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31.
Hogge WA Byrnes AL Lanasa MC Surti U 《American journal of obstetrics and gynecology》2003,189(2):397-400; discussion 400-2
OBJECTIVE: The objective of this study was to assess the clinical use of routinely karyotyping spontaneous abortion material. STUDY DESIGN: We retrospectively reviewed the records of the Pittsburgh Cytogenetics Laboratory from January 1, 1998, to December 31, 2001, for all tissues from spontaneous losses at 20 weeks' gestation or less for which complete medical records were available. RESULTS: There were 517 submitted samples of which 28 (5.4%) failed to grow in culture. Overall, 55.8% of samples were abnormal; 52.3% of normal results were male. In samples from pregnancies at 13 weeks or less the rate of abnormality was 69.1%. When analyzed by maternal age, the rate of abnormality for first-trimester losses was 57.2% in women younger than 35 years, and 82.3% in those 35 years or older. There was no difference in the rate of abnormality when comparing first loss with two or more losses, first pregnancy with two or more pregnancies, or the presence or absence of at least one live birth. CONCLUSION: Chromosome abnormalities are the cause for pregnancy loss in 50% to 80% of cases, depending on maternal age and gestational age at time of the loss. Karyotyping of spontaneous losses in the first trimester beginning with the patient's second loss provides clinically important etiologic information and decreases the number of evaluations necessary for recurrent pregnancy loss. 相似文献
32.
Jan Willem van der Laan Robert E. Chapin Bert Haenen Abigail C. Jacobs Aldert Piersma 《Regulatory toxicology and pharmacology : RTP》2012
Reproductive toxicity testing is characterized by high animal use. For registration of pharmaceutical compounds, developmental toxicity studies are usually conducted in both rat and rabbits. Efforts have been underway for a long time to design alternatives to animal use. Implementation has lagged, partly because of uncertainties about the applicability domain of the alternatives. 相似文献
33.
Judy Strickland Qingda Zang Nicole Kleinstreuer Michael Paris David M. Lehmann Neepa Choksi Joanna Matheson Abigail Jacobs Anna Lowit David Allen Warren Casey 《Journal of applied toxicology : JAT》2016,36(9):1150-1162
One of the top priorities of the Interagency Coordinating Committee for the Validation of Alternative Methods (ICCVAM) is the identification and evaluation of non‐animal alternatives for skin sensitization testing. Although skin sensitization is a complex process, the key biological events of the process have been well characterized in an adverse outcome pathway (AOP) proposed by the Organisation for Economic Co‐operation and Development (OECD). Accordingly, ICCVAM is working to develop integrated decision strategies based on the AOP using in vitro, in chemico and in silico information. Data were compiled for 120 substances tested in the murine local lymph node assay (LLNA), direct peptide reactivity assay (DPRA), human cell line activation test (h‐CLAT) and KeratinoSens assay. Data for six physicochemical properties, which may affect skin penetration, were also collected, and skin sensitization read‐across predictions were performed using OECD QSAR Toolbox. All data were combined into a variety of potential integrated decision strategies to predict LLNA outcomes using a training set of 94 substances and an external test set of 26 substances. Fifty‐four models were built using multiple combinations of machine learning approaches and predictor variables. The seven models with the highest accuracy (89–96% for the test set and 96–99% for the training set) for predicting LLNA outcomes used a support vector machine (SVM) approach with different combinations of predictor variables. The performance statistics of the SVM models were higher than any of the non‐animal tests alone and higher than simple test battery approaches using these methods. These data suggest that computational approaches are promising tools to effectively integrate data sources to identify potential skin sensitizers without animal testing. Published 2016. This article has been contributed to by US Government employees and their work is in the public domain in the USA. 相似文献
34.
Introduction: The inhalation of substances, both medicinally and recreationally, is a commonly used method of drug administration but has been underutilized in the treatment of neurologic disorders such as migraine. Three drugs have been studied as potential inhalable treatments for acute migraine: dihydroergotamine (MAP0004), prochlorperazine (Staccato prochlorperazine), and loxapine (Staccato loxapine).Areas covered: This review discusses the available literature describing the pharmacokinetics, tolerability and efficacy of MAP0004, Staccato prochlorperazine and Staccato loxapine, including data from Phase II and Phase III clinical trials.Expert opinion: Inhaled DHE offers rapid absorption with a pharmacokinetic profile similar to IV administration. Improved side effect profile results from more selective binding at antimigraine serotonergic receptors 5-HT1B and 5-HT1D. Inhaled prochlorperazine is rapidly absorbed and resulted in statistically significant migraine pain relief at 2 hours compared to placebo but is not currently being pursued by the manufacturer as a potential migraine abortive. Inhaled loxapine is also rapidly absorbed into systemic circulation but Phase IIb trials did not show statistically improved pain relief or pain freedom compared to placebo. MAP0004 will likely provide a good alternative to patients seeking rapid relief without the need for injection or other invasive routes. 相似文献
35.
Bernstein K Baer A Pollack M Sebrow D Elstein D Ioscovich A 《Journal of perinatal medicine》2008,36(2):120-123
Regional anesthesia for pain at delivery in the presence of maternal thrombocytopenia is a clinical dilemma. We reviewed 10,369 obstetric cases (12 months) from our tertiary center. Generally, hemodilution of pregnancy does not result in thrombocyte counts of <150,000/mm(3) at delivery. A total of 166 births (1.6%) were recorded in women with thrombocytes <150,000/mm(3) at delivery. Parturients with >150,000/mm(3) at week 36 were separated post hoc (n=35; 21%) and the remaining parturients were divided as having <100,000/mm(3) (n=30; 18%) or 101,000-150,000/mm(3) (n=101; 60.5%). Epidural or spinal anesthesia was administered to 30% women with <100,000/mm(3) whereas 56% women with >101,000/mm(3) received these options (P=0.003). A total of 13.9% of parturients with trimester-long thrombocytopenia required blood products; 10/23 (43.5%) parturients undergoing cesarean section also required blood products (P=0.000). Four of six babies with Apgar scores of 相似文献
36.
Peled Y Yogev Y Kahn A Mashiach R Berant M Pardo J 《Archives of gynecology and obstetrics》2008,278(3):237-239
Objective Correct prenatal determination of the fetal right/left axis is essential for the diagnosis of fetal malformations, in particular
congenital heart anomalies. A reliable method of transabdominal echocardiographic assessment of the fetal situs in the late
second trimester was established. We aimed to determine the validity of the transvaginal approach to assess fetal axis.
Method The study group consisted of 108 consecutive women in the second trimester of a singleton pregnancy, undergoing elective transvaginal
anatomy scans. All had undergone previous transabdominal echocardiography to establish fetal axis. The same technique was
used to assess the fetal axis during the transvaginal study, and the findings were compared.
Results There was total agreement in fetal axis determination between transabdominal and transvaginal scans in all cases. The accuracy
of the transvaginal study was not affected by maternal obesity, fetal position or the presence of cardiac malformation (in
one case).
Conclusion Transvaginal ultrasonography is the reliable and accurate means of determining the fetal axis.
Both affiliations are affiliated with Sackler Faculty of Medicine, Tel Aviv
University. 相似文献
37.
Katherine M. McNitt Emily E. Hohman Daniel E. Rivera Penghong Guo Abigail M. Pauley Alison D. Gernand Danielle Symons Downs Jennifer S. Savage 《Nutrients》2022,14(11)
(1) Background: Energy intake (EI) underreporting is a widespread problem of great relevance to public health, yet is poorly described among pregnant women. This study aimed to describe and predict error in self-reported EI across pregnancy among women with overweight or obesity. (2) Methods: Participants were from the Healthy Mom Zone study, an adaptive intervention to regulate gestational weight gain (GWG) tested in a feasibility RCT and followed women (n = 21) with body mass index (BMI) ≥25 from 8–12 weeks to ~36 weeks gestation. Mobile health technology was used to measure daily weight (Wi-Fi Smart Scale), physical activity (activity monitor), and self-reported EI (MyFitnessPal App). Estimated EI was back-calculated daily from measured weight and physical activity data. Associations between underreporting and gestational age, demographics, pre-pregnancy BMI, GWG, perceived stress, and eating behaviors were tested. (3) Results: On average, women were 30.7 years old and primiparous (62%); reporting error was −38% ± 26 (range: −134% (underreporting) to 97% (overreporting)), representing an ~1134 kcal daily underestimation of EI (1404 observations). Estimated (back-calculated), but not self-reported, EI increased across gestation (p < 0.0001). Higher pre-pregnancy BMI (p = 0.01) and weekly GWG (p = 0.0007) was associated with greater underreporting. Underreporting was lower when participants reported higher stress (p = 0.02) and emotional eating (p < 0.0001) compared with their own average. (4) Conclusions: These findings suggest systemic underreporting in pregnant women with elevated BMI using a popular mobile app to monitor diet. Advances in technology that allow estimation of EI from weight and physical activity data may provide more accurate dietary self-monitoring during pregnancy. 相似文献
38.
Rachael N. Martinez Bridget M. Smith Dustin D. French Timothy P. Hogan Beverly Gonzalez Chad M. Osteen Maya Hatch Vicki Anderson Elizabeth Tarlov Abigail Silva Barry Goldstein Kevin T. Stroupe 《The journal of spinal cord medicine》2022,45(4):575
Context/Objective: Provisions of the Affordable Care Act (ACA) potentially increase insurance options for Veterans with disabilities. We examined Veterans with spinal cord injuries and disorders (SCI/D) to assess whether the ACA was associated with changes in healthcare utilization from Department of Veterans Affairs (VA) healthcare facilities.Design: Using national VA data, we investigated impacts on VA healthcare utilization pre- (2012/13) and post-ACA (2014/15) implementation with negative binomial regression models.Setting: VA healthcare facilities.Participants: 8,591 VA users with SCI/D. Veterans with acute myelitis, Guillain-Barré syndrome, multiple sclerosis, or amyotrophic lateral sclerosis were excluded as were patients who died during the study period.Interventions: We assessed VA healthcare utilization before and after ACA implementation.Outcome Measures: Total numbers of VA visits for SCI/D care, diagnostic care, primary care, specialty care, and mental health care, and VA admissions.Results: The number of VA admissions was 7% higher in the post than pre-ACA implementation period (P < 0.01). The number of VA visits post-implementation increased for SCI/D care (8%; P < 0.01) and specialty care (12%; P < 0.001). Conversely, the number of mental health visits was 17% lower in the post-ACA period (P < 0.001). Veterans with SCI/D who live <5 miles from their nearest VA facility received VA care more frequently than those ≥40 miles from VA (P < 0.001).Conclusion: Counter to expectations, results suggest that Veterans with SCI/D sought more frequent VA care after ACA implementation, indicating Veterans with SCI/D continue to utilize the lifelong, comprehensive care provided at VA. 相似文献
39.
Emily A. Smith Abigail L. Schwartz James B. Lucot 《Journal of pharmacological and toxicological methods》2013,67(1):45-49
IntroductionAnalysis of catecholamines in small samples of urine is difficult and sensitive to stress. Current techniques require pooling of samples or expensive separation by double mass spectrometry. A method for extraction of unconjugated catecholamines in 20 μL urine samples has been developed using alumina extraction prior to separation by high performance liquid chromatography (HPLC) and electrochemical detection (ECD).MethodsThree murine experiments tested the application of the procedure. In the first, collection occurred in the morning and evening prior to handling, and in the morning after three days of handling. In the second, passively obtained urine was compared to stressfully obtained urine in the same mice. Finally, basal collections were compared to urinary catecholamine levels 15 and 30 min into novel cage stress. Urine was extracted alongside 2,3-dihydroxybenzoic acid (DHBA) internal standard via alumina and brought to pH 8.5 with tris buffer. The mixture underwent two wash steps for depuration and eluted with perchloric acid for analysis on HPLC with ECD.ResultsThis novel extraction method using low amounts of urine yielded 48% recovery in the samples and 60% recovery in the standard extraction on average. With a signal to noise ratio of 3:1, the limit of detection (LOD) of a standard is 1.2 pg/mL, which allows for the detection of 3.6 pg/mL in urine or 72 fg in a 20 μL sample. Thus resting catecholamine levels are 216 times higher than the LOD. Unconjugated norepinephrine and epinephrine levels were significantly increased 15 min after novel cage stress and epinephrine remained elevated after 30 min, but did not show significant differences when comparing collection time, handling exposure, or specific collection technique.DiscussionThe technique is an effective measure for sympathetic activity in micro samples, with a limit of detection in the attomole range for 20 μL samples. 相似文献
40.
Abigail De La Pena Marah Mukhtar Ryosuke Yokosawa Santiago Carrasquilla Chelsey S. Simmons 《Experimental dermatology》2021,30(1):74-83
Traction force microscopy (TFM) is a well‐established technique traditionally used by biophysicists to quantify the forces adherent biological cells exert on their microenvironment. As image processing software becomes increasingly user‐friendly, TFM is being adopted by broader audiences to quantify contractility of (myo)fibroblasts. While many technical reviews of TFM’s computational mechanics are available, this review focuses on practical experimental considerations for dermatology researchers new to cell mechanics and TFM who may wish to implement a higher throughput and less expensive alternative to collagen compaction assays. Here, we describe implementation of experimental methods, analysis using open‐source software and troubleshooting of common issues to enable researchers to leverage TFM for their investigations into skin fibroblasts. 相似文献