of creatinine, respectively (p<0.05) at wk 35 and falling during lactation to 394.0±95 and 65.7±20 pmol/g of creatinine (p<0.05), respectively. The Ang-(1–7)/Ang II ratio was unchanged in the different reproductive periods. During the menstrual cycle, Ang II and Ang-(1–7) correlated with 17β-estradiol and progesterone using multivariate analysis (r=0.31, p<0.001) and r=0.28, p<0.02, respectively). During gestation, 17β-estradiol and progesterone correlated with urinary Ang-(1–7) (r=0.48, p<0.001 and r=0.47, p<0.001, respectively) and Ang II (r=0.24, p<0.03 and r=0.25, p<0.03, respectively); by multiple regression, only Ang-(1–7) correlated with both steroids (r=0.49, p<0.001). The progressive rise of Ang-(1–7) throughout gestation, probably modulated by estrogen and progesterone, suggests a physiologic counterregulation within the RAAS.
Journal of The Society for Gynecologic Investigation | 2002
Alfredo M. Germain; Jorge Carvajal; Juan Carlos Glasinovic; C Sumie Kato; Catherine Williamson
Objective: To review animal and human data available regarding the etiology, maternal and fetal impact, and treatment of intrahepatic cholestasis of pregnancy (ICP). Methods: Pertinent studies on human and animal models of ICP were selected through a MEDLINE database search, focusing on etiology and clinical impact of the disease. Analytic and descriptive studies were included, and the data were analyzed looking for crude numbers. Results: Intrahepatic cholestasis of pregnancy is a pregnancy-specific disorder. Its prevalence is higher in Chile and Sweden compared with any other population. Its etiology is largely unknown, although endocrine, genetic, and environmental factors have been postulated as responsible for the appearance of the disease. Maternal effects of ICP are mild; however, there is a clear association between ICP and poor perinatal outcome, including a higher frequency of fetal distress, preterm labor and delivery, and unexplained fetal death. The treatment is mainly symptomatic. Recent data suggest that oral use of ursodeoxycholic acid improves maternal condition and might prevent the fetal complications of ICP. Conclusions: Intrahepatic cholestasis of pregnancy should be considered a high-risk condition, and careful fetal assessment and appropriate medical intervention might improve perinatal outcome.
Endocrine | 2001
Gloria Valdés; Alfredo M. Germain; Jenny Corthorn; Cecilia Chacón; Carlos D. Figueroa; Werner Müller-Esterl
This study was addressed to evaluate the temporospatial pattern of key components of the kallikreinkinin system in human uterus in luteal phase (n=7), early pregnancy (isolated spontaneous abortions, n = 11; ectopic pregnancies, n=9), idiopathic preterm deliveries (n=5), and term gestations (n=12). Tissue kallikrein mRNA and protein and the type 2 bradykinin receptor (B2R) protein were expressed in luminal and glandular epithelium and in endothelial cells of stromal and myometrial blood vessels, while tissue kallikrein mRNA and B2R, but not tissue kallikrein protein, were observed in decidual cells and in arteriolar and myometrial muscle. A greater signal intensity for tissue kallikrein mRNA and protein and of B2R protein was observed in the early pregnancy samples. The sites and variations of the tissue kallikrein mRNA and protein and of the B2R protein in the human uterus and in fallopian tubes during the luteal phase and in pregnancy coincide with those described for other vasoactive effectors such as nitric oxide, prostacyclins, growth factors, and renin. The uterine localization of the main enzyme and receptor of the tissue kallikrein-kinin system in key sites for embryo attachment, implantation, placentation, maintenance of placental blood flow, and parturition supports the notion that the kallikrein-kinin system participates in these processes, probably through vasodilation, increased vasopermeability, enhanced matrix degradation, stimulation of cell proliferation, and myometrial contractility.