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81.
Monaghan G McLellan A McGeehan A Li Volti S Mollica F Salemi I Din Z Cassidy A Hume R Burchell B 《The Journal of pediatrics》1999,134(4):441-446
OBJECTIVE: Prolonged neonatal jaundice, beyond day 14 of life, is very common and of concern to the clinician. The aim of this study was to investigate whether a genetic mutation in the bilirubin UGT1A1 gene, which has been associated with Gilbert's syndrome in adults, is a contributory factor in prolonged neonatal jaundice. STUDY DESIGN: Blood was collected from 85 term newborns with unexplained hyperbilirubinemia, and DNA was prepared. The neonates were divided into 6 groups depending on whether they were breast-fed or bottle-fed and whether they had acute, prolonged, or very prolonged jaundice. UGT1A1 TATA promoter genotyping (DNA test for Gilbert's syndrome) was performed on all samples, and analysis of the entire UGT1A1 coding sequence was performed in a representative sample (11 of 26) of very prolonged cases. RESULTS: In addition to the known common UGT1A1 TATA alleles (TA6 and TA7), a novel TATA allele (TA5) in a neonate with very prolonged jaundice was identified. Statistical analysis of the TATA genotype distributions within the group of breast-fed neonates revealed significant differences among the acute, prolonged, and very prolonged subgroups (.05 > P >.01): the incidence of familial hyperbilirubinemia genotypes (7/7 and 5/7) is 5 times greater in very prolonged cases (31%) relative to acute cases (6%). Neonates with prolonged jaundice from family pedigrees were observed to demonstrate the Gilbert's phenotype as children or young adults. CONCLUSIONS: A genetic predisposition to develop prolonged neonatal hyperbilirubinemia in breast-fed infants is associated with TATA box polymorphism of the UGT1A1 gene and will be recognized as Gilbert's syndrome in adulthood. 相似文献
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James J. Elser Shawn P. Devlin Jinlei Yu Adam Baumann Matthew J. Church John E. Dore Robert O. Hall Jr. Melody Hollar Tyler Johnson Trista Vick-Majors Cassidy White 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(30)
Considerable attention is given to absolute nutrient levels in lakes, rivers, and oceans, but less is paid to their relative concentrations, their nitrogen:phosphorus (N:P) stoichiometry, and the consequences of imbalanced stoichiometry. Here, we report 38 y of nutrient dynamics in Flathead Lake, a large oligotrophic lake in Montana, and its inflows. While nutrient levels were low, the lake had sustained high total N: total P ratios (TN:TP: 60 to 90:1 molar) throughout the observation period. N and P loading to the lake as well as loading N:P ratios varied considerably among years but showed no systematic long-term trend. Surprisingly, TN:TP ratios in river inflows were consistently lower than in the lake, suggesting that forms of P in riverine loading are removed preferentially to N. In-lake processes, such as differential sedimentation of P relative to N or accumulation of fixed N in excess of denitrification, likely also operate to maintain the lake’s high TN:TP ratios. Regardless of causes, the lake’s stoichiometric imbalance is manifested in P limitation of phytoplankton growth during early and midsummer, resulting in high C:P and N:P ratios in suspended particulate matter that propagate P limitation to zooplankton. Finally, the lake’s imbalanced N:P stoichiometry appears to raise the potential for aerobic methane production via metabolism of phosphonate compounds by P-limited microbes. These data highlight the importance of not only absolute N and P levels in aquatic ecosystems, but also their stoichiometric balance, and they call attention to potential management implications of high N:P ratios.The emergence of the Anthropocene era has been marked by major changes in all of Earth’s major biogeochemical cycles (1). For example, fluxes of carbon (C) (as CO2) to the atmosphere have increased by ∼14% during the last 120 y largely due to fossil fuel combustion. Fluxes of nitrogen (N) into the biosphere have increased by at least 100% due to application of the Haber-Bosch reaction for fertilizer production, land use change favoring N-fixing legumes, and conversion of atmospheric N2 to available forms (NOx) by high temperature combustion of petroleum and fossil gas (2). Finally, large-scale mining of phosphorus (P)-rich geological deposits for production of fertilizers has amplified rates of P cycling in the biosphere by ∼400% (1). Each of these perturbations has biophysical and ecological impacts at differing time and space scales. For C, its accumulation in the atmosphere has altered Earth’s radiative balance, warming the planet and perturbing precipitation patterns globally. Amplified inputs of reactive N to the Earth system enter the hydrosphere and, thus, potentially lead to overenrichment of lakes, rivers, and coastal oceans across broad regions. Amplifications of P inputs often impair water quality at watershed and local scales (3), stimulating phytoplankton production and contributing, along with N, to harmful algal blooms, fish kills, and “dead zones” (4, 5). These differential amplifications and their contrasting spatial scales indicate that ecosystems are experiencing not only absolute changes in biogeochemical cycling, but also perturbations in the relative inputs and outputs of biologically important elements (6). Studies of elemental coupling and uncoupling in ecosystems are not yet widespread, but emerging work has shown how C, N, and P are differentially processed as they pass through watersheds (7).The potential for differential alteration in supplies of N and P to aquatic ecosystems suggests that understanding the nutrient status of a water body requires knowledge of not only absolute supplies of limiting nutrients, but also their relative proportions (i.e., their N:P stoichiometry). This work has been facilitated in recent years by the emergence of the theory of ecological stoichiometry (8). For example, seminal work by Redfield (9) found that N:P ratios in marine organic matter were tightly constrained around 16:1 (molar, here and throughout), a value that may represent the central tendency for the N:P ratio of phytoplankton undergoing balanced growth in which major pools of N (protein) and P (RNA) are produced at the same rate (10). In lakes, N:P ratios show much wider variation—around a value of ∼30—perhaps reflecting the biogeochemical connections of lakes to terrestrial systems where N:P ratios have a similar value and range of variation (11). Nevertheless, this classic “Redfield ratio” of 16:1 can be thought of as representing a balanced nutrient supply for primary producers in pelagic ecosystems. When the ratios of N and P supplied deviate from this balanced ratio, primary limitation of growth by N (when N:P is low) or by P (when N:P is high) can occur. For example, phytoplankton growth in lakes with imbalanced total N: total P (TN:TP) ratios that exceed 30:1 is generally P limited (12). Disproportionate inputs of N relative to P from atmospheric deposition can increase lake TN:TP ratios and shift lake phytoplankton from N to P limitation (13), inducing P limitation in zooplankton (14). Imbalanced N:P ratios in nutrient supplies can also shift the competitive advantage among phytoplankton and enhance production of potentially toxic compounds during harmful algal blooms. For example, skewed supplies of N relative to P can increase production of N-rich secondary compounds by phytoplankton, while disproportionate inputs of P relative to N can induce production of C-based toxins (15). High N:P ratios can also enhance proliferation of fungal parasites of phytoplankton (16).Imbalanced N:P ratios can impact aquatic ecosystems in other ways. For example, they can alter the functioning of food webs. In particular, shifts in nutrient supply regimes that enhance P limitation can impede energy flow in trophic interactions because biomass of P-limited primary producers is of low quality for animals due to its low P content (8). Ecosystem shifts to high N:P ratios and more prevalent P limitation can also impact the cycling of the greenhouse-active gas methane (CH4) because phosphate limitation can result in production of methane under aerobic conditions in both marine and freshwater phytoplankton and bacteria (17, 18). Both chemoheterotrophic and photoautotrophic bacteria (e.g., Pseudomonas, SAR11, Trichodesmium, Synechococcus) can metabolize organic P compounds, called phosphonates, to acquire P. Microbial cleavage of one type of phosphonate, methylphosphonic acid (MPn), to acquire P results in formation of methane (17). While it is likely that anaerobic methane production due to oxygen depletion in response to P-driven eutrophication is the dominant process connecting P to methane dynamics, the significance of aerobic phosphonate metabolism to global methane cycles remains to be assessed. However, contributions are potentially large, given the prevalence of P limitation in both freshwater and marine ecosystems. In light of emerging trends that suggest overall increases in ecosystem N:P ratios due to human impacts (6), these trophic and biogeochemical impacts of stoichiometric imbalance show that it is critical to consider not only absolute levels of nutrients, but also their stoichiometry. In particular, high N:P ratios can accentuate P limitation, causing a suite of ecological impacts that, currently, are poorly described.In this paper, we illustrate the utility of stoichiometric approaches by combining analyses of long-term records of nutrient supply and dynamics, together with contemporary experiments, to examine how imbalances in N:P stoichiometry (e.g., strong divergence from classic Redfield proportions) influence plankton ecology and biogeochemistry across multiple scales in Flathead Lake, a large lake in western Montana. The lake is itself relatively unperturbed by human impacts and, thus, maintains low overall nutrient levels. However, the strong stoichiometric imbalance that we describe makes Flathead Lake appropriate for assessing ecosystem consequences of what appear to be general trends of increasing N:P ratios in global ecosystems (6). Numerous limnological properties of the lake and its inflow rivers have been monitored continuously for several decades, including concentrations of various forms of N and P. Thus, these time-series data allow us not only to assess long-term variability or stability in the stoichiometry of N and P in the lake and its river inflows over decadal time scales, but also to connect its stoichiometry with potential consequences for nutrient limitation, food web dynamics, and biogeochemical cycling under low-nutrient conditions. 相似文献
84.
R. E. Petty J. T. Cassidy R. Heyn A. G. Kenien R. L. Washburn 《Arthritis \u0026amp; Rheumatology》1976,19(5):902-906
Although an uncommon occurrence in childhood, hypertrophic osteoarthropathy secondary to tumors—most commonly to osteogenic sarcoma with pulmonary metastasis—may cause severe joint pain and swelling. The syndrome should be considered in the differential diagnosis of acute arthritis in childhood. 相似文献
85.
Kenneth Wengler Brandon K. Ashinoff Elena Pueraro Clifford M. Cassidy Guillermo Horga Bret R. Rutherford 《Neuropsychopharmacology》2021,46(7):1233
Late-life depression (LLD) is a prevalent and disabling condition in older adults that is often accompanied by slowed processing and gait speed. These symptoms are related to impaired dopamine function and sometimes remedied by levodopa (L-DOPA). In this study, we recruited 33 older adults with LLD to determine the association between a proxy measure of dopamine function—neuromelanin-sensitive magnetic resonance imaging (NM-MRI)—and baseline slowing measured by the Digit Symbol test and a gait speed paradigm. In secondary analyses, we also assessed the ability of NM-MRI to predict L-DOPA treatment response in a subset of these patients (N = 15) who received 3 weeks of L-DOPA. We scanned a further subset of these patients (N = 6) with NM-MRI at baseline and after treatment to preliminarily evaluate the effects of L-DOPA treatment on the NM-MRI signal. We found that lower baseline NM-MRI correlated with slower baseline gait speed (346 of 1807 substantia nigra–ventral tegmental area (SN-VTA) voxels, Pcorrected = 0.038), particularly in the more medial, anterior, and dorsal SN-VTA. Secondary analyses failed to show an association between baseline NM-MRI and treatment-related changes in gait speed, processing speed, or depression severity (all Pcorrected > 0.361); we however found preliminary evidence of increases in the NM-MRI signal 3 weeks post-treatment with L-DOPA compared to baseline (200 of 1807 SN-VTA voxels; Pcorrected = 0.046), although the small sample size of these preliminary analyses warrants caution in their interpretation and future replications. Overall, our findings indicate that NM-MRI is sensitive to variability in gait speed in patients with LLD, suggesting this non-invasive MRI measure may provide a promising marker for dopamine-related psychomotor slowing in geriatric neuropsychiatry.Subject terms: Cognitive neuroscience, Depression, Biomarkers 相似文献
86.
Buprenorphine is considered one of the most effective treatments for opioid use disorder and significantly reduces risk of overdose death. However, concerns about its diversion and misuse have often taken center stage in public discourse and in the design of practices and policies regarding its use. This has been to the detriment of many vulnerable patient populations, especially those involved in the criminal justice system. Policies that restrict access to buprenorphine in criminal justice and other settings due to concerns of diversion do not accurately reflect the relative risks and safety profile associated with it, creating unnecessary barriers that drive an illicit market of this much-needed medication. Although proper regulation of all controlled medications should be a priority, in most instances the benefits of buprenorphine highly outweigh its risks. In the midst of a national crisis, efforts should be focused on expanding, and not restricting, access to this lifesaving treatment. 相似文献
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Katie Fisher Brenda Cassidy Dianxu Ren Ann M. Mitchell 《Journal of community health nursing》2018,35(2):41-48
A bully is defined as anyone who participates in any form of repetitive negative and hurtful behavior, with the intent of inflicting harm (Highmark & Center for Safe Schools, 2013). Purpose: The purpose of this project was to evaluate the feasibility of implementing a bullying awareness, prevention, and screening program for teachers and school nurses. Methods: The sample included 174 fifth-graders from a public-school district in rural, southwestern Pennsylvania. Teachers received an educational program and students were screened for bullying using the PIPSQ. Results: Although not a significant finding, there was an increase in teacher’s knowledge post-education (p = 0.515). Although findings were not significant, the results of the PIPSQ revealed greater victimization in this school (M = 6.93), with bullying behaviors greater among boys (p = 0.000). Conclusions: The educational program and the PIPSQ tool appear to be a promising method to identify victimization and bullying within an elementary school setting; further research can determine significance of screening and faculty education. 相似文献
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Secreted products of Fasciola hepatica inhibit the induction of T cell responses that mediate allergy
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C. M. Finlay A. M. Stefanska M. M. Coleman H. Jahns J. P. Cassidy R. M. McLoughlin K. H. G. Mills 《Parasite immunology》2017,39(10)
There is evidence from epidemiology studies of a negative association between infection with helminth parasites and the development of allergy and asthma. Here, we demonstrate that the excretory/secretory products of the helminth Fasciola hepatica (FHES) protected mice against ovalbumin (OVA)‐induced allergic asthma when administered at time of allergen sensitization. FHES reduced the accumulation of mucus, eosinophils and lymphocytes into the airways of allergen‐challenged mice. Furthermore, FHES treatment suppressed Th2 responses in the airways. Interestingly, systemic administration of FHES at allergen challenge had no effect on airway inflammation, demonstrating that alum‐induced Th2 response is set following initial allergen sensitization. Our findings highlight the immunomodulatory potential of molecules secreted by F. hepatica. 相似文献