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91.
Digestive Diseases and Sciences - Postoperative complication rates in patients with inflammatory bowel disease (IBD) receiving preoperative biologics have been analyzed without considering the...  相似文献   
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During 1989-1999, 11 volunteers were immunized by the bites of 1001-2927 irradiated mosquitoes harboring infectious sporozoites of Plasmodium falciparum (Pf) strain NF54 or clone 3D7/NF54. Ten volunteers were first challenged by the bites of Pf-infected mosquitoes 2-9 weeks after the last immunization, and all were protected. A volunteer challenged 10 weeks after the last immunization was not protected. Five previously protected volunteers were rechallenged 23-42 weeks after a secondary immunization, and 4 were protected. Two volunteers were protected when rechallenged with a heterologous Pf strain (7G8). In total, there was protection in 24 of 26 challenges. These results expand published findings demonstrating that immunization by exposure to thousands of mosquitoes carrying radiation-attenuated Pf sporozoites is safe and well tolerated and elicits strain-transcendent protective immunity that persists for at least 42 weeks.  相似文献   
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Hermansky-Pudlak syndrome (HPS) is an inherited hemorrhagic disease affecting the related subcellular organelles platelet dense granules, lysosomes, and melanosomes. The mouse genes for HPS, pale ear and pearl, orthologous to the human HPS1 and HPS2 (ADTB3A) genes, encode a novel protein of unknown function and the beta(3)A subunit of the AP-3 adaptor complex, respectively. To test for in vivo interactions between these genes in the production and function of intracellular organelles, mice doubly homozygous for the 2 mutant genes were produced by appropriate breeding. Cooperation between the 2 genes in melanosome production was evident in increased hypopigmentation of the coat together with dramatic quantitative and qualitative alterations of melanosomes of the retinal pigment epithelium and choroid of double mutant mice. Lysosomal and platelet dense granule abnormalities, including hyposecretion of lysosomal enzymes from kidneys and depression of serotonin concentrations of platelet dense granules were likewise more severe in double than single mutants. Also, lysosomal enzyme concentrations were significantly increased in lungs of double mutant mice. Interaction between the 2 genes was specific in that effects on organelles were confined to melanosomes, lysosomes, and platelet dense granules. Together, the evidence indicates these 2 HPS genes function largely independently at the whole organism level to affect the production and function of all 3 organelles. Further, the increased lysosomal enzyme levels in lung of double mutant mice suggest a cause of a major clinical problem of HPS, lung fibrosis. Finally, doubly mutant HPS mice are a useful laboratory model for analysis of severe HPS phenotypes.  相似文献   
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Introduction: Drug-induced liver injury (DILI) is a severe adverse drug reaction which is of major concern to patients, clinicians and the pharmaceutical industry. Accurate and rapid detection of DILI is important for patient stratification and treatment in the clinic and benefits preclinical drug design and risk assessment. MicroRNAs (miRNAs) offer a potential new and improved class of circulating biomarkers of DILI over the current gold standard biomarkers.

Areas covered: This review highlights the shortcomings of the currently used panel of biomarkers and how miRNAs, primarily miR-122, show an improved level of specificity and sensitivity in the prediction of DILI. Furthermore, the use of miRNAs as potential markers of progression of DILI and specific zonated damage within the liver is discussed.

Expert commentary: MiRNAs offer more sensitive and specific markers over the current biomarkers for DILI. Combinations of different miRNAs may be able to relay the location of DILI and the progression of disease. More studies using different hepatotoxins apart from acetaminophen will ultimately strengthen the case for the clinical introduction of miRNAs as biomarkers of DILI.  相似文献   

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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   
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We present findings from a qualitative, multisite, multi-method, longitudinal study of parents and their preschool-aged children that explores the intersections of marketing influences in the home and in the larger outside world of children. Findings indicate that preschoolers represent complicated and nuanced “consumers in training” beyond predictions based on their “perceptual stage of development.” Specifically, our data revealed interesting ways in which marketing and consumer culture can foster a number of pro-social consumer outcomes (e.g., charity, gift-giving, financial literacy). We also noted an emerging understanding by preschoolers of the social meanings of goods for identity construction and product evaluation. Finally, through a presentation of an idiographic case, we show how consumer socialization cannot be attributed to one factor such as media but is based on multiple and concurrent factors—parents, siblings, peers, and home environment—that act to moderate, mediate, and provide meaning for marketing messages.  相似文献   
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