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The recent Society for Maternal-Fetal Medicine Consult Series #65 provides a comprehensive review of transabdominal cerclage. The current article condenses the Consult recommendations regarding patient selection, counseling, and management into 2 simple one-page checklists, one for the primary obstetrical provider and the other for the maternal-fetal medicine consultant or cerclage provider. Moreover, we provide sample templates for medical record notes to document preprocedure counseling and informed consent.
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The frequency of telemedicine encounters has increased dramatically in recent years. This review summarizes the literature regarding the safety and quality of telemedicine for pregnancy-related services, including prenatal care, postpartum care, diabetes mellitus management, medication abortion, lactation support, hypertension management, genetic counseling, ultrasound examination, contraception, and mental health services. For many of these, telemedicine has several potential or proven benefits, including expanded patient access, improved patient satisfaction, decreased disparities in care delivery, and health outcomes at least comparable to those of traditional in-person encounters. Considering these benefits, it is suggested that payers should reimburse providers at least as much for telemedicine as for in-person services. Areas for future research are considered.
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Obstetricia , Telemedicina , Embarazo , Femenino , Humanos , Perinatología , Anticoncepción , Atención PrenatalRESUMEN
The Centers for Disease Control and Prevention define social determinants of health as "the conditions in the places where people live, learn, work, and play" that can affect health outcomes. Systemic racism is a root cause of the power and wealth imbalances that affect social determinants of health, creating disproportionate rates of comorbidities and adverse outcomes in the communities of racial and ethnic minority groups. Focusing primarily on disparities between Black and White individuals born in the United States, this document reviews the effects of social determinants of health and systemic racism on reproductive health outcomes and recommends multilevel approaches to mitigate disparities in obstetrical outcomes.
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Etnicidad , Grupos Minoritarios , Femenino , Disparidades en Atención de Salud , Humanos , Perinatología , Determinantes Sociales de la Salud , Racismo Sistemático , Estados UnidosRESUMEN
The processes of diagnosis and management involve clinical decision-making. However, decision-making is often affected by cognitive biases that can lead to medical errors. This statement presents a framework of clinical thinking and decision-making and shows how these processes can be bias-prone. We review examples of cognitive bias in obstetrics and introduce debiasing tools and strategies. When an adverse event or near miss is reviewed, the concept of a cognitive autopsy-a root cause analysis of medical decision-making and the potential influence of cognitive biases-is promoted as part of the review process. Finally, areas for future research on cognitive bias in obstetrics are suggested.
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Cognición , Errores Médicos , Obstetricia , Sesgo , Humanos , Perinatología , Sociedades Médicas , Estados UnidosRESUMEN
The management of pregnancies resulting from in vitro fertilization includes several recommended interventions at various times by various providers. To minimize the chance of errors of omission, the Society for Maternal-Fetal Medicine presents a patient-oriented checklist summarizing the recommended management of such pregnancies.
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Lista de Verificación , Perinatología , Femenino , Fertilización In Vitro , Humanos , EmbarazoRESUMEN
Recent surveys have shown widespread lapses in the procedures used to reduce the risk of transmitting infection via medical devices. Transvaginal ultrasound examination has the potential to transmit vaginal infections, including human papillomavirus. Areas of particular concern are the use of probe covers with high rates of leakage, disinfectants that are not effective against human papillomavirus, and coupling gel from multiple-use containers. We reviewed these issues, and we recommend 4 steps to reduce the risk of transmitting infection. First, during every transvaginal ultrasound exam, the probe should be covered with a sterile, single-use "viral barrier" cover or a condom. Second, sterile, single-use ultrasound gel packets should be used. Third, after every examination, the probe should be cleaned to remove any visible gel or debris. Finally, after cleaning, the probe should undergo high-level disinfection using an agent with proven efficacy against the human papillomavirus, including hydrogen peroxide, hypochlorite, or peracetic acid. Glutaraldehyde, orthophthalaldehyde, phenols, and isopropyl alcohol have virtually no efficacy against the human papillomavirus.
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Transmisión de Enfermedad Infecciosa/prevención & control , Contaminación de Equipos/prevención & control , Ultrasonografía Prenatal/instrumentación , Enfermedades Vaginales/microbiología , Enfermedades Vaginales/prevención & control , Desinfectantes , Desinfección/métodos , Equipos Desechables , Femenino , Glutaral , Humanos , Control de Infecciones/métodos , Infecciones por Papillomavirus/prevención & control , Embarazo , Esterilización/métodos , Ultrasonografía Prenatal/efectos adversos , Enfermedades Vaginales/virología , o-FtalaldehídoRESUMEN
There are many organizations in the United States concerned with the improvement of patient safety and healthcare quality. In this overview, we provide a synopsis of the major entities whose work is relevant to maternal healthcare. For each organization, we summarize its mission, vision, major programs, and relationships with other entities. We include 13 entities with broad scope covering all types of healthcare; 9 organizations whose focus is maternal-child health; 6 women's health professional organizations with committees on patient safety, quality, or both; 12 organizations that offer accreditation, certification, or special distinction based on quality; and 5 organizations that rate, rank, or report quality metrics.
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Servicios de Salud Materna/normas , Organizaciones , Seguridad del Paciente , Calidad de la Atención de Salud , Humanos , Agencias Internacionales , Estados UnidosRESUMEN
BACKGROUND: Severe maternal morbidity (SMM) prevalence was 194.0 per 10 000 deliveries in Texas in 2015. Chronic, behavioral, and pregnancy-induced conditions, as captured by a maternal comorbidity index, increase the risk for delivery-related morbidity and mortality. The objective of the study was to examine the association between maternal comorbidity index and SMM among delivery hospitalizations in Texas. METHODS: Delivery-related hospitalizations among Texan women aged 15-49 years were identified using the 2011-2014 Texas all-payer inpatient hospitalization public use data files (n = 1 434 441). The primary outcome of interest was SMM, based on the Alliance for Innovation on Maternal Health's coding scheme. The exposure of interest was a maternal comorbidity index. Multivariable logistic regression model was used to examine the association between maternal comorbidity index and SMM. RESULTS: SMM prevalence remained consistent between 2011 and 2014 (196.0-197.0 per 10 000 deliveries, P > .05; n = 1 434 441). Nearly 40% of delivery-related hospitalizations had a maternal comorbidity index of at least 1, and the proportion of deliveries in the highest risk category of comorbidity index (≥5) increased by 12.0% from 2011 to 2014. SMM prevalence was highest among the youngest and oldest age groups. With each unit increase in maternal comorbidity index, the odds of SMM increase was 1.43 (95% CI 1.42-1.43). CONCLUSIONS: Maternal comorbidity index is associated with SMM; however, the low predictive power of the model suggests that other, unmeasured factors may influence SMM in Texas. These findings highlight a need to understand broader contextual factors (practitioner, facility, systems of care, and community) that may be associated with SMM to reduce maternal morbidity and mortality in Texas.
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Mortalidad Materna/tendencias , Morbilidad/tendencias , Complicaciones del Embarazo/mortalidad , Adolescente , Adulto , Comorbilidad , Estudios Transversales , Femenino , Hospitalización , Humanos , Modelos Logísticos , Edad Materna , Persona de Mediana Edad , Análisis Multivariante , Embarazo , Complicaciones del Embarazo/epidemiología , Prevalencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Texas/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Higher mortality rates have been reported in patients admitted to the hospital on weekends. This study aimed to compare maternal mortality ratio (MMR), fetal mortality ratio, and other maternal and neonatal outcomes by day of death or delivery in the United States. METHODS: Our database consisted of a population-level analysis of live births and maternal and fetal deaths between 2004 and 2014 in the United States from the Centers for Disease Control and Prevention's National Center for Health Statistics. We also examined the relationship between these deaths and various documented maternal and fetal clinical conditions. RESULTS: A total of 2,061 maternal deaths occurred on weekends and 5,510 deaths on weekdays. During the same period of time, 65,063 and 210,851 cases of fetal demise were delivered on weekends and on weekdays, respectively. Maternal mortality was significantly higher on weekends than weekdays (22.9 vs. 15.3/100,000 live births, p < 0.001) as was fetal mortality (7.21 vs. 5.85/100,000, p < 0.001), despite a lower frequency of serious comorbidities among women delivering on weekends. CONCLUSION: Our data demonstrate a significant increase in the U.S. MMR and stillbirth delivery on weekends. Relative representation of antepartum, intrapartum, and postpartum deaths cannot be ascertained from these data.
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Muerte Fetal , Mortalidad Hospitalaria , Mortalidad Materna , Mortinato/epidemiología , Adulto , Femenino , Humanos , Nacimiento Vivo/epidemiología , Complicaciones del Trabajo de Parto/epidemiología , Embarazo , Complicaciones del Embarazo/epidemiología , Estados Unidos/epidemiologíaRESUMEN
OBJECTIVES: To assess short-term neonatal respiratory morbidity from inductions of labor (IOL) in well-dated (WD) pregnancies (dating ultrasound [US] <20 0/7 weeks) versus non-well-dated (NWD) pregnancies when applying National Institutes of Health/Society for Maternal-Fetal Medicine/American College of Obstetricians and Gynecologists delivery recommendations at ≥34 0/7 weeks. METHODS: Ours was a 1-year retrospective cohort of women with medically indicated IOL between 34 0/7 and 40 6/7 weeks with a live, cephalic, singleton gestation and no lethal anomaly. The primary outcome was a composite of neonatal respiratory morbidity (respiratory distress syndrome, transient tachypnea of the newborn, ventilator support, oxygen administration, and pneumonia). RESULTS: A total of 476 WD and 231 NWD women underwent IOL during the study period. The groups had similar maternal characteristics, indications for IOL, and mode of delivery. There was no difference in the rate of primary outcome (8.7% in NWD group vs 8.8% in WD group; P = 0.95). This finding persisted after control for parity, gestational age (GA) at first US, operator of the dating US, and exposure to antenatal corticosteroids and magnesium sulfate. When stratified by GA at delivery and GA at first US, these findings persisted even when the dating US was performed at >35 weeks. There were no differences in maternal or other neonatal outcomes between the WD and NWD pregnancies. CONCLUSIONS: In our cohort of medically indicated IOL, a dating US before 20 weeks was not associated with a difference in neonatal respiratory morbidity.
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Edad Gestacional , Trabajo de Parto Inducido/métodos , Adulto , Estudios de Cohortes , Parto Obstétrico , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía PrenatalRESUMEN
OBJECTIVE: The purpose of this study was to determine whether adherence to an induction of labor (IOL) protocol decreases the rate of failed IOL (FIOL). STUDY DESIGN: We performed a 1-year retrospective chart review around the implementation of a hospital IOL protocol and compared maternal and neonatal outcomes from deliveries managed per protocol (n = 369) with those deliveries that were not (n = 230). Women at least 24 weeks' gestation with cervical dilation up to 2 cm who underwent an indicated IOL were included. Protocol-adherent (PA) inductions had amniotomy within 24 hours of starting oxytocin, intrauterine pressure catheter placement in latent labor, Montevideo units titrated to 200-300 or to adequate cervical change, and oxytocin administered for at least 12 hours after amniotomy before FIOL was diagnosed (defined as delivery by cesarean during latent labor as a result of failure to enter active labor). The primary outcome was the rate of FIOL. Control for possible confounders was made by stratification and multivariate modeling. RESULTS: FIOL rates were lowest in the PA group, which remained significant after stratification on parity and multivariate analysis (nulliparous women, 3.8% vs 9.8%; P = .043; multiparous women, 0% vs 6%; P < .0004). Median time to delivery was shortest in the PA group by 3.5 hours in nulliparous women (16.0 vs 19.5 hours, respectively; P = .0002) and 1.5 hours in multiparous women (10.75 vs 12.25 hours, respectively; P < .0001). There were no differences in infectious morbidity or neonatal outcomes between the groups. CONCLUSION: Adherence to a standardized IOL protocol is associated with a decreased rate of FIOL and length of labor.
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Trabajo de Parto Inducido/normas , Adulto , Protocolos Clínicos , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Paridad , Embarazo , Resultado del Embarazo , Estudios RetrospectivosRESUMEN
OBJECTIVE: To test the hypothesis that a hemoglobin A1C value (A1C) in early pregnancy is predictive of overt diabetes mellitus (DM) postpartum in women with gestational diabetes (GDM). STUDY DESIGN: In this case-control analysis of women with an early pregnancy diagnosis of GDM, we estimated the association between an early pregnancy A1C and subsequent diagnosis of DM. Women with a normal postpartum diabetic screen (controls) were compared against those with confirmed postpartum DM (cases). Ability of A1C levels to predict DM was examined via logistic regression analysis and corresponding receiver operating characteristic values. RESULTS: During the 10-year study period 166 women met the inclusion criteria: 140 (84%) had normal postpartum testing (controls), and 26 (16%) were diagnosed with DM (cases). The mean A1C value was significantly higher among cases than controls (6.7 vs. 5.6, p < 0.0001, SD 1.3-5). Cases had A1Cs ranging from 5.5- 11.7%, while controls had A1Cs ranging from 4.3-7.8%. The best discriminatory cut point for postpartum DM was an A1C > 5.9% (sensitivity 81%, specificity 83%, positive predictive value 47%, negative predictive value CONCLUSION: Our findings suggest that an elevated early pregnancy A1C may be predictive of overt DM. Larger studies are needed to further validate this association.
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Diabetes Mellitus/sangre , Diabetes Mellitus/diagnóstico , Diabetes Gestacional/sangre , Hemoglobina Glucada/análisis , Adulto , Glucemia/análisis , Estudios de Casos y Controles , Ayuno/sangre , Femenino , Humanos , Modelos Logísticos , Periodo Posparto/sangre , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo/sangre , Segundo Trimestre del Embarazo/sangre , Curva ROC , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To determine if an association exists between Montevideo units (MVUs) and uterine rupture in women undergoing trial of labor after cesarean (TOLAC). STUDY DESIGN: A case-control study of women who underwent a TOLAC, comparing uterine rupture (n = 9) to successful vaginal birth after cesarean (VBAC) (n = 48) and failed TOLAC (n = 35). MVUs were calculated in 12 10-minute intervals prior to uterine rupture, cesarean delivery, or complete dilation in the VBAC group. MVUs were compared between groups by Wilcoxon rank sum test. The pattern of change of MVUs over time was examined by linear regression mixed models. RESULTS: The MVUs were similar among all groups (medians ranged from 140-175 [VBAC], 145-190 [TOLAC], and 130-195 [ruptures]). The analysis of pattern of change in MVUs over time demonstrated no difference within the VBAC group (p = 0.22) or the failed TOLAC group (p = 0.87), or between groups (VBAC and rupture [p = 0.56], failed TOLAC and rupture [p = 0.37]). A post-hoc power analysis showed a mean difference of 50 MVUs (SD 45) between VBAC and rupture and 55 MVUs (SD 45) between failed TOLAC and rupture can be detected with a power of 80% at a significance of 0.05. CONCLUSION: There is no association between MVUs and uterine rupture in women undergoing a TOLAC.
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Esfuerzo de Parto , Contracción Uterina/fisiología , Rotura Uterina/epidemiología , Parto Vaginal Después de Cesárea , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Estudios Retrospectivos , Adulto JovenRESUMEN
Previous work has shown that caregiver attention shapes visual cognition in infants through dyadic interactions. Is this association measurable when visual cognition is objectively measured in caregivers and infants using comparable experimental paradigms? In the current study, we presented infants (N = 86) and caregivers (N = 78) with age-specific variants of the same preferential looking visual cognition task to investigate whether caregiver visual cognition was associated with their infants' visual cognition. In each trial of the task, two side-by-side flashing displays of coloured shapes were presented. On the 'unchanging' side, the colours of the shapes remained the same. On the 'changing' side, the colour of one shape changed after each flash. Load was varied by changing the number of shapes across trials (low, medium, and high loads). We extracted looking dynamics using video recordings and brain function using functional near-infrared spectroscopy as both infants and caregivers engaged with the task. Change preference (CP) score, which represented the amount of time spent looking at the changing side divided by the total looking duration, showed a load-dependent modulation for both infants and caregivers. Both groups showed the highest CP scores at the low load. Further, higher caregiver CP scores was associated with higher infant CP scores at the low load. Both infants and caregivers engaged canonical regions of the fronto-parietal network involved in visual cognition. Critically, higher caregiver CP scores were associated with greater activation in the left superior parietal lobule in younger infants, a region involved in allocating visuo-spatial attention and working memory maintenance. Further, there was spatial overlap between performance-dependent regions in the right parietal cortex in caregivers and younger infants. Our findings provide first evidence of a heritability-related visual neurocognitive association between caregivers and their children in the first year of life.
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Visual working memory (VWM) emerges in the first year of life and has far-reaching implications for academic and later life outcomes. Given that caregivers play a significant role in shaping cognitive function in children, it is important to understand how they might impact VWM development as early as infancy. The current study investigated whether caregivers' efficiency of regulating inhibitory control was associated with VWM function in their infants. Eighty-eight caregivers were presented with a Go-NoGo task to assess inhibitory control. An efficiency score was calculated using their behavioural responses. Eighty-six 6-to-10-month-old infants were presented with a preferential looking task to assess VWM function. VWM load was manipulated across one (low load), two (medium load) and three (high load) items. Functional near-infrared spectroscopy was used to record brain activation from caregivers and their infants. We found no direct association between caregiver efficiency and infant VWM behaviour. However, we found an indirect association - caregiver efficiency was linked to infant VWM through left-lateralized fronto-parietal engagement. Specifically, infants with low efficiency caregivers showed decreasing left-lateralized parietal engagement with increasing VWM performance at the medium and high loads compared to infants with high efficiency caregivers, who did not show any load- or performance-dependent modulation. Our findings contribute to a growing body of literature examining the role that caregivers play in early neurocognitive development.
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Cuidadores , Memoria a Corto Plazo , Niño , Lactante , Humanos , Memoria a Corto Plazo/fisiología , Encéfalo/fisiología , Cognición , Percepción Visual/fisiologíaRESUMEN
Neurocognition and academic abilities during the period of 4 and 7 years of age are impacted by both the transition from kindergarten to primary school and age-related developmental processes. Here, we used a school cut-off design to tease apart the impact of formal schooling from age, on working memory (WM) function, vocabulary, and numeracy scores. We compared two groups of children with similar age, across two years: first-graders (FG), who were enrolled into primary school the year that they became eligible and kindergarteners (KG), who were deferred school entry until the following year. All children completed a change detection task while brain activation was recorded using portable functional near-infrared spectroscopy, a vocabulary assessment, and a numeracy screener. Our results revealed that FG children showed greater improvement in WM performance and greater engagement of a left-lateralized fronto-parietal network compared to KG children. Further, they also showed higher gains in vocabulary and non-symbolic numeracy scores. This improvement in vocabulary and non-symbolic numeracy scores following a year in primary school was predicted by WM function. Our findings contribute to a growing body of literature examining neurocognitive and academic benefits conferred to children following exposure to formal schooling.
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Memoria a Corto Plazo , Instituciones Académicas , Niño , Humanos , Preescolar , Memoria a Corto Plazo/fisiología , Escolaridad , Cognición , EncéfaloRESUMEN
Due to the overall low abundance of volatile compounds in exhaled breath, it is necessary to preconcentrate the sample prior to traditional thermal desorption (TD) gas chromatography mass spectrometry analysis. While certain aspects of TD tubes, such as volatile storage, have been evaluated, many aspects remain uncharacterized. Two common TD tubes, Tenax TA and Biomonitoring 5TD tubes, were evaluated for background content and flow rate variability. The data illustrate that the Biomonitoring 5TD tubes have the highest number (23) and abundance of background contamination greater than 3x the mean noise when compared to Tenax TA (13) and empty tubes (9). Tentative identifications of the compounds in the background contamination experiment show that greater than 59% (16/27) of the compounds identified have been reported in the breath literature. The data illustrate the TD tube background abundance could account for more than 70% of the chromatographic signal from exhaled breath for these select compounds. Flow rate measurements of 200 Tenax TA and 200 Biomonitoring 5TD tubes show a large range in measured flow rates among the TD tubes (Tenax: 252.9-284.0 ml min-1, 5TD: 220.6-255.1 ml min-1). Finally, TD tubes of each type, Tenax TA and Biomonitoring 5TD, previously established to have high, medium, and low flow rates, show insignificant differences (p> 0.05) among the tubes of different flow rates, using both gas standards and an exhaled breath from a peppermint experiment. Collectively, these results establish overall background compounds attributed to each TD tube type tested. Additionally, while measured flow rate variability is present and plausibly impacts exhaled breath results, the data demonstrate no statistically significant difference was observed between tubes showing high, medium, and low flow rates from two separate sample types.
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Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Pruebas Respiratorias/métodos , Espiración , Cromatografía de Gases y Espectrometría de Masas/métodos , Estándares de ReferenciaRESUMEN
Exhaled breath research has been hindered by a lack of standardization in collection and analysis methodologies. Recently, the Respiration Collector forIn VitroAnalysis (ReCIVA) sampling device has illustrated the potential to provide a consistent and convenient method for exhaled breath collection onto adsorbent media. However, the significant costs, compared to exhaled breath bags, associated with the standardized collector is believed to be the reason for limited widespread use by researchers in the exhaled breath field. For example, in addition to the sampling hardware, a single-use disposable silicon mask affixed with a filter is required for each exhaled breath collection. To reduce the financial burden, streamline device upkeep, reduce waste material, and ease the logistical burden associated with the single use masks, it is hypothesized that the consumable masks and filters could be sterilized by autoclaving for reuse. The masks were contaminated, autoclaved, and then tested for any surviving pathogens with spore strip standards and by measuring the optical density of cultures. The compound background collected when using the ReCIVA with new masks was compared to that collected with repeatedly autoclaved masks via thermal desorption gas chromatography mass spectrometry (TD-GC-MS). The capacity to block particulate matter of new filters was tested against that of autoclaved filters by introducing an aerosol and comparing pre-filter and post-filter particle counts. Finally, breath samplings were conducted with new masks and autoclaved masks to test for changes in measurements by TD-GC-MS of exogenous and endogenous compounds. The data illustrate the autoclave cycle sterilizes masks spiked with saliva to background levels (p= 0.2527). The results indicate that background levels of siloxane compounds are increased as masks are repetitively autoclaved. The data show that mask filters have significant breakthrough of 1µm particles after five repetitive autoclaving cycles compared to new filters (p= 0.0219). Finally, exhaled breath results utilizing a peppermint ingestion protocol indicate two compounds associated with peppermint, menthone and 1-Methyl-4-(1-methylethyl)-cyclohexanol, and an endogenous exhaled breath compound, isoprene, show no significant difference if sampled with a new mask or a mask autoclaved five times (p> 0.1063). Collectively, the data indicate that ReCIVA masks and filters can be sterilized via autoclave and reused. The results suggest ReCIVA mask and filter reuse should be limited to three times to limit potentially problematic background contaminants and filter dysfunction.
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Pruebas Respiratorias , Esterilización , Humanos , Pruebas Respiratorias/métodos , Cromatografía de Gases y Espectrometría de Masas , Espiración , Estándares de ReferenciaRESUMEN
Isoprene is one of the most abundant and most frequently evaluated volatile organic compounds in exhaled breath. Recently, several individuals with background levels of exhaled isoprene have been identified. Here, case study data are provided for an individual, identified from a previous study, with this low prevalence phenotype. It is hypothesized that the individual will illustrate low levels of exhaled isoprene at rest and during exercise. At rest, the subject (7.1 ppb) shows background (µ= 14.2 ± 7.0 ppb) levels of exhaled isoprene while the control group illustrates significantly higher quantities (µ= 266.2 ± 72.3 ppb) via proton transfer reaction mass spectrometry (PTR-MS). The result, background levels of isoprene at rest, is verified by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) collections with the individual showing -3.6 ppb exhaled isoprene while the room background containedµ= -4.1 ± 0.1 ppb isoprene. As isoprene has been shown previously to increase at the initiation of exercise, exercise bike experiments were performed with the individual identified with low isoprene, yielding low and invariant levels of exhaled isoprene (µ= 6.6 ± 0.1 ppb) during the exercise while control subjects illustrated an approximate 2.5-fold increase (preµ= 286.3 ± 43.8 ppb, exerciseµ= 573.0 ± 147.8 ppb) in exhaled isoprene upon exercise start. Additionally, exhaled breath bag data showed a significant decrease in isoprene (delta post/pre, p = 0.0078) of the control group following the exercise regimen. Finally, TD-GC-MS results for exhaled isoprene from the individual's family (mother, father, sister and maternal grandmother) illustrated that the mother and father exhibited isoprene values (28.5 ppb, 77.2 ppb) below control samples 95% confidence interval (µ= 166.8 ± 43.3 ppb) while the individual's sister (182.0 ppb) was within the control range. These data provide evidence for a large dynamic range in exhaled isoprene in this family. Collectively, these results provide additional data surrounding the existence of a small population of individuals with background levels of exhaled isoprene.
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Pruebas Respiratorias , Butadienos , Pruebas Respiratorias/métodos , Espectrometría de Masas/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Butadienos/análisis , Hemiterpenos/análisis , EspiraciónRESUMEN
BACKGROUND: A common and severe neural tube defect (NTD) phenotype, myelomeningocele (MM), results from the defective closure of the caudal end of the neural tube with herniation of the spinal cord and meninges through the vertebral column. The exact mechanisms for NTDs are unknown, but excessive oxidative stress, particularly in association with maternal diabetes, has been postulated as a mechanism for MM. METHODS: The SNPlex Genotyping (ABI, Foster City, CA) platform was used to investigate single nucleotide polymorphisms (SNPs) across the superoxide dismutase (SOD) 1 and 2 genes to assess their association with MM risk. The study population included 329 trio (affected child and both parents) and 281 duo (affected child and one parent) families. Only cases with documented MM were studied. Seventeen SNPs across the SOD1 and SOD2 genes met the quality-control criteria to be considered for statistical analysis. Genetic association was assessed using the family-based transmission disequilibrium test in PLINK (a genome association analysis toolset). RESULTS: Four SNPs in the SOD1 gene (rs 202446, rs202447, rs4816405, and rs2070424) and one SNP in the SOD2 gene ( rs5746105) [corrected] appeared to be associated with MM risk in our population. After adjusting for multiple testing, these SNPs remained significant. CONCLUSION: This study provides the first genetic evidence to support association of myelomeningocele with superoxide scavenging. The rare alleles of the five specific SNPs within SOD1 and SOD2 appear to confer a protective effect on the susceptibility for MM risk in the MM population tested. Further evaluation of the roles of superoxide scavenging and neural tube development is warranted.