RESUMEN
In an oxidizing environment, the oxide formed on plutonium (Pu) metal is composed of a plutonium dioxide (PuO2) top layer and a thin cubic plutonium sesquioxide (Pu2O3) middle layer. In a reducing environment, the PuO2 layer auto-reduces to cubic Pu2O3. The speed and extent of this conversion depend on the combination of temperature and time. While PuO2 provides a strong diffusion barrier against unwanted Pu corrosion by gaseous species (like hydrogen), Pu2O3 does not, since its crystal structure has chains of oxygen vacancies. The kinetics of the PuO2 reduction are, therefore, of fundamental interest and enable researchers to better protect Pu from corrosion. In this report, the oxygen-diffusion-limited kinetics of the dioxide to sesquioxide conversion were obtained by dynamically heating a PuO2-covered Pu sample from 294 to 418 K in a high-vacuum vessel equipped with an in situ spectroscopic ellipsometer. The physical/chemical constraints in the conversion process were combined with the ellipsometry method of multi-sample analysis to track the percentage of PuO2 and to compute the extent of Pu2O3 formation. The resulting diffusion coefficients were compared against and then combined with complementary literature data to produce a comprehensive set of kinetic parameters for reliably modeling oxide conversion over a larger temperature range than spanned by prior studies. The extracted thermal activation energy barrier (43.7 kJ/mol) and pre-exponential factor (5.0 × 10-10 cm2/s) for the oxygen-diffusion-limited process can be used to accurately model the PuO2 to Pu2O3 transformation in vacuum and/or inert gas applications.
RESUMEN
Repeated administration of high doses of propofol to patients with treatment-resistant depression (TRD) has been shown to produce antidepressant effects in small clinical trials. These effects can be elicited when the patient's EEG burst-suppression ratio (BSR) is maintained at 70-90% for 15 min in repeated treatments. This deep anesthesia domain lies beyond the range of current propofol pharmacokinetic/pharmacodynamic (PK/PD) models. In this study, we adapt the Eleveld model for use at deep anesthesia levels with a BSR endpoint, with the goal of aiding the estimation of the dosage of propofol needed to achieve 70-90% BSR for 15 min. We test the ability of the adapted model to predict BSR for these treatments. Twenty participants underwent 6-9 treatments of high doses of propofol (5-9 of which were included in this analysis) for a total of 115 treatments. To adapt the Eleveld model for this endpoint, we optimized the model parameters Ke0, γ and Ce50. These parameters were then used in the adapted model to estimate second-by-second BSR for each treatment. Estimated BSR was compared with observed BSR for each treatment of each participant. Median absolute performance error (MdAPE) between the estimated and observed BSR (25th-75th percentile) was 6.63 (3.79-12.96) % points and 8.51 (4.32-16.74) % between the estimated and observed treatment duration. This predictive performance is statistically significantly better at predicting BSR compared with the standard Eleveld model at deep anesthesia levels. Our adapted Eleveld model provides a useful tool to aid dosing propofol for high-dose anesthetic treatments for depression.
Asunto(s)
Propofol , Humanos , Anestésicos Intravenosos , Depresión/tratamiento farmacológico , Infusiones IntravenosasRESUMEN
The pointwise mutual information statistic (PMI), which measures how often two words occur together in a document corpus, is a cornerstone of recently proposed popular natural language processing algorithms such as word2vec. PMI and word2vec reveal semantic relationships between words and can be helpful in a range of applications such as document indexing, topic analysis, or document categorization. We use probability theory to demonstrate the relationship between PMI and word2vec. We use the theoretical results to demonstrate how the PMI can be modeled and estimated in a simple and straight forward manner. We further describe how one can obtain standard error estimates that account for within-patient clustering that arises from patterns of repeated words within a patient's health record due to a unique health history. We then demonstrate the usefulness of PMI on the problem of predictive identification of disease from free text notes of electronic health records. Specifically, we use our methods to distinguish those with and without type 2 diabetes mellitus in electronic health record free text data using over 400 000 clinical notes from an academic medical center.
Asunto(s)
Diabetes Mellitus Tipo 2 , Procesamiento de Lenguaje Natural , Algoritmos , Registros Electrónicos de Salud , HumanosRESUMEN
Our current understanding of ocean-atmosphere-cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (last) glacial-interglacial transition, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a sea-level highstand during the last interglacial period that was several metres above present. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode, occurred between 135 ± 1 and 130 ± 2 thousand years ago and was linked with rapid sea-level rise during T-II. Our conclusions are based on new and existing data for T-II and the last interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial-interglacial sea-level rise. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major sea-level rise clearly post-dates Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the last interglacial sea-level peak.
Asunto(s)
Cubierta de Hielo , Agua de Mar/análisis , Regiones Antárticas , Organismos Acuáticos/metabolismo , Océano Atlántico , Clima , Foraminíferos/metabolismo , Historia Antigua , Región Mediterránea , Mar Mediterráneo , Plancton/metabolismo , TemperaturaRESUMEN
STUDY QUESTION: Do the rates at which women transition among different intensities of pregnancy planning vary with age, marital status and race/ethnicity? SUMMARY ANSWER: Rates of transition from low or moderate pregnancy probability groups (PPGs) to higher PPGs vary by age, marital status and race/ethnicity. WHAT IS KNOWN ALREADY: The design of prospective studies of the effects of pre- and peri-conception exposures on fecundity, pregnancy and children's health is challenging because at any specific time only a small percentage of reproductive age women is attempting to conceive. To our knowledge, there has been no population-based, prospective study that repeatedly assessed pregnancy planning, which included women who were not already planning pregnancy at enrollment and whose ages spanned the female reproductive age range. STUDY DESIGN, SIZE, DURATION: A longitudinal study was carried out that repeatedly assessed pregnancy probability in 12 916 women for up to 21 months from January 2009 to September 2010. PARTICIPANTS/MATERIALS, SETTING, METHOD: We analyzed data from the National Children's Study Vanguard Study, a pilot study for a large-scale epidemiological birth cohort study of children and their parents. During the Vanguard Study, investigators followed population-based samples of reproductive age women in each of seven geographically dispersed and diverse study locations over time to identify when they sought to become pregnant, providing a unique opportunity to prospectively assess changes in pregnancy planning in a large sample of US women. At study entry and each follow-up contact, which occurred at 1, 3 or 6 month intervals depending on PPG, a questionnaire was used to assess behavior dimensions of pregnancy planning to assign women to low, moderate, high non-tryer and high tryer PPGs. MAIN RESULTS AND THE ROLE OF CHANCE: Crude rates of pregnancy increased with higher assigned PPG, validating the utility of the instrument. The initial PPG and probabilities of transitioning from low or moderate PPG to higher PPG or pregnancy varied with age, marital status and race/ethnicity. Women aged 25 to <35 years had shorter times to transition to higher PPGs or to pregnant compared with women <25 years. Women who were not currently married had longer times to transition from any initial PPG to pregnant, high tryer or high non-tryer status than currently married women. Non-Hispanic Black (NHB) and Hispanic women had shorter time to transition from low or moderate to high non-tryer than non-Hispanic White (NHW) women. NHB women also had shorter time to transition from low to high tryer than NHW women. High tryers are more likely to be aged 25 to <30 years, to be married, and to be Hispanic, NHB or other race/ethnicity than women in the low PPG. LIMITATIONS, REASONS FOR CAUTION: Loss to follow-up varied by age, marital status and race/ethnicity. Although weights were not developed for the Vanguard study, the self-weighting design minimizes the bias of unweighted analysis. Nonetheless, the SEs for some estimates may be under-estimated. WIDER IMPLICATIONS OF THE FINDINGS: Our results show that demographic characteristics are strong predictors of women's behaviors toward pregnancy. The results further show that frequent follow-up assessments of pregnancy planning behavior in large numbers of women are required to recruit an unbiased sample of preconception women. These findings will be useful to investigators designing prospective studies of fecundability, pregnancy outcomes and children's health. STUDY FUNDING/COMPETING INTERESTS: National Institutes of Health (contracts N01-HD53414, N01-HD63416, N01-HD53410, N01-HD53415, N01-HD53396, N01-HD53413 and N01-HD-53411; grant R21 ES016846) and by the University of California Irvine Center for Occupational and Environmental Health. No competing interests. TRIAL REGISTRATION NUMBER: None.
Asunto(s)
Encuestas de Prevalencia Anticonceptiva , Servicios de Planificación Familiar , Conducta Reproductiva , Adulto , Negro o Afroamericano , Asiático , Estudios de Cohortes , Servicios de Planificación Familiar/economía , Femenino , Hispánicos o Latinos , Humanos , Modelos Logísticos , Estudios Longitudinales , Estado Civil/etnología , Proyectos Piloto , Embarazo , Índice de Embarazo/etnología , Estudios Prospectivos , Conducta Reproductiva/etnología , Factores Socioeconómicos , Estados Unidos/epidemiología , Población BlancaRESUMEN
BACKGROUND: Over half of men who receive treatment for prostate suffer from a range of sexual problems that affect negatively their sexual health, sexual intimacy with their partners and their quality of life. In clinical practice, however, care for the sexual side effects of treatment is often suboptimal or unavailable. The goal of the current study is to test a web-based intervention to support the recovery of sexual intimacy of prostate cancer survivors and their partners after treatment. METHODS: The study team developed an interactive, web-based intervention, tailored to type of treatment received, relationship status (partnered/non-partnered) and sexual orientation. It consists of 10 modules, six follow the trajectory of the illness and four are theme based. They address sexual side effects, rehabilitation, psychological impacts and coaching for self-efficacy. Each includes a video to engage participants, psychoeducation and activities completed by participants on the web. Tailored strategies for identified concerns are sent by email after each module. Six of these modules will be tested in a randomized controlled trial and compared to usual care. Men with localized prostate cancer with partners will be recruited from five academic medical centers. These couples (N = 140) will be assessed prior to treatment, then 3 months and 6 months after treatment. The primary outcome will be the survivors' and partners' Global Satisfaction with Sex Life, assessed by a Patient Reported Outcome Measure Information Systems (PROMIS) measure. Secondary outcomes will include interest in sex, sexual activity, use of sexual aids, dyadic coping, knowledge about sexual recovery, grief about the loss of sexual function, and quality of life. The impact of the intervention on the couple will be assessed using the Actor-Partner Interaction Model, a mixed-effects linear regression model able to estimate both the association of partner characteristics with partner and patient outcomes and the association of patient characteristics with both outcomes. DISCUSSION: The web-based tool represents a novel approach to addressing the sexual health needs of prostate cancer survivors and their partners that-if found efficacious-will improve access to much needed specialty care in prostate cancer survivorship. TRIAL REGISTRATION: Clinicaltrials.gov registration # NCT02702453 , registered on March 3, 2016.
Asunto(s)
Neoplasias de la Próstata/epidemiología , Disfunciones Sexuales Fisiológicas/epidemiología , Disfunciones Sexuales Psicológicas/epidemiología , Estrés Psicológico , Adolescente , Adulto , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/fisiopatología , Neoplasias de la Próstata/psicología , Calidad de Vida , Conducta Sexual/fisiología , Conducta Sexual/psicología , Disfunciones Sexuales Fisiológicas/etiología , Disfunciones Sexuales Fisiológicas/fisiopatología , Disfunciones Sexuales Psicológicas/etiología , Disfunciones Sexuales Psicológicas/fisiopatología , Parejas Sexuales , Esposos/psicología , Adulto JovenRESUMEN
OBJECTIVE: To determine agreement on endometriosis diagnosis between real-time laparoscopy and subsequent expert review of digital images, operative reports, magnetic resonance imaging (MRI), and histopathology, viewed sequentially. DESIGN: Inter-rater agreement study. SETTING: Five urban surgical centres. POPULATION: Women, aged 18-44 years, who underwent a laparoscopy regardless of clinical indication. A random sample of 105 women with and 43 women without a postoperative endometriosis diagnosis was obtained from the ENDO study. METHODS: Laparoscopies were diagnosed, digitally recorded, and reassessed. MAIN OUTCOME MEASURES: Inter-observer agreement of endometriosis diagnosis and staging according to the revised American Society for Reproductive Medicine criteria. Prevalence and bias-adjusted kappa values (κ) were calculated for diagnosis, and weighted κ values were calculated for staging. RESULTS: Surgeons and expert reviewers had substantial agreement on diagnosis and staging after viewing digital images (n = 148; mean κ = 0.67, range 0.61-0.69; mean κ = 0.64, range 0.53-0.78, respectively) and after additionally viewing operative reports (n = 148; mean κ = 0.88, range 0.85-0.89; mean κ = 0.85, range 0.84-0.86, respectively). Although additionally viewing MRI findings (n = 36) did not greatly impact agreement, agreement substantially decreased after viewing histological findings (n = 67), with expert reviewers changing their assessment from a positive to a negative diagnosis in up to 20% of cases. CONCLUSION: Although these findings suggest that misclassification bias in the diagnosis or staging of endometriosis via visualised disease is minimal, they should alert gynaecologists who review operative images in order to make decisions on endometriosis treatment that operative reports/drawings and histopathology, but not necessarily MRI, will improve their ability to make sound judgments. TWEETABLE ABSTRACT: Endometriosis diagnosis and staging agreement between expert reviewers and operating surgeons was substantial.
Asunto(s)
Endometriosis/diagnóstico , Laparoscopía/estadística & datos numéricos , Adolescente , Adulto , Femenino , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
OBJECTIVE: To investigate perinatal outcomes associated with fertility treatments, including assisted reproductive technology (ART), intrauterine insemination with ovulation stimulation (IUI), and ovulation stimulation alone (OS). DESIGN: Population-representative cross-sectional survey of women with live births, 2004-2008. SETTING: Florida, Maryland, and Utah, USA. SAMPLE: 21 803 women, weighted to represent 1 022 597 women. METHODS: Survey and birth certificate data were analysed with logistic regression models adjusted for age, education, race, income, and parity, using separate models for singletons and all births. We used two referent groups: (1) women who never used fertility treatment and (2) subfertile women conceiving without treatment. MAIN OUTCOME MEASURES: Preterm birth (<37 weeks), very preterm birth (<34 weeks), low birthweight (<2500 g), and very low birthweight (<1500 g). RESULTS: Referent group 1: In singletons, ART was associated with preterm birth (OR 3.28; 95% CI 1.74, 6.20) and low birthweight (OR 2.91; 95% CI 1.99, 4.26). OS was also associated with low birthweight (OR 1.62; 95% CI 1.19, 2.19). Including all births, treatment was associated with preterm birth and low birthweight: ART (OR 6.21; 95% CI 4.21, 9.16 and OR 6.51; 95% CI 4.85, 8.73); IUI (OR 2.10; 95% CI 1.24, 3.56 and OR 2.41; 95% CI 1.54, 3.76); OS (OR 1.40; 95% CI 1.01, 1.94 and OR 2.10; 95% CI 1.60, 2.75), respectively. Referent group 2: ART was associated with both outcomes in all births, but not singletons. CONCLUSIONS: Preterm birth and low birthweight associated with fertility treatments are largely attributable to multiple gestation, but are also related to underlying subfertility. TWEETABLE ABSTRACT: Preterm birth is associated with subfertility, and with fertility treatments through multiple gestation.
Asunto(s)
Recién Nacido de Bajo Peso , Nacimiento Prematuro/etiología , Técnicas Reproductivas Asistidas/efectos adversos , Adulto , Estudios Transversales , Femenino , Florida , Humanos , Recién Nacido , Infertilidad/terapia , Tiempo de Internación/estadística & datos numéricos , Modelos Logísticos , Maryland , Embarazo , Resultado del Embarazo , Factores de Riesgo , UtahRESUMEN
BACKGROUND: Interaction between maternal obesity, intrauterine environment and adverse clinical outcomes of newborns has been described. METHODS: Using statewide birth certificate data, this retrospective, matched-control cohort study compared paired birth weights and complications of infants born to women before and after Roux-en-Y gastric bypass surgery (RYGB) and to matched obese non-operated women in several different groups. Women who had given birth to a child before and after RYGB (group 1; n=295 matches) and women with pregnancies after RYGB (group 2; n=764 matches) were matched to non-operated women based on age, body mass index (BMI) prior to both pregnancy and RYGB, mother's race, year of mother/s birth, date of infant births and birth order. In addition, birth weights of 13 143 live births before and/or after RYGB of their mothers (n=5819) were compared (group 3). RESULTS: Odds ratios (ORs) for having a large-for-gestational-age (LGA) neonate were significantly less after RYGB than for non-surgical mothers: ORs for groups 1 and 2 were 0.19 (0.08-0.38) and 0.33 (0.21-0.51), respectively. In contrast, ORs in all three groups for risk of having a small for gestational age (SGA) neonate were greater for RYGB mothers compared to non-surgical mothers (ORs were 2.16 (1.00-5.04); 2.16 (1.43-3.32); and 2.25 (1.89-2.69), respectively). Neonatal complications were not different for group 1 RYGB and non-surgical women for the first pregnancy following RYGB. Pregnancy-induced hypertension and gestational diabetes were significantly lower for the first pregnancy of mothers following RYGB compared to matched pregnancies of non-surgical mothers. CONCLUSION: Women who had undergone RYGB not only had lower risk for having an LGA neonate compared to BMI-matched mothers, but also had significantly higher risk for delivering an SGA neonate following RYGB. RYGB women were less likely than non-operated women to have pregnancy-related hypertension and diabetes.
Asunto(s)
Derivación Gástrica , Madres , Obesidad Mórbida/cirugía , Complicaciones del Embarazo/prevención & control , Adulto , Peso al Nacer , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Obesidad Mórbida/epidemiología , Obesidad Mórbida/metabolismo , Oportunidad Relativa , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/metabolismo , Resultado del Embarazo , Estudios Retrospectivos , Estados Unidos/epidemiologíaRESUMEN
STUDY QUESTION: What are the pain characteristics among women, with no prior endometriosis diagnosis, undergoing laparoscopy or laparotomy regardless of clinical indication? SUMMARY ANSWER: Women with surgically visualized endometriosis reported the highest chronic/cyclic pain and significantly greater dyspareunia, dysmenorrhea, and dyschezia compared with women with other gynecologic pathology (including uterine fibroids, pelvic adhesions, benign ovarian cysts, neoplasms and congenital Müllerian anomalies) or a normal pelvis. WHAT IS KNOWN ALREADY: Prior research has shown that various treatments for pain associated with endometriosis can be effective, making identification of specific pain characteristics in relation to endometriosis necessary for informing disease diagnosis and management. STUDY DESIGN, SIZE, DURATION: The study population for these analyses includes the ENDO Study (2007-2009) operative cohort: 473 women, ages 18-44 years, who underwent a diagnostic and/or therapeutic laparoscopy or laparotomy at one of 14 surgical centers located in Salt Lake City, UT or San Francisco, CA. Women with a history of surgically confirmed endometriosis were excluded. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Endometriosis was defined as surgically visualized disease; staging was based on revised American Society for Reproductive Medicine (rASRM) criteria. All women completed a computer-assisted personal interview at baseline specifying 17 types of pain (rating severity via 11-point visual analog scale) and identifying any of 35 perineal and 60 full-body front and 60 full-body back sites for which they experienced pain in the last 6 months. MAIN RESULTS AND THE ROLE OF CHANCE: There was a high prevalence (≥30%) of chronic and cyclic pelvic pain reported by the entire study cohort regardless of post-operative diagnosis. However, women with a post-operative endometriosis diagnosis, compared with women diagnosed with other gynecologic disorders or a normal pelvis, reported more cyclic pelvic pain (49.5% versus 31.0% and 33.1%, P < 0.001). Additionally, women with endometriosis compared with women with a normal pelvis experienced more chronic pain (44.2 versus 30.2%, P = 0.04). Deep pain with intercourse, cramping with periods, and pain with bowel elimination were much more likely reported in women with versus without endometriosis (all P < 0.002). A higher percentage of women diagnosed with endometriosis compared with women with a normal pelvis reported vaginal (22.6 versus 10.3%, P < 0.01), right labial (18.4 versus 8.1%, P < 0.05) and left labial pain (15.3 versus 3.7%, P < 0.01) along with pain in the right/left hypogastric and umbilical abdominopelvic regions (P < 0.05 for all). Among women with endometriosis, no clear and consistent patterns emerged regarding pain characteristics and endometriosis staging or anatomic location. LIMITATIONS, REASONS FOR CAUTION: Interpretation of our findings requires caution given that we were limited in our assessment of pain characteristics by endometriosis staging and anatomic location due to the majority of women having minimal (stage I) disease (56%) and lesions in peritoneum-only location (51%). Significance tests for pain topology related to gynecologic pathology were not corrected for multiple comparisons. WIDER IMPLICATIONS OF THE FINDINGS: Results of our research suggest that while women with endometriosis appear to have higher pelvic pain, particularly dyspareunia, dysmenorrhea, dyschezia and pain in the vaginal and abdominopelvic area than women with other gynecologic disorders or a normal pelvis, pelvic pain is commonly reported among women undergoing laparoscopy, even among women with no identified gynecologic pathology. Future research should explore causes of pelvic pain among women who seek out gynecologic care but with no apparent gynecologic pathology. Given our and other's research showing little correlation between pelvic pain and rASRM staging among women with endometriosis, further development and use of a classification system that can better predict outcomes for endometriosis patients with pelvic pain for both surgical and nonsurgical treatment is needed. STUDY FUNDING/COMPETING INTERESTS: Supported by the Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development (contracts NO1-DK-6-3428, NO1-DK-6-3427, and 10001406-02). The authors have no potential competing interests.
Asunto(s)
Endometriosis/diagnóstico , Laparoscopía , Laparotomía , Dolor/diagnóstico , Dolor Pélvico/etiología , Adolescente , Adulto , Estudios de Cohortes , Estreñimiento/diagnóstico , Dismenorrea/diagnóstico , Dispareunia/diagnóstico , Endometriosis/complicaciones , Endometriosis/epidemiología , Femenino , Humanos , Incidencia , Leiomioma/diagnóstico , Leiomioma/patología , Quistes Ováricos/diagnóstico , Quistes Ováricos/patología , Manejo del Dolor , Dimensión del Dolor , Dolor Pélvico/diagnóstico , Peritoneo/patología , Prevalencia , Adherencias Tisulares/diagnóstico , Adulto JovenRESUMEN
This study explored the relationship between riverine physical complexity, as determined from remotely sensed metrics, and anadromy and genetic diversity in steelhead or rainbow trout Oncorhynchus mykiss. The proportion of anadromy (estimated fraction of individuals within a drainage that are anadromous) was correlated with riverine complexity, but this correlation appeared to be driven largely by a confounding negative relationship between drainage area and the proportion of anadromy. Genetic diversity decreased with latitude, was lower in rivers with only non-anadromous individuals and also decreased with an increasing ratio of floodplain area to total drainage area. Anadromy may be less frequent in larger drainages due to the higher cost of migration associated with reaches farther from the ocean, and the negative relationship between genetic diversity and floodplain area may be due to lower effective population size resulting from greater population fluctuations associated with higher rates of habitat turnover. Ultimately, the relationships between riverine physical complexity and migratory life history or genetic diversity probably depend on the spatial scale of analysis.
Asunto(s)
Migración Animal , Ecosistema , Variación Genética , Oncorhynchus mykiss/genética , Animales , Frecuencia de los Genes , Genética de Población , Repeticiones de Microsatélite , Oncorhynchus mykiss/fisiología , Ríos , Análisis de Secuencia de ADNRESUMEN
OBJECTIVE: To describe risk factors for recurrent preterm birth (PTB) in the second and third birth. DESIGN: Historical cohort study. SETTING: Utah, USA. POPULATION: Women who had their first three singleton live births in Utah between 1989 and 2007 and a preterm first or second birth were included. METHODS: Maternally linked birth records were used. Multivariable-adjusted risk ratios were calculated for recurrent PTB. Results were stratified by spontaneous and indicated PTB and by pattern of birth outcomes. MAIN OUTCOME MEASURES: Risk ratios and 95% confidence intervals for risk factors for recurrent PTB. RESULTS: Among women with PTB in their first or second live birth, recurrent PTB occurred in 21% of second live births (n = 1011/4805) and 22% of third live births (n = 1872/8468). Risk factors for recurrence included short inter-pregnancy interval, underweight prepregnancy body mass index, pre-existing maternal medical conditions, history of PTB at 28-32 weeks of gestation (versus 33-36 weeks), the presence of a fetal anomaly, and young maternal age. Risk factors for spontaneous, but not indicated PTB included young maternal age and less than appropriate gestational weight gain. Risk factors also varied in women experiencing a first versus second recurrence in their third birth. CONCLUSIONS: Risk factors may vary by the clinical subtype of the most recent PTB and the pattern of term and preterm outcomes across births 1-3; some of the risk factors identified in this study may be modifiable through interventions targeted at women in the inter-conception period.
Asunto(s)
Paridad , Nacimiento Prematuro/etiología , Adulto , Certificado de Nacimiento , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Humanos , Análisis Multivariante , Embarazo , Recurrencia , Análisis de Regresión , Factores de Riesgo , UtahRESUMEN
PURPOSE: To evaluate the efficacy and safety of first-line, single-agent trastuzumab in women with HER2-overexpressing metastatic breast cancer. PATIENTS AND METHODS: One hundred fourteen women with HER2-overexpressing metastatic breast cancer were randomized to receive first-line treatment with trastuzumab 4 mg/kg loading dose, followed by 2 mg/kg weekly, or a higher 8 mg/kg loading dose, followed by 4 mg/kg weekly. RESULTS: The objective response rate was 26% (95% confidence interval [CI], 18.2% to 34.4%), with seven complete and 23 partial responses. Response rates in 111 assessable patients with 3+ and 2+ HER2 overexpression by immunohistochemistry (IHC) were 35% (95% CI, 24.4% to 44.7%) and none (95% CI, 0% to 15.5%), respectively. The clinical benefit rates in assessable patients with 3+ and 2+ HER2 overexpression were 48% and 7%, respectively. The response rates in 108 assessable patients with and without HER2 gene amplification by fluorescence in situ hybridization (FISH) analysis were 34% (95% CI, 23.9% to 45.7%) and 7% (95% CI, 0.8% to 22.8%), respectively. Seventeen (57%) of 30 patients with an objective response and 22 (51%) of 43 patients with clinical benefit had not experienced disease progression at follow-up at 12 months or later. The most common treatment-related adverse events were chills (25% of patients), asthenia (23%), fever (22%), pain (18%), and nausea (14%). Cardiac dysfunction occurred in two patients (2%); both had histories of cardiac disease and did not require additional intervention after discontinuation of trastuzumab. There was no clear evidence of a dose-response relationship for response, survival, or adverse events. CONCLUSION: Single-agent trastuzumab is active and well tolerated as first-line treatment of women with metastatic breast cancer with HER2 3+ overexpression by IHC or gene amplification by FISH.
RESUMEN
STUDY QUESTION: Does sexual intercourse enhance the cycle fecundability in women without known subfertility? SUMMARY ANSWER: Sexual intercourse (regardless of timing during the cycle) was associated with cycle characteristics suggesting higher fecundability, including longer luteal phase, less premenstrual spotting and more than 2 days of cervical fluid with estrogen-stimulated qualities. WHAT IS KNOWN ALREADY: Human females are spontaneous ovulators, experiencing an LH surge and ovulation cyclically, independent of copulation. Natural conception requires intercourse to occur during the fertile window of a woman's menstrual cycle, i.e. the 6-day interval ending on the day of ovulation. However, most women with normal fecundity do not ovulate on Day 14, thus the timing of the hypothetical fertile window varies within and between women. This variability is influenced by age and parity and other known or unknown elements. While the impact of sexual intercourse around the time of implantation on the probability of achieving a pregnancy has been discussed by some researchers, there are limited data regarding how sexual intercourse may influence ovulation occurrence and menstrual cycle characteristics in humans. STUDY DESIGN SIZE DURATION: This study is a pooled analysis of three cohorts of women, enrolled at Creighton Model FertilityCare centers in the USA and Canada: 'Creighton Model MultiCenter Fecundability Study' (CMFS: retrospective cohort, 1990-1996), 'Time to Pregnancy in Normal Fertility' (TTP: randomized trial, 2003-2006) and 'Creighton Model Effectiveness, Intentions, and Behaviors Assessment' (CEIBA: prospective cohort, 2009-2013). We evaluated cycle phase lengths, bleeding and cervical mucus patterns and estimated the fertile window in 2564 cycles of 530 women, followed for up to 1 year. PARTICIPANTS/MATERIALS SETTING METHODS: Participants were US or Canadian women aged 18-40 and not pregnant, who were heterosexually active, without known subfertility and not taking exogenous hormones. Most of the women were intending to avoid pregnancy at the start of follow-up. Women recorded daily vaginal bleeding, mucus discharge and sexual intercourse using a standardized protocol and recording system for up to 1 year, yielding 2564 cycles available for analysis. The peak day of mucus discharge (generally the last day of cervical fluid with estrogen-stimulated qualities of being clear, stretchy or slippery) was used to identify the estimated day of ovulation, which we considered the last day of the follicular phase in ovulatory cycles. We used linear mixed models to assess continuous cycle parameters including cycle, menses and cycle phase lengths, and generalized linear models using Poisson regression with robust variance to assess dichotomous outcomes such as ovulatory function, short luteal phases and presence or absence of follicular or luteal bleeding. Cycles were stratified by the presence or absence of any sexual intercourse, while adjusting for women's parity, age, recent oral contraceptive use and breast feeding. MAIN RESULTS AND THE ROLE OF CHANCE: Most women were <30 years of age (75.5%; median 27, interquartile range 24-29), non-Hispanic white (88.1%), with high socioeconomic indicators and nulliparous (70.9%). Cycles with no sexual intercourse compared to cycles with at least 1 day of sexual intercourse were shorter (29.1 days (95% CI 27.6, 30.7) versus 30.1 days (95% CI 28.7, 31.4)), had shorter luteal phases (10.8 days (95% CI 10.2, 11.5) versus 11.4 days (95% CI 10.9, 12.0)), had a higher probability of luteal phase deficiency (<10 days; adjusted probability ratio (PR) 1.31 (95% CI 1.00, 1.71)), had a higher probability of 2 days of premenstrual spotting (adjusted PR 2.15 (95% CI 1.09, 4.24)) and a higher probability of having two or fewer days of peak-type (estrogenic) cervical fluid (adjusted PR 1.49 (95% CI 1.03, 2.15)). LIMITATIONS REASONS FOR CAUTION: Our study participants were geographically dispersed but relatively homogeneous in regard to race, ethnicity, income and educational levels, and all had male partners, which may limit the generalizability of the findings. We cannot exclude the possibility of undetected subfertility or related gynecologic disorders among some of the women, such as undetected endometriosis or polycystic ovary syndrome, which would impact the generalizability of our findings. Acute illness or stressful events might have reduced the likelihood of any intercourse during a cycle, while also altering cycle characteristics. Some cycles in the no intercourse group may have actually had undocumented intercourse or other sexual activity, but this would bias our results toward the null. The Creighton Model FertilityCare System (CrM) discourages use of barrier methods, so we believe that most instances of intercourse involved exposure to semen; however, condoms may have been used in some cycles. Our dataset lacks any information about the occurrence of female orgasm, precluding our ability to evaluate the independent or combined impact of female orgasm on cycle characteristics. WIDER IMPLICATIONS OF THE FINDINGS: Sexual activity may change reproductive hormonal patterns, and/or levels of reproductive hormones may influence the likelihood of sexual activity. Future work may help with understanding the extent to which exposure to seminal fluid, and/or female orgasm and/or timing of intercourse could impact menstrual cycle function. In theory, large data sets from women using menstrual and fertility tracking apps could be informative if women can be appropriately incentivized to record intercourse completely. It is also of interest to understand how cycle characteristics may differ in women with gynecological problems or subfertility. STUDY FUNDING/COMPETING INTERESTS: Funding for the research on the three cohorts analyzed in this study was provided by the Robert Wood Johnson Foundation #029258 (Creighton Model MultiCenter Fecundability Study), the Eunice Kennedy Shriver National Institute of Child Health and Human Development 1K23 HD0147901-01A1 (Time to Pregnancy in Normal Fertility) and the Office of Family Planning, Office of Population Affairs, Health and Human Services 1FPRPA006035 (Creighton Model Effectiveness, Intentions, and Behaviors Assessment). The authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.
RESUMEN
INTRODUCTION: Response to trastuzumab in metastatic breast cancer correlates with expression of the high binding variant (158V) of the activating Fcγ receptor IIIA (CD16A). We engineered MGAH22, a chimeric anti-HER2 monoclonal antibody with specificity and affinity similar to trastuzumab, with an Fc domain engineered for increased binding to both alleles of human CD16A. METHODS: MGAH22 was compared to an identical anti-HER2 mAb except for a wild type Fc domain. Antibody-dependent cell cytotoxicity (ADCC) assays were performed with HER2-expressing cancer cells as targets and human PBMC or purified NK cells as effectors. Xenograft studies were conducted in mice with wild type murine FcγRs; in mice lacking murine CD16; or in mice lacking murine CD16 but transgenic for human CD16A-158F, the low-binding variant. The latter model reproduces the differential binding between wild type and the Fc-optimized mAb for human CD16A. The JIMT-1 human breast tumor line, derived from a patient that progressed on trastuzumab therapy, was used in these studies. Single and repeat dose toxicology studies with MGAH22 administered intravenously at high dose were conducted in cynomolgus monkeys. RESULTS: The optimized Fc domain confers enhanced ADCC against all HER2-positive tumor cells tested, including cells resistant to trastuzumab's anti-proliferative activity or expressing low HER2 levels. The greatest improvement occurs with effector cells isolated from donors homozygous or heterozygous for CD16A-158F, the low-binding allele. MGAH22 demonstrates increased activity against HER2-expressing tumors in mice transgenic for human CD16A-158F. In single and repeat-dose toxicology studies in cynomolgus monkeys, a species with a HER2 expression pattern comparable to that in humans and Fcγ receptors that exhibit enhanced binding to the optimized Fc domain, MGAH22 was well tolerated at all doses tested (15-150 mg/kg) and exhibited pharmacokinetic parameters similar to that of other anti-HER2 antibodies. Induction of cytokine release by MGAH22 in vivo or in vitro was similar to that induced by the corresponding wild type mAb or trastuzumab. CONCLUSIONS: The data support the clinical development of MGAH22, which may have utility in patients with low HER2 expressing tumors or carrying the CD16A low-binding allele.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Receptores de IgG/metabolismo , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/toxicidad , Anticuerpos Monoclonales Humanizados/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos , Antineoplásicos/metabolismo , Antineoplásicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Neoplasias/metabolismo , Unión Proteica , Receptor ErbB-2/inmunología , Receptor ErbB-2/metabolismo , TrastuzumabRESUMEN
BACKGROUND: The utility of procalcitonin testing in the pediatric intensive care unit (PICU) is not known. We sought to determine the impact of a procalcitonin-guided antibiotic treatment algorithm implemented with antibiotic stewardship (AS) guidance vs. usual care on antibiotic use in critically ill children. METHODS: Single center, pragmatic, randomized prospective clinical trial of critically ill children admitted to an ICU setting and started on intravenous antibiotics from February 15, 2018, to April 11, 2019. Patients were assigned on a monthly basis to either the procalcitonin or usual care arm. The procalcitonin arm had procalcitonin testing on hospital days 0, 1, 2, and 4 and stewardship assistance with algorithm result interpretation. Both arms had routine AS audit and feedback. The primary outcome was median antibiotic days of therapy per patient in the first 14-days after enrollment. RESULTS: Among 270 patients, 137 were in the procalcitonin arm and 133 in the usual care arm. Antibiotic days of therapy (DOT) were not significantly different between the procalcitonin arm (6.6, IQR: 3.1-10.9) and the usual care arm (7.6, IQR: 3-11.8; P = 0.37). More AS recommendations were made in the procalcitonin vs. control arm (54 vs. 37; P = 0.03). Adherence with algorithm-based antibiotic recommendations was high in the procalcitonin arm (70%). CONCLUSIONS: We found no difference in antibiotic DOT between study arms. This trial was underpowered but demonstrates feasibility of using a procalcitonin-guided antibiotic treatment algorithm with AS audit and feedback in the PICU.
Asunto(s)
Algoritmos , Antibacterianos/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos/métodos , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Polipéptido alfa Relacionado con Calcitonina/sangre , Programas de Optimización del Uso de los Antimicrobianos/normas , Programas de Optimización del Uso de los Antimicrobianos/estadística & datos numéricos , Biomarcadores , Preescolar , Estudios de Cohortes , Enfermedad Crítica , Femenino , Hospitalización , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Sepsis/tratamiento farmacológico , Sepsis/mortalidadRESUMEN
Collections of stream organisms from a domestic water supply system adjacent to the Tobacco River revealed that a detritus-based community exists in subterranean waters circulating through floodplain gravels at least 4.2 meters below and 50 meters laterally from the river channel. Several stone fly species spend their entire nymphal life cycles in underground habitats of the Flathead and Tobacco rivers.
RESUMEN
Based on a unifying theory presented here, it is predicted that the immune defects resulting in chronic inflammation rather than effective immune responses could be rectified by the therapeutic use of agents prepared from micro-organisms. With appropriate molecular patterns, these should be able to induce protective immunoregulatory networks or to reprogramme defective ones. In contrast to acute inflammation, chronic inflammation appears to have no beneficial role, but is a state of sustained immune reactivity in the presence or progression of a disease process. This results in an escalating cycle of tissue damage followed by unproductive tissue repair, breaks in self-tolerance, malignant transformation or deleterious changes in tissue morphology and function. Such inappropriate immune reactivity is an underlying characteristic, either in initiation or maintenance, of a diverse range of disease states including chronic infection, autoimmunity, allergy, cancer, vascular disease and metabolic alterations. Evidence is presented that the inappropriate immune reactivity is due, at least to some extent, to failures in the establishment of immunoregulatory networks as a result of hygiene-related factors. Such networks are the result of activation of antigen-presenting cells, principally dendritic cells, by molecular patterns of micro-organisms encountered sequentially during life and establishing the 'biography' of the immune system.
Asunto(s)
Productos Biológicos/uso terapéutico , Inflamación/inmunología , Animales , Autoinmunidad/inmunología , Productos Biológicos/inmunología , Enfermedad Crónica , Células Dendríticas/inmunología , Progresión de la Enfermedad , Humanos , Infecciones/inmunología , Infecciones/terapia , Inflamación/terapiaRESUMEN
INTRODUCTION: Agreement between available procalcitonin (PCT) assays is unclear. We sought to compare concordance between Roche and bioMérieux PCT assays using pediatric samples. METHODS: We evaluated 213 plasma samples from 208 children. We tested each sample on both the Roche and bioMérieux PCT platforms. RESULTS: At ranges < 2 µg/L, the Roche platform had a mean negative bias of 0.13 µg/L versus the bioMérieux platform. This bias resulted in PCT levels that crossed accepted cut points in 12.7% of patients. CONCLUSIONS: PCT levels measured on either platform are similar, especially at PCT ranges used for antibiotic decision-making algorithms. FUNDING: This work was supported by an investigator-initiated research agreement through bioMérieux and by the National Institute of Allergy and Infectious Diseases Childhood Infection Research Program (ChIRP), National Institute of Health and the National Center for Advancing Translational Sciences of the National Institute of Health.