Risk factors and outcomes of uterine rupture in Singapore: Emerging trends.

INTRODUCTION: Uterine rupture is uncommon but has catastrophic implications on the pregnancy. A scarred uterus and abnormal placentation are known contributory factors. The aim of our study was to review the contributing factors, clinical presentation, complications and management of uterine rupture in our population in light of the changing nature of modern obstetric practices. METHODS: A retrospective observational study was conducted at KK Women's and Children's Hospital by studying proven cases of uterine rupture in the period between January 2003 and December 2014. These cases were analysed according to their past history, clinical presentation, complications, management and outcome. RESULTS: A total of 48 cases of proven uterine rupture were identified. The incidence of uterine rupture was 1 in 3,062 deliveries. The ratio of scarred uterus rupture to unscarred uterus rupture was approximately 3:1. The most common factor was previous lower segment caesarean section for the scarred group, followed by a history of laparoscopic myomectomy. Abdominal pain was the common clinical presentation in the antenatal period, while abnormal cardiotocography findings were the most common presentation in intrapartum rupture. CONCLUSION: There is a notable shift in the trend of uterine rupture cases given the increasing use of laparoscopic myomectomy and elective caesarean sections. While ruptures from these cases were few, their presentation in the antenatal period calls for diligent monitoring with informed patient involvement in their pregnancy care.

MST3 Involvement in Na+ and K+ Homeostasis with Increasing Dietary Potassium Intake.

K+ loading inhibits NKCC2 (Na-K-Cl cotransporter) and NCC (Na-Cl cotransporter) in the early distal tubules, resulting in Na+ delivery to the late distal convoluted tubules (DCTs). In the DCTs, Na+ entry through ENaC (epithelial Na channel) drives K+ secretion through ROMK (renal outer medullary potassium channel). WNK4 (with-no-lysine 4) regulates the NCC/NKCC2 through SAPK (Ste20-related proline-alanine-rich kinase)/OSR1 (oxidative stress responsive). K+ loading increases intracellular Cl-, which binds to the WNK4, thereby inhibiting autophosphorylation and downstream signals. Acute K+ loading-deactivated NCC was not observed in Cl--insensitive WNK4 mice, indicating that WNK4 was involved in K+ loading-inhibited NCC activity. However, chronic K+ loading deactivated NCC in Cl--insensitive WNK4 mice, indicating that other mechanisms may be involved. We previously reported that mammalian Ste20-like protein kinase 3 (MST3/STK24) was expressed mainly in the medullary TAL (thick ascending tubule) and at lower levels in the DCTs. MST3 -/- mice exhibited higher ENaC activity, causing hypernatremia and hypertension. To investigate MST3 function in maintaining Na+/K+ homeostasis in kidneys, mice were fed diets containing various concentrations of Na+ and K+. The 2% KCl diets induced less MST3 expression in MST3 -/- mice than that in wild-type (WT) mice. The MST3 -/- mice had higher WNK4, NKCC2-S130 phosphorylation, and ENaC expression, resulting in lower urinary Na+ and K+ excretion than those of WT mice. Lower urinary Na+ excretion was associated with elevated plasma [Na+] and hypertension. These results suggest that MST3 maintains Na+/K+ homeostasis in response to K+ loading by regulation of WNK4 expression and NKCC2 and ENaC activity.

Risk factors and outcomes of uterine rupture in Singapore: Emerging trends

INTRODUCTION@#Uterine rupture is uncommon but has catastrophic implications on the pregnancy. A scarred uterus and abnormal placentation are known contributory factors. The aim of our study was to review the contributing factors, clinical presentation, complications and management of uterine rupture in our population in light of the changing nature of modern obstetric practices.@*METHODS@#A retrospective observational study was conducted at KK Women's and Children's Hospital by studying proven cases of uterine rupture in the period between January 2003 and December 2014. These cases were analysed according to their past history, clinical presentation, complications, management and outcome.@*RESULTS@#A total of 48 cases of proven uterine rupture were identified. The incidence of uterine rupture was 1 in 3,062 deliveries. The ratio of scarred uterus rupture to unscarred uterus rupture was approximately 3:1. The most common factor was previous lower segment caesarean section for the scarred group, followed by a history of laparoscopic myomectomy. Abdominal pain was the common clinical presentation in the antenatal period, while abnormal cardiotocography findings were the most common presentation in intrapartum rupture.@*CONCLUSION@#There is a notable shift in the trend of uterine rupture cases given the increasing use of laparoscopic myomectomy and elective caesarean sections. While ruptures from these cases were few, their presentation in the antenatal period calls for diligent monitoring with informed patient involvement in their pregnancy care.

Removal and fate of polycyclic aromatic hydrocarbon pollutants in an urban stormwater bioretention facility.

This research investigated the removal and fate of 16 USEPA priority pollutant polycyclic aromatic hydrocarbons (PAHs) from urban stormwater runoff through a bioretention cell. Bioretention is an infiltration/filtration practice containing a mixed layer of about 90 cm of soil, sand, and organic matter, planted with appropriate vegetation. Field water quality monitoring and bioretention media core analyses were performed. The results indicate that bioretention is a promising management practice to control runoff PAH pollutants. The PAH event mean concentration (EMC) reduction ranged from 31 to 99%, with a mean discharge EMC of 0.22 microg/L. The mass load decreased from a mean value of 0.0180 kg/ha yr to 0.0025 kg/ha yr, suggesting an average PAH mass load reduction of 87% to the discharging watershed. The most dominant PAH species monitored were fluoranthene and pyrene. Influent PAHs indicated strong affiliation with runoff total suspended solids (TSS). As such, PAH removal positively correlated with TSS removal. Low rainfall depth was associated with high influent PAH concentration and resulted in favorable PAH removal. Source investigation suggested that the PAHs measured in the monitored cell were from pyrogenic sources, likely resulting from vehicle combustion processes. Sealers used in parking lots and driveway coatings were also a possible source of PAHs. Media core analyses indicated that the intercepted PAH compounds transported only a few centimeters vertically in the soil media near the runoff entrance location, suggesting that a shallow cell design may be adequate for systems focusing on PAH removal.

Heavy metal capture and accumulation in bioretention media.

Heavy metal capture and accumulation in bioretention media were investigated through the use of a one-dimensional filtration equation for particulate metals, advection/dispersion/adsorption transport equations for dissolved metals, and sequential extractions. Predicted spatial profiles and partitioning patterns of captured metals were compared to data derived from a bioretention cell in the District of Columbia. Zinc, lead, and copper profiles showed a high surface accumulation, significantly decreasing with the media depth. Surface street particle-enriched areas had the highest heavy metal levels, demonstrating a close relationship between capture of metals and runoff particles. Sequential extractions suggested that most captured metals were of anthropogenic origin. Soluble-exchangeable bound metals from the sequential extraction correlated well with predicted aqueous dissolved metals; the more strongly associated metal fractions correlated with modeled runoff and media particulate metals. A simple risk evaluation indicated thatlead isthe limiting metal in bioretention accumulation. On the basis of information collected in this study, a shallow bioretention cell design is suggested for systems with a focus on metal capture.

Measuring a toddler's mouthful: toxicologic considerations.

The volume of a toddler's mouthful needs to be defined to estimate poisoning risk. We calculated a toddler's mouthful in 66 healthy children (1.5-4.5 years old) by measuring apple juice remaining in a cup after sipping. Mean volume was 9.3 mL (range, 3.5-29; 95% confidence interval, 8-11), twofold larger than commonly quoted values.