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S Ballas

Publications and source records attributed to S Ballas.

At least 19 recordsLinked to original sources
PubMed2004

Association of T-786C eNOS gene polymorphism with increased susceptibility to acute chest syndrome in females with sickle cell disease.

Acute chest syndrome (ACS) is a life-threatening complication of sickle cell disease (SCD). A retrospective study was performed to evaluate the role of endothelial nitric oxide synthase (eNOS) gene polymorphisms (E298D and T-786C) in African-American SCD patients. The D298 allele showed no association; the C-786 allele showed a statistically significant association (P = 0.0061) in female ACS cases. Multiple logistic regression analysis showed that relative risk of ACS was 8.695 (P = 0.0076, 95% confidence interval 1.761-42.920) for female carriers of C-786. eNOS T-786C is a gender-specific genetic modifier that is associated with increased susceptibility to ACS in female SCD patients.

Acute Disease↗
PubMed2001

Purified poloxamer 188 for treatment of acute vaso-occlusive crisis of sickle cell disease: A randomized controlled trial.

CONTEXT: Sickle cell disease (SCD) can cause severe painful episodes that are often thought to be caused by vaso-occlusion. The current therapy for these uncomplicated painful episodes includes hydration, oxygen, and analgesics. Purified poloxamer 188 may increase tissue oxygenation and thereby reduce inflammation, pain, and the overall duration of such painful episodes in patients with SCD. OBJECTIVE: To compare the duration of painful episodes in patients with SCD treated with purified poloxamer 188 to that of similar episodes experienced by patients who receive a placebo. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled, intention-to-treat trial conducted between March 1998 and October 1999 in 40 medical centers in the United States. PARTICIPANTS: Two hundred fifty-five patients with SCD (aged 9-53 years) who had a painful episode sufficiently severe to require hospitalization and narcotic analgesics. INTERVENTION: Patients were randomly assigned to receive an intravenous infusion of purified poloxamer 188, 100 mg/kg for 1 hour followed by 30 mg/kg per hour for 47 hours (n = 127), or a matching volume of saline placebo (n = 128). MAIN OUTCOME MEASURE: Duration of the painful episode, from randomization to crisis resolution. RESULTS: Mean (SD) duration of the painful episodes was 141 (42) hours in the placebo group compared with 133 (41) hours in those treated with purified poloxamer 188, a 9-hour reduction (P =.04). Subset analyses indicated an even more pronounced purified poloxamer 188 effect in children aged 15 years or younger (21 hours; P =.01) and in patients who were receiving hydroxyurea (16 hours; P =.02). Finally, the proportion of patients achieving crisis resolution was increased by purified poloxamer 188 (65/126 [52%] vs 45/123 [37%]; P =.02). Similar results were observed in children aged 15 years or younger (22/37 [60%] vs 10/36 [28%]; P =.009) and in patients who were also receiving hydroxyurea (12/26 [46%] vs 4/28 [14%]; P =.02). CONCLUSIONS: A decrease in the duration of painful episodes and an increase in the proportion of patients who achieved resolution of the symptoms were observed when the purified poloxamer 188-treated patients were compared with the patients receiving placebo. However, the difference between these groups was significant but relatively small. In subgroup analysis, a more significant effect on both parameters was observed in children and in patients who were receiving concomitant hydroxyurea. It is important to confirm both of these observations in further prospective trials.

Adolescent↗
PubMed1998

Significance of sporadic deceleration during antepartum testing in term pregnancies.

We have investigated the significance of single sporadic deceleration during reactive nonstress testing in normal pregnancies at term. A prospective study was performed during a 1-year period including 4742 nonstress tests performed between the 38th and 42nd weeks of pregnancy in patients referred to our department for antepartum testing and without any complication or pathology. Nonstress test (NST) was carried out with the patient lying on her left side, and was defined as reactive if at least two accelerations of 15 beats/min (bpm) or more lasting 15 sec were observed in a 20-min period. Sporadic deceleration was defined as a decrease in the fetal heart rate to less than 90 bpm or a decrease of 40 bpm below the baseline, lasting at least 2 min. The sporadic deceleration was considered as single when only one appeared in the first 20 min of monitoring and repeated when observed again once in at least one subsequent monitoring. Thirty-four cases of single sporadic deceleration were observed among women with reactive NST. In 14 cases there were repeated sporadic decelerations. The patients were divided into two groups according to the presence or absence of repeated decelerations. Outcomes of patients with repeated sporadic decelerations were compared with a group of 34 patients where sporadic decelerations were not observed during the antepartum testing. A significantly higher percentage of pathological fetal heart rate traces during labor were observed in the group of repeated decelerations. In conclusion the presence of repeated sporadic decelerations during a reactive NST suggests that the cause of cord compromise is persistent and recurrent cord compression is possible. Therefore, in these cases an increased fetal risk could be expected.

Adult↗
PubMed1997

The ratio between carcinoma antigen-125 levels in the seminal plasma and serum may be a marker for fertilization in intracytoplasmic sperm injection.

OBJECTIVE: To assess the relationship between tumor marker carcinoma antigen-125 levels in seminal plasma and serum and fertilization rates in an IVF program, using intracytoplasmic sperm injection (ICSI). DESIGN: A prospective study. SETTING: IVF Unit, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. PATIENT(S): Twenty-five infertile patients with severe oligo-terato-asthenospermia syndrome and 25 fertile male donors. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Serum and seminal plasma carcinoma antigen-125 concentrations and fertilization rate per cycle. RESULT(S): In the infertile group, the seminal plasma carcinoma antigen-125 levels ranged from 22.0 to 1,284.0 U/mL (mean level +/- SD, 229.9 +/- 274.2 U/mL). In the normospermic fertile male donors, the seminal plasma carcinoma antigen-125 concentrations ranged from 12.2 to 336.7 U/mL (mean level +/- SD, 110.1 +/- 91.6 U/mL). This difference was statistically significant. The mean +/- SD ratio between the seminal plasma/serum carcinoma antigen-125 levels differed significantly between the infertile group (47.9 +/- 61.3) and the fertile male donors (5.7 +/- 3.5). In the infertile group, the ratio between the seminal plasma/serum carcinoma antigen-125 levels was found to be negatively correlated with the oocyte fertilization rate. CONCLUSION(S): The ratio between carcinoma antigen-125 levels in the seminal plasma and serum may be an indirect marker for male infertility and fertilization rate in IVF treatment using ICSI.

Adult↗
PubMed1997

The behavior of follicle cysts formed after long-acting gonadotropin-releasing hormone analog administration in patients with polycystic ovarian syndrome.

This study was conducted to examine the effect of ovarian cysts that develop after administration of a gonadotropin-releasing hormone (GnRH) analog during an ovulation induction program for patients with polycystic ovarian syndrome. Twenty-eight women received Decapeptyl Continuous Release for 70 cycles starting on day 3 of the menstrual cycle, after exclusion of any ovarian pathology by transvaginal ultrasonography. Fifteen days later ultrasonography was again performed and serum estradiol estimated. Cystic structures > or = 20 mm in the ovaries were defined as follicle cysts. In three cycles follicle cysts developed and low estradiol levels were measured (Group 1). In another six cycles cysts developed after GnRH analog, and elevated estradiol levels were found (Group 2). In the latter, estradiol decreased 3 to 7 days later, with cyst regression in three cases. Ovulation induction with human menopausal gonadotropin (hMG) was initiated only if the estradiol level was < or = 20 pg/ml, otherwise induction was postponed until estradiol decreased, disregarding the presence of cysts. When 2 to 3 follicles were > or = 18 mm, and generally when estradiol levels were < 1500 pg/ml, human chorionic gonadotropin was administered. All the cycles were ovulatory and two women from Group 2 conceived. The development of follicle cysts with low serum estradiol levels after GnRH analog administration represents a benign condition and is not a contraindication for hMG stimulation. In cases with elevated estradiol levels, ovulation induction can be postponed until the estradiol has decreased. Our study revealed good ovulatory and pregnancy rates as a result.

Adult↗
PubMed1996

A follicular scoring system for monitoring ovulation induction in polycystic ovary syndrome patients based solely on ultrasonographic estimation of follicular development.

OBJECTIVE: To assess the predictive value of a follicular scoring system for monitoring ovulation induction in polycystic ovary syndrome (PCOS) patients, solely with ultrasound (US). DESIGN: Ultrasound measurements were performed on alternate days to define a serial follicular score for monitoring ovulation induction with hMG alone, as well as GnRH analogue and hMG, in comparison with E2 concentration obtained on the same day. SETTING: Outpatient Infertility Clinic, Department of Obstetrics and Gynecology. PATIENTS: Thirty-four consecutive PCOS patients treated for 63 cycles. MAIN OUTCOME MEASURE: The follicular score was established considering the summation of points obtained after measuring the mean diameter of each follicle > 5 mm, as follows: 5 to 8 mm = 1 point, 9 to 12 mm = 1.5 points, 13 to 16 mm = 2 points, > or = 17 mm = 3 points. RESULTS: Follicular score correlated positively with E2 concentrations. A score of > or = 30 points was associated with E2 levels of concentration that reached > 1,500 pg/mL (conversion factor to SI unit, 3.671) and could predict ovarian hyperstimulation. A lower follicular score allowed hCG administration. CONCLUSIONS: A follicular scoring system may be a safe, simple, and highly efficient method to replace serial E2 measurements in monitoring ovulation induction. Moreover, ovarian hyperstimulation may be predicted.

Adult↗
PubMed1995

[Peak follicular estradiol (E2) levels and midluteal progesterone/E2 ratios in ongoing pregnancies and nonconception cycles after ovulation induced with gonadotropins].

We assessed the predictive value of peak follicular estradiol (E2) levels and progesterone/E2 ratios at the time of implantation (midluteal phase) in cycles resulting in pregnancies and in nonconception cycles after ovulation induced by hMG. hMG, administered to 31 consecutive patients with ovulatory dysfunction, resulted in 13 conception and 27 nonconception cycles. It was started on day 5 of the cycle and continued until at least 1 follicle was > 18 mm and E2 levels exceeded 300 pg/ml, when HCG, 100,000 IU, was administered. Baseline hormonal profile, peak follicular E2, serum E2, progesterone levels 7 days after hCG administration, and progesterone/E2 ratios were compared between ongoing pregnancies and during nonconception cycles. There was a significant difference in peak follicular E2 levels between ongoing pregnancies and nonconception cycles (means +/- SD: 1453 +/- 580 to 1176 +/- 275, pg/ml, p < 0.05). The length of follicular phase and the number of hMG ampules administered were similar in both groups. There was no difference in midluteal progesterone/E2 ratios (131 +/- 16.9 vs 124 +/- 27.5). E2 levels the day of hCG administration were higher in cycles leading to pregnancies. We conclude that mean midluteal progesterone/E2 ratios cannot be used to predict the outcome of cycles after ovulation induction with hMG.

Adult↗
PubMed1994

Outcome of pregnancies associated with marked gestational thrombocytopenia.

The purpose of this prospective study was to investigate the outcome of pregnancies associated with marked gestational thrombocytopenias (< 100,000/mm3) including postpartum resolution and neonatal influence. Over a period of 18 months, 20 cases of thrombocytopenia were observed; of them 19 were diagnosed as gestational thrombocytopenia with platelet values of < 100,000/mm3. Fifteen women returned to a normal platelet count within two weeks after delivery and four within four weeks. No cases of thrombocytopenia were found among the infants and no cases of coagulation disturbance were observed in the mothers at delivery or in the postpartum period. The findings of the present study indicate that in cases of gestational thrombocytopenia, apart from a careful maternal and fetal surveillance, no intervention is necessary during pregnancy or delivery if there is no obstetrical indication.

Adult↗
PubMed1994

Comparative study of extra-amniotic prostaglandin F2 alpha infusion and increasing intravenous oxytocin for termination of second trimester missed abortion.

Extra-amniotic infusion of prostaglandin F2 alpha (PGF2 alpha) and intravenous (IV) oxytocin in increasing doses were compared in a retrospective study to establish the efficacy of the two methods for termination of pregnancies with second trimester missed abortion. Sixty women with this complication underwent pregnancy termination, 28 by extra-amniotic infusion of PGF2 alpha and oxytocin augmentation, if necessary, and 32 by IV oxytocin in increasing doses. All patients in the PGF2 alpha group aborted within 24 hours from onset of infusion and seven of them needed oxytocin augmentation. There were nine failures in the oxytocin group and the other 23 aborted within 17 hours. The mean (plus or minus standard error of the mean) induction-abortion interval was significantly less in the oxytocin group (6.9 +/- 3.4 hours) than in the PGF2 alpha group (12.6 +/- 5.7 hours) p < 0.001. Eight patients in the group had mild side effects, such as nausea, flushes or transient hypotension. Uterine hypertonus was observed in two women receiving PGF2 alpha and treated by temporary interruption of the infusion. In the oxytocin group, one patient had coagulation disturbances and one, hemorrhage. We conclude that extra-amniotic PGF2 alpha infusion is more effective than IV oxytocin in increasing doses, for termination of second trimester missed abortion, but takes effect more slowly. We can assume that further use of IV oxytocin immediately after termination of the PGF2 alpha administration can shorten the induction-abortion interval.

Abortion, Missed↗
PubMed1992

Intrauterine PGF2 alpha infusion for termination of pregnancies with second-trimester rupture of membranes.

Intrauterine prostaglandin (PG) F2 alpha infusion and intravenous (IV) oxytocin infusion were compared to evaluate the effectiveness of the two methods for termination of pregnancies with second-trimester rupture of membranes. Twenty-two women with this complication were randomly allocated to receive either 20 mg PGF2 alpha, diluted in 500 mL of NaCl 0.9% and administered through a Foley catheter inserted through the cervix, or IV oxytocin infusion in increasing doses. All subjects in the PGF2 alpha group aborted after the first administration. Repeat infusion was necessary in three oxytocin-treated subjects. The mean (+/- SD) induction-abortion interval was significantly shorter in those receiving PGF2 alpha (6.7 +/- 1.2 hours) than in those receiving oxytocin (8.8 +/- 2.7 hours). Minor side effects, such as nausea and vomiting, were observed in three women during PGF2 alpha infusion and were treated symptomatically and by temporary interruption of the infusion. Uterine hypertonus, observed in one subject in each group, was treated by temporary cessation of the infusion. We conclude that intrauterine PGF2 alpha infusion seems more effective than IV oxytocin for termination of pregnancies with second-trimester rupture of membranes.

Abortion, Therapeutic↗
PubMed1988

Facilitation of Hb S polymerization by the substitution of Glu for Gln at beta 121.

In an effort to clarify the role of Glu-beta 121 of Hb S molecules in polymerization, we studied the solubility and kinetics of polymerization of various mixtures of deoxyhemoglobins S (Glu-beta 6----Val) and D Los Angeles (Glu-beta 121----Gln). It is known that patients with Hb S-D Los Angeles have a relatively severe clinical course. Mixtures of Hb S and Hb D Los Angeles polymerized after a distinct delay time, the length of which depended on the initial hemoglobin concentration and the fraction of Hb S in the mixture. There was a linear relationship between the logarithmic plot of delay time and initial hemoglobin concentration. The line for a 1:1 mixture of Hb S and Hb D Los Angeles shifted to the right of that for deoxy-Hb S by 0.08. This shift is much smaller than the shift of 0.32 for 1:1 AS mixtures. From these data, the probability factor for nucleation of S-D Los Angeles hybrid hemoglobin was calculated to be 1.16, which is higher than that of Hb S (1.0) and AS hybrid hemoglobin (0.5). The degree of co-polymerization of Hb D Los Angeles in S-D Los Angeles mixtures was similar to that of Hb A in AS mixtures. The critical concentration for the polymerization of Hb D Los Angeles was between that of Hb A and Hb Machida, which has the same amino acid substitution (Glu----Gln) at the beta 6 position. These results suggest that the protein interaction of Hb S molecules during nucleation involves at least two steps. First, the Val-beta 6 of a Hb S molecule interacts hydrophobically with the Phe-beta 85 and the Leu-beta 88 of an adjacent Hb S molecule. In the second step, Glu-beta 121 weakens the interaction with His-beta 116 and Pro-alpha 114. The substitution of Glu-beta 121----Gln may strengthen this second reaction and facilitate nucleation as well as polymerization.

Glutamates↗
PubMed1988

Breast electrostimulation for the induction of labor.

The use of breast stimulation to promote cervical ripening and initiate labor has been studied frequently. However, the various mechanical methods that have been suggested cannot be adequately controlled by the physician. We studied breast electrostimulation as a controllable method of initiating labor in 21 women. This technique successfully induced labor in 15 women, including all nine with premature rupture of membranes. The six (of 12) women without premature rupture of membranes who failed to go into labor each had a Bishop score of 4 or less. All of the successfully induced women delivered vaginally. The time interval from the start of stimulation to birth ranged from 2-13.5 hours, and all infants were born in good condition. Uterine hyperactivity occurred in five cases, but was controlled easily by adjusting the electrical variables of the stimulation. Further work will be needed to establish clearly the indications and safety of breast electrostimulation for induction of labor.

Breast↗
PubMed1985

The structural organization of skeletal proteins influences lipid translocation across erythrocyte membrane.

In order to define the influence of skeletal protein organization on transmembrane phospholipid movement in erythrocyte membranes, we measured the translocation rate of lysophosphatidylcholine in pathologic red cells. A simple method based on the differential extraction of lysophosphatidylcholine from the red cell membrane by saline and albumin solutions was used to quantitate the translocation rate. Two groups of pathologic red cells were chosen for these studies: red cells with quantitative deficiencies of the skeletal proteins, spectrin and protein 4.1, and sickle erythrocytes in which controlled reorganization of the membrane was induced by hemoglobin polymerization. Marked increase in lipid translocation rate was seen in red cells having quantitative deficiencies of spectrin and protein 4.1. The magnitude of the increase in translocation rate in spectrin-deficient red cells was related to the magnitude of protein deficiency. Translocation rate in sickle erythrocyte membranes increased by 50% upon deoxygenation as a result of sickle hemoglobin polymerization. No increase in translocation rate was seen in normal cells upon deoxygenation. By manipulating the extent of membrane reorganization that occurred following deoxygenation of sickle cells, we have been able to show that skeletal reorganization induced by hemoglobin polymerization and not hemoglobin polymerization per se is responsible for the increase in translocation rate. Together, these findings imply that the structural organization of membrane skeletal proteins plays an important role in regulating the rate of transbilayer movement of lipids across the erythrocyte membrane.

Anemia, Sickle Cell↗