Exploring the health care utilization of children and youth in the care of child welfare: a retrospective matched cohort study.

BACKGROUND: Children and youth whose lives intersect with child welfare systems are amongst the most vulnerable paediatric populations. Despite the increased rates of chronic conditions, these children and youth often experience unmet health care needs. OBJECTIVES: To examine patterns of health care utilization from birth for children and youth in the care of a child welfare authority. METHODS: This retrospective matched cohort design study examined children/youth aged 0-18 who had visited a paediatric tertiary care facility from 2016 April 1 to 2017 March 31 and had "social worker" documented as their guardian. A control cohort was matched based on age and sex. Primary outcomes of interest included primary health care, emergency, outpatient, and inpatient visits. Visits for immunizations, physiological development, well-baby checks, mental health, and oral health were also examined. RESULTS: A total of 200 cases and 200 controls were included in our cohort. No statistically significant differences were found between primary care visits, well-baby checks, inpatient admissions, outpatient mental health visits, or immunizations for children in care in comparison to their controls. There was a significant difference in oral health visits, lack of physiological development, and emergency department visits for children in care when compared to their controls. CONCLUSIONS: Our study revealed disparities in health care utilization amongst children in the care of child welfare in comparison to those who are not, highlighting the need for improved practice, policy, and research initiatives. A collaborative data collection/sharing system is needed to identify and track the health care of this vulnerable population.

Children and youth whose lives intersect with child welfare systems are amongst the most vulnerable pediatric populations. Despite the increased rates of chronic health conditions, these children and youth often experience unmet health care needs. Using a retrospective matched cohort design, we sought to examine patterns of health care utilization from birth to age 18 for children and youth in the care of a child welfare authority in comparison to children/youth who were not in the care of child welfare. No statistically significant differences were found between primary care visits, well-baby checks, inpatient admissions, outpatient mental health visits, or immunizations for children in care when compared to their counterparts not in care. There was a significantly higher number of oral health visits, physiological development concerns, and emergency department visits for children in care when compared to their controls. Our study revealed differences in health care use amongst children in the care of a child welfare in comparison to those who are not, highlighting the need for improved practice, policy and research initiatives. A collaborative data collection and sharing system is needed to help accurately identify and track the health care use of this vulnerable population.

Genes upregulated in the amnion at labour are bivalently marked by activating and repressive histone modifications.

Inflammatory genes are expressed increasingly in the foetal membranes at late gestation triggering birth. Here we have examined whether epigenetic histone modifications contribute to the upregulation of proinflammatory genes in the amnion in late pregnancy and at labour. Amnion samples were collected from early pregnancy, at term in the absence of labour and after spontaneous birth. The expression of the labour-associated proinflammatory genes PTGS2, BMP2 and NAMPT was determined by reverse transcription-coupled quantitative real-time PCR (qRT-PCR). Chromatin immunoprecipitation (ChIP) and sequential double ChIP were performed to determine the levels and co-occurrence of activating histone-3, lysine-4 trimethylation (H3K4me3) and repressive histone-3, lysine-27 trimethylation (H3K27me3) at the gene promoters. H3K4 methyltransferase, H3K27me3 demethylase and H3K27 methyltransferase expression was determined by qRT-PCR and immunofluorescence confocal microscopy. PTGS2, BMP2 and NAMPT expression was upregulated robustly between early pregnancy and term (P < 0.05). The promoters were marked bivalently by both the H3K4me3 and H3K27me3 modifications. Bivalence was reduced at term by the decrease of the H3K27me3-modified fraction of promoter copies marked by H3K4me3 indicating epigenetic activation. Messenger RNAs encoding the H3K4-specific methyl transferases MLL1,-2,-3,-4, SETD1A,-B and the H3K27me3-specific demethylases KDM6A,-B were expressed increasingly while the H3K27 methyl transferase EZH2 was expressed decreasingly at term. Histone modifying enzyme proteins were detected in amnion epithelial and mesenchymal cells. These results with prototypical proinflammatory genes suggest that nucleosomes at labour-promoting genes are marked bivalently in the amnion, which is shifted towards monovalent H3K4me3 modification at term when the genes are upregulated. Bivalent epigenetic regulation by histone modifying enzymes may control the timing of labour.

Plant Defense against Herbivorous Pests: Exploiting Resistance and Tolerance Traits for Sustainable Crop Protection.

Interactions between plants and insect herbivores are important determinants of plant productivity in managed and natural vegetation. In response to attack, plants have evolved a range of defenses to reduce the threat of injury and loss of productivity. Crop losses from damage caused by arthropod pests can exceed 15% annually. Crop domestication and selection for improved yield and quality can alter the defensive capability of the crop, increasing reliance on artificial crop protection. Sustainable agriculture, however, depends on reduced chemical inputs. There is an urgent need, therefore, to identify plant defensive traits for crop improvement. Plant defense can be divided into resistance and tolerance strategies. Plant traits that confer herbivore resistance typically prevent or reduce herbivore damage through expression of traits that deter pests from settling, attaching to surfaces, feeding and reproducing, or that reduce palatability. Plant tolerance of herbivory involves expression of traits that limit the negative impact of herbivore damage on productivity and yield. Identifying the defensive traits expressed by plants to deter herbivores or limit herbivore damage, and understanding the underlying defense mechanisms, is crucial for crop scientists to exploit plant defensive traits in crop breeding. In this review, we assess the traits and mechanisms underpinning herbivore resistance and tolerance, and conclude that physical defense traits, plant vigor and herbivore-induced plant volatiles show considerable utility in pest control, along with mixed species crops. We highlight emerging approaches for accelerating the identification of plant defensive traits and facilitating their deployment to improve the future sustainability of crop protection.

Methylation of promoter regions of genes of the human intrauterine Renin Angiotensin system and their expression.

The intrauterine renin angiotensin system (RAS) is implicated in placentation and labour onset. Here we investigate whether promoter methylation of RAS genes changes with gestation or labour and if it affects gene expression. Early gestation amnion and placenta were studied, as were term amnion, decidua, and placenta collected before labour (at elective caesarean section) or after spontaneous labour and delivery. The expression and degree of methylation of the prorenin receptor (ATP6AP2), angiotensin converting enzyme (ACE), angiotensin II type 1 receptor (AGTR1), and two proteases that can activate prorenin (kallikrein, KLK1, and cathepsin D, CTSD) were measured by qPCR and a DNA methylation array. There was no effect of gestation or labour on the methylation of RAS genes and CTSD. Amnion and decidua displayed strong correlations between the percent hypermethylation of RAS genes and CTSD, suggestive of global methylation. There were no correlations between the degree of methylation and mRNA abundance of any genes studied. KLK1 was the most methylated gene and the proportion of hypermethylated KLK1 alleles was lower in placenta than decidua. The presence of intermediate methylated alleles of KLK1 in early gestation placenta and in amnion after labour suggests that KLK1 methylation is uniquely dynamic in these tissues.

Effects of Fetal Sex on Expression of the (Pro)renin Receptor and Genes Influenced by its Interaction With Prorenin in Human Amnion.

Males are more likely to be born preterm than females. The causes are unknown, but it is suggested that intrauterine tissues regulate fetal growth and survival in a sex-specific manner. We postulated that prorenin binding to its prorenin/renin receptor receptor (ATP6AP2) would act in a fetal sex-specific manner in human amnion to regulate the expression of promyelocytic zinc finger, a negative regulator of ATP6AP2 expression as well as 2 pathways that might influence the onset of labor, namely transforming growth factor ß1 (TGFB1) and prostaglandin endoperoxide synthase 2 (PTGS2). Our findings demonstrate that there are strong interactions between prorenin, ATP6AP2, and TGFB1 and that this system has a greater capacity in female amnion to stimulate profibrotic pathways, thus maintaining the integrity of the fetal membranes. In contrast, glucocorticoids or other factors independent of the prorenin/prorenin receptor pathway may be important regulators of PTGS2 in human pregnancy.

Downstairs drivers--root herbivores shape communities of above-ground herbivores and natural enemies via changes in plant nutrients.

1. Terrestrial food webs are woven from complex interactions, often underpinned by plant-mediated interactions between herbivores and higher trophic groups. Below- and above-ground herbivores can influence one another via induced changes to a shared host plant, potentially shaping the wider community. However, empirical evidence linking laboratory observations to natural field populations has so far been elusive. 2. This study investigated how root-feeding weevils (Otiorhynchus sulcatus) influence different feeding guilds of herbivore (phloem-feeding aphids, Cryptomyzus galeopsidis, and leaf-chewing sawflies, Nematus olfaciens) in both controlled and field conditions. 3. We hypothesized that root herbivore-induced changes in plant nutrients (C, N, P and amino acids) and defensive compounds (phenolics) would underpin the interactions between root and foliar herbivores, and ultimately populations of natural enemies of the foliar herbivores in the field. 4. Weevils increased field populations of aphids by ca. 700%, which was followed by an increase in the abundance of aphid natural enemies. Weevils increased the proportion of foliar essential amino acids, and this change was positively correlated with aphid abundance, which increased by 90% on plants with weevils in controlled experiments. 5. In contrast, sawfly populations were 77% smaller during mid-June and adult emergence delayed by >14 days on plants with weevils. In controlled experiments, weevils impaired sawfly growth by 18%, which correlated with 35% reductions in leaf phosphorus caused by root herbivory, a previously unreported mechanism for above-ground-below-ground herbivore interactions. 6. This represents a clear demonstration of root herbivores affecting foliar herbivore community composition and natural enemy abundance in the field via two distinct plant-mediated nutritional mechanisms. Aphid populations, in particular, were initially driven by bottom-up effects (i.e. plant-mediated effects of root herbivory), but consequent increases in natural enemies triggered top-down regulation.

Inflammatory and steroid receptor gene methylation in the human amnion and decidua.

Correct timing of parturition requires inflammatory gene activation in the gestational tissues at term and repression during pregnancy. Promoter methylation at CpG dinucleotides represses gene activity; therefore, we examined the possibility that DNA methylation is involved in the regulation of labour-associated genes in human pregnancy. Amnion and decidua were collected at 11-17 weeks of gestation and at term following elective Caesarean delivery or spontaneous labour. Methylation of the inflammatory genes PTGS2, BMP2, NAMPT and CXCL2 was analysed using the Methyl-Profiler PCR System and bisulphite sequencing. Methylation of the glucocorticoid, progesterone and oestrogen receptor genes, involved in the hormonal regulation of gestational tissue function, and the expression of the DNA methyltransferases DNMT1, -3A and -3B were also determined. Variable proportions of inflammatory and steroid receptor gene copies, to a maximum of 50.9%, were densely methylated in both tissues consistent with repression. Densely methylated copy proportions were significantly different between genes showing no relationship with varying expression during pregnancy, between tissues and in individuals. Methylated copy proportions of all genes in amnion and most genes in decidua were highly correlated in individuals. DNMT1 and -3A were expressed in both tissues with significantly higher levels in the amnion at 11-17 weeks than at term. We conclude that the unmethylated portion of gene copies is responsible for the full range of regulated expression in the amnion and decidua during normal pregnancy. Dense methylation of individually variable gene copy proportions happens in the first trimester amnion influenced by sequence context and affected strongly by individual circumstances.

Uptake and continuation rates of the intrauterine system in a university student general practice population in the UK.

OBJECTIVE: To follow a series of 100 women attending for fitting of the levonorgestrel-releasing intrauterine system (LNG IUS) registered at a single urban general practice serving the students of the local universities and higher education colleges. METHODS: This was a prospective observational study. A questionnaire was completed by the fitter in discussion with the patient at the time of attendance for IUS fitting. Follow up was by telephone at 6 weeks, 6 months and 9-12 months after fitting. RESULTS: The age range of women within the series was 18-38 years. 97 women were nulliparous. 37 women selected the IUS as their preferred method of contraception. 12 women chose the IUS primarily for non-contraceptive reasons. 75 women still had the IUS at 12 months' follow up with 11 lost to follow up at this point. No pregnancies or perforations were reported. CONCLUSIONS: The IUS is an acceptable form of contraception in young women, including nulliparous women, and should be offered alongside other methods as first line without restriction when offering contraceptive options to this age group.

Raspberry leaf blotch virus, a putative new member of the genus Emaravirus, encodes a novel genomic RNA.

A new, segmented, negative-strand RNA virus with morphological and sequence similarities to other viruses in the genus Emaravirus was discovered in raspberry plants exhibiting symptoms of leaf blotch disorder, a disease previously attributed to the eriophyid raspberry leaf and bud mite (Phyllocoptes gracilis). The virus, tentatively named raspberry leaf blotch virus (RLBV), has five RNAs that each potentially encode a single protein on the complementary strand. RNAs 1, 2 and 3 encode, respectively, a putative RNA-dependent RNA polymerase, a glycoprotein precursor and the nucleocapsid. RNA4 encodes a protein with sequence similarity to proteins of unknown function that are encoded by the genomes of other emaraviruses. When expressed transiently in plants fused to green or red fluorescent protein, the RLBV P4 protein localized to the peripheral cell membrane and to punctate spots in the cell wall. These spots co-localized with GFP-tagged tobacco mosaic virus 30K cell-to-cell movement protein, which is itself known to associate with plasmodesmata. These results suggest that the P4 protein may be a movement protein for RLBV. The fifth RLBV RNA, encoding the P5 protein, is unique among the sequenced emaraviruses. The amino acid sequence of the P5 protein does not suggest any potential function; however, when expressed as a GFP fusion, it localized as small aggregates in the cytoplasm near to the periphery of the cell.

PTGS2 (prostaglandin endoperoxide synthase-2) expression in term human amnion in vivo involves rapid mRNA turnover, polymerase-II 5'-pausing, and glucocorticoid transrepression.

The in vivo role of glucocorticoids in controlling prostaglandin endoperoxide synthase-2 (PTGS2) expression in the human amnion is unclear despite extensive studies using in vitro models. We addressed this issue by determining PTGS2 mRNA levels and gene transcriptional activity, RNA polymerase-II (pol-II) binding, pol-II C-terminal domain (CTD) phosphorylation, histone acetylation, and histone methylation at the PTGS2 gene in fresh amnion and in amnion explants incubated with dexamethasone for 24 h after delivery, when adaptation from in vivo to in vitro conditions occurred. PTGS2 mRNA turnover changed during incubation involving the initial rapid decrease and subsequent rebound of the transcription rate and stabilization of mRNA. pol-II accumulated in the 5'-region of the gene, which indicated postinitiation pausing. pol-II binding, 5'-accumulation, C-terminal domain Ser-5 and Ser-2 phosphorylation, and histone acetylation decreased rapidly and did not reverse during the transcriptional rebound, suggesting that the transcriptional mechanism altered in vitro. Dexamethasone decreased PTGS2 gene activity and mRNA levels. Glucocorticoid receptor-α (GRα) was bound to the PTGS2 promoter but did not affect pol-II recruitment, pausing, or the epigenetic marks. GRα binding, however, decreased initiating (Ser-5) and elongating (Ser-2) pol-II phosphorylation. The ability of the PTGS2 promoter to bind GRα in response to dexamethasone diminished during incubation. We conclude that PTGS2 mRNA turnover is accelerated in vivo, but the underlying mechanisms are not sustained beyond 24 h in explants. Glucocorticoids chronically transrepress PTGS2 gene activity in vivo in part by interfering with transcription initiation and elongation. Glucocorticoid transrepression of PTGS2 may be important for pregnancy maintenance and the timing of parturition.

Molecular evidence of a (pro)renin/ (pro)renin receptor system in human intrauterine tissues in pregnancy and its association with PGHS-2.

Prorenin stimulates decidual prostaglandin (PG) production in vitro, the (pro)renin receptor ((P)RR) may mediate this action. The role of prorenin in amnion PG synthesis has not been examined, despite this being the key site of PG synthesis. To determine if (P)RR, prorenin and PGHS-2 are co-localized in gestational tissues and if expression is altered by labour, term amnion, chorion, decidua and placenta were collected during elective caesarean section or after spontaneous labour. Prorenin, (P)RR and PGHS-2 mRNA abundance was determined by real-time RT-PCR. (P)RR protein was examined by immunohistochemistry. The effect of recombinant human (rh) prorenin on PGHS-2 mRNA abundance in amnion explants was determined. Prorenin and (P)RR mRNA were highest in decidua and placenta, respectively. Decidual prorenin, (P)RR and placental (P)RR mRNA abundance decreased with labour. (P)RR protein was present in all gestational tissues. After labour, decidual prorenin was positively correlated with amnion PGHS-2 mRNA and rh-prorenin significantly increased PGHS-2 mRNA abundance in amnion explants. We conclude that the decidua is the principal source of prorenin and is downregulated with labour. All gestational tissues are targets for prorenin. Decidual prorenin may be involved in the labour-associated increase in amnion PGHS-2 abundance via the (P)RR.

Help-seeking by older husbands caring for wives with dementia.

AIM: This paper reports a study to gain understanding of the help-seeking process of older husbands caring for wives with dementia. BACKGROUND: Men comprise 41% of spousal caregivers. However, few reports describe older husbands' caregiving experiences and none specifically explore help-seeking in men caring for wives with dementia. METHOD: A grounded theory design was used to discover a theory of help-seeking by older caregiver husbands. Audiotaped interviews were conducted during 2004 and 2005 with nine husband participants. The interviews were analysed by a research group to discover the core category and the relationships of related categories to develop a theory of help-seeking that was grounded in the data. Margaret Newman's theory of Health as Expanding Conscious provided a theoretical perspective for interpretation of the findings. FINDINGS: The core category, 'Doing the best I can', was preceded by the antecedent of 'changing patterns'. Husbands made choices to use action/interaction strategies of 'Relinquishing', 'Reaching out' and 'Shouldering' which were influenced by a variety of internal, relational, situational, and experiential facilitating or hindering intervening conditions. The consequence of help-seeking process was 'Continuing on', which had categories of: 'Keeping at home', 'Staying together', and 'Taking care of myself'. CONCLUSION: Help-seeking by older husband caregivers is complex and gender-specific. Interventions to assist these caregivers must also be gender-specific and complement already existing help-seeking patterns. Focusing on helping caregivers to discover their patterns of relating and help-seeking empowers them to find new ways of interacting and to discover possibilities for action.

Optimization of a solid phase extraction procedure for prostaglandin E2, F2 alpha and their tissue metabolites.

The primary prostaglandins PGE(2) and PGF(2 alpha) are metabolized in tissues by a series of enzymatic and non-enzymatic reactions. To measure metabolic rates and individual reaction rates it is necessary to extract the parent prostaglandins and metabolites before the separation and quantification of each compound is achieved. Here we have established and optimized a solid phase extraction (SPE) procedure to recover PGE(2), PGF(2 alpha) and their six enzymatic and non-enzymatic tissue metabolites from aqueous solutions including urine, plasma and tissue homogenate. We have used octadecyl-bonded silica gel as the stationary phase and methanol-water mixtures as binary mobile phases. The volumes and concentrations of the washing and elution solutions were optimized individually for each PG. Recoveries of all PG standards were quantitative except for PGEM, which was recovered at 80% efficiency. Biological matrix components interfered with the extraction in a PG- and matrix-specific fashion. Inclusion of 1% formic acid in the loading mixture raised recoveries from urine, plasma and tissue homogenate to >or=90%. This SPE method is the first that has been optimized by systematic elution studies for PGE(2), PGF(2 alpha) and the complement of their tissue metabolites. The procedure is simple, robust and can serve as an effective pre-purification step before downstream separation and quantification of each tissue metabolite of PGE(2) and PGF(2 alpha) from complex biological matrices.

Mechanisms regulating prostaglandin H2 synthase-2 mRNA level in the amnion and chorion during pregnancy.

Increasing prostaglandin H(2) synthase (PGHS)-2 expression in the fetal membranes is implicated in the production of prostaglandins (PGs) that stimulate labour. We have determined the activity of the PGHS-2 gene in the amnion and chorion throughout gestation and defined the contribution of transcriptional and post-transcriptional mechanisms to the increase of PGHS-2 mRNA levels. We also measured PGHS-1 mRNA abundance to assess the participation of the two isoenzymes in fetal membrane PG-production during pregnancy. Amnion and chorion were collected from non-labouring women at 10-19 weeks (early), at 28-36 weeks (preterm) and at term (37-41 weeks). We determined PGHS-1 and -2 mRNA abundance and assessed PGHS-2 gene activity by measuring PGHS-2 heterogeneous nuclear RNA levels using real-time RT-PCR. PGHS-2 gene activity and mRNA levels were up-regulated in both tissues with advancing gestation. Path analysis demonstrated that the PGHS-2 mRNA up-regulation involved both transcriptional and post-transcriptional components. PGHS-2 mRNA abundance increased 9-11 fold between the early (10-19 weeks) and preterm (28-36 weeks) groups and remained high at term. The underlying mechanism was predominantly transcriptional in the amnion and post-transcriptional in the chorion. PGHS-1 mRNA expression precipitously decreased between early gestation and term. Thus, PGHS-2 mRNA abundance is up-regulated well in advance of term and is not a trigger for labour. There is a switch in PGHS mRNA expression during pregnancy with PGHS-1 dominating in the early period and PGHS-2 dominating at term.

Prostaglandin H2 synthase-1 and -2 expression in guinea pig gestational tissues during late pregnancy and parturition.

Increased intrauterine prostaglandin (PG) production is crucial for the initiation of parturition. To investigate the mechanisms controlling intrauterine PG synthesis, we examined the expression of the key PG biosynthetic isoenzymes, PG-H2 synthase (PTGS)-1 and -2, in the amnion, visceral yolk sac (VYS), placenta and myo-endometrium of pregnant guinea pigs. This animal model was chosen because the hormonal milieu of pregnancy and the role of PGs in the hormonal control of parturition are similar to those in the human. PTGS1 mRNA abundance, measured by real-time RT-PCR, increased in the amnion and the placenta during the last third of gestation. During labour, PTGS1 mRNA levels decreased precipitously in all four tissues. PTGS1 protein abundance, assessed by immunoblotting, increased to high levels in the amnion and the placenta by the end of pregnancy and remained high during labour. PTGS2 mRNA expression was higher in the placenta than in the other tissues, but did not change before and during labour. PTGS2 protein expression decreased in the placenta and remained low in the other tissues during labour. Immunohistochemistry showed pervasive PTGS1 protein expression in the amnion and strong expression in the parietal yolk sac membrane (PYS) covering the placenta. PTGS2 was expressed in the PYS and the endometrium. The PTGS inhibitor piroxicam, administered in doses that inhibited PTGS1 but not PTGS2, significantly prolonged gestation. These data suggest that PGs generated by intrauterine PTGS1 are involved in the timing of birth in guinea pigs. The induction of PTGS1 in the amnion and the PYS is a critical event leading to labour in guinea pigs and models analogous changes in the human gestational tissues before labour.

Regulation of 15-hydroxyprostaglandin dehydrogenase (PGDH) gene activity, messenger ribonucleic acid processing, and protein abundance in the human chorion in late gestation and labor.

The prostaglandin (PG)-inactivating enzyme 15-hydroxyprostaglandin dehydrogenase (PGDH) is highly expressed in the chorion leave. To assess the involvement of PGDH in the regulation of intrauterine PG levels, we have determined the mechanisms that control chorionic PGDH expression in women at term and preterm labor. PGDH gene activity decreased at term and during normal labor. PGDH mRNA abundance also decreased at term due to changing splice variant distribution. Gene activity predicted PGDH mRNA abundance preterm and after normal labor, but not at term before labor. PGDH mRNA decayed rapidly in cultured tissues and was stabilized by transcriptional arrest. PGDH protein levels varied without being significantly different between the patient groups. PGDH mRNA levels predicted PGDH protein levels at term, but not preterm and after labor. PGDH gene activity, mRNA variant, and immunoreactive protein levels were not different between the preterm labor and preterm not in labor groups. Thus, PGDH mRNA is transiently down-regulated before term labor by a posttranscriptional mechanism(s). Protein turnover controls PGDH protein abundance at preterm and after normal labor. At term, PGDH protein levels become dependent on the rapidly turning over PGDH mRNA. This may allow rapid changes in PGDH protein abundance and uterotonic PG concentrations promoting labor.

The control of prostaglandin endoperoxide H-Synthase-2 expression in the human chorion laeve at term.

OBJECTIVE: Prostaglandin endoperoxide H synthase-2 (PGHS-2), the key enzyme of prostaglandin biosynthesis in gestational tissues, is expressed in the chorion laeve at term. We have determined the mechanisms that control the level of PGHS-2 mRNA in the chorion membrane in order to assess the significance of chorion-derived prostaglandins in term labor. METHODS: Chorion membranes were collected after elective cesarean delivery (CD, n = 21) and after spontaneous labor (SL, n = 20) at term. The PGHS-2 gene transcription rate was measured by transcriptional run-on, and PGHS-2 mRNA and heterogeneous RNA (hnRNA) abundance was determined by quantitative real-time reverse transcriptase polymerase chain reaction. PGHS-2 mRNA stability, PGHS-2 hnRNA processing rate, and the short-term dynamics of the two RNA species were characterized in 0-24-hour-long tissue incubations. RESULTS: The transcriptional activity of the PGHS-2 gene predicted (P <.02) the abundance of PGHS-2 mRNA and hnRNA in individual tissues. PGHS-2 gene activity and hnRNA processing rate were not different in the CD and SL groups. PGHS-2 mRNA was constitutively stable before and after labor, and its abundance spontaneously increased sixfold in tissues incubated for 24 hours. At the same time, PGHS-2 gene activity decreased by 80% within 2 hours and rebounded to 60% of its initial level by 24 hours. CONCLUSIONS: PGHS-2 mRNA is highly stable, and its abundance is transcriptionally controlled in the chorion laeve at term. Labor is not associated with changing PGHS-2 gene activity. Endogenous factors drive PGHS-2 gene transcription in the chorion, and the stable PGHS-2 mRNA accumulates in the tissue at term. This accumulation has little or no impact on the timing of labor.

The in vivo control of prostaglandin H synthase-2 messenger ribonucleic acid expression in the human amnion at parturition.

Prostaglandin H synthase-2 (PGHS-2) activity and mRNA rise in the human amnion at late gestation, contributing to the increase in intrauterine PG production crucial for labor and delivery. In the present investigation we have determined the mechanism that controls amniotic PGHS-2 mRNA levels in vivo at term parturition. Amnion membranes were collected after elective cesarean section (n = 20), and after spontaneous labor (n = 20). PGHS-2 relative gene transcription rates were determined by transcriptional run-on, and PGHS-2 mRNA and heterogeneous nuclear RNA (hnRNA) relative abundance were measured by quantitative real-time RT-PCR. The PGHS-2 mRNA degradation rate was determined by incubating amnion in the presence of the transcription inhibitor 5,6-dichlorobenzimidazole riboside. The dynamics of PGHS-2 hnRNA and mRNA abundance were characterized in 0- to 24-h tissue incubations. The PGHS-2 relative gene transcription rate was a significant (P < 0.05) predictor of PGHS-2 hnRNA and mRNA abundance, and PGHS-2 hnRNA was also a predictor (P < 0.01) of PGHS-2 mRNA levels both before and after labor. Interestingly, even though PGHS-2 gene activity remained unchanged, PGHS-2 mRNA abundance increased with labor and displayed constitutive stability before and after labor. PGHS-2 mRNA levels spontaneously increased by 400% (P < 0.01) upon incubation for 24 h, whereas the transcription rate dropped by 95% during the first 2 h, then rebounded significantly between 6-24 h. Thus, PGHS-2 mRNA abundance is transcriptionally controlled in term amnion. Labor does not increase PGHS-2 gene activity or mRNA stability. The PGHS-2 gene is probably induced before labor by a factor(s) originating in the amnion membrane, and the resulting stable mRNA accumulates progressively in the tissue throughout labor and delivery.