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Biomedical subjects

R Romero

Publications and source records attributed to R Romero.

At least 289 records · Page 16Linked to original sources
PubMed1995

Fetal cytokine expression in utero detected by reverse transcriptase polymerase chain reaction.

Cytokine expression at the maternal-fetal interface is well documented. Some authors have postulated the existence of a bidirectional cytokine signaling mechanism that is critical to the maintenance of normal pregnancy. The role of the fetus (versus fetally derived placental tissues) in this process is unknown. Using reverse transcription polymerase chain reaction techniques, we studied paired maternal and fetal samples from 16 pregnancies (including two twin pregnancies) for the presence of tumor necrosis factor-alpha and IL-1 beta mRNA. We demonstrate that mRNA for both of these cytokines can be detected in both maternal and fetal blood as early as the 21st wk of gestation. These results support a potential role for the fetus in the bidirectional cytokine signaling of pregnancy.

Base Sequence↗
PubMed1995

Abnormal concentration of maternal serum activin-A in gestational diseases.

Serum plasma activin-A is measurable in the maternal circulation of healthy pregnant women, increases in specimens collected during the third trimester of gestation, and is highest at parturition. Hormone abnormalities are known to be associated with preterm labor or diabetes in pregnancy. Therefore, in the present study serum activin-A levels in normal controls were compared to those in pregnant women with preterm labor or gestational diabetes. In some cases, values were obtained before and after insulin therapy. In other controls and patients with preterm labor, the activin-A concentration in cord serum was also studied. A newly developed two-site immunotest was used to determine activin-A levels. Subjects included normal controls (n = 7), who were sampled throughout gestation every 5 weeks; pregnant women at term (38-40 weeks) not in labor (n = 22); pregnant women at term in spontaneous labor (< 3.0 cm dilated; n = 42); women in preterm labor (25-35 weeks; n = 38); and women with gestational diabetes (20-39 weeks; n = 9). In control women, serum activin-A levels increased from 4.8 +/- 5.5 micrograms/L (mean +/- SD) at 20 weeks to 25.4 +/- 27.8 micrograms/L at 40 weeks (P < 0.01), and values correlated with gestational age. Pregnant women in preterm labor had serum activin-A concentrations (89.04 +/- 173.31 micrograms/L) higher than those in normal controls (P < 0.01), and no significant correlation to gestational age was found in this group of pregnant women. Healthy women in labor showed serum activin-A concentrations higher than those in women at term but not in labor (P < 0.01). Diabetic patients had serum activin-A concentrations (52.39 +/- 23.32 micrograms/L) significantly higher than those in normal controls. In these patients, maternal serum activin-A concentrations significantly decreased to the range in healthy controls at the same gestational age after insulin therapy (9.48 +/- 3.82 micrograms/L). The present study shows that preterm labor is associated with increased concentrations of activin-A in the maternal circulation and cord serum. Hypersecretion of activin-A is also shown in same patients with gestation diabetes; this reverts to normal after insulin treatment.

Activins↗
PubMed1995

Doppler velocimetry of the fetal middle cerebral artery in patients with preterm labor and intact membranes.

A prospective cohort study was conducted to determine whether preterm labor is associated with changes in the impedance to blood flow of the fetal middle cerebral artery. Doppler velocimetry studies were performed in 194 consecutive patients with preterm labor and intact membranes. Pulsatility indices of the middle cerebral artery and umbilical artery were determined on admission. Results were expressed as ratio of the observed pulsatility index to mean value for gestational age expressed as delta MCA PI and delta UA PI, respectively. The prevalence of preterm delivery (< 37 weeks) and delivery within 24 hours of admission was 55.2% (107/194) and 15.5% (30/194), respectively. Patients with an examination-to-delivery interval within 24 hours had significantly lower mean delta MCA PI than that of patients delivered at > or = 37 weeks and > or = 4 weeks after the examination (P < 0.01). Fetuses with a delta MCA PI at or below 0.88 had a relative risk of 2 (95% confidence interval, 1.32 to 2.9) who were delivered within 24 hours compared to controls (sensitivity 76.7%, specificity 62.8%, positive predictive value 26.7%, negative predictive value 93.5%). Stepwise logistic regression analysis indicated that the relationship between delta MCA PI and examination-to-delivery interval remained statistically significant after correcting for cervical dilatation (P < 0.001). Our data indicate that preterm parturition is associated with a decrease in the impedance to flow in the fetal cerebral circulation.

Adult↗
PubMed1995

[Intra-amniotic infection, cytokines and premature labor].

This paper reviews the mechanisms leading to the commencement of labor in the presence of intrauterine infection. It is postulated that induction of preterm contractions represents an escape mechanism of the fetus from a hostile environment. Bacterial toxins provoke an immunological response (macrophages) of the fetomaternal compartment. Liberation of cytokines (IL-1, IL-6, IL-8) stimulates prostanoid synthesis in the decidua and amnion, as well as migration of granulocytes into the cervix. Additional still unknown factors may determine whether this process leads to cervical dilatation, effacement and finally preterm delivery. The role is discussed of other cytokines, i.e., colony-stimulating factors, transforming growth factor beta, and interleukin receptor antagonists as potential, clinically useful tocolytics in this labile equilibrium.

Bacterial Toxins↗
PubMed1995

Infection of the amniotic cavity with Ureaplasma urealyticum in the midtrimester of pregnancy.

The purpose of this study was to determine the clinical significance of invasion of the amniotic fluid (AF) with Ureaplasma urealyticum in the midtrimester of pregnancy. Amniotic fluid and cervical swabs obtained from 214 asymptomatic women in the midtrimester of pregnancy (16-20 weeks) were cultured for U urealyticum and Mycoplasma hominis. Inoculum size was determined by quantitative culture. Six of the 214 women (2.8%) had Ureaplasma in high titers in the AF. The pregnancy outcomes of 129 women were determined. Adverse pregnancy outcome occurred more frequently in women with a positive AF culture than in women with a negative AF culture (3/6 [50%] vs. 15/123 [12%], respectively; P = .035). We conclude that infection of the amniotic cavity with U urealyticum can be present in asymptomatic patients in the midtrimester of pregnancy and is a significant risk factor for spontaneous preterm labor and delivery. These observations suggest that routine culture of AF at the time of midtrimester amniocentesis can identify the group of patients at risk for a poor pregnancy outcome.

Abortion, Spontaneous↗
PubMed1995

Age as a determinant of glomerular filtration rate in non-insulin-dependent diabetes mellitus.

BACKGROUND: The level of glomerular filtration rate (GFR) and its determinants in non-insulin-dependent diabetes mellitus (NIDDM) are currently controversial. DESIGN OF THE STUDY: We measured GFR and effective renal plasma flow (ERPF) in 121 consecutive NIDDM without evidence of overt diabetic nephropathy. Age varied from 28 to 70 years, 61.2% were women and known duration of NIDDM was 0-37 years. Hypertension was detected in 36.4% of patients and 47.8% had microalbuminuria. RESULTS: An inverse correlation was found between GFR and age, but not with known duration of NIDDM: It was a weak correlation (r = -0.41) but statistically significant (P < 0.001). The other variables considered were not significant by multiple stepwise regression analysis, but patients with lower GFR tended to have diabetic retinopathy more frequently. GFR was lower in hypertensive compared to normotensive patients (123 +/- 28.4 versus 136 +/- 32.5 ml/min/1.73 m2; P < 0.05), but was not different between patients with normal and elevated albumin excretion rate. ERPF also had an inverse correlation with age (r = -0.45, P < 0.001). CONCLUSION: We conclude that (i) age should be considered as a confounding variable when evaluating GFR in patients with NIDDM, and (ii) the age-dependent decline in GFR may mask hyperfiltration in the early stages of diabetic nephropathy in NIDDM:

Adult↗
PubMed1995

Takayasu's arteritis as a cause of renovascular hypertension in a non-Asian population.

Takayasu's disease (TD) is a chronic inflammatory arteritis which affects the aorta and its main branches and occasionally the pulmonary artery. Its cause is not known. Clinical manifestations are due to the intensity and location of arterial inflammation in the acute phase, as well as chronic arterial stenosis over time; 50% of patients have hypertension. Although TD appears to be more common in Asia, increasing numbers of patients of different races are observed in Western countries. The most important pathogenetic mechanism of hypertension seems to be through renal artery stenosis. We show here seven Caucasian hypertensive patients with TD and renovascular stenosis and arterial hypertension. One case was diagnosed in the acute phase of the disease, while in the others diagnosis was established in an advanced occlusive phase. Basic diagnosis was established by angiographic study, with biopsy confirmation in two cases. All patients had at least three of the six criteria listed as diagnostic of TD (by the American College of Reumatology). All patients had the following criteria: age of disease onset before 40 years (symptoms or findings related to TD), vascular bruits in different areas and all patients also had aortic and renal arterial stenosis with some lesions of the main aortic branches. Six of them had claudication of the extremities. We describe their clinical, analytical and angiographic features and also the therapeutic approach. We discuss the aetiopathogenic mechanisms of hypertension in this disease and suggest that TD is not an unusual cause of vasculorenal hypertension.

Adult↗
PubMed1995

[Exercise physiology and the rehabilitation of the heart transplant patient].

Cardiac transplantation has succeeded in improving the survival of the patients with terminal heart failure spectacularly. Nevertheless, in the transplant recipients the cardiac response to the effort is limited. In order to increase the cardiac output, the denervated heart needs an important increase of the precharge, since its chronotropic response is reduced. This rise of the precharge, in a restrictive heart in itself, leads to a disproportionate increase of the filling pressures. This limits the functional capacity of the patient due to the feeling of dyspnea. A program of cardiac rehabilitation, that includes a physical continued training, gets to improve the physiopathologic response to the exercise of the transplant heart.

Exercise↗
PubMed1994

Is oligohydramnios a risk factor for infection in term premature rupture of membranes?

Our objective was to determine if a reduced volume of amniotic fluid is a risk factor for microbial invasion of the amniotic cavity in women with rupture of membranes at term. Transabdominal amniocentesis under ultrasound guidance was used to evaluate the microbiological state of the amniotic cavity in 53 patients with term premature rupture of membranes before vaginal examination. Amniotic fluid index was measured prior to the procedure in all cases. The prevalence of microbial invasion of the amniotic cavity was 32.1% (17/53). Women with microbial invasion of the amniotic cavity had a significantly lower median amniotic fluid index than did women without evidence of infection (median 4.4 cm, range 1.0-8.1 vs. median 7.8 cm, range 1.3-14.4, respectively; p < 0.001). An amniotic fluid index of < 5 cm had a sensitivity of 71% (12/17) a specificity of 89% (32/36), a positive predictive value of 75% (12/16) and a negative predictive value of 87% (32/37) in the prediction of microbial invasion of the amniotic cavity. Among women who delivered vaginally, those with an amniotic fluid index of < 5 cm had a higher rate of endometritis than those with an amniotic fluid index of >or= 5 cm (19% (3/16) vs. 0% (0/26), respectively; p < 0.05). We conclude that women with term premature rupture of membranes and an amniotic fluid index of < 5 cm are at an increased risk for microbial invasion of the amniotic cavity and puerperal infection after a vaginal delivery.

Journal Article↗
PubMed1994

Prenatal diagnosis of umbilical cord pseudocyst.

The association between umbilical cord anomalies and chromosomal abnormalities has received little attention in the literature. In this report, we present two cases of umbilical cord pseudocyst incidentally detected by ultrasound prior to genetic amniocentesis performed for the indication of advanced maternal age. In the first case it was only the initial abnormal finding in a 21-week fetus ultimately found to have a trisomy 18. In the second case, detected at 26 weeks, the karyotype was normal and a healthy normal neonate was delivered at term. The finding of a umbilical cord cystic mass during prenatal sonographic examination should alert the clinician to the increased risk of aneuploidy.

Journal Article↗
PubMed1994

Ultrasonographic examination of the uterine cervix is better than cervical digital examination as a predictor of the likelihood of premature delivery in patients with preterm labor and intact membranes.

OBJECTIVE: The purpose of this study was to compare the diagnostic performance of ultrasonographic and digital examination of the cervix in the prediction of preterm delivery in patients presenting with preterm labor and intact membranes. STUDY DESIGN: Endovaginal ultrasonography was performed in 59 patients admitted with preterm labor (20 to 35 weeks) and cervical dilatation of < 3 cm. Cervical parameters evaluated included endocervical length, the presence of funneling, funnel length, funnel width, cervical index ([Funnel length + 1]/Endocervical length), and cervical dilatation and effacement as determined by digital examination. Outcome variables were the occurrence of preterm delivery (< 36 weeks) and the admission-to-delivery interval. RESULTS: The prevalence of preterm delivery was 37.3% (22/59). Receiver-operator characteristic curve and logistic regression analyses indicated a significant relationship between the occurrence of preterm delivery and ultrasonographic cervical parameters (p < 0.005 for each) but not with the results of digital examination of the cervix. Survival analysis demonstrated a shorter admission-to-delivery interval for patients with an abnormal cervical index or endocervical length (p < 0.005 for each). CONCLUSIONS: Endovaginal ultrasonographic examination of the uterine cervix is more accurate than digital examination of the cervix in the assessment of the risk for preterm delivery in patients with preterm labor and intact membranes.

Biometry↗