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PubMed2006

Corticotropin-releasing hormone, its binding protein and receptors in human cervical tissue at preterm and term labor in comparison to non-pregnant state.

BACKGROUND: Preterm birth is still the leading cause of neonatal morbidity and mortality. The level of corticotropin-releasing hormone (CRH) is known to be significantly elevated in the maternal plasma at preterm birth. Although, CRH, CRH-binding protein (CRH-BP), CRH-receptor 1 (CRH-R1) and CRH-R2 have been identified both at mRNA and protein level in human placenta, deciduas, fetal membranes, endometrium and myometrium, no corresponding information is yet available on cervix. Thus, the aim of this study was to compare the levels of the mRNA species coding for CRH, CRH-BP, CRH-R1 and CRH-R2 in human cervical tissue and myometrium at preterm and term labor and not in labor as well as in the non-pregnant state, and to localize the corresponding proteins employing immunohistochemical analysis. METHODS: Cervical, isthmic and fundal (from non-pregnant subjects only) biopsies were taken from 67 women. Subjects were divided in 5 groups: preterm labor (14), preterm not in labor (7), term labor (18), term not in labor (21) and non-pregnant (7). Real-time RT-PCR was employed for quantification of mRNA levels and the corresponding proteins were localized by immunohistochemical analysis. RESULTS: The levels of CRH-BP, CRH-R1 and CRH-R2 mRNA in the pregnant tissues were lower than those in non-pregnant subjects. No significant differences were observed between preterm and term groups. CRH-BP and CRH-R2 mRNA and the corresponding proteins were present at lower levels in the laboring cervix than in the non-laboring cervix, irrespective of gestational age. In most of the samples, with the exception of four myometrial biopsies the level of CRH mRNA was below the limit of detection. All of these proteins could be detected and localized in the cervix and the myometrium by immunohistochemical analysis. CONCLUSION: Expression of CRH-BP, CRH-R1 and CRH-R2 in uterine tissues is down-regulated during pregnancy. The most pronounced down-regulation of CRH-BP and CRH-R2 occurred in laboring cervix, irrespective the length of gestation. The detection of substantial expression of the CRH and its receptor proteins, as well as receptor mRNA in the cervix suggests that the cervix may be a target for CRH action. Further studies are required to elucidate the role of CRH in cervical ripening.

Adolescent↗

PubMed2005

Palatal development of preterm and low birthweight infants compared to term infants - What do we know? Part 2: The palate of the preterm/low birthweight infant.

BACKGROUND: Well-designed clinical studies on the palatal development in preterm and low birthweight infants are desirable because the literature is characterized by contradictory results. It could be shown that knowledge about 'normal' palatal development is still weak as well (Part 1). The objective of this review is therefore to contribute a fundamental analysis of methodologies, confounding factors, and outcomes of studies on palatal development in preterm and low birthweight infants. METHODS: An electronic literature search as well as hand searches were performed based on Cochrane search strategies including sources of more than a century in English, German, and French. Original data were recalculated from studies which primarily dealt with both preterm and term infants. The extracted data, especially those from non-English paper sources, were provided unfiltered for comparison. RESULTS: Seventy-eight out of 155 included articles were analyzed for palatal morphology of preterm infants. Intubation, feeding tubes, feeding mode, tube characteristics, restriction of oral functions, kind of diet, cranial form and birthweight were seen as causes contributing to altered palatal morphology. Changes associated with intubation concern length, depth, width, asymmetry, crossbite, and contour of the palate. The phenomenon 'grooving' has also been described as a complication associated with oral intubation. However, this phenomenon suffers from lack of a clear-cut definition. Head flattening, pressure from the oral tube, pathologic or impaired tongue function, and broadening of the alveolar ridges adjacent to the tube have been raised as causes of 'grooving'. Metrically, the palates of intubated preterm infants remain narrower, which has been examined up to the age of the late mixed dentition. CONCLUSION: There is no evidence that would justify the exclusion of any of the raised causes contributing to palatal alteration. Thus, early orthodontic and logopedic control of formerly orally intubated preterm infants is recommended, as opposed to non-intubated infants. From the orthodontic point of view, nasal intubation should be favored. The role that palatal protection plates and pressure-dispersing pads for the head have in palatal development remains unclear.

Humans↗

PubMed2003

Formula feeding potentiates docosahexaenoic and arachidonic acid biosynthesis in term and preterm baboon neonates.

Infant formulas supplemented with docosahexaenoic acid (DHA) and arachidonic acid (ARA) are now available in the United States; however, little is known about the factors that affect biosynthesis. Baboon neonates were assigned to one of four treatments: term, breast-fed; term, formula-fed; preterm (155 of 182 days gestation), formula-fed; and preterm, formula+DHA/ARA-fed. Standard formula had no DHA/ARA; supplemented formula had 0.61%wt DHA (0.3% of calories) and 1.21%wt ARA (0.6% of calories), and baboon breast milk contained 0.68 +/- 0.22%wt DHA and 0.62 +/- 0.12%wt ARA. At 14 days adjusted age, neonates received a combined oral dose of [U-13C]alpha-linolenic acid (LNA*) and [U-13C]linoleic acid (LA*), and tissues were analyzed 14 days after dose. Brain accretion of linolenic acid-derived DHA was approximately 3-fold greater for the formula groups than for the breast-fed group, and dietary DHA partially attenuated excess DHA synthesis among preterms. A similar, significant pattern was found in other organs. Brain linoleic acid-derived ARA accretion was significantly greater in the unsupplemented term group but not in the preterm groups compared with the breast-fed group. These data show that formula potentiates the biosynthesis/accretion of DHA/ARA in term and preterm neonates compared with breast-fed neonates and that the inclusion of DHA/ARA in preterm formula partially restores DHA/ARA biosynthesis to lower, breast-fed levels. Current formula DHA concentrations are inadequate to normalize long-chain polyunsaturated fatty acids synthesis to that of breast-fed levels.

Animal Feed↗

PubMed2005

Human decidual relaxin and preterm birth.

Relaxin in human pregnancy is both a systemic hormone from the corpus luteum and an autocrine/paracrine hormone at the maternal-fetal interface formed by the decidua/placenta and fetal membranes. We have focused our studies on the autocrine/paracrine roles of relaxin, especially in the preterm premature rupture of the fetal membranes, which causes 30-40% of preterm births. By using different techniques and different tissue collections, our laboratory has shown that expression of the relaxin genes and proteins in the decidua and placenta is increased in patients with preterm premature rupture of the fetal membranes. Relaxin binding and the expression of LGR7 are primarily in the chorion and decidua and are downregulated after spontaneous labor and delivery both at term and preterm. However, expression of LGR7 in the fetal membranes is significantly greater in all clinical situations at preterm than term, suggesting an important role for relaxin in these tissues at that time. The roles of the relaxin system in three potential causes of preterm birth are discussed: in the growth and proliferation of the membranes important for fetal membrane accommodation to fetal and placental growth, in acute infection, and in the inflammatory response leading to the initiation of labor.

Cell Proliferation↗

PubMed1987

A developmental study on types and frequency distribution of short apneas (3 to 15 seconds) in term and preterm infants.

We measured the frequency distribution and the ventilatory correlates of the various types of apneas 3 to 15 s long during sleep in eight term infants (birth weight 3.65 +/- 0.16 kg; gestational age 39.5 +/- 0.3 wk) and eight preterm infants (birth weight 2.07 +/- 0.18 kg; gestational age 34.3 +/- 0.4 wk). Each infant was studied on five to seven occasions from birth to 56 wk of postconceptual age using a modified flow-through system. Sixty-six paired epochs of quiet sleep (1163 min) and rapid eye movement sleep (829 min) were analyzed in term infants and 85 paired epochs of quiet sleep (1553 min) and rapid eye movement sleep (1328 min) in preterm infants. Of the 783 apneas recorded in term infants 82% were central, 1.5% obstructive, 0.5% mixed, and 16% were of the breath-holding type; the corresponding figures for the 4086 apneas recorded in preterm infants were 93, 0.5, 1.0, and 5.5%. This distribution was similar in the two sleep states but term infants had a higher percentage of breath-holding apneas than preterm infants (p less than 0.01). In preterm infants the rate of central apneas decreased with postnatal age (p less than 0.01); in term infants the rate did not change significantly. The duration of apneas showed a modal distribution for central apneas at about 8 s for both groups during the 1st month of life (p less than 0.05). The findings suggest: 1) apneas in the newborn and early infancy are primarily central and are more frequent in preterm than in term infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Apnea↗

PubMed1988

Ophthalmic artery blood flow velocity in healthy term and preterm neonates.

Ophthalmic artery blood flow velocity (OA-BFV, cm/s), cerebral blood flow velocity (C-BFV, cm/s), and cardiac output (ml/min) were measured by pulsed Doppler sonography in 15 healthy term and 10 well preterm (26-35 wk) infants in the first week of life. OA-BFV did not increase with increasing gestational age (preterm: peak systolic BFV 29 +/- 5 cm/s, mean BFV 7.2 +/- 1.5 cm/s; term: peak systolic BFV 27 +/- 5 cm/s, mean BFV 6.6 +/- 1.3 cm/s), unlike C-BFV (preterm: peak systolic BFV 34 +/- 8 cm/s, mean BFV 9.4 +/- 2.3 cm/s; term: peak systolic BFV 43 +/- 9 cm/s, p less than 0.05; mean BFV 11 +/- 3.0 cm/s, p less than 0.05) and cardiac output (preterm 329 +/- 128 ml/min, term 732 +/- 112 ml/min; p less than 0.001). The ratio of OA-BFV/C-BFV was significantly higher in preterm than in term infants (p less than 0.01). In preterm infants, but not in term infants, there was a positive linear correlation of OA-BFV to C-BFV (r = 0.88). We conclude that it is possible to measure opthalmic artery blood flow velocity in neonates by pulsed Doppler sonography. Gestational age has different effects on OA-BFV and on C-BFV. Although it is a point of discussion if blood flow velocities are reflecting absolute blood flow, Doppler assessment of OA-BFV could be a tool for monitoring risk factors for retinopathy of prematurity.

Blood Flow Velocity↗

PubMed1990

Estimation of extracellular volume in preterm infants less than 1500 g, children, and adults by sucrose dilution.

Extracellular volume can be estimated from the distribution volume of sucrose (Vdsucrose). The purpose of this study was to establish sucrose pharmacokinetics in preterm infants less than 1500 g compared to children and adults and to define an optimal sampling scheme. In five preterm infants, 10 children, and five adults Vdsucrose after a single injection was calculated with the two-compartment model (Vdsucrose-TCM) and with the one-compartment model applied only to the elimination phase of the same concentration-time curve (Vdsucrose-OCM). In preterm infants Vdsucrose-TCM was 417 +/- 45 mL/kg (mean +/- SD). Vdsucrose-OCM was only 3.0 +/- 2.3% higher, because sucrose elimination half-life was on average 250 times longer than distribution half-life. Therefore Vdsucrose-OCM, requiring only four blood samples between 2 to 5 h after injection, gave an adequate estimate of Vdsucrose in preterm infants less than 1500 g. Vdsucrose-TCM in children and adults was 188 +/- 26 and 189 +/- 17 mL/kg, respectively. Vdsucrose-OCM was 10 to 65% higher. Therefore, in children and adults only Vdsucrose-TCM gives a reliable estimate of Vdsucrose. This requires 10 to 15 blood samples. The reduced sampling scheme was used in an extension of the study of preterm infants including five additional infants. Vdsucrose-OCM in the preterm infants was 462 +/- 47 mL/kg at birth and 425 +/- 46 mL/kg at maximal postnatal wt loss. Postnatal wt loss (mean -83 +/- 44 g) was not significantly different from postnatal reduction of Vdsucrose-OCM (mean -82 +/- 56 mL), suggesting that postnatal wt loss mainly represents extracellular fluid loss.

Adolescent↗

PubMed1999

Bone turnover in preterm infants.

Total parenteral nutrition is associated with osteopenia in preterm infants. Insufficient calcium and phosphate are likely causes: aluminum contamination is another possible contributing factor as this adversely affects bone formation and mineralization. The study was designed to evaluate changes in biochemical markers of bone turnover in 22 preterm infants receiving total parenteral nutrition in comparison with 19 term infants. We collected urine and serum samples from 22 preterm infants, mean gestational age 29 wk, within 48 h and again at 3 wk of life. We also collected urine samples from 19 term infants, mean gestational age 39 wk, during the first day of life. Bone resorption was assessed by the measurement of urinary pyridinium cross-links by HPLC and ELISA and the N-telopeptide of type I collagen by ELISA. Bone formation was assessed in premature infants by the measurement of serum osteocalcin. The N-telopeptide of type I collagen was higher in the preterm infants compared with term at baseline (p < 0.01). There was no difference between the pyridinium cross-links in the preterm and term infants. All the biochemical markers of bone turnover increased significantly in the preterm infants during the first 3 wk of life, e.g. N-telopeptide was a 153% change from baseline (p < 0.001). Aluminum in the total parenteral nutrition solutions did not cause a decrease in bone formation at the level administered (3-6 microg, 0.1-0.2 micromol x kg(-1) x d(-1)).

Bone Diseases, Metabolic↗

PubMed2001

Lipopolysaccharide-induced tumor necrosis factor-alpha and IL-10 production by lung macrophages from preterm and term neonates.

Lung injury in preterm neonates with respiratory failure has been attributed to persistent inflammation, which is likely to involve lung macrophages (LM). The study objective was to investigate LM during the first 8 d of life from preterm infants (n = 19), using term infants (n = 11) with respiratory failure as control subjects. LM percentages from mixed-cell suspensions produced from tracheobronchial lavage were calculated. A postnatal increase in the mean LM concentration was demonstrated within the preterm group (p = 0.01), which was greater in comparison to that from the term group (p < 0.01). Regression analyses were significant for direct relationships between LM concentrations and ex vivo lipopolysaccharide-induced tumor necrosis factor-alpha and IL-10 production (r = 0.93 and r = 0.63, respectively), establishing LM as the source of these cytokines. Comparative analyses demonstrated that the ability of preterm versus term LM to produce tumor necrosis factor-alpha was nearly identical; in contrast, a trend toward diminished levels of IL-10 expression in the preterm group was observed (p = 0.06). Thus, although studies have shown that LM precursors (i.e. cord blood monocytes) produce less tumor necrosis factor-alpha in preterm versus term infants, the present data strongly suggest that this relationship does not hold postnatally with respect to terminally differentiated LM in sick neonates. Overall, the data are consistent with a pro- versus antiinflammatory imbalance that may bear functional significance on the pathogenesis of chronic lung disease.

Humans↗

PubMed2002

Oxidative stress in preterm rat brain is due to mitochondrial dysfunction.

Prematurity-mediated cerebral damage has been associated with oxidative stress. The aim of the present work was to study the possible role played by free oxygen radicals generated by mitochondrial respiratory function in cerebral injury in preterm neonates. Our results show that whereas total glutathione concentrations are similar in term and preterm neonates, the GSH/GSSG ratio decreases sharply in preterm neonates immediately after birth. This effect is not due to a lack of enzymes involved in GSH regeneration, such as glutathione reductase and glucose-6-phosphate dehydrogenase, but to a significant increase in free-radical generation in preterm rat brain as shown by the increase in lipoperoxidation. Because the mitochondrion is the main source of free radicals in the cell, mitochondrial respiratory function was studied in the brain of preterm neonates. Our results show that prematurity prevented the postnatal increases in complex II-III activity and ATP concentrations that occur in term neonates at 5 min after delivery. All these effects were counteracted by the oxygen supply, suggesting that the inhibition of mitochondrial function is caused by restricted oxygen availability. Consequently, cerebral damage associated with prematurity may be mediated by mitochondrial free-radical generation as a consequence of hypoxia undergone by preterm neonates at birth.

Animals↗

PubMed2002

Oxidative stress in preterm neonates at birth and on the seventh day of life.

Previous studies have demonstrated increased oxidative damage to proteins and increased lipid peroxidation products in the plasma of hypoxic newborns at birth. We tested the hypothesis that hypoxic preterm newborns are at increased risk for oxidative stress in the first week of life. Heparinized blood samples of 34 hypoxic and 15 control preterm newborns were obtained at birth from the umbilical vein immediately after delivery and from a peripheral vein on postnatal d 7. Plasma levels of hypoxanthine, total hydroperoxide (TH), and advanced oxidation protein products (AOPP) were measured in cord blood and blood drawn on d 7. Hypoxanthine, TH, and AOPP levels were significantly higher in cord and d 7 blood samples of hypoxic newborn than control infants. Statistically significant correlations were observed between AOPP and hypoxanthine and between AOPP and TH plasma levels on d 7. AOPP and TH plasma levels significantly increased from cord to d 7 blood in neonates without hypoxia. These findings show that the oxidative stress observed in cord blood of hypoxic preterm newborns is still higher than control infants on d 7. The significant increase in TH and AOPP levels in nonhypoxic preterm newborns at the end of the first postnatal week indicates that damage caused by free radicals also occurs in nonhypoxic babies with normal clinical course. In summary, TH and AOPP production is prolonged for several days after birth in hypoxic preterm babies. The risk of free radical damage is lower but still exists in preterm neonates with normal clinical course.

Age Factors↗

PubMed2002

Maturity of the adrenal cortex in very preterm infants is related to gestational age.

To study the maturity of the adrenal cortex in preterms born before 33 wk of gestation, basal levels of cortisol and cortisone and the cortisol and 17-hydroxyprogesterone (17-OHP) response to 1 microg/kg adrenocorticotropic hormone stimulation were measured in 24 appropriate-for-gestational age preterm infants (26-33 wk; 690-1985 g). Gestational age influenced the response of cortisol, 17-OHP, and the ratio between cortisol/17-OHP in the studied infants. In preterms born <30 wk of gestation, levels of cortisol, and the ratio between cortisol/17-OHP were lower compared with preterms born between 30 and 33 wk. Levels of cortisone were higher in preterms born <30 wk, suggesting a lower activity of 11 beta-hydroxysteroid dehydrogenase that may be related to maturity as well. These findings indicate that the adrenal cortex function in preterm infants is closely related to the duration of gestation and may be important in neonatal morbidity.

17-alpha-Hydroxyprogesterone↗

PubMed2005

Bacteria and inflammatory cells in fetal membranes do not always cause preterm labor.

Intrauterine infection has been frequently linked with preterm labor before 30 wk of human pregnancy. Many different species of organisms have been detected, leading to the suggestion that infection-induced preterm labor is a generic inflammatory response to organisms rather than a specific response to a limited number of pathogens. The detection of organisms by microbiological culture is a laborious and unreliable process, so the aim of this study was to harness modern molecular techniques to detect organisms in tissues from human pregnancy. A DNA probe specific for conserved regions of bacterial 16S ribosomal RNA sequence was designed and labeled with fluorescein for fluorescence in situ hybridization. Organisms were detected in the great majority (>80%) of fetal membranes after prolonged premature rupture of the fetal membranes and after preterm labor, which was consistent with previous data. Organisms were also detected in fetal membranes after preterm delivery without labor and in term deliveries (with or without labour). Inflammatory cells were found frequently in the amnion or chorion of preterm fetal membranes but not in term tissues. Our primary finding is that fluorescence in situ hybridization is an appropriate method to detect organisms in human fetal membranes. In addition, our data show that bacteria may be present in fetal membranes without necessarily causing an inflammatory response, so the mere presence of bacteria may not be sufficient to cause preterm labor.

Antigens, CD↗

PubMed2005

Brainstem auditory function at term in preterm babies with and without perinatal complications.

Functional integrity of the auditory brainstem was studied at term in babies born at 30-36 wk of gestation using maximum length sequence brainstem auditory evoked response (MLS BAER). Compared with normal term babies, preterm babies who had perinatal complications showed a tendency of an increase in wave V latency and I-V and III-V intervals at all 91-910/s clicks, with statistical significance at higher rates. Wave V latency and I-V interval increased significantly at 455/s and 910/s. III-V interval increased at all click rates, which was more significant at higher rates. III-V/I-III interval ratio increased at most rates. Waves III and V amplitudes reduced significantly mainly at 455/s and 910/s. In preterm babies who had no perinatal complications, there were no major MLS BAER abnormalities except an increase in III-V interval at 91-910/s. By comparison, the preterm babies with perinatal complications had a significant increase in wave V latency, I-V and III-V intervals, and III-V/I-III interval ratio at 455/s and 910/s clicks. These results suggest that although there are no major abnormalities in brainstem auditory function in preterm babies without perinatal complications, the auditory brainstem, mainly the more central part, in preterm babies with perinatal complications is impaired, which becomes more apparent at very high stimulus rates. We conclude that preterm babies with perinatal complications are at high risk of central auditory impairment.

Brain Stem↗

PubMed2006

Reduction in cerebellar volumes in preterm infants: relationship to white matter injury and neurodevelopment at two years of age.

A substantial number of prematurely born infants will experience later neurodevelopmental challenges. Abnormal development of the cerebellum may be related to some of the impairments exhibited by preterm children. To test the hypothesis that cerebellar development is structurally impaired in preterm infants and associated with adverse outcomes, we studied 83 preterm infants and 13 term controls using volumetric magnetic resonance imaging techniques to obtain cerebellar volumes (CV) at term corrected and subsequent neurodevelopmental assessment at 2 y of age. The preterm group had smaller mean CV at term compared with the term control infants [mean (SD) CV, 22.0 (5.0) versus 23.5 (5.0) cc; mean difference (95% confidence interval), 1.5 (-1.5, 4.4)] although this did not reach statistical significance. Within the preterm group, there was evidence of a reduction in CV related to the presence of white matter injury (WMI) after adjusting for intracranial volume (ICV) [WMI grade 1 versus grade 2: mean (SD) CV, 23.6 (5.0) versus 21.6 (4.5); p = 0.01; WMI grade 1 versus grade 3 and 4: 23.6 (5.0) versus 20.8 (5.6); p = 0.07]. Within the preterm infants, there was no apparent relationship between CV at term and gestational age at birth after adjusting for ICV. At 2 y of age, CV showed a weak correlation with cognitive and motor development, although this was principally mediated by WMI. In conclusion, we found no evidence for a primary impairment in cerebellar development in relation to prematurity, although there was evidence for a secondary effect of cerebral WMI on cerebellar development independent of immaturity.

Aging↗

PubMed2006

Noninvasive measurements of regional cerebral perfusion in preterm and term neonates by magnetic resonance arterial spin labeling.

Magnetic resonance arterial spin labeling (ASL) at 3 Tesla has been investigated as a quantitative technique for measuring regional cerebral perfusion (RCP) in newborn infants. RCP values were measured in 49 healthy neonates: 32 preterm infants born before 34 wk of gestation and 17 term-born neonates. Examinations were performed on unsedated infants at postmenstrual age of 39-40 wk in both groups. Due to motion, reliable data were obtained from 23 preterm and 6 term infants. Perfusion in the basal ganglia (39 and 30 mL/100 g/min for preterm and term neonates, respectively) was significantly higher (p < 0.0001) than in cortical gray matter (19 and 16 mL/100 g/min) and white matter (15 and 10 mL/100 g/min), both in preterm neonates at term-equivalent age and in term neonates. Perfusion was significantly higher (p = 0.01) in the preterm group than in the term infants, indicating that RCP may be influenced by developmental and postnatal ages. This study demonstrates, for the first time, that noninvasive ASL at 3T may be used to measure RCP in healthy unsedated preterm and term neonates. ASL is, therefore, a viable tool that will allow serial studies of RCP in high-risk neonates.

Cerebrovascular Circulation↗

PubMed1994

Differential cyclooxygenase-1 and -2 gene expression in human myometria from preterm and term deliveries.

The expression of cyclooxygenase-1 (COX-1) and COX-2 genes in myometria from preterm and term pregnancies was investigated by in situ hybridization, immunoblotting, and immunocytochemistry. In situ hybridization revealed that myometrial smooth muscle contained both COX-1 and COX-2 messenger ribonucleic acid transcripts. Immunoblotting revealed that myometria contained 55- and 67-kilodalton COX-1 proteins as well as 72- and 56-kilodalton COX-2 proteins. Immunocytochemistry showed that COX-1 and COX-2 proteins are present in the myometrial smooth muscle. The expression of COX-1 and COX-2 genes differed in myometria. For example, although COX-1 expression was lower, COX-2 expression was higher at term compared to preterm pregnancy not in labor. In addition, although COX-1 expression was not dependent on labor, COX-2 expression was lower with labor compared to not in labor for both preterm and term pregnancy. The myometrial smooth muscle also immunostained for prostaglandin E2 (PGE2) and PGF2 alpha, suggesting that the cyclooxygenases are catalytically active. The changes in PGE2 and PGF2 alpha paralleled the changes in COX-1 enzyme in terms of being lower at term compared to preterm pregnancy and the changes in COX-2 enzyme in terms of being lower during labor at preterm and term pregnancy. In summary, our results demonstrate that pregnant human myometria express both COX-1 and COX-2 genes. The expression of these genes differed in preterm or term pregnancy myometria from in labor and not in labor.

Dinoprost↗

PubMed2004

Heparinase-modified thrombelastography in term and preterm neonates.

UNLABELLED: Thrombelastography (TEG) appears to be a promising test to assess coagulation in infants and children. TEG enables a rapid assessment of hemostatic function with only 300 microL of whole blood and provides information about plasmatic coagulation, platelet function, and fibrinolysis. In this study, we used TEG to assess the coagulation system of preterm and term neonates to determine the effects of their deficient coagulation factor levels on global hemostatic function. Heparinase-modified TEG, platelet and red blood cell count, plasma fibrinogen, and prothrombin time were assessed in four groups of clinically stable infants: severely preterm (gestational age [GA], 27-31 wk), moderately preterm (GA, 32-36 wk), term (GA, 36-40 wk), and former preterm (corrected GA, 34-40 wk). Healthy adult volunteers served as a control group. When compared with the adult group, thromboelastography revealed no defects in coagulation from groups of clinically stable infants, documenting the functional integrity of coagulation despite, in part, decreased conventional coagulation variables. Because clinically stable preterm and term infants show a relatively small incidence of bleeding, despite prolonged conventional coagulation tests, TEG may better reflect the hemostatic potential of these patients compared with conventional coagulation tests. IMPLICATIONS: This study assessed the coagulation of preterm and term infants by thrombelastography and found functional integrity of coagulation despite, in part, decreased conventional coagulation variables.

Adult↗