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1.
Jessica Gall Myrick Avery E. Holton Itai Himelboim Brad Love 《Health communication》2016,31(5):596-605
Social network sites (SNSs) like Twitter continue to attract users, many of whom turn to these spaces for social support for serious illnesses like cancer. Building on literature that explored the functionality of online spaces for health-related social support, we propose a typology that situates this type of support in an SNS-based open cancer community based on the type (informational or emotional) and the direction (expression or reception) of support. A content analysis applied the typology to a 2-year span of Twitter messages using the popular hashtag “#stupidcancer.” Given that emotions form the basis for much of human communication and behavior, including aspects of social support, this content analysis also examined the relationship between emotional expression and online social support in tweets about cancer. Furthermore, this study looked at the various ways in which Twitter allows for message sharing across a user’s entire network (not just among the cancer community). This work thus begins to lay the conceptual and empirical groundwork for future research testing the effects of various types of social support in open, interactive online cancer communities. 相似文献
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While the resistance of bacteria to traditional antibiotics is a major public health concern, the use of extremely potent antibacterial agents is limited by their lack of selectivity. As in cancer therapy, antibacterial targeted therapy could provide an opportunity to reintroduce toxic substances to the antibacterial arsenal. A desirable targeted antibacterial agent should combine binding specificity, a large drug payload per binding event, and a programmed drug release mechanism. Recently, we presented a novel application of filamentous bacteriophages as targeted drug carriers that could partially inhibit the growth of Staphylococcus aureus bacteria. This partial success was due to limitations of drug-loading capacity that resulted from the hydrophobicity of the drug. Here we present a novel drug conjugation chemistry which is based on connecting hydrophobic drugs to the phage via aminoglycoside antibiotics that serve as solubility-enhancing branched linkers. This new formulation allowed a significantly larger drug-carrying capacity of the phages, resulting in a drastic improvement in their performance as targeted drug-carrying nanoparticles. As an example for a potential systemic use for potent agents that are limited for topical use, we present antibody-targeted phage nanoparticles that carry a large payload of the hemolytic antibiotic chloramphenicol connected through the aminoglycoside neomycin. We demonstrate complete growth inhibition toward the pathogens Staphylococcus aureus, Streptococcus pyogenes, and Escherichia coli with an improvement in potency by a factor of approximately 20,000 compared to the free drug. 相似文献
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Shay Weiss Zeev Altboum Itai Glinert Josef Schlomovitz Assa Sittner Elad Bar-David David Kobiler Haim Levy 《Antimicrobial agents and chemotherapy》2015,59(12):7497-7503
Respiratory anthrax is a fatal disease in the absence of early treatment with antibiotics. Rabbits are highly susceptible to infection with Bacillus anthracis spores by intranasal instillation, succumbing within 2 to 4 days postinfection. This study aims to test the efficiency of antibiotic therapy to treat systemic anthrax in this relevant animal model. Delaying the initiation of antibiotic administration to more than 24 h postinfection resulted in animals with systemic anthrax in various degrees of bacteremia and toxemia. As the onset of symptoms in humans was reported to start on days 1 to 7 postexposure, delaying the initiation of treatment by 24 to 48 h (time frame for mass distribution of antibiotics) may result in sick populations. We evaluated the efficacy of antibiotic administration as a function of bacteremia levels at the time of treatment initiation. Here we compare the efficacy of treatment with clarithromycin, amoxicillin-clavulanic acid (Augmentin), imipenem, vancomycin, rifampin, and linezolid to the previously reported efficacy of doxycycline and ciprofloxacin. We demonstrate that treatment with amoxicillin-clavulanic acid, imipenem, vancomycin, and linezolid were as effective as doxycycline and ciprofloxacin, curing rabbits exhibiting bacteremia levels of up to 105 CFU/ml. Clarithromycin and rifampin were shown to be effective only as a postexposure prophylactic treatment but failed to treat the systemic (bacteremic) phase of anthrax. Furthermore, we evaluate the contribution of combined treatment of clindamycin and ciprofloxacin, which demonstrated improvement in efficacy compared to ciprofloxacin alone. 相似文献
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Maria H. Harris Diane R. Gold Sheryl L. Rifas-Shiman Steven J. Melly Antonella Zanobetti Brent A. Coull Joel D. Schwartz Alexandros Gryparis Itai Kloog Petros Koutrakis David C. Bellinger Roberta F. White Sharon K. Sagiv Emily Oken 《Environmental health perspectives》2015,123(10):1072-1078
Background
Influences of prenatal and early-life exposures to air pollution on cognition are not well understood.Objectives
We examined associations of gestational and childhood exposure to traffic-related pollution with childhood cognition.Methods
We studied 1,109 mother–child pairs in Project Viva, a prospective birth cohort study in eastern Massachusetts (USA). In mid-childhood (mean age, 8.0 years), we measured verbal and nonverbal intelligence, visual motor abilities, and visual memory. For periods in late pregnancy and childhood, we estimated spatially and temporally resolved black carbon (BC) and fine particulate matter (PM2.5) exposures, residential proximity to major roadways, and near-residence traffic density. We used linear regression models to examine associations of exposures with cognitive assessment scores, adjusted for potential confounders.Results
Compared with children living ≥ 200 m from a major roadway at birth, those living < 50 m away had lower nonverbal IQ [–7.5 points; 95% confidence interval (CI): –13.1, –1.9], and somewhat lower verbal IQ (–3.8 points; 95% CI: –8.2, 0.6) and visual motor abilities (–5.3 points; 95% CI: –11.0, 0.4). Cross-sectional associations of major roadway proximity and cognition at mid-childhood were weaker. Prenatal and childhood exposure to traffic density and PM2.5 did not appear to be associated with poorer cognitive performance. Third-trimester and childhood BC exposures were associated with lower verbal IQ in minimally adjusted models; but after adjustment for socioeconomic covariates, associations were attenuated or reversed.Conclusions
Residential proximity to major roadways during gestation and early life may affect cognitive development. Influences of pollutants and socioeconomic conditions on cognition may be difficult to disentangle.Citation
Harris MH, Gold DR, Rifas-Shiman SL, Melly SJ, Zanobetti A, Coull BA, Schwartz JD, Gryparis A, Kloog I, Koutrakis P, Bellinger DC, White RF, Sagiv SK, Oken E. 2015. Prenatal and childhood traffic-related pollution exposure and childhood cognition in the Project Viva cohort (Massachusetts, USA). Environ Health Perspect 123:1072–1078; http://dx.doi.org/10.1289/ehp.1408803 相似文献8.
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Mai Shimura Hiroshi Ishikawa Hiromi Nagase Akihiko Mochizuki Futoshi Sekiguchi Naho Koshimizu Toshiyuki Itai Mizuha Odagami 《Congenital anomalies》2018,58(5):167-170
We investigated whether it was possible to predict the prognosis of fetuses with cystic hygroma in early pregnancy based on the degree of neck thickening. We retrospectively analyzed 57 singleton pregnancies with fetuses with cystic hygroma who were examined before the 22nd week of pregnancy. The fetuses were categorized according to the outcome, structural abnormalities at birth, and chromosomal abnormalities. Here, we proposed a new sonographic predictor with which we assessed neck thickening by dividing the width of the neck thickening by the biparietal diameter, which is expressed as the cystic hygroma width/biparietal diameter ratio. The median cystic hygroma width/biparietal diameter ratio in the intrauterine fetal death group (0.51) was significantly higher than that in the live birth group (0.27). No significant difference in the median cystic hygroma width/biparietal diameter ratio was found between the structural abnormalities group at birth and the no structural abnormalities group, and no significant difference in the median cystic hygroma width/biparietal diameter ratio was found between the chromosomal abnormality group and the no chromosomal abnormality group. We used receiver operating characteristic analysis to evaluate the cystic hygroma width/biparietal diameter ratio to predict intrauterine fetal death. When the cystic hygroma width/biparietal diameter ratio cut‐off value was 0.5, intrauterine fetal death could be predicted with a sensitivity of 52.9% and a specificity of 100%. It is possible to predict intrauterine fetal death in fetuses with cystic hygroma in early pregnancy if cystic hygroma width/biparietal diameter ratio is measured. However, even if cystic hygroma width/biparietal diameter ratio is measured, predicting the presence or absence of a structural abnormality at birth or a chromosomal abnormality is difficult. 相似文献
10.
Lior Hassan Tal Pecht Nir Goldstein Yulia Haim Itai Kloog Shaked Yarza 《Journal of toxicology and environmental health. Part A》2019,82(9):564-576
ABSTRACTThe effects of particulate matter (PM) air pollution on adipose tissue have mainly been studied in animal models. The aim of this study was to examine the potential associations between PM exposure and 25 cellular markers in human omental (OM) and subcutaneous (SC) adipose tissue. The PM exposure assessments for both PM2.5 (PM <2.5 μm in diameter) and PM10 (<10 μm) were based upon a novel hybrid satellite-based spatio-temporally resolved model. We calculated the PM exposure above the background threshold for 1 week (acute phase), 3 and 6 months (intermediate phase), and 1 year (chronic phase) prior to tissue harvesting and tested the associations with adipose cell metabolic effects using multiple linear regressions and heat maps strategy. Chemokine levels were found to increase after acute and intermediate exposure duration to PM10. The levels of stress signaling biomarkers in the SC and OM tissues rose after acute exposure to PM10 and PM2.5. Macrophage and leucocyte counts were associated with severity of PM exposure in all three duration groups. Adipocyte diameter decreased in all exposure periods. Our results provide evidence for significant contribution of air pollutants exposure to adipose tissue inflammation as well as for pathophysiological mechanisms of metabolic dysregulation that may be involved in the observed responses. 相似文献