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21.
AK Greenberg F Lu JD Goldberg E Eylers JC Tsay TA Yie D Naidich G McGuinness H Pass KM Tchou-Wong D Addrizzo-Harris A Chachoua B Crawford WN Rom 《PloS one》2012,7(7):e39403
Background
Low-dose computed tomography (CT) for lung cancer screening can reduce lung cancer mortality. The National Lung Screening Trial reported a 20% reduction in lung cancer mortality in high-risk smokers. However, CT scanning is extremely sensitive and detects non-calcified nodules (NCNs) in 24–50% of subjects, suggesting an unacceptably high false-positive rate. We hypothesized that by reviewing demographic, clinical and nodule characteristics, we could identify risk factors associated with the presence of nodules on screening CT, and with the probability that a NCN was malignant.Methods
We performed a longitudinal lung cancer biomarker discovery trial (NYU LCBC) that included low-dose CT-screening of high-risk individuals over 50 years of age, with more than 20 pack-year smoking histories, living in an urban setting, and with a potential for asbestos exposure. We used case-control studies to identify risk factors associated with the presence of nodules (n = 625) versus no nodules (n = 557), and lung cancer patients (n = 30) versus benign nodules (n = 128).Results
The NYU LCBC followed 1182 study subjects prospectively over a 10-year period. We found 52% to have NCNs >4 mm on their baseline screen. Most of the nodules were stable, and 9.7% of solid and 26.2% of sub-solid nodules resolved. We diagnosed 30 lung cancers, 26 stage I. Three patients had synchronous primary lung cancers or multifocal disease. Thus, there were 33 lung cancers: 10 incident, and 23 prevalent. A sub-group of the prevalent group were stable for a prolonged period prior to diagnosis. These were all stage I at diagnosis and 12/13 were adenocarcinomas.Conclusions
NCNs are common among CT-screened high-risk subjects and can often be managed conservatively. Risk factors for malignancy included increasing age, size and number of nodules, reduced FEV1 and FVC, and increased pack-years smoking. A sub-group of screen-detected cancers are slow-growing and may contribute to over-diagnosis and lead-time biases. 相似文献22.
Tara D. Wehrly Audrey Chong Kimmo Virtaneva Dan E. Sturdevant Robert Child Jessica A. Edwards Dedeke Brouwer Vinod Nair Elizabeth R. Fischer Luke Wicke Alissa J. Curda John J. Kupko III Craig Martens Deborah D. Crane Catharine M. Bosio Stephen F. Porcella Jean Celli 《Cellular microbiology》2009,11(7):1128-1150
23.
Ute Seeland Ahmad T. Nauman Alissa Cornelis Sabine Ludwig Mathias Dunkel Georgios Kararigas Vera Regitz-Zagrosek 《Biology of sex differences》2016,7(1):39
Background
Sex and Gender Medicine is a novel discipline that provides equitable medical care for society and improves outcomes for both male and female patients. The integration of sex- and gender-specific knowledge into medical curricula is limited due to adequate learning material, systematic teacher training and an innovative communication strategy. We aimed at initiating an e-learning and knowledge-sharing platform for Sex and Gender Medicine, the eGender platform (http://egender.charite.de), to ensure that future doctors and health professionals will have adequate knowledge and communication skills on sex and gender differences in order to make informed decisions for their patients.Methods
The web-based eGender knowledge-sharing platform was designed to support the blended learning pedagogical teaching concept and follows the didactic concept of constructivism. Learning materials developed by Sex and Gender Medicine experts of seven universities have been used as the basis for the new learning tools. The content of these tools is patient-centered and provides add-on information on gender-sensitive aspects of diseases. The structural part of eGender was designed and developed using the open source e-learning platform Moodle. The eGender platform comprises an English and a German version of e-learning modules: one focusing on basic knowledge and seven on specific medical disciplines. Each module consists of several courses corresponding to a disease or symptom complex. Self-organized learning has to be managed by using different learning tools, e.g., texts and audiovisual material, tools for online communication and collaborative work.Results
More than 90 users from Europe registered for the eGender Medicine learning modules. The most frequently accessed module was “Gender Medicine—Basics” and the users favored discussion forums. These e-learning modules fulfill the quality criteria for higher education and are used within the elective Master Module “Gender Medicine—Basics” implemented into the accredited Master of Public Health at Charité—Berlin.Conclusions
The eGender platform is a flexible and user-friendly electronical knowledge-sharing platform providing evidence-based high-quality learning material used by a growing number of registered users. The eGender Medicine learning modules could be key in the reform of medical curricula to integrate Sex and Gender Medicine into the education of health professionals.24.
Alissa J. Kamens Kaley M. Mientkiewicz Robyn J. Eisert Jenna A. Walz Charles R. Mace Joshua A. Kritzer 《Bioorganic & medicinal chemistry》2018,26(6):1206-1211
Recycling of receptors from the endosomal recycling compartment to the plasma membrane is a critical cellular process, and recycling is particularly important for maintaining invasiveness in solid tumors. In this work, we continue our efforts to inhibit EHD1, a critical adaptor protein involved in receptor recycling. We applied a diversity-oriented macrocyclization approach to produce cyclic peptides with varied conformations, but that each contain a motif that binds to the EH domain of EHD1. Screening these uncovered several new inhibitors for EHD1’s EH domain, the most potent of which bound with a Kd of 3.1 μM. Several of the most potent inhibitors were tested in a cellular assay that measures extent of vesicle recycling. Inhibiting EHD1 could potentially slow cancer invasiveness and metastasis, and these cyclic peptides represent the most potent inhibitors of EHD1 to date. 相似文献
25.
Sergey Ryzhov Bong Hwan Sung Qinkun Zhang Alissa Weaver Richard J. Gumina Italo Biaggioni Igor Feoktistov 《Purinergic signalling》2014,10(3):477-486
Adenosine levels increase in ischemic hearts and contribute to the modulation of that pathological environment. We previously showed that A2B adenosine receptors on mouse cardiac Sca1+CD31− mesenchymal stromal cells upregulate secretion of paracrine factors that may contribute to the improvement in cardiac recovery seen when these cells are transplanted in infarcted hearts. In this study, we tested the hypothesis that A2B receptor signaling regulates the transition of Sca1+CD31− cells, which occurs after myocardial injury, into a myofibroblast phenotype that promotes myocardial repair and remodeling. In vitro, TGFβ1 induced the expression of the myofibroblast marker α-smooth muscle actin (αSMA) and increased collagen I generation in Sca1+CD31− cells. Stimulation of A2B receptors attenuated TGFβ1-induced collagen I secretion but had no effect on αSMA expression. In vivo, myocardial infarction resulted in a rapid increase in the numbers of αSMA-positive cardiac stromal cells by day 5 followed by a gradual decline. Genetic deletion of A2B receptors had no effect on the initial accumulation of αSMA-expressing stromal cells but hastened their subsequent decline; the numbers of αSMA-positive cells including Sca1+CD31− cells remained significantly higher in wild type compared with A2B knockout hearts. Thus, our study revealed a significant contribution of cardiac Sca1+CD31− cells to the accumulation of αSMA-expressing cells after infarction and implicated A2B receptor signaling in regulation of myocardial repair and remodeling by delaying deactivation of these cells. It is plausible that this phenomenon may contribute to the beneficial effects of transplantation of these cells to the injured heart.
Electronic supplementary material
The online version of this article (doi:10.1007/s11302-014-9410-y) contains supplementary material, which is available to authorized users. 相似文献26.
Nonvisual arrestins are regulated by direct post-translational modifications, such as phosphorylation, ubiquitination, and nitrosylation. However, whether arrestins are regulated by other post-translational modifications remains unknown. Here we show that nonvisual arrestins are modified by small ubiquitin-like modifier 1 (SUMO-1) upon activation of β(2)-adrenergic receptor (β(2)AR). Lysine residues 295 and 400 in arrestin-3 fall within canonical SUMO consensus sites, and mutagenic analysis reveals that Lys-400 represents the main SUMOylation site. Depletion of the SUMO E2 modifying enzyme Ubc9 blocks arrestin-3 SUMOylation and attenuates β(2)AR internalization, suggesting that arrestin SUMOylation mediates G protein-coupled receptor endocytosis. Consistent with this, expression of a SUMO-deficient arrestin mutant failed to promote β(2)AR internalization as compared with wild-type arrestin-3. Our data reveal an unprecedented role for SUMOylation in mediating GPCR endocytosis and provide novel mechanistic insight into arrestin function and regulation. 相似文献
27.
This study conducts a life cycle assessment of a simulated dry mill corn ethanol facility in California’s Central Valley retrofitted to also produce ethanol from corn stover, a cellulosic feedstock. The assessment examines three facility designs, all producing corn ethanol and wet distiller’s grains and solubles as a co-product: a baseline facility with no cellulosic retrofit, a facility retrofitted with a small capacity for stover feedstock, and a facility retrofitted for a large capacity of stover feedstock. Corn grain is supplied by rail from the Midwest, while stover is sourced from in-state farms and delivered by truck. Two stover feedstock supply scenarios are considered, testing harvest rates at 25 or 40 % of stover mass. Allocation is required to separate impacts attributable to co-products. Additional scenarios are explored to assess the effect of co-product allocation methods on life cycle assessment results for the two fuel products, corn ethanol and stover ethanol. The assessment tracks greenhouse gas (GHG) emissions, energy consumption, criteria air pollutants, and direct water consumption. The GHG intensity of corn ethanol produced from the three facility designs range between 61.3 and 68.9 g CO2e/MJ, which includes 19.8 g CO2e/MJ from indirect land use change for Midwestern corn grain. The GHG intensity of cellulosic ethanol varies from 44.1 to 109.2 g CO2e/MJ, and 14.6 to 32.1 g CO2e/MJ in the low and high stover capacity cases, respectively. Total energy input ranges between 0.60 and 0.71 MJ/MJ for corn ethanol and 0.13 to 2.29 MJ/MJ for stover ethanol. This variability is the result of the stover supply scenarios (a function of harvest rate) and co-product allocation decisions. 相似文献
28.
Susan S. Brooks Alissa L. Wall Christelle Golzio David W. Reid Amalia Kondyles Jason R. Willer Christina Botti Christopher V. Nicchitta Nicholas Katsanis Erica E. Davis 《Genetics》2014,198(2):723-733
Neurodevelopmental defects in humans represent a clinically heterogeneous group of disorders. Here, we report the genetic and functional dissection of a multigenerational pedigree with an X-linked syndromic disorder hallmarked by microcephaly, growth retardation, and seizures. Using an X-linked intellectual disability (XLID) next-generation sequencing diagnostic panel, we identified a novel missense mutation in the gene encoding 60S ribosomal protein L10 (RPL10), a locus associated previously with autism spectrum disorders (ASD); the p.K78E change segregated with disease under an X-linked recessive paradigm while, consistent with causality, carrier females exhibited skewed X inactivation. To examine the functional consequences of the p.K78E change, we modeled RPL10 dysfunction in zebrafish. We show that endogenous rpl10 expression is augmented in anterior structures, and that suppression decreases head size in developing morphant embryos, concomitant with reduced bulk translation and increased apoptosis in the brain. Subsequently, using in vivo complementation, we demonstrate that p.K78E is a loss-of-function variant. Together, our findings suggest that a mutation within the conserved N-terminal end of RPL10, a protein in close proximity to the peptidyl transferase active site of the 60S ribosomal subunit, causes severe defects in brain formation and function. 相似文献
29.
Shiraz Badurdeen Peter G. Davis Stuart B. Hooper Susan Donath Georgia A. Santomartino Alissa Heng Diana Zannino Monsurul Hoq C. Omar F Kamlin Stefan C. Kane Anthony Woodward Calum T. Roberts Graeme R. Polglase Douglas A. Blank 《PLoS medicine》2022,19(6)
BackgroundGlobally, the majority of newborns requiring resuscitation at birth are full term or late-preterm infants. These infants typically have their umbilical cord clamped early (ECC) before moving to a resuscitation platform, losing the potential support of the placental circulation. Physiologically based cord clamping (PBCC) is clamping the umbilical cord after establishing lung aeration and holds promise as a readily available means of improving early newborn outcomes. In mechanically ventilated lambs, PBCC improved cardiovascular stability and reduced hypoxia. We hypothesised that PBCC compared to ECC would result in higher heart rate (HR) in infants needing resuscitation, without compromising safety.Methods and findingsBetween 4 July 2018 and 18 May 2021, infants born at ≥32+0 weeks’ gestation with a paediatrician called to attend were enrolled in a parallel-arm randomised trial at 2 Australian perinatal centres. Following initial stimulation, infants requiring further resuscitation were randomised within 60 seconds of birth using a smartphone-accessible web link. The intervention (PBCC) was to establish lung aeration, either via positive pressure ventilation (PPV) or effective spontaneous breathing, prior to cord clamping. The comparator was early cord clamping (ECC) prior to resuscitation. The primary outcome was mean HR between 60 to 120 seconds after birth, measured using 3-lead electrocardiogram, extracted from video recordings blinded to group allocation. Nonrandomised infants had deferred cord clamping (DCC) ≥120 seconds in the observational study arm.Among 508 at-risk infants enrolled, 123 were randomised (n = 63 to PBCC, n = 60 to ECC). Median (interquartile range, IQR) for gestational age was 39.9 (38.3 to 40.7) weeks in PBCC infants and 39.6 (38.4 to 40.4) weeks in ECC infants. Approximately 49% and 50% of the PBCC and ECC infants were female, respectively. Five infants (PBCC = 2, ECC = 3, 4% total) had missing primary outcome data. Cord clamping occurred at a median (IQR) of 136 (126 to 150) seconds in the PBCC arm and 37 (27 to 51) seconds in the ECC arm. Mean HR between 60 to 120 seconds after birth was 154 bpm (beats per minute) for PBCC versus 158 bpm for ECC (adjusted mean difference −6 bpm, 95% confidence interval (CI) −17 to 5 bpm, P = 0.39). Among 31 secondary outcomes, postpartum haemorrhage ≥500 ml occurred in 34% and 32% of mothers in the PBCC and ECC arms, respectively. Two hundred ninety-five nonrandomised infants (55% female) with median (IQR) gestational age of 39.6 (38.6 to 40.6) weeks received DCC. Data from these infants was used to create percentile charts of expected HR and oxygen saturation in vigorous infants receiving DCC. The trial was limited by the small number of infants requiring prolonged or advanced resuscitation. PBCC may provide other important benefits we did not measure, including improved maternal–infant bonding and higher iron stores.ConclusionsIn this study, we observed that PBCC resulted in similar mean HR compared to infants receiving ECC. The findings suggest that for infants ≥32+0 weeks’ gestation who receive brief, effective resuscitation at closely monitored births, PBCC does not provide additional benefit over ECC (performed after initial drying and stimulation) in terms of key physiological markers of transition. PBCC was feasible using a simple, low-cost strategy at both cesarean and vaginal births. The percentile charts of HR and oxygen saturation may guide clinicians monitoring the transition of at-risk infants who receive DCC.Trial registrationAustralian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12618000621213.Shiraz Badurdeen and colleagues evaluate whether physiologically-based cord clamping provides physiological benefits over early cord clamping for infants requiring resuscitation at birth. 相似文献
30.
The objective was to determine the prevalence of iodine deficiency among hypothyroid patients and the effect of dietary goitrogens
on indices of iodine and thyroid status. This is a case-control study of 106 subjects who were recruited from King Abdulaziz
University Hospital, Jeddah. Blood and urine were collected for serum thyroid hormones, thyroid autoantibodies, thyroglobulin
(Tg) and urinary iodine concentration (UIC). Dietary iodine and goitrogenic food intake were assessed by questionnaire. Using
World Health Organization (WHO) cutoff values for UIC, both controls and cases were iodine deficient (85% and 83%, respectively).
Furthermore, dietary iodine was deficient in 23% of controls and 36% of cases. In cases, there was a positive association
between UIC levels and serum thyroid stimulating hormone (r = 0.405, p < 0.01) and a negative association with serum fT4 (r = −0.358, p < 0.01). Serum Tg antibody titers were also positively associated with dietary iodine (r = 0.328, p < 0.05). Patients with elevated serum autoantibodies had lower UIC and dietary iodine than those with normal serum autoantibodies.
UIC was associated with dietary goitrogens including turnip (r = 0.280, p < 0.05) and pine (r = 0.289, p < 0.05) among cases. Iodine deficiency is common and the consumption of dietary goitrogens is high among euthyroid and hypothyroid
subjects living in Jeddah. 相似文献