Biomedical subjects

E Sivan

Publications and source records attributed to E Sivan.

At least 19 recordsLinked to original sources

PubMed2001

One or two hours postprandial glucose measurements: are they the same?

OBJECTIVE: This study was undertaken to compare the rate of abnormal glucose levels measured after 1 hour (>140 mg%) with those measured after 2 hours (>120 mg%) postprandially in women with gestational diabetes mellitus (GDM). STUDY DESIGN: Sixty-eight women were included in this study. All had GDM based on the criteria of Carpenter-Coustan. Women with fasting glucose levels of 105 mg% or more were excluded from the study. All women were initially treated by diet. All women measured daily capillary blood glucose levels when fasting as well as 1 hour and 2 hours postprandially for 1 week, immediately after diagnosis of GDM. Glucose levels were obtained by memory-based glucometers. All women were followed in a specialized gestational-diabetes clinic throughout the pregnancy. Insulin therapy was started on an individual basis according to common clinical criteria. Epidemiologic and perinatal data were collected from medical charts. RESULTS: The average age of the women was 30.8 +/- 5.4 years. Thirty-five percent of participants were primipara. The mean gestational age at diagnosis was 28.8 +/- 5.4 weeks. Glucose measurements included 618 readings during fasting and 2730 either 1 hour or 2 hours postprandial. Rates of abnormal glucose (>95 mg% when fasting; >140 mg% 1 hour or >120 mg% 2 hours after each meal) per person were the following: fasting, 27.1% abnormal glucose measurements; postbreakfast, 22.4% abnormal levels after 1 and 8.5% after 2 hours (P < .01); postlunch, 16.4% abnormal levels after 1 hour and 18.2% after 2 hours (not significant); postdinner, 16.3% abnormal levels after 1 hour and 30.1% after 2 hours (P < .01). CONCLUSION: The rate of abnormal values was 2.5-fold greater 1 hour postbreakfast than 2 hours postbreakfast, in contrast to an opposite ratio of a 2-fold increase in the rate of abnormal values 2 hours postdinner versus 1 hour postdinner. Therefore, differential measurement (1 hour after breakfast and 2 hours after dinner) might impose stricter criteria for controlling blood glucose levels. Further clinical research should explore whether differential measurements might reduce the rate of diabetes-associated complications.

Adult↗

PubMed2001

Insulin secretion during and after pregnancy in patients with gestational diabetes mellitus.

We have determined prehepatic insulin secretion rates (ISRs) in seven patients with gestational diabetes mellitus (GDM) and in eight age- and weight-matched nondiabetic pregnant women during late gestation (third trimester) and again postpartum. Plasma glucose concentrations were raised to approximately 8.9 mM with iv glucose (hyperglycemic clamping), and ISRs were determined by deconvolution of peripheral C-peptide concentrations using C-peptide kinetic parameters that were obtained in every patient during late gestation and again postpartum. Plasma insulin levels were measured by RIA with an antibody with minimal (<0.2%) cross-reactivity with proinsulin. During late gestation, women with GDM were more insulin resistant than nondiabetic controls and had significantly lower ISRs (689 vs. 849 pmol/min, P < 0.05) and glucose uptake rates (30.6 vs. 49.4 micromol/kg.min, P < 0.05) in response to hyperglycemia. Postpartum, ISRs and insulin resistance decreased in women with GDM and controls (ISR by 43% and 43%, respectively, and insulin resistance by 75% and 118%, respectively), and both groups had similar ISRs (352 vs. 408 pmol/min, nonsignificant). Women with GDM, however, continued to be more insulin resistant than controls. In summary, patients with GDM during late pregnancy not only had severe deficiencies in ISR but, in addition, were more insulin resistant than controls. Postpartum, insulin resistance and ISRs (and plasma insulin levels) improved in both groups, and ISRs (and plasma insulin levels) were no longer significantly different in patients with GDM and controls. Insulin resistance, however, remained higher in women with GDM, and their glucose uptake remained lower. We concluded that the women with GDM had a major ss-cell defect that made it impossible for them to compensate for their increased level of insulin resistance, which occurred during late pregnancy.

3-Hydroxybutyric Acid↗

PubMed2000

Segmentary fetal branch pulmonary artery blood flow velocimetry: in utero Doppler study.

OBJECTIVE: To evaluate changes in human, fetal segmentary, pulmonary artery blood flow velocimetry throughout pregnancy. DESIGN: Ninety-nine women with a singleton, low-risk gestation between 14 and 37 weeks of pregnancy were selected to participate in a prospective, cross-sectional study. All fetuses were evaluated using power and color Doppler ultrasound. Flow velocity waveforms at three sites of the right pulmonary artery were obtained. The pulsatility index (PI) was calculated in the proximal, mid and distal segment of the pulmonary artery. Mean values and 95% confidence interval (CI) for each segment were determined in correlation with gestational age. RESULTS: A full study that included Doppler measurements of all three segments of the pulmonary artery was completed on 99 fetuses. The highest mean PI of 2.36 was obtained in the proximal segment of the right pulmonary artery (CI = 2.29-2.42), whereas in the mid and distal segments the mean PI decreased significantly to 1.57 (CI = 1.53-1.61) and 1.02 (CI = 1.0-1.0) (P < 0.001), respectively. Throughout gestation, the mean PI measurements in the proximal, middle and distal segments of the branch pulmonary artery increased slightly, but without statistical significance (r = 0.274, 0.248, 0.047), respectively; (P > 0.5). CONCLUSIONS: The data obtained suggests that pulmonary circulation maintains stable vascular resistance during gestation in the human fetus. However, the PI obtained from the separate segments of the branch pulmonary artery is unique and each differs from the other, reflecting the proximity to the heart and the peripheral impedance at each location.

Adult↗

PubMed1999

Fuel metabolism during pregnancy.

This article reviews carbohydrate and fat metabolism in both healthy pregnant women and women with gestational diabetes. Emphasis is placed on more recent investigations that have utilized stable, nonradioactive isotopes with insulin clamps to study gestational fuel metabolism. In early pregnancy, glucose-stimulated insulin secretion is increased, insulin sensitivity is unchanged or enhanced, and glucose tolerance is normal or slightly improved. Late gestation is characterized by accelerated fetal growth, rising concentrations of several diabetogenic hormones, and increased insulin resistance. The increased resistance reduces maternal glucose utilization, sparing carbohydrates for the rapidly growing fetus. The inhibitory effect of insulin on the rate of lipolysis is also significantly reduced during the third trimester of pregnancy. An earlier than normal switch from carbohydrate to fat utilization serves to promote the use of lipids as a maternal energy source. Women with gestational diabetes have been reported to have either comparable or increased insulin resistance during late gestation with several studies also demonstrating reduced insulin secretory capacity.

Carbohydrate Metabolism↗

PubMed1999

Effect of insulin on fat metabolism during and after normal pregnancy.

Whereas development of resistance to the action of insulin on glucose metabolism during gestation has been recognized, it is presently not known whether there is also resistance to the action of insulin on lipid metabolism. We have, therefore, examined the effect of physiological hyperinsulinemia (during euglycemic-hyperinsulinemic clamping) on free fatty acid (FFA) turnover in seven nondiabetic overweight or obese women during and after pregnancy. Basal rates of FFA release, oxidation, and reesterification and basal plasma FFA concentrations were not significantly different from each other during the 2nd and 3rd trimester of pregnancy and postpartum. During euglycemic-hyperinsulinemic (approximately 500 pmol/l) clamping, however, lipolysis was significantly less inhibited during the 3rd trimester (from 7.0 +/- 0.9 to 4.9 +/- 0.9 micromol x kg(-1) x min(-1), -30%) than during the 2nd trimester (from 8.4 +/- 0.6 to 4.1 +/- 0.9 micromol x kg(-1) x min(-1), -51%) and postpartum (from 8.5 +/- 1.1 to 4.2 +/- 0.6 micromol x kg(-1) x min(-1), -51%). Similarly, fat oxidation was not inhibited at all (from 3.5 +/- 0.3 to 3.8 +/- 0.5 micromol x kg(-1) x min(-1)) during the 3rd trimester but was suppressed by 51% (from 3.9 +/- 0.2 to 1.9 +/- 0.3 micromol x kg(-1) x min(-1)) during the 2nd trimester and by 38% (from 2.6 +/- 0.7 to 1.6 +/- 0.5 micromol x kg(-1) x min(-1) postpartum. These data demonstrated that resistance to the action of insulin on lipolysis and on fat oxidation developed during late gestation and disappeared postpartum.

Adult↗

PubMed1998

Leptin in human pregnancy: the relationship with gestational hormones.

OBJECTIVES: The aims of the study were (1) to examine the relationship between leptin and placental hormones by measuring serial changes in serum levels of leptin during and after pregnancy and (2) to study the effects of several gestational hormones on leptin release from fully differentiated 3T3-L1 adipocyte cell cultures. STUDY DESIGN: Serum levels of leptin were measured throughout pregnancy and at 3 months post partum in 29 healthy women and were also measured in 18 healthy women at delivery by cesarean section and on postpartum day 3. In addition, 3T3-L1 mouse adipocytes were incubated for 24 hours in media containing various reproductive hormones and leptin production was measured. RESULTS: Serum leptin levels increased significantly (8.4 +/- 0.9 vs 13.5 +/- 1.5 ng/mL; P <.001) between the first 2 trimesters of pregnancy but not between the second and third trimesters. These changes in leptin did not correlate significantly with changes in body mass index. Leptin levels dropped significantly during the immediate postpartum period, from 34.1 +/- 4.9 at cesarean delivery to 7.3 +/- 1.4 ng/mL on postpartum day 3 (P <.001). Fasting insulin level did not correlate significantly with leptin level during pregnancy but did so during the postpartum period (r = 0.60; P <.05). Leptin secretion from 3T3-L1 adipocytes was increased significantly when cells were cultured with human chorionic gonadotropin (150%, P <.01) and also when they were cultured with estrogen (120%, P <.03). CONCLUSION: The data suggest that leptin production by adipose tissue is stimulated by several hormones of pregnancy, which may contribute to the increased leptin levels observed during gestation.

3T3 Cells↗

PubMed1998

Macrosomia does not predict overweight in late adolescence in infants of diabetic mothers.

OBJECTIVE: To determine the predictive value of macrosomia for overweight later in adult life in infants of diabetic mothers. DESIGN: Data from the computerized records of the Jerusalem Perinatal Study were matched to measurements made at age 17 obtained from the military draft medical examination records. PARTICIPANTS: 10,891 infants born in Jerusalem between November 1974 and February 1976. MAIN OUTCOME MEASURES: Macrosomia based on 90th percentile birth weight for gestational age and overweight defined as the 90th percentile for body mass index at age 17. RESULTS: Diabetes was diagnosed in 87 (0.8%) of the mothers. Thirty-one (35.6%) of the infants of the diabetic mothers were macrosomic compared to 1012 (9.4%) of the siblings of nondiabetic mothers (p < 0.001). At 17 years of age 10.3% vs. 9.4% of the siblings of diabetic vs. nondiabetic mothers were overweight (p > 0.05). The rate of adolescent overweight in macrosomic vs. nonmacrosomic subjects was 12.3% vs. 9.7% (p < 0.01) in siblings of nondiabetic mothers, and 16.1% vs. 7.1% (p > 0.05) for diabetic mothers. The sensitivity and specificity, in diabetic mothers, of macrosomia for overweight at age 17 was 44.4% and 66.7%, respectively. The positive and negative predictive value of macrosomia for overweight at age 17 was 16.1% and 92.9%, respectively. CONCLUSIONS: The risk of adolescent overweight was significantly increased among macrosomic infants, although this trend did not reach statistical significance in the smaller group of infants born to diabetic mothers. Macrosomia among infants of diabetic mothers had little predictive value for overweight in late adolescence.

Adolescent↗

PubMed1998

Pregnancy outcomes among women with and without diabetic microvascular disease (White's classes B to FR) versus non-diabetic controls.

The objective of this paper is to evaluate the impact of contemporary management on the maternal and neonatal outcomes of pregnancies complicated by diabetes in women with microvascular disease versus women without microvascular disease. The study population consisted of two hundred and eighty-eight (288) pregnant women with pregestational diabetes and one hundred and fifty (150) healthy pregnant controls. Diabetic women were grouped according to the presence (n = 103) or absence of diabetic microvascular disease (n = 185). Data were collected regarding diabetes management, level of glycemic control, and the development of antenatal complications. Maternal and neonatal outcomes were compared among the three groups. Women in the diabetes groups were stratified according to mean blood glucose levels and glycosylated hemoglobin during each trimester. There was no significant difference found between the two diabetes groups in terms of preterm labor, polyhydramnios, pyelonephritis, and growth restriction. The only maternal complications that occurred with increased incidence among women with microvascular disease were acute hypertensive complications (51.6 vs. 32.9%; p<0.05). However, when the diabetes groups were compared to healthy controls, a significant difference was seen in all maternal and neonatal complications. Preterm delivery, polyhydramnios, and large-for-gestational-age (LGA) infants were associated with poor third-trimester metabolic control as compared with others in satisfactory metabolic controls: 30.8 vs. 11.4% for preterm delivery; 17.3 vs. 5.1% for polyhydramnios; 51.9 vs. 33.9% for LGA; p<0.05. Congenital malformations were associated with poor first-trimester glucose control (5.8 vs. 1.3% anomalies in well-controlled women). Furthermore, major congenital malformations were also significantly increased in the offspring of women with diabetic microvascular disease 6.8%, as compared to 1.69% in diabetic women without microvascular disease; p<0.01. The incidence of hypertensive complications did not differ between the two diabetic groups. Pregestational diabetic women with and without microvascular disease can be counseled to anticipate comparably favorable pregnancy outcomes, although maternal and neonatal complications may exceed that experienced by pregnant women without diabetes mellitus.

Adult↗

PubMed1998

Free fatty acids and insulin resistance during pregnancy.

The purpose of this study was to determine whether elevation of plasma free fatty acids (FFA) in early pregnancy would cause alterations in insulin-stimulated glucose disposal similar to those occurring in late gestation. Seven glucose-tolerant women underwent 4-h euglycemic hyperinsulinemic (1 mU/kg.min) clamping during the early second trimester of pregnancy (14-17 weeks) on 2 consecutive days, receiving either lipid (Liposyn II; 1.5 mL/min) and heparin (0.4 U/kg.min; L/H) or saline/glycerol (2.25 g/h; S/G) infusions. Rates of total body glucose disposal (6,6-2H2 glucose) and of carbohydrate and fat oxidation (indirect calorimetry) were determined at hourly intervals. Blood glucose was clamped at about 85 mg/dL. Plasma FFA increased from 290 +/- 50 to 1000 +/- 139 mumol/L during L/H infusion and decreased from 351 +/- 60 to 35 +/- 11 mumol/L during S/G infusion. L/H infusion inhibited insulin stimulation of total body glucose disposal by 28% compared with S/G infusion (from 6.7 +/- 0.7 to 4.9 +/- 0.6 mg/kg.min; P < 0.01). L/H infusion increased fat oxidation from 0.73 +/- 0.04 to 1.26 +/- 0.2 mg/kg.min (P < 0.05) and decreased carbohydrate oxidation from 2.0 +/- 0.2 to 1.6 +/- 0.2 mg/kg.min (P < 0.05). Endogenous glucose production decreased equally by approximately 70% during L/H and S/G infusions. These data showed that elevating plasma FFA levels during early pregnancy inhibits total body glucose uptake and oxidation. We conclude that elevation of plasma FFA can contribute to the peripheral insulin resistance commonly observed during late pregnancy.

Adult↗

PubMed1998

Is self-monitoring of blood glucose necessary in the management of gestational diabetes mellitus?

There continues to be controversy regarding the role of blood glucose in the management of pregnant women with gestational diabetes mellitus (GDM), specifically with regard to the use of capillary versus venous samples, as well as the frequency and timing of blood glucose determinations. At the Third International Workshop Conference it was noted that "self-monitoring of capillary blood glucose has been useful in allowing the woman to participate in her own management," but its utility "in the mild GDM not requiring insulin, although reasonable and logical, has not been formally proved." This article reviews the existing evidence in the literature regarding the impact of self-monitoring of blood glucose on outcomes in pregnancies complicated by gestational diabetes. Data regarding the optimal timing, accuracy, costs, and psychosocial effects of self-monitored glucose determinations will also be explored.

Blood Glucose Self-Monitoring↗

PubMed1998

HCFA documentation guidelines and the need for discrete data: a golden opportunity for applied health informatics.

BACKGROUND: The medical community is shocked by the complexity of the documentation now required to support the Medicare billing codes. This situation represents an opportunity for Electronic Medical Records that use discrete data to become a central factor at the point of care by fulfilling these stringent documentation specifications. METHODS: This empirical study explores whether a discrete data EMR has the ability to generate automatically a report describing what billing code is consistent with the documentation recorded. We tested this hypothesis on HBOC Pathways SMR by attempting to create algorithms that reflected the HCFA guidelines. We validated this process using historical records from the Cleveland Clinic. RESULTS: All the data elements required by HCFA were available as discrete data. Using algorithms, the billing code consistent with the documentation of the health care encounter could be automatically generated. CONCLUSIONS: EMRs using discrete data can substantially reduce the burden placed on health care providers by HCFA's new documentation guidelines. This benefit creates a window of opportunity for health informatics to become an integral tool in the provision of health care. Using EMRs for billing purposes can help achieve the loftier goal of using EMRs for quality improvement.

Centers for Medicare and Medicaid Services, U.S.↗

PubMed1997

Free radical scavenging enzymes in fetal dysmorphogenesis among offspring of diabetic rats.

Recent studies have suggested that the fetal dysmorphogenesis in diabetic pregnancies is associated with an increase in embryonic oxygen-free radicals. This excess of oxygen-free radicals may result from either overproduction or decreased clearance by the enzymatic scavenging mechanism. However, there are no in vivo data on the activity of embryonic oxygen-free radical scavenging enzymes. The purpose of the current study is to investigate whether this increase in embryonic oxygen-free radicals is the result of a change in the activity of the fetal oxygen-free radical scavenging/antioxidant enzymes during pregnancy complicated by maternal diabetes in an in vivo rat model. Thirty-six Sprague-Dawley rats were randomly assigned to one of two study groups: nondiabetic control and an untreated diabetic group. On day 12, fetuses were examined for crown-rump lengths, somite numbers, and external anomalies. The activity of fetal oxygen-free radical scavenging enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), were determined. The untreated diabetic group of rats had a significantly higher mean blood glucose level than that of the nondiabetic controls and also a significantly lower weight gain, higher resorption rate, smaller embryonic size with lower total protein content, and a approximately 6-fold increase in the rate of fetal neural tube defects compared to the nondiabetic controls. Superoxide dismutase activity was significantly reduced in the embryos with neural tube defects regardless of maternal diabetic status (2.25 +/- 0.83 vs. 1.17 +/- 0.04 u/mg protein; P < 0.05). Glutathione peroxidase and catalase activity were significantly reduced in malformed versus normal-formed embryos of nondiabetic mothers (GPX-2.68 +/- 1.15 vs. 4.46 +/- 1.12 mu/mg protein, CAT -1.67 +/- 0.53 vs 2.49 +/- 0.61 u/mg protein respectively; P < 0.01). However, overall catalase activity was increased in embryos of diabetic mothers as compared to controls. Two-way analysis of variance identified fetal malformations as the variance associated with reduced fetal SOD activity, whereas maternal diabetes was associated with the increase in fetal catalase activity. Neither neural tube defect nor maternal diabetes was found to be the variable affecting fetal GPX activity, Fetal oxygen-free radical scavenging enzymes respond differently to the adverse environment created by maternal diabetes during pregnancy. Defects in embryonic SOD and catalase activity, regardless of maternal diabetic status, may reduce the ability of the fetus to clear free oxygen radicals, thereby exposing it to an increased oxidative load that may cause fetal dysmorphogenesis. The diabetic state of the mothers did not decrease embryonic activity of any of the scavenging enzymes. Therefore, although excess oxidative load, as observed in diabetes, may cause tissue injury and embryopathy, the mechanism does not appear to be a diabetes-induced reduction in the action of the scavenging enzymes.

Abnormalities, Drug-Induced↗

PubMed1997

Sonographic imaging of the fetal face and the establishment of normative dimensions for chin length and upper lip width.

Sonographic imaging of the fetal face is important because a number of chromosomal aberrations are associated with facial malformations. Prenatal diagnosis of abnormalities of the fetal chin and lips have been based on subjective assessment. The purpose of the current study was to establish normative dimensions for the objective assessment of the fetal face. A cross-sectional study was performed in 200 normal healthy singleton pregnancies between 16 and 38 weeks' gestation. Inclusion criteria included performance of a first or early second-trimester scan to confirm gestational age (GA). Exclusion criteria included birth weight < 10th or > 90th percentile for GA, and medical complications of pregnancy. Ultrasound measurements were made in the mid-sagittal plane and included chin length (CL) and upper lip width (ULW). A first-degree linear growth function was observed throughout pregnancy between GA and ULW (r = 0.87) and CL (r = 0.91). All measured data are expressed as mean +/- 2 SD. In conclusion, these results provide normative dimensions throughout gestation for the fetal upper lip and chin. These data are expected to serve as a basis for the objective assessment of the fetal face in high-risk conditions.

Anthropometry↗

PubMed1997

Leptin is present in human cord blood.

It has recently been reported that the ob gene receptor was expressed on human and murine hematopoietic stem cells and that the ob gene product leptin stimulated hemato- and lymphopoiesis at the stem cell level. These findings suggest a role for leptin in hemato- and lymphopoiesis during fetal development. There is at present no evidence, however, that leptin is synthesized and released by the fetus. To investigate this possibility, we have measured plasma leptin concentrations in the cord blood of 78 newborn infants. We found that leptin was present in all 78 infants in concentrations comparable with those found in adults (0.6-55.7 ng/ml). Overall, plasma leptin concentrations in the cord blood of infants correlated with birth weight (r = 0.74, P < 0.001). These observations show that leptin is synthesized and released by fetal fat cells. In addition, they are compatible with the concept that leptin may play a role in human fetal hematopoiesis.

Birth Weight↗

PubMed1997

Longitudinal study of carbohydrate metabolism in healthy obese pregnant women.

OBJECTIVE: To longitudinally characterize changes in insulin sensitivity in obese women during and after pregnancy. RESEARCH DESIGN AND METHODS: Six glucose-tolerant obese women underwent a 4-h euglycemic-hyperinsulinemic (500-600 pmol/l) clamping during the second (22.5 +/- 2 weeks [mean +/- SD]) and third trimester (36.8 +/- 0.9) of pregnancy and again 15.6 +/- 1.4 weeks after delivery. Rates of total body glucose turnover (with [6.6-2H2]glucose) and oxidation (with indirect calorimetry) were measured. RESULTS: There were no significant changes with respect to the action of insulin on rates of glucose disappearance (GRd), carbohydrate oxidation, or endogenous glucose production (EGP), comparing the second trimester of pregnancy with the nonpregnant (postpartum) state. The third trimester, however, was characterized 1) by reductions in insulin-stimulated GRd (-28%, P < 0.05, compared with the second trimester and -40%, P < 0.05, compared with postpartum); 2) by even larger reductions in insulin-stimulated carbohydrate oxidation (-46%, P < 0.05, compared with the second trimester and -54%, P < 0.02, compared with postpartum); and 3) by reduction of insulin suppression of EGP (-39% compared with -79% at the second trimester and -77% postpartum, P < 0.01). CONCLUSIONS: Glucose-tolerant obese women developed peripheral was well as hepatic insulin resistance during the third trimester of pregnancy. These alterations were reversed after delivery and appeared to be adaptive mechanisms to cope with the increased demand for glucose of the growing fetus.

Adaptation, Physiological↗

PubMed1997

Growth of the fetal forehead and normative dimensions developed by three-dimensional ultrasonographic technology.

Sonographic imaging of the fetal face is important since a number of chromosomal aberrations are associated with facial malformations. In the past, imaging of the fetal forehead and diagnosis of frontal bossing had been based on subjective evaluation using two-dimensional ultrasonography. The purpose of this study was to evaluate quantitatively the fetal forehead using three-dimensional technology to generate normative data throughout gestation. This should allow the objective diagnosis of abnormal growth of the fetal forehead, such as frontal bossing. We also report a case of a fetus with frontal bossing in whom the generated nomogram was applied. A cross-sectional study was performed in 130 normal healthy singleton pregnancies between 16 and 38 weeks' gestation. Using three-dimensional ultrasonography, a line connecting the apex of the philtrum and the nasion was drawn across the anterior forehead, which delineated the area of the forehead for analysis. The forehead length, forehead height, and forehead area under the curve were measured and the forehead index was calculated. A second order polynomial growth function was noted throughout gestation for the forehead length (r = 0.93), forehead height (r = 0.97), and forehead area (r = 0.97). The fetal forehead index remained relatively constant throughout gestation. The results of this study provide normative data of fetal forehead length, width, and area using three-dimensional ultrasonographic technology. Normative dimensions of the fetal forehead developed and presented herein are expected to serve as a basis for the objective assessment of presumed fetal facial abnormalities and may facilitate the detection of the associated syndromes. This is demonstrated in our case report of an achondroplastic fetus in whom all forehead dimensions were above the 95th percentile.

Craniofacial Abnormalities↗

PubMed1996

Primary peritoneal serous papillary carcinoma: a study of 25 cases and comparison with stage III-IV ovarian papillary serous carcinoma.

The clinical characteristics and treatment outcome of patients with primary peritoneal serous papillary carcinoma (PPSC) (n = 22) was compared with stage III-IV papillary serous ovarian carcinoma (PSOC) patients (n = 63). There were no statistically significant differences between the PPSC and PSOC patients with regard to the mean age, menopausal status, parity, ascites fluid volume, proportion of stage IV disease, and the rate of optimal debulking achieved. The median disease-free interval was 15 and 18 months; the median survival was 21 and 26 months; and the 5-year survival was 18 and 24% for the PPSC and PSOC groups, respectively. The median survival time for patients with a residual tumor > or = 2 cm was 20.5 and 24 months, and for residual tumor > or = 2 cm was 46 and 41 months, in PPSC and PSOC patients, respectively. Survival was thus better, in both groups, when residual disease at the end of the operation was < 2 cm, though this was statistically significant only for PSOC (P < 0.02). We conclude that patients with PPSC should be treated as other stage II-IV PSOC patients. Combining optimal debulking with a platinum-based chemotherapy may offer the patient the most effective treatment.

Aged↗

PubMed1996

Relationship between burst properties and sensitivity to input: a theoretical analysis.

This paper examines the sensitivity of endogenous bursters to a brief input pulse. The interneurons of the lobster cardiac ganglion were selected as a case study. Using a mathematical model specifically developed for the neurons in the cardiac ganglion of the lobster (Av-Ron et al., 1993), we show a tight link between burst characteristics and certain other parameters. We show that cells with different burst properties differ in their sensitivity to an input of a brief pulse. Irrespective of these differences, all cells display a bimodal response to a brief pulse applied during the quiescent period. During the first three-quarters of the quiescent period, they respond by producing a single spike at most. During the remaining one-quarter, the brief pulse can initiate the cells' intrinsic burst. Our predictions fit experimental results obtained by Tazaki and Cooke (1979). The results obtained herein are discussed with respect to fault tolerance considerations.

Animals↗