610 research outputs found
Costing Framework for International Health Regulations (2005)
Costs can be estimated by identifying functional pathways toward achieving all 8 core capacities and global indicators
Restraint-induced Corticosterone Secretion and Hypothalamic CRH mRNA Expression are Augmented During Acute Withdrawal from Chronic Cocaine Administration
Stress responses during cocaine withdrawal likely contribute to drug relapse and may be intensified as a consequence of prior cocaine use. The present study examined changes in stressor-induced activation of the hypothalamic–pituitary–adrenal (HPA) axis during acute withdrawal from chronic cocaine administration. Adult male Sprague–Dawley rats received daily administration of cocaine (30 mg/kg, i.p.) or saline for 14 days. Twenty-four hours after the last injection, rats in each group were sacrificed under stress-free conditions or following 30 min of immobilization. Plasma corticosterone (CORT) was measured in trunk-blood using radioimmunoassay, corticotropin-releasing hormone (CRH) mRNA levels in the paraventricularnucleus (PVN) of the hypothalamus were measured using in situ hybridization and glucocorticoid receptor (GR) protein expression in the pituitary gland and dissected brain regions was measured using Western blot analysis. Basal CRH mRNA in the PVN was unaltered as a result of prior cocaine administration. However, a significant increase in CRH mRNA was observed 90 min following the termination of restraint in cocaine withdrawn, but not saline-treated, rats. Basal CORT was also unaffected by prior cocaine administration, but the CORT response measured immediately after restraint was significantly augmented in cocaine-withdrawn rats. Differences in GR protein expression in number of regions implicated in negative feedback regulation of HPA function, including the hypothalamus, were not observed. These findings indicate that the HPA response to stressors is intensified during early withdrawal from cocaine administration and may be independent of changes in GR-mediated negative feedback
Tracking the Orbital and Super-orbital Periods of SMC X-1
The High Mass X-ray Binary (HMXB) SMC X-1 demonstrates an orbital variation
of 3.89 days and a super-orbital variation with an average length of 55 days.
As we show here, however, the length of the super-orbital cycle varies by
almost a factor of two, even across adjacent cycles. To study both the orbital
and super-orbital variation we utilize lightcurves from the Rossi X-ray Timing
Explorer All Sky Monitor (RXTE-ASM). We employ the orbital ephemeris from
Wojdowski et al. (1998) to obtain the average orbital profile, and we show that
this profile exhibits complex modulation during non-eclipse phases.
Additionally, a very interesting ``bounceback'' in X-ray count rate is seen
during mid-orbital eclipse phases, with a softening of the emission during
these periods. This bounceback has not been previously identified in pointed
observations. We then define a super-orbital ephemeris (the phase of the
super-orbital cycle as a function of date) based on the ASM lightcurve and
analyze the trend and distribution of super-orbital cycle lengths. SMC X-1
exhibits a bimodal distribution of these lengths, similar to what has been
observed in other systems (e.g., Her X-1), but with more dramatic changes in
cycle length. There is some hint, but not conclusive evidence, for a dependence
of the super-orbital cycle length upon the underlying orbital period, as has
been observed previously for Her X-1 and Cyg X-2. Using our super-orbital
ephemeris we are also able to create an average super-orbital profile over the
71 observed cycles, for which we witness overall hardening of the spectrum
during low count rate times. We combine the orbital and super-orbital
ephemerides to study the correlation between the orbital and super-orbital
variations in the system.Comment: 10 pages, using emulateapj style. To be published in the
Astrophysical Journa
Implementation of the International Health Regulations (2005) through cooperative bioengagement
Cooperative bioengagement efforts, as practiced by U.S. government-funded entities, such as the Defense Threat Reduction Agency’s Cooperative Biological Engagement Program, the State Department’s Biosecurity Engagement Program, and parallel programs in other countries, exist at the nexus between public health and security. These programs have an explicit emphasis on developing projects that address the priorities of the partner country as well as the donor. While the objectives of cooperative bioengagement programs focus on reducing the potential for accidental or intentional misuse and/or release of dangerous biological agents, many partner countries are interested in bioengagement as a means to improve basic public health capacities. This article examines the extent to which cooperative bioengagement projects address public health capacity building under the revised International Health Regulations and alignment with the Global Health Security Agenda action packages
Few-Mode Fiber Coupled Superconducting Nanowire Single-Photon Detectors for Photon Efficient Optical Communications
The NASA Glenn Research Center's development of a high-photon efficiency real-time optical communications ground receiver has added superconducting nanowire single-photon detectors (SNSPDs) coupled with few-mode fibers (FMF). High data rate space-to-ground optical communication links require enhanced ground receiver sensitivity to reduce spacecraft transmitter constraints, and therefore require highly efficient coupling from fiber to detector. In the presence of atmospheric turbulence the received optical wave front can be severely distorted introducing higher-order spatial mode components to the received signal. To reduce mode filtering and mismatch loss and the resulting degradations to detector coupling efficiency, we explore the use of few-mode fiber coupling to commercial single-pixel SNSPDs. Graded index 20-m few-mode fibers allow the commercial single pixel SNSPD's active area to couple with equal efficiency as single mode fibers. Here we determine detector characteristics such as count rate, detection efficiency, dark counts, and jitter, as well as detection efficiencies for higher-order fiber spatial modes. Additionally, we assess the laboratory performance of the detectors in an optical system which emulates future deep space optical communications links
Development, Implementation, and Assessment of a Genetics Curriculum Across Institutions
Objective Many residency programs offer limited exposure and minimal didactic time genetics, despite its frequent use in obstetrics and gynecology. The objective of this study was to develop, pilot, and assess a three-module women's health genetics curriculum for residents that was easily transferable between institutions. Methods An interactive three-module genetics curriculum covering basic principles, prenatal screening/diagnosis, and cancer genetics was developed. A pre- and posttests were used to assess improvement in knowledge. Subjective feedback was obtained to assess curricular satisfaction. The data were analyzed with descriptive statistics. Results The curriculum was administered at two institutions. Forty-eight residents attended ≥ 1 session. Twenty completed the pretest, and 23 completed the posttest. At the first institution, using audience response system, the percentage correct per question increased on 10/14 questions between pre- and posttests. All students felt the curriculum was useful and would strongly recommend to other residents. At the second institution, pre/posttests were distributed on paper. Mean scores significantly improved between pre- and posttests (p = 0.007). On the pretest, no residents scored > 70%. However, 8/13 scored > 70% on the posttest (p = 0.002). Instructors at both institutions described the curriculum as easy to use/implement. Conclusion This three-module workshop on women's health genetics was easily implemented across institutions and led to increased knowledge
Long-term culture of human breast cancer specimens and their analysis using optical projection tomography
Breast cancer is a leading cause of mortality in the Western world. It is well established that the spread of breast cancer, first locally and later distally, is a major factor in patient prognosis. Experimental systems of breast cancer rely on cell lines usually derived from primary tumours or pleural effusions. Two major obstacles hinder this research: (i) some known sub-types of breast cancers (notably poor prognosis luminal B tumours) are not represented within current line collections; (ii) the influence of the tumour microenvironment is not usually taken into account. We demonstrate a technique to culture primary breast cancer specimens of all sub-types. This is achieved by using three-dimensional (3D) culture system in which small pieces of tumour are embedded in soft rat collagen I cushions. Within 2-3 weeks, the tumour cells spread into the collagen and form various structures similar to those observed in human tumours1. Viable adipocytes, epithelial cells and fibroblasts within the original core were evident on histology. Malignant epithelial cells with squamoid morphology were demonstrated invading into the surrounding collagen. Nuclear pleomorphism was evident within these cells, along with mitotic figures and apoptotic bodies. We have employed Optical Projection Tomography (OPT), a 3D imaging technology, in order to quantify the extent of tumour spread in culture. We have used OPT to measure the bulk volume of the tumour culture, a parameter routinely measured during the neo-adjuvant treatment of breast cancer patients to assess response to drug therapy. Here, we present an opportunity to culture human breast tumours without sub-type bias and quantify the spread of those ex vivo. This method could be used in the future to quantify drug sensitivity in original tumour. This may provide a more predictive model than currently used cell lines.Publisher PDFPeer reviewe
Time From First Intercourse to First Sexually Transmitted Infection Diagnosis Among Adolescent Women
Objective To determine the time between first intercourse and first sexually transmitted infection (STI) with Chlamydia trachomatis, Neisseria gonorrhoeae, or Trichomonas vaginalis and time between repeated infections.
Design Observational study.
Setting Three adolescent medicine clinics.
Participants A cohort of 386 urban young women aged 14 to 17 years at enrollment.
Main Outcome Measures Age at first intercourse; organism-specific interval between first intercourse and first STI diagnosis; interval between repeated infections; and age at first STI test prior to study participation.
Results Participants had first intercourse at a young age (first, second, and third quartiles were 13, 14, and 15 years of age, respectively). By age 15 years, 25% of the women acquired their first STI, most often C trachomatis. Median interval between first intercourse and first STI diagnosis was 2 years. Within 1 year of first intercourse, 25% had their first C trachomatis infection. Repeated infections were common; within 3.6, 6, and 4.8 months, 25% of the women with prior C trachomatis, N gonorrhoeae, and T vaginalis infection were reinfected with the respective organisms. Considerable delay in STI testing was found for those who began sex at a younger age. The median interval between first sex and first test were 4.9, 3.5, 2.1, 1.8, and 1.2 years for those who had first sex at ages 10, 11, 12, 13, and 14 years, respectively.
Conclusions Timely screening and treatment are important for prevention of STI sequelae. For urban adolescent women, STI screening (especially for C trachomatis) should begin within a year after first intercourse and infected individuals should be retested every 3 to 4 months
Development and validation of a Spanish translation of the Yale activity questionnaire
Background: Valid measures of physical activity are critical research tools. The objective of this study was to develop a Spanish translation of the Yale Physical Activity Survey, and to provide preliminary evidence of its validity in a population of Dominican patients with lower extremity arthritis. Methods: A Dominican bilingual health care professional translated the Yale Physical Activity Survey (YPAS) from English to Spanish. Several Dominican adults reviewed the translation to ensure it was linguistically and culturally appropriate. The questionnaire was back-translated to English by a North American researcher who is fluent in Spanish. Discrepancies between the original and back-translated versions were resolved by the translator and back-translator. The Spanish translation was administered to 108 Dominican subjects with advanced hip or knee arthritis prior to (N = 44) or one to four years following (N = 64) total joint replacement. We assessed construct validity by examining the association of YPAS scores and measures of functional status and pain (WOMAC), quality of life (EQ-5D) and the number of painful lower extremity joints. Results: A higher YPAS Part II Activity Dimensions Summary Index score had weak to modest correlations with worse function and quality of life as measured with the WOMAC function scale (r = 0.21, p = 0.03), SF-36 Physical Activity Scale (r = 0.29, p = 0.004) and EQ-5D (r = 0.34, p = 0.0007). Total minutes of vigorous activity and walking had weak to modest correlation with these measures (WOMAC Function Scale (r = 0.15, p = 0.15), SF-36 Physical Activity Scale (r = 0.21, p = 0.04) and EQ-5D utility (r = 0.24, p = 0.02)). Correlations between the YPAS Part I energy expenditure score and these measures were lower (WOMAC Function Scale (r = 0.07, p = 0.49), SF-36 Physical Activity Scale (r = 0.03, p = 0.74) and EQ-5D utility (r = 0.18, p = 0.07)). Conclusions: We have developed a new Spanish translation of the Yale Physical Activity Survey and provided evidence of convergent validity in a sample of Dominican patients prior to or 1–4 years following total joint replacement
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