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Biomedical subjects

I Cetin

Publications and source records attributed to I Cetin.

54 records · Page 3Linked to original sources
PubMed1993

Impact of conceptus mass on glucose disposal rate in pregnant women.

The impact of an increasing fetal and placental mass on maternal glucose disposal rate (GDR) was studied in 17 pregnant women. Eleven pregnancies were singleton pregnancies, five were twin and one was a triplet pregnancy. Both the maternal fasting glucose concentration [Glc] and the total fetal and placental weight (W) were significantly correlated with an increased maternal GDR. Glucose concentration and conceptus weight were interdependent. The multiple linear regression of glucose disposal rate on glucose concentration and total weight is given by GDR = -1.573 + 0.176W + 0.932[Glc] +/- 0.24, r2 = 0.52, P < 0.01. These data are utilized to estimate the glucose utilization rate of the human conceptus at a fasting glucose concentration of 3.9 mM with a range of 10-15 mg.kg-1.min-1. Maternal GDR increases with increasing glucose concentration at a rate similar to that reported for newborn infants, consistent with a high glucose utilization by the uterus.

Adult↗
PubMed1992

Venous drainage of the human uterus: respiratory gas studies in normal and fetal growth-retarded pregnancies.

OBJECTIVE: To determine respiratory gas relationships between the uterine veins and umbilical vein in normal and pregnancies complicated by intrauterine growth retardation. STUDY DESIGN: Respiratory gases were measured in both uterine veins and the umbilical vein in eight normal and 13 pregnancies with intrauterine growth retardation. RESULTS: No significant differences were found in the placental versus nonplacental uterine veins. There was a significant correlation for umbilical and uterine venous values of PO2 (p less than 0.002) and PCO2 (p less than 0.004) in appropriate-for-gestational-age pregnancies, umbilical venous PO2 was always less than uterine venous PO2, and PCO2 always greater than uterine. The transplacental gradient was significantly higher in intrauterine growth retarded than appropriate-for-gestational-age pregnancies for both POC2 and PCO2. There was a lower uterine oxygen extraction in intrauterine growth retarded pregnancies (p less than 0.05). CONCLUSION: There is no consistent relationship between placental venous drainage in each uterine vein and placental location. The human placenta simulates a relatively inefficient venous equilibrator and the larger transplacental gradients in intrauterine growth retarded pregnancies may reflect differences in both perfusion pattern and placental structure.

Blood Gas Analysis↗
PubMed1992

Fetal serine fluxes across fetal liver, hindlimb, and placenta in late gestation.

Eleven studies of fetal serine fluxes were performed in chronically catheterized fetal lambs by continuous infusion of [1-13C]- and [U-14C]serine into a fetal brachial vein. At tracer serine steady state, samples were collected from the fetal abdominal aorta, umbilical vein, fetal hepatic vein, and fetal femoral vein and from the maternal femoral artery and uterine vein. Analyses were performed for plasma serine and glycine concentration, for serine and glycine 13C mole percent enrichment, and for whole blood 14CO2 and O2 concentrations. Uterine and umbilical blood flows were also measured. The placenta had a significant net uptake of fetal serine (2.1 +/- 0.5 mumol.min-1.kg-1, P < 0.01). Fetal plasma serine disposal rate (DR) was 42.5 +/- 3.9 mumol.min-1.kg-1.CO2 production from decarboxylation of fetal plasma serine represented 7.9 +/- 0.5% of DR, or 10.1 +/- 1.2 mumol CO2.min-1.kg-1. Fetal plasma glycine enrichment was 59.7 +/- 4.9% of fetal plasma serine enrichment. There was a significant loss of tracer serine from the fetal circulation into the placenta accounting for approximately 45% of infused tracer. Fifteen percent of this was converted to glycine and released into the umbilical circulation. There was a significant uptake of tracer serine by both fetal liver and fetal hindlimb with a significant CO2 production by both sites with serine oxidation predominantly in the carcass. These results indicate a high fetal serine disposal rate in the lamb, with rapid fetoplacental serine exchange, resulting in a net uptake of fetal serine by the placenta.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Glycine turnover and oxidation and hepatic serine synthesis from glycine in fetal lambs.

[1-13C]- and [1-14C]glycine were infused into chronically catheterized fetal lambs via a brachial vein. At tracer glycine steady state, samples were collected from the fetal abdominal aorta, umbilical vein, and fetal hepatic vein and from the maternal femoral artery and uterine vein. The samples were analyzed for plasma glycine and serine, for glycine and serine 13C atom% excess (APE), and for whole blood 14CO2 and O2 concentrations. Fetal plasma glycine disposal rate (DR) was 12.4 +/- 0.8 mumol.min-1.kg fetus-1.CO2 production from decarboxylation of fetal plasma glycine was 1.63 +/- 0.16 mumol.min-1.kg fetus-1 and represented 12.3 +/- 0.7% of DR. Approximately 50% of infused tracer glycine was taken up by the fetal liver with the release of labeled serine and CO2 in the fetal circulation. There was no detectable efflux of tracer glycine from the placenta into the maternal circulation. The tracer production of serine and CO2 accounted for 23 and 17%, respectively, of the hepatic tracer glycine uptake. The labeled CO2 released by the liver was a large fraction (approximately 70%) of the labeled CO2 produced by the fetus. The serine-to-glycine APE ratio in fetal plasma was approximately 5%. These results indicate that the fetal liver is the major site of fetal plasma glycine decarboxylation and of serine synthesis from plasma glycine.

Animals↗
PubMed1991

Plasma and erythrocyte amino acids in mother and fetus.

Plasma (P) and whole blood (WB) amino acid concentrations were measured in arterial and venous blood of 9 mothers and their fetuses at elective cesarean section and compared to values obtained in 5 normal nonpregnant women. Erythrocyte (E) amino acid concentrations were calculated from P and WB concentrations. E/P ratios were significantly greater than 1.0 in all groups studied. Alanine, glycine, and serine presented E/P ratios significantly higher in pregnant women than in control nonpregnant women. Fetuses presented significantly lower E/P ratios for lysine than pregnant and nonpregnant women. Uterine arteriovenous amino acid differences were not significantly different from zero in both plasma and erythrocytes. Umbilical venous-arterial differences were significantly positive for most essential amino acids in plasma, whereas they were not significantly different from zero in erythrocytes. This finding suggests that erythrocytes do not play a major role in the transfer of amino acids from the placenta to the fetus.

Amino Acids↗
PubMed1990

Umbilical amino acid concentrations in normal and growth-retarded fetuses sampled in utero by cordocentesis.

Fetal plasma amino acid concentrations were obtained by cordocentesis at midgestation in 11 normal (appropriate for gestational age) fetuses and at late gestation in 12 small-for-gestational-age fetuses, and at cesarean section in 14 normal term infants. In normal fetuses total molar amino acid concentrations and fetal/maternal total molar concentration ratios did not change significantly between the second and third trimesters. Fetal and maternal concentrations of most amino acids were significantly correlated at both midgestation and late gestation. Small-for-gestational-age fetuses had significantly lower concentrations of total alpha-aminonitrogen; this was mainly because of a reduction of the branched chain amino acids valine, leucine, and isoleucine, and of lysine and serine. Maternal arterial concentrations of phenylalanine, arginine, histidine, and alanine were elevated in small-for-gestational-age pregnancies. Thus there are only minor changes in amino acid concentrations between midgestation and late gestation in normal fetuses with a constant fetal/maternal ratio. In small-for-gestational-age infants a significant reduction in alpha-aminonitrogen and in most essential amino acids was demonstrable in utero weeks before delivery.

Amino Acids↗
PubMed1990

Lactate metabolism in normal and growth-retarded human fetuses.

Lactate concentration and oxygen content were measured in 21 normal (AGA) and 34 intrauterine growth-retarded (IUGR) infants at the time of elective cesarean section. Maternal lactate and umbilical arterial and venous lactate concentrations were significantly higher in IUGR infants compared with AGA infants. However, when IUGR patients were subdivided according to pulsatility index (PI) measurements of the umbilical artery, no differences were detected between AGA and IUGR patients with PI less than 4 SD, whereas IUGR patients with PI greater than 4 SD had higher lactate concentrations in maternal arterial blood and umbilical arterial and venous blood from both other groups. There was a significant inverse linear relationship between umbilical arterial lactate concentration and umbilical venoarterial differences for both lactate concentrations and for lactate/oxygen quotients. These relationships were significantly different in IUGR fetuses with PI greater than 4 SD compared with AGA and IUGR fetuses with PI less than 4 SD. AGA and IUGR fetuses with PI less than 4 SD have arterial lactate concentrations less than 2 mM even at low oxygen concentrations (O2 content less than 2 mM, O2 saturations less than 20%). At comparable levels of oxygenation, IUGR fetuses with PI greater than 4 SD have a marked lactacidemia. The data suggest that coupling Doppler assessment of flow velocimetry with biochemical analyses of fetal blood can be useful in identifying a subset of IUGR human fetuses at risk of intrauterine hypoxia.

Female↗
PubMed1988

Umbilical amino acid concentrations in appropriate and small for gestational age infants: a biochemical difference present in utero.

Plasma amino acid concentrations were determined in 28 pregnant women and their infants at term. Samples were obtained from 17 appropriate for gestational age and eight small for gestational age infants at cesarean section, while three small for gestational age fetuses were studied in utero by transabdominal cord sampling by means of ultrasonic guidance. Small for gestational age fetuses have significantly lower concentrations of alpha-aminonitrogen, compared with those of appropriate for gestational age fetuses, in both the umbilical artery and vein. Most of the difference is accounted for by the branched chain amino acids valine, leucine, and isoleucine. In contrast, hydroxyproline concentration is significantly higher in both the umbilical artery and vein of small for gestational age fetuses. The sum of the branched chain amino acid concentrations in the umbilical vein is directly related to maternal arterial values in both appropriate for gestational age and small for gestational age fetuses. Maternal arterial concentrations were slightly lower in small for gestational age fetuses and the regression analysis of umbilical venous versus maternal arterial branched chain amino acid concentrations was significantly different for small for gestational age and appropriate for gestational age infants. Umbilical venoarterial concentration differences in normal fetuses are significantly positive for most essential amino acids and for total alpha-aminonitrogen. In contrast, these differences were significant only for four essential amino acids in small for gestational age infants, while the total alpha-aminonitrogen venoarterial difference was not significant. The data obtained by transabdominal cord sampling from relatively undisturbed fetuses were in agreement with the data obtained at cesarean section; this information suggests that these differences between small for gestational age and appropriate for gestational age infants reflected steady-state conditions.

Amino Acids↗
PubMed1987

Cord sampling for the evaluation of oxygenation and acid-base balance in growth-retarded human fetuses.

In 14 pregnancies complicated by intrauterine growth retardation, the umbilical cord was sampled before delivery under ultrasonic guidance for rapid fetal karyotyping. Fetal blood was analyzed for respiratory gases, acid-base balance, and lactate concentrations. Two patients were excluded from the study because cord samples were diluted with amniotic fluid. In six patients (group 1), the clinical assessment warranted continuation of pregnancy. Cesarean sections were performed in the remaining eight patients (group 2) within 8 hours of cord sampling. The data from the two groups were compared with those obtained from umbilical venous blood at the time of elective repeat cesarean section in term appropriate for gestational age infants (controls). No significant difference in PO2 was found between groups 1 and 2 and controls. In contrast, there were significant differences in oxygen saturation and acid-base balance between groups 1 and 2. Lactate concentration was inversely correlated with pH and was elevated in five of six fetuses requiring a prompt cesarean section: In two of these five fetuses, nonstress fetal heart rate tracings were reactive. The results suggest that fetal blood biochemistry, and particularly lactate concentration, may represent an additional indicator of fetal well-being in pregnancies complicated by intrauterine growth retardation.

Acid-Base Equilibrium↗
PubMed1987

Respiratory gases, acid-base balance and lactate concentrations of the midterm human fetus.

Respiratory gases, acid-base balance, and lactate and hemoglobin concentrations were measured in 14 fetal blood samples between 17 and 21 weeks of gestation. The samples were obtained at the time of fetoscopy performed for prenatal diagnosis. Results have been compared with two reference groups: (a) 4 patients in whom fetal cord blood sampling was performed at 32-36 weeks of gestation, and (b) 10 patients at the time of elective cesarean section, 35-39 weeks. PO2 and oxygen saturations were significantly higher and hemoglobin concentration lower in the mid-gestation fetus. Acid-base balance was not significantly different. There was a significant correlation between maternal and fetal hemoglobin concentrations. The oxygen affinity of fetal blood was not significantly different from that described for term fetuses with a oxygen saturation of less than 90%.

Acid-Base Equilibrium↗
PubMed1986

The clinical relevance of the abdominal fetal electrocardiogram.

We investigated the duration of fetal electrocardiographic events during normal pregnancies and during pregnancies with fetal abnormalities. The fetal abdominal signal was processed and enhanced by means of the averaging technique after removing the maternal complex. In normal pregnancies P wave and QRS complex duration increases progressively from the 17th week up to the term: this increase parallels the gain in weight of the fetal heart and particularly of the ventricular mass. These results indicated that the duration of fetal complexes could be used as an index of the size, development and maturity of the fetal heart. When fetal growth retardation (FGR) is present, the weight of the fetal heart is significantly reduced, and is reflected in a decrease in QRS duration. In a series of 107 cases the sensitivity of this parameter in detecting FGR was 81% and the specificity 93%. Moreover no perinatal death nor Apgar values below 7 occurred in growth retarded fetuses with normal QRS duration, while in the group with shortened QRS neonatal deaths were 11% and Apgar scores below 7 26%. Abdominal FECG do provide important auxiliary information for prenatal diagnosis of congenital heart defects (CHD). Anomalies with abnormal atrioventricular connection were reflected in longer PR interval. Ventricular hypertrophia and hypoplasia were associated with increased or decreased QRS duration, respectively. Furthermore, the three fetuses which developed congestive heart failure showed prolonged QRS duration. In severe RH disease, chronic fetal anemia can lead to myocardial hypertrophy and cardiac enlargement.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiography↗
PubMedDate not supplied

Sickle cell thalassemia in pregnancy: a case report.

A 31-year-old pregnant woman at 20 weeks' gestation was sent to our hospital for fever, anemia, and arthralgias. As she was known to be a double heterozygote for beta-thalassemia and hemoglobin S, a diagnosis of hemolytic anemia caused by sickled red cells vasocclusive crises was made. The patient was submitted to partial exchange transfusion (PET) with a complete recovery. A second PET was performed at 36 weeks' gestation, and elective cesarean section was performed at 37 weeks, with the birth of a normal female neonate.

Adult↗
PubMedDate not supplied

Fetal amino acids in normal pregnancies and in pregnancies complicated by intrauterine growth retardation.

Plasma amino acid concentrations were measured in normal (AGA) and intrauterine growth retarded (IUGR) percutaneous umbilical blood sampling (PUBS) performed for prenatal diagnosis or at elective cesarean section. IUGR fetuses present significantly lower concentrations of most amino acids, with a significant reduction of the umbilical veno-arterial difference for total alpha-amino nitrogen. These findings are present early in growth retarded fetuses and may be potentially responsible for the growth retardation.

Amino Acids↗
PubMedDate not supplied

Fetal growth restriction: a workshop report.

Intrauterine growth restriction (IUGR) is associated with significantly increased perinatal morbidity and mortality as well as cardiovascular disease and glucose intolerance in adult life. A number of disorders from genetic to metabolic, vascular, coagulative, autoimmune, as well as infectious, can influence fetal growth by damaging the placenta, leading to IUGR as a result of many possible fetal, placental and maternal disorders. Strict definitions of IUGR and of its severity are needed in order to eventually distinguish among different phenotypes, such as gestational age at onset, degree of growth restriction and presence of hypoxia. This report explores and reviews some of the most recent developments in both clinical and basic research on intrauterine growth restriction, by seeking mechanisms that involve genetic factors, utero-placental nutrient availability and vascular growth factors. New exciting findings on the genomic imprinting defects potentially associated with IUGR, and the placental anomalies associated with the decreased nutrient transport are summarized. Moreover, recent data on angiogenic growth factors as well as new information arising from application of gene chip technologies are discussed.

Adult↗
PubMedDate not supplied

Giant cell pneumonia in a leukemic child in remission: a case report.

Giant cell pneumonia is a rare and uncommon type of lung infection developing as a complication of measles, especially in immunocompromised patients, whether their immune systems are affected primarily or whether they have acquired immune defects. As well as being uncommon, it is also atypical because of absence of the characteristic rash and of absent or low antibody titers against measles in most of the cases. It is known that cellular immunity is more important than humoral immunity in the host response to measles, so hypogammaglobulinemic patients with normal cellular immunity usually recover uneventfully from measles and also have the characteristic rash. We report a case with giant cell pneumonia that was confirmed by postmortem histopathological examination. We especially want to point out that even in the absence of rash, with the clinical and radiological features of pneumonia, measles should be considered in a patient, whether in remission or not, receiving immunosuppressive treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Femoral shaft fractures in children: technique of immediate treatment with supracondylar Kirschner wires and one-and-a-half spica cast.

Sixty-five children between 3.5 and 12 years of age with femoral shaft fractures were treated with fixed traction using supracondylar Kirschner wires incorporated in a one-and-a-half spica cast. Medial angulation up to 15 degrees, lateral angulation up to 5 degrees, and overriding up to 2 cm have been accepted. Posterior and anterior angulations have been rejected. After an average 4-year follow-up, neither joint stiffness nor skeletal deformity developed. At follow-up, maximal shortening was 0.8 cm, and overgrowth was 0.5 cm. Except for complicated cases, the use of this method is justified.

Bone Wires↗