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1.
Aust N Z J Obstet Gynaecol ; 63(3): 321-327, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36184072

RESUMEN

BACKGROUND: Antenatal detection of fetal growth restriction allows the opportunity to increase surveillance and initiate intervention to prevent adverse outcomes. Detection of small for gestational age (SGA) fetuses with risk factor screening and selective ultrasonography is the standard of care in Australia, but evidence regarding performance is lacking. AIMS: To evaluate the diagnostic performance of a risk factor-based screening approach in detection of SGA neonates. MATERIALS AND METHODS: Retrospective cohort study conducted in a metropolitan maternity service, including all consecutive singleton deliveries over 20 weeks gestation from July 2016 to December 2017, and excluding terminations of pregnancy. An SGA neonate was defined by birthweight below the tenth percentile according to Australian reference ranges. Antenatally detected SGA cases were defined by estimated fetal weight or abdominal circumference below the tenth percentile for gestational age, or abnormal symphysio-fundal height. The diagnostic accuracy of the screening protocol was calculated using detection rates and false-positive rates. RESULTS: There were 13 384 singleton pregnancies included. There were 1330 infants (10.0%) who were SGA at birth. Antenatal detection rate of SGA neonates was 39.6% (95% confidence interval (CI) 37.0-42.3%), with a false-positive rate of 10.2% (95% CI 9.6-10.7%). There were 10 266 pregnancies (77.0%) which had at least one risk factor for an SGA infant. Of these, 6650 (64.8%) underwent at least one fetal growth ultrasound after 24 weeks gestation. CONCLUSIONS: Antenatal recognition of poor fetal growth is suboptimal using our current screening protocol. Three-quarters of pregnancies demonstrated risk factors for delivering an SGA infant, but growth ultrasonography may be underutilised.


Asunto(s)
Retardo del Crecimiento Fetal , Recién Nacido , Embarazo , Femenino , Humanos , Retardo del Crecimiento Fetal/diagnóstico por imagen , Estudios de Cohortes , Edad Gestacional , Estudios Retrospectivos , Tercer Trimestre del Embarazo , Australia , Factores de Riesgo
3.
Nat Rev Cardiol ; 19(8): 522-542, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35102320

RESUMEN

Atherosclerosis is a chronic inflammatory disease of the arterial wall, characterized by the formation of plaques containing lipid, connective tissue and immune cells in the intima of large and medium-sized arteries. Over the past three decades, a substantial reduction in cardiovascular mortality has been achieved largely through LDL-cholesterol-lowering regimes and therapies targeting other traditional risk factors for cardiovascular disease, such as hypertension, smoking, diabetes mellitus and obesity. However, the overall benefits of targeting these risk factors have stagnated, and a huge global burden of cardiovascular disease remains. The indispensable role of immunological components in the establishment and chronicity of atherosclerosis has come to the forefront as a clinical target, with proof-of-principle studies demonstrating the benefit and challenges of targeting inflammation and the immune system in cardiovascular disease. In this Review, we provide an overview of the role of the immune system in atherosclerosis by discussing findings from preclinical research and clinical trials. We also identify important challenges that need to be addressed to advance the field and for successful clinical translation, including patient selection, identification of responders and non-responders to immunotherapies, implementation of patient immunophenotyping and potential surrogate end points for vascular inflammation. Finally, we provide strategic guidance for the translation of novel targets of immunotherapy into improvements in patient outcomes.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Placa Aterosclerótica , LDL-Colesterol , Humanos , Inflamación
4.
ACS Synth Biol ; 10(12): 3264-3277, 2021 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-34851109

RESUMEN

Agricultural productivity relies on synthetic nitrogen fertilizers, yet half of that reactive nitrogen is lost to the environment. There is an urgent need for alternative nitrogen solutions to reduce the water pollution, ozone depletion, atmospheric particulate formation, and global greenhouse gas emissions associated with synthetic nitrogen fertilizer use. One such solution is biological nitrogen fixation (BNF), a component of the complex natural nitrogen cycle. BNF application to commercial agriculture is currently limited by fertilizer use and plant type. This paper describes the identification, development, and deployment of the first microbial product optimized using synthetic biology tools to enable BNF for corn (Zea mays) in fertilized fields, demonstrating the successful, safe commercialization of root-associated diazotrophs and realizing the potential of BNF to replace and reduce synthetic nitrogen fertilizer use in production agriculture. Derived from a wild nitrogen-fixing microbe isolated from agricultural soils, Klebsiella variicola 137-1036 ("Kv137-1036") retains the capacity of the parent strain to colonize corn roots while increasing nitrogen fixation activity 122-fold in nitrogen-rich environments. This technical milestone was then commercialized in less than half of the time of a traditional biological product, with robust biosafety evaluations and product formulations contributing to consumer confidence and ease of use. Tested in multi-year, multi-site field trial experiments throughout the U.S. Corn Belt, fields grown with Kv137-1036 exhibited both higher yields (0.35 ± 0.092 t/ha ± SE or 5.2 ± 1.4 bushels/acre ± SE) and reduced within-field yield variance by 25% in 2018 and 8% in 2019 compared to fields fertilized with synthetic nitrogen fertilizers alone. These results demonstrate the capacity of a broad-acre BNF product to fix nitrogen for corn in field conditions with reliable agronomic benefits.


Asunto(s)
Grano Comestible , Fijación del Nitrógeno , Agricultura , Productos Agrícolas , Grano Comestible/química , Fertilizantes/análisis , Nitrógeno
5.
PLoS One ; 16(10): e0258634, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34669758

RESUMEN

OBJECTIVE: To investigate whether fetuses with accelerated third trimester growth velocity are at increased risk of shoulder dystocia, even when they are not large-for-gestational-age (LGA; estimated fetal weight (EFW) >95th centile). METHODS: Fetal growth velocity and birth outcome data were prospectively collected from 347 nulliparous women. Each had blinded ultrasound biometry performed at 28 and 36 weeks' gestation. Change in EFW and abdominal circumference (AC) centiles between 28-36 weeks were calculated, standardised over exactly eight weeks. We examined the odds of shoulder dystocia with increasing EFW and AC growth velocities among women with 36-week EFW ≤95th centile (non-LGA), who went on to have a vaginal birth. We then examined the relative risk (RR) of shoulder dystocia in cases of accelerated EFW and AC growth velocities (>30 centiles gained). Finally, we compared the predictive performances of accelerated fetal growth velocities to 36-week EFW >95th centile for shoulder dystocia among the cohort planned for vaginal birth. RESULTS: Of the 226 participants who had EFW ≤95th centile at 36-week ultrasound and birthed vaginally, six (2.7%) had shoulder dystocia. For each one centile increase in EFW between 28-36 weeks, the odds of shoulder dystocia increased by 8% (odds ratio (OR [95% Confidence Interval (CI)]) = 1.08 [1.04-1.12], p<0.001). For each one centile increase in AC between 28-36 weeks, the odds of shoulder dystocia increased by 9% (OR[95%CI] = 1.09 [1.05-1.12], p<0.001). When compared to the rest of the cohort with normal growth velocity, accelerated EFW and AC velocities were associated with increased relative risks of shoulder dystocia (RR[95%CI] = 7.3 [1.9-20.6], p = 0.03 and 4.8 [1.7-9.4], p = 0.02 respectively). Accelerated EFW or AC velocities predicted shoulder dystocia with higher sensitivity and positive predictive value than 36-week EFW >95th centile. CONCLUSIONS: Accelerated fetal growth velocities between 28-36 weeks' gestation are associated with increased risk of shoulder dystocia, and may predict shoulder dystocia risk better than the commonly used threshold of 36-week EFW >95th centile.


Asunto(s)
Macrosomía Fetal/diagnóstico por imagen , Distocia de Hombros/epidemiología , Adulto , Biometría , Femenino , Desarrollo Fetal , Macrosomía Fetal/complicaciones , Peso Fetal , Edad Gestacional , Humanos , Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Distocia de Hombros/etiología , Ultrasonografía Prenatal , Circunferencia de la Cintura
6.
BMJ Case Rep ; 14(4)2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33858905

RESUMEN

We present the case of a baby boy, with antenatal finding of bilateral enlarged echogenic lungs, who developed severe postnatal respiratory failure. Two important differential diagnoses, which have an impact on antenatal and postnatal management, are discussed. Fetal ultrasound, MRI and postmortem MRI images are presented and findings correlated with the autopsy findings.


Asunto(s)
Malformación Adenomatoide Quística Congénita del Pulmón , Insuficiencia Respiratoria , Femenino , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Pulmón/diagnóstico por imagen , Masculino , Embarazo , Ultrasonografía Prenatal
7.
Int J Eat Disord ; 54(4): 615-620, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33462885

RESUMEN

OBJECTIVE: While there is evidence to support the use of group dialectical behavior therapy (DBT) in the treatment of binge-eating disorder (BED), treatment is relatively long compared with other evidence-based treatments. This study explored the effectiveness of brief DBT groups for BED, delivered in a routine community setting. METHOD: Eighty-four adults with BED entered 10-week DBT group treatment in a community eating disorders service. In total, 12 groups were conducted. Patients completed measures of eating disorder pathology, anxiety, depression, and emotional eating at the start and end of treatment, and at 1-month follow-up. Frequency of weekly binges was recorded. RESULTS: Outcomes were similar to those of longer versions of DBT, with an attrition rate of 26%, and significant reductions in eating disorder psychopathology and emotional eating by the end of treatment and at follow-up. Over 50% of patients were abstinent from binge eating by Session 4. DISCUSSION: Group DBT delivered in a 10-session format is clinically equivalent to longer versions of the same treatment. Future research is required to explore patterns of change and to demonstrate replicability under controlled conditions, but these findings are promising for the efficient delivery of effective treatment and reducing waiting times.


Asunto(s)
Trastorno por Atracón , Bulimia , Terapia Conductual Dialéctica , Adulto , Terapia Conductista , Trastorno por Atracón/terapia , Emociones , Humanos , Resultado del Tratamiento
8.
BMC Med ; 18(1): 395, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33357243

RESUMEN

BACKGROUND: Fetal growth restriction (FGR) due to placental insufficiency is a major risk factor for stillbirth. While small-for-gestational-age (SGA; weight < 10th centile) is a commonly used proxy for FGR, detection of FGR among appropriate-for-gestational-age (AGA; weight ≥ 10th centile) fetuses remains an unmet need in clinical care. We aimed to determine whether reduced antenatal growth velocity from the time of routine mid-trimester ultrasound is associated with antenatal, intrapartum and postnatal indicators of placental insufficiency among term AGA infants. METHODS: Three hundred and five women had biometry measurements recorded from their routine mid-trimester (20-week) ultrasound, at 28 and 36 weeks' gestation, and delivered an AGA infant. Mid-trimester, 28- and 36-week estimated fetal weight (EFW) and abdominal circumference (AC) centiles were calculated. The EFW and AC growth velocities between 20 and 28 weeks, and 20-36 weeks, were examined as predictors of four clinical indicators of placental insufficiency: (i) low 36-week cerebroplacental ratio (CPR; CPR < 5th centile reflects cerebral redistribution-a fetal adaptation to hypoxia), (ii) neonatal acidosis (umbilical artery pH < 7.15) after the hypoxic challenge of labour, (iii) low neonatal body fat percentage (BF%) reflecting reduced nutritional reserve and (iv) placental weight < 10th centile. RESULTS: Declining 20-36-week fetal growth velocity was associated with all indicators of placental insufficiency. Each one centile reduction in EFW between 20 and 36 weeks increased the odds of cerebral redistribution by 2.5% (odds ratio (OR) = 1.025, P = 0.001), the odds of neonatal acidosis by 2.7% (OR = 1.027, P = 0.002) and the odds of a < 10th centile placenta by 3.0% (OR = 1.030, P < 0.0001). Each one centile reduction in AC between 20 and 36 weeks increased the odds of neonatal acidosis by 3.1% (OR = 1.031, P = 0.0005), the odds of low neonatal BF% by 2.8% (OR = 1.028, P = 0.04) and the odds of placenta < 10th centile by 2.1% (OR = 1.021, P = 0.0004). Falls in EFW or AC of > 30 centiles between 20 and 36 weeks were associated with two-threefold increased relative risks of these indicators of placental insufficiency, while low 20-28-week growth velocities were not. CONCLUSIONS: Reduced growth velocity between 20 and 36 weeks among AGA fetuses is associated with antenatal, intrapartum and postnatal indicators of placental insufficiency. These fetuses potentially represent an important, under-recognised cohort at increased risk of stillbirth. Encouragingly, this novel fetal assessment would require only one additional ultrasound to current routine care, and adds to the potential benefits of routine 36-week ultrasound.


Asunto(s)
Adaptación Fisiológica/fisiología , Desarrollo Fetal/fisiología , Retardo del Crecimiento Fetal/etiología , Peso Corporal Ideal , Insuficiencia Placentaria , Segundo Trimestre del Embarazo/fisiología , Adulto , Peso al Nacer , Estudios de Cohortes , Femenino , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/epidemiología , Peso Fetal/fisiología , Edad Gestacional , Humanos , Recién Nacido , Masculino , Insuficiencia Placentaria/diagnóstico , Insuficiencia Placentaria/epidemiología , Insuficiencia Placentaria/fisiopatología , Embarazo , Factores de Riesgo , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagen , Adulto Joven
9.
PLoS One ; 15(9): e0238700, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32898169

RESUMEN

BACKGROUND: Postnatally, small-for-gestational-age (SGA; birthweight <10th centile) infants who are growth restricted due to uteroplacental insufficiency (UPI) demonstrate 'catch-up growth' to meet their genetically-predetermined size. Infants who demonstrate slowing growth during pregnancy are those that cross estimated fetal weight centiles at serial ultrasound examinations. These infants that slow in growth but are born appropriate-for-gestational-age (AGA; ≥10th centile), exhibit antenatal, intrapartum and postnatal indicators of UPI. Here, we examine if and when these infants (labelled as AGA-FGR) also demonstrate catch-up growth like SGA infants, when compared with AGA infants with normal antenatal growth velocity (AGA-NG). METHODS: We followed-up the infants of women who had previously undergone ultrasound assessment of fetal size at 28- and 36-weeks' gestation, enabling calculation of antenatal growth velocity. To assess postnatal growth, we asked parents to send their infant's growth measurements, up to two years post-birth, which are routinely collected through the state-wide Maternal-Child Health service. Infants with medical conditions affecting postnatal growth were excluded from the analysis. From the measurements obtained we calculated age-adjusted z-scores for postnatal weight, length and body mass index (BMI; weight(kg)/height(m2)) at birth and 4, 8, 12, 18 and 24 months. We used linear spline regression modelling to predict mean weight, length and BMI z-scores at intervals post birth. Predicted mean age-adjusted z-scores were then compared between three groups; SGA, AGA with low antenatal growth (AGA-FGR; loss of >20 customised estimated fetal weight centiles), and AGA-NG to determine if catch-up growth occurred. In addition, we compared the rates of catch-up growth (defined as an increase in weight age-adjusted z-score of ≥0.67 over 1 year) between the groups with Fisher's exact tests. RESULTS: Of 158 (46%) infant growth records received, 146 were AGA, with low antenatal growth velocity occurring in 34/146 (23.2%). Rates of gestational diabetes and SGA birthweight were higher in those lost to follow-up. Compared to AGA-NG infants, AGA-FGR infants had significantly lower predicted mean weight (p<0.001), length (p = 0.04) and BMI (p = 0.001) z-scores at birth. These significant differences were no longer evident at 4 months, suggesting that catch-up growth had occurred. As expected, the catch-up growth that occurred among the AGA-FGR was not as great in magnitude as that demonstrated by the SGA. When assessed categorically, there was no significant difference between the rate of catch-up growth among the AGA-FGR and the SGA. Catch-up growth was significantly more frequent among both the AGA-FGR and the SGA groups compared to the AGA-NG. CONCLUSIONS: AGA infants that have exhibited reduced antenatal fetal growth velocity also exhibit significant catch-up growth in the first 12 months of life. This finding represents further evidence that AGA fetuses that slow in growth during pregnancy do so due to UPI.


Asunto(s)
Desarrollo Infantil , Edad Gestacional , Adulto , Peso al Nacer , Estatura , Índice de Masa Corporal , Retardo del Crecimiento Fetal , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional/crecimiento & desarrollo , Riesgo
10.
EMBO J ; 39(11): e102539, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32311122

RESUMEN

Multiple mitochondrial quality control pathways exist to maintain the health of mitochondria and ensure cell homeostasis. Here, we investigate the role of the endosomal adaptor Tollip during the mitochondrial stress response and identify its interaction and colocalisation with the Parkinson's disease-associated E3 ubiquitin ligase Parkin. The interaction between Tollip and Parkin is dependent on the ubiquitin-binding CUE domain of Tollip, but independent of Tom1 and mitophagy. Interestingly, this interaction is independent of Parkin mitochondrial recruitment and ligase activity but requires an intact ubiquitin-like (UBL) domain. Importantly, Tollip regulates Parkin-dependent endosomal trafficking of a discrete subset of mitochondrial-derived vesicles (MDVs) to facilitate delivery to lysosomes. Retromer function and an interaction with Tom1 allow Tollip to facilitate late endosome/lysosome trafficking in response to mitochondrial stress. We find that upregulation of TOM20-positive MDVs upon mitochondrial stress requires Tollip interaction with ubiquitin, endosomal membranes and Tom1 to ensure their trafficking to the lysosomes. Thus, we conclude that Tollip, via an association with Parkin, is an essential coordinator to sort damaged mitochondrial-derived cargo to the lysosomes.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mitocondrias/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Endosomas/genética , Endosomas/metabolismo , Células HEK293 , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Lisosomas/genética , Lisosomas/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Mitocondrias/genética , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Transporte de Proteínas , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Ubiquitina-Proteína Ligasas/genética
11.
Aust N Z J Obstet Gynaecol ; 60(5): 766-772, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32291746

RESUMEN

BACKGROUND: Accurate estimation of fetal weight is essential in guiding management of fetuses with abdominal wall defects (AWDs), as growth restriction is an important predictor of perinatal morbidity and mortality. Several sonographic formulae are available involving multiple biometric parameters, but abdominal circumference measurements may underestimate weight in fetuses with AWDs. No formula has yet shown superior accuracy. AIMS: The objectives of this study were to evaluate, in fetuses with gastroschisis and omphalocoele, the accuracy of a sonographic estimated fetal weight (EFW) formula proposed by Siemer and colleagues, specifically for use in fetuses with AWDs compared to the commonly used Hadlock IV formula in estimating fetal weight, and detecting small for gestational age (SGA) fetuses. MATERIALS AND METHODS: A retrospective cohort of 113 fetuses with AWDs was identified from an Australian teaching hospital over 13 years. Pregnancy data and sonographic fetal biometry parameters were obtained. The accuracy of each formula in predicting birthweight was compared using Bland-Altman limits of agreement, and the intraclass correlation coefficient between EFW and actual birthweight. Performance of each formula in detecting SGA fetuses was determined. RESULTS: The Siemer and Hadlock formulae have similar accuracies for predicting birthweight in fetuses with AWDs. The Hadlock formula has a higher detection rate for SGA < 10th centile and < 3rd centile compared to the Seimer formula (84% vs 68% and 83% vs 67% respectively), albeit with a higher false-positive rate. CONCLUSION: There is no clear clinical advantage in using the Siemer formula, which is specifically designed for fetuses with AWDs, over the Hadlock formula to estimate weight in fetuses with AWDs.


Asunto(s)
Pared Abdominal , Pared Abdominal/diagnóstico por imagen , Australia , Peso al Nacer , Femenino , Peso Fetal , Feto , Edad Gestacional , Humanos , Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal
12.
J Matern Fetal Neonatal Med ; 32(5): 760-767, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29020812

RESUMEN

INTRODUCTION: The fetal left modified Myocardial Performance Index (Mod-myocardial performance index (MPI)) is a measure of systolic versus diastolic time intervals obtained from a single cardiac cycle with ultrasound. It is a measure of global ventricular function and has been investigated for potential utility in fetal conditions associated with cardiac dysfunction. OBJECTIVES: The objective of this study is to compare values from a precisely replicated fetal left Mod-MPI technique to published reference ranges. METHODS: Three hundred and sixty-five nulliparae prospectively underwent fetal left Mod-MPI measurement at 27+0-29+0 and 35+0-37+0 weeks' gestation. Measurements from pregnancies complicated by gestational diabetes mellitus, preeclampsia, or a small-for-gestational-age (<10th centile) infant were excluded. Mod-MPI values were compared with three published references created using similar measurement techniques. RESULTS: Compared with one selected reference, at 29+0 and 35+0-37+0 weeks' gestation, 90-100% of our values fell within the 5th-95th percentile range as expected. Thus, this reference range was validated for our population in late pregnancy. However, the expected level of concordance was not seen at 27+0-28+6 weeks'. The other two references to which we compared our Mod-MPI values demonstrated poor concordance, especially at 27+0-29+0 weeks'. Pearson interobserver correlation was also improved at 35+0-37+0 weeks' at 0.434, compared with 0.083 at 27+0-29+0 weeks' gestation. CONCLUSIONS: Concordance and interobserver variability between our cohort and similar populations were both improved at 35+0-37+0 weeks' compared with 27+0-29+0 weeks' gestation. Overall, variable Mod-MPI reproducibility across gestations limits clinical application, especially earlier in pregnancy. Manual Mod-MPI measurement should be considered most reliable in late pregnancy until automated MPI measurement is possible.


Asunto(s)
Corazón Fetal/diagnóstico por imagen , Corazón Fetal/fisiología , Indicadores de Salud , Adulto , Estudios de Cohortes , Ecocardiografía Doppler , Femenino , Edad Gestacional , Humanos , Recién Nacido , Estudios Longitudinales , Variaciones Dependientes del Observador , Embarazo , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados , Ultrasonografía Prenatal
13.
J Environ Manage ; 205: 125-133, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28972926

RESUMEN

Mixing is the driver for the energy footprint of water resource recovery in lagoons. With the availability of solar-powered equipment, one potential measure to decrease the environmental impacts of treatment is to transition to an off-the-grid treatment. We studied the comparative scenarios of an existing grid-powered mixer and a solar-powered mixer. Testing was conducted to monitor the water quality, and to guarantee that the effluent concentrations were maintained equally between the two scenarios. Meanwhile, the energy consumption was recorded with the electrical energy monitor by the wastewater treatment utility, and the carbon emission changes were calculated using the emission intensity of the power utility. The results show that after the replacement, both energy usage and energy costs were significantly reduced, with the energy usage having decreased by 70% and its cost by 47%. Additionally, carbon-equivalent emission from electricity importation dropped by 64%, with an effect on the overall carbon emissions (i.e., including all other contributions from the process) decreasing from 3.8% to 1.5%.


Asunto(s)
Huella de Carbono , Energía Solar , Carbono , Electricidad
14.
BMC Med ; 15(1): 164, 2017 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-28854913

RESUMEN

BACKGROUND: While being small-for-gestational-age due to placental insufficiency is a major risk factor for stillbirth, 50% of stillbirths occur in appropriate-for-gestational-age (AGA, > 10th centile) fetuses. AGA fetuses are plausibly also at risk of stillbirth if placental insufficiency is present. Such fetuses may be expected to demonstrate declining growth trajectory across pregnancy, although they do not fall below the 10th centile before birth. We investigated whether reduced growth velocity in AGA fetuses is associated with antenatal, intrapartum and neonatal indicators of placental insufficiency. METHODS: We performed a prospective cohort study of 308 nulliparous women who subsequently gave birth to AGA infants. Ultrasound was utilised at 28 and 36 weeks' gestation to determine estimated fetal weight (EFW) and abdominal circumference (AC). We correlated relative EFW and AC growth velocities with three clinical indicators of placental insufficiency, namely (1) fetal cerebroplacental ratio (CPR; CPR < 5th centile reflects placental resistance, and blood flow redistribution to the brain - a fetal response to hypoxia); (2) neonatal acidosis after the hypoxic challenge of labour (umbilical artery (UA) pH < 7.15 at birth); and (3) low neonatal body fat percentage (BF%, measured by air displacement plethysmography) reflecting reduced nutritional reserve in utero. RESULTS: For each one centile reduction in EFW growth velocity between 28 and 36 weeks' gestation, there was a 2.4% increase in the odds of cerebral redistribution (CPR < 5th centile, odds ratio (OR) (95% confidence interval) = 1.024 (1.005-1.042), P = 0.012) and neonatal acidosis (UA pH < 7.15, OR = 1.024 (1.003-1.046), P = 0.023), and a 3.3% increase in the odds of low BF% (OR = 1.033 (1.001-1.067), P = 0.047). A decline in EFW of > 30 centiles between 28 and 36 weeks (compared to greater relative growth) was associated with cerebral redistribution (CPR < 5th centile relative risk (RR) = 2.80 (1.25-6.25), P = 0.026), and a decline of > 35 centiles was associated with neonatal acidosis (UA pH < 7.15 RR = 3.51 (1.40-8.77), P = 0.030). Similar associations were identified between low AC growth velocity and clinical indicators of placental insufficiency. CONCLUSIONS: Reduced growth velocity between 28 and 36 weeks' gestation among fetuses born AGA is associated with antenatal, intrapartum and neonatal indicators of placental insufficiency. These fetuses potentially represent an important unrecognised cohort at increased risk of stillbirth and may warrant more intensive antenatal surveillance.


Asunto(s)
Peso al Nacer , Retardo del Crecimiento Fetal , Insuficiencia Placentaria , Tercer Trimestre del Embarazo , Adulto , Estudios de Cohortes , Femenino , Desarrollo Fetal , Peso Fetal , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Estudios Prospectivos
15.
Prenat Diagn ; 37(6): 611-627, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28444780

RESUMEN

OBJECTIVE: This study aimed to determine the additional diagnostic information provided by prenatal (fetal) magnetic resonance imaging (pMRI) following tertiary ultrasound (US) for fetal cranial abnormalities in complicated monochorionic gestations. METHODS: Women with complicated monochorionic gestations complicated by twin-twin transfusion syndrome, co-twin demise (CD), selective intrauterine growth restriction, and/or twin anaemia-polycythaemia sequence who were referred for pMRI after tertiary US were included. Additional diagnostic information by pMRI that changed prognostic counselling was the primary outcome. RESULTS: Thirty-three women with 48 live fetuses had pMRI at a median of 25 weeks (range: 21-29). Three of ten survivors of spontaneous CD, one of eight survivors of CD after twin-twin transfusion syndrome and 1/30 co-survivors had diagnostic information added by pMRI that altered counselling; US was normal in two and in the other three underrepresented parenchymal injury (5/33 = 15%; 95% confidence interval ±0.27-0.03). Additional findings included occipital lobe infarction, hemispheric injury, dural sinus thrombosis, ischaemia-producing polymicrogyria and intraventricular haemorrhage. Another 8/33 women had additional information provided by pMRI that did not alter counselling. CONCLUSION: Prenatal magnetic resonance imaging resulted in changed prognostic counselling in 5/33 pregnancies. Evaluation of incorporation of pMRI into routine surveillance of complicated monochorionic gestations is needed. © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Lesiones Encefálicas/diagnóstico por imagen , Enfermedades Fetales/diagnóstico por imagen , Transfusión Feto-Fetal/diagnóstico por imagen , Imagen por Resonancia Magnética/estadística & datos numéricos , Femenino , Humanos , Embarazo , Estudios Retrospectivos , Gemelos Monocigóticos , Ultrasonografía Prenatal
16.
Environ Sci Technol ; 50(22): 12166-12178, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27804303

RESUMEN

The Intergovernmental Panel on Climate Change (IPCC) reported that all carbon dioxide (CO2) emissions generated by water resource recovery facilities (WRRFs) during treatment are modern, based on available literature. Therefore, such emissions were omitted from IPCC's greenhouse gas (GHG) accounting procedures. However, a fraction of wastewater's carbon is fossil in origin. We hypothesized that since the fossil carbon entering municipal WRRFs is mostly from soaps and detergents as dissolved organic matter, its fate can be selectively determined during the universally applied separation treatment processes. Analyzing radiocarbon at different treatment points within municipal WRRFs, we verified that the fossil content could amount to 28% in primary influent and showed varying distribution leaving different unit operations. We recorded the highest proportion of fossil carbon leaving the secondary treatment as off-gas and as solid sludge (averaged 2.08 kg fossil-CO2-emission-potential m-3 wastewater treated). By including fossil CO2, total GHG emission in municipal WRRFs increased 13%, and 23% if an on-site energy recovery system exists although much of the postdigestion fossil carbon remained in biosolids rather than in biogas, offering yet another carbon sequestration opportunity during biosolids handling. In comparison, fossil carbon contribution to GHG emission can span from negligible to substantial in different types of industrial WRRFs. With such a considerable impact, CO2 should be analyzed for each WRRF and not omitted from GHG accounting.


Asunto(s)
Carbono , Recursos Hídricos , Dióxido de Carbono , Cambio Climático , Fósiles , Efecto Invernadero , Aguas del Alcantarillado
17.
J Ultrasound Med ; 35(4): 717-22, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26931786

RESUMEN

OBJECTIVES: The purpose of this study was to determine whether routine direct visualization of the corpus callosum is achievable during second-trimester sonography when performed by a large group of sonographers in a general second-trimester sonographic screening program. The secondary aim was to determine the time taken to obtain a sagittal corpus callosum image. METHODS: We conducted a retrospective cohort study of visualization of the corpus callosum before and after intensive training. Images from 150 consecutive second-trimester scans were reviewed before and after training to evaluate the image quality of the corpus callosum. RESULTS: A total of 300 cases were evaluated before and after training. There was a significant increase in the rate of complete visualization of the corpus callosum after intensive training (P < .0001). Before training 35 of 150 cases (23%) had complete visualization of the corpus callosum versus 107 of 150 (71%) after training. The mean time to perform the corpus callosum views was 53.4 seconds before training compared to 56.2 seconds after training. CONCLUSIONS: Assessing the corpus callosum in the sagittal view is difficult and requires appropriate training and patience; however, this view is feasible without adding substantial time to the examination and provides additional information during a routine second-trimester morphologic scan.


Asunto(s)
Agenesia del Cuerpo Calloso/epidemiología , Competencia Clínica/estadística & datos numéricos , Capacitación en Servicio/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Ultrasonografía Prenatal/estadística & datos numéricos , Agenesia del Cuerpo Calloso/diagnóstico por imagen , Australia/epidemiología , Estudios de Cohortes , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Embarazo , Segundo Trimestre del Embarazo , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad
18.
J Exp Biol ; 217(Pt 21): 3898-909, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25189374

RESUMEN

The aerodynamics of flapping flight for the smallest insects such as thrips is often characterized by a 'clap and fling' of the wings at the end of the upstroke and the beginning of the downstroke. These insects fly at Reynolds numbers (Re) of the order of 10 or less where viscous effects are significant. Although this wing motion is known to augment the lift generated during flight, the drag required to fling the wings apart at this scale is an order of magnitude larger than the corresponding force acting on a single wing. As the opposing forces acting normal to each wing nearly cancel during the fling, these large forces do not have a clear aerodynamic benefit. If flight efficiency is defined as the ratio of lift to drag, the clap and fling motion dramatically reduces efficiency relative to the case of wings that do not aerodynamically interact. In this paper, the effect of a bristled wing characteristic of many of these insects was investigated using computational fluid dynamics. We performed 2D numerical simulations using a porous version of the immersed boundary method. Given the computational complexity involved in modeling flow through exact descriptions of bristled wings, the wing was modeled as a homogeneous porous layer as a first approximation. High-speed video recordings of free-flying thrips in take-off flight were captured in the laboratory, and an analysis of the wing kinematics was performed. This information was used for the estimation of input parameters for the simulations. Compared with a solid wing (without bristles), the results of the study show that the porous nature of the wings contributes largely to drag reduction across the Re range explored. The aerodynamic efficiency, calculated as the ratio of lift to drag coefficients, was larger for some porosities when compared with solid wings.


Asunto(s)
Vuelo Animal/fisiología , Modelos Biológicos , Thysanoptera/fisiología , Alas de Animales/fisiología , Animales , Fenómenos Biomecánicos , Hidrodinámica , Grabación en Video , Alas de Animales/anatomía & histología
19.
Water Res ; 47(14): 5189-99, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23863383

RESUMEN

Laser flash photolysis (LFP) was used to characterize a triplet excited state species isolated from Black River and San Joaquin wetlands particulate organic matter (POM). The solubilized organic matter, isolated from POM by pH-independent diffusion in distilled water, was named PdOM. UV-visible absorption spectroscopy, excitation-emission matrix spectroscopy (EEMs), and (1)H NMR were used to characterize the PdOM. While LFP of dissolved organic matter (DOM) is known to generate the solvated electron, LFP of the PdOM transient in argon-, air-, and nitrous oxide-saturated solutions indicated that this was a triplet excited state species ((3)PdOM*). The lifetime and the reactivity of (3)PdOM* with sorbic acid, a triplet state quencher, were compared with that of the triplet excited state of benzophenone, a DOM proxy. A second excited state species (designated DOM*), with a longer lifetime, was reported in a number of previous studies but not characterized. The lifetime of DOM*, measured for seventeen organic matter isolates, lignin, tannic acid, and three wetlands plant extracts, was shown to differentiate allochthonous from autochthonous DOM. (3)POM* and DOM* were also observed in lake water and a constructed wetlands' water. Aqueous extracts of fresh and aged plant material from the same wetland were shown to be one source of these excited state species. This study provides evidence of a role for POM in the photochemistry of natural and constructed wetland waters.


Asunto(s)
Agua Dulce/química , Fotoquímica , Benzofenonas/química , California , Clorofila , Clorofila A , Rayos Láser , Lignina/química , Espectroscopía de Resonancia Magnética , Tamaño de la Partícula , Fotólisis , Plantas/química , Ríos/química , Ácido Sórbico/química , Espectrometría de Fluorescencia/métodos , Taninos/química , Humedales
20.
Aust N Z J Obstet Gynaecol ; 52(2): 156-60, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22369139

RESUMEN

BACKGROUND: A low-lying placenta detected at the mid-pregnancy ultrasound is commonly reported to warn against potential morbidity associated with placenta praevia. There is no information on what distance away from the internal cervical os is safe. AIMS: We examined whether a low-lying placenta not overlapping the cervical os in the second trimester increases the risk of obstetric complications and whether there is a cut-off point at which that increase occurs. METHODS: Adverse perinatal outcomes were examined prospectively in a cohort of women with a placenta 0-30 mm from the internal cervical os ('low-lying') at the routine mid-trimester ultrasound and compared to those with a placenta further away. Two composite outcomes of 'major' and 'minor' adverse events were predefined as primary outcome measures, requiring a sample size of 480 women with a low-lying placenta. Chi-square and Fisher's exact tests were used for statistical analysis. RESULTS: In 1662 pregnancies ('low-lying': n = 484; 'normal': n = 1178), there was no increase in composite adverse outcomes with a low-lying placenta and no cut-off distance within 30 mm from the cervical os at which risks increased. Postpartum haemorrhage ≥ 1000 mL was more frequent with a low-lying placenta (7.6% vs 4.7%, P < 0.05). CONCLUSIONS: Women with a low-lying placenta, not overlapping the cervical os, in mid-pregnancy are at no higher risk of adverse outcomes than those with a normally located placenta, except postpartum haemorrhage. This suggests that the high-risk label can be removed from pregnancies with a low-lying placenta not overlapping the cervical os in mid-pregnancy, reducing anxiety and resource utilisation.


Asunto(s)
Placenta Previa/diagnóstico por imagen , Resultado del Embarazo/epidemiología , Adulto , Femenino , Humanos , Placenta/diagnóstico por imagen , Embarazo , Segundo Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal , Adulto Joven
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