109 research outputs found
Occupational Exposure to Mycotoxins in Swine Production: Environmental and Biological Monitoring Approaches
Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/30717100/The authors are grateful to the swine farms employers and workers that collaborate in
this research project. R.A. and C.M. are grateful to INSA and to CESAM (UID/AMB/50017/2013) through
national funds (FCT), and the co-funding by the Fundo Europeu de Desenvolvimento Regional (FEDER)
(POCI-01-0145-FEDER-00763), within the PT2020 Partnership Agreement and Compete 2020.Swine production workers are exposed simultaneously to multiple contaminants. Occupational exposure to aflatoxin B1 (AFB1) in Portuguese swine production farms has already been reported. However, besides AFB1, data regarding fungal contamination showed that exposure to other mycotoxins could be expected in this setting. The present study aimed to characterize the occupational exposure to multiple mycotoxins of swine production workers. To provide a broad view on the burden of contamination by mycotoxins and the workers’ exposure, biological (urine) samples from workers (n = 25) and 38 environmental samples (air samples, n = 23; litter samples, n = 5; feed samples, n = 10) were collected. The mycotoxins biomarkers detected in the urine samples of the workers group were the deoxynivalenol-glucuronic acid conjugate (60%), aflatoxin M1 (16%), enniatin B (4%), citrinin (8%), dihydrocitrinone (12%) and ochratoxin A (80%). Results of the control group followed the same pattern, but in general with a lower number of quantifiable results (<LOQ). Besides air samples, all the other environmental samples collected presented high and diverse contamination, and deoxynivalenol (DON), like in the biomonitoring results, was the most prominent mycotoxin. The results demonstrate that the occupational environment is adding and contributing to the workers’ total exposure to mycotoxins, particularly in the case of DON. This was confirmed by the biomonitoring data and the high contamination found in feed and litter samples. Furthermore, the followed multi-biomarker approach allowed to conclude that workers and general population are exposed to several mycotoxins simultaneously. Moreover, occupational exposure is probably described as being intermittent and with very high concentrations for short durations. This should be reflected in the risk assessment process.This research was funded by Instituto Politécnico de Lisboa, Lisbon, Portugal: Project “Bacterial
Bioburden assessment in the context of occupational exposure and animal health of swine productions
(IPL/2016/BBIOR_ESTeSL)” and also by FCT—Fundação para Ciência e Tecnologia: Project “EXPOsE –
Establishing protocols to assess occupational exposure to microbiota in clinical settings (02/SAICT/2016 – Project nº 23222)”.info:eu-repo/semantics/publishedVersio
An Immunologically Privileged Retinal Antigen Elicits Tolerance: Major Role for Central Selection Mechanisms
Immunologically privileged retinal antigens can serve as targets of experimental autoimmune uveitis (EAU), a model for human uveitis. The tolerance status of susceptible strains, whose target antigen is not expressed in the thymus at detectable levels, is unclear. Here, we address this issue directly by analyzing the consequences of genetic deficiency versus sufficiency of a uveitogenic retinal antigen, interphotoreceptor retinoid-binding protein (IRBP). IRBP-knockout (KO) and wild-type (WT) mice on a highly EAU-susceptible background were challenged with IRBP. The KO mice had greatly elevated responses to IRBP, an altered recognition of IRBP epitopes, and their primed T cells induced exacerbated disease in WT recipients. Ultrasensitive immunohistochemical staining visualized sparse IRBP-positive cells, undetectable by conventional assays, in thymi of WT (but not of KO) mice. IRBP message was PCR amplified from these cells after microdissection. Thymus transplantation between KO and WT hosts demonstrated that this level of expression is functionally relevant and sets the threshold of immune (and autoimmune) reactivity. Namely, KO recipients of WT thymi generated reduced IRBP-specific responses, and WT recipients of KO thymi developed enhanced responses and a highly exacerbated disease. Repertoire culling and thymus-dependent CD25+ T cells were implicated in this effect. Thus, uveitis-susceptible individuals display a detectable and functionally significant tolerance to their target antigen, in which central mechanisms play a prominent role
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'Leader, you first': The everyday production of hierarchical space in a Chinese bureaucracy
Recent studies highlight how organizational power relations are materialized in space. However, relatively little is known about how these spatialized power relations are reproduced on a day-to-day basis. Drawing on a ten-month ethnographic study of a large government office in China, we find that hierarchical space is produced through three intertwined processes. It proliferates as employees actively seek out signs of hierarchy in the organization’s space; it becomes familiarized as employees fabricate and circulate fanciful narratives about their spatial environs; and it is ritualized by employees acting out hierarchical relations across the organization’s space. These processes resulted in a hardening of the hierarchical relations of power. The study extends the existing literature by showing how hierarchical organizational space is not just something that is imposed on employees; it is also imposed by the employees themselves
Erratum to: Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive cases
Erratum to: Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive case
Abnormal Changes in NKT Cells, the IGF-1 Axis, and Liver Pathology in an Animal Model of ALS
Amyotrophic lateral sclerosis (ALS) is a rapidly progressing fatal neurodegenerative disorder characterized by the selective death of motor neurons (MN) in the spinal cord, and is associated with local neuroinflammation. Circulating CD4+ T cells are required for controlling the local detrimental inflammation in neurodegenerative diseases, and for supporting neuronal survival, including that of MN. T-cell deficiency increases neuronal loss, while boosting T cell levels reduces it. Here, we show that in the mutant superoxide dismutase 1 G93A (mSOD1) mouse model of ALS, the levels of natural killer T (NKT) cells increased dramatically, and T-cell distribution was altered both in lymphoid organs and in the spinal cord relative to wild-type mice. The most significant elevation of NKT cells was observed in the liver, concomitant with organ atrophy. Hepatic expression levels of insulin-like growth factor (IGF)-1 decreased, while the expression of IGF binding protein (IGFBP)-1 was augmented by more than 20-fold in mSOD1 mice relative to wild-type animals. Moreover, hepatic lymphocytes of pre-symptomatic mSOD1 mice were found to secrete significantly higher levels of cytokines when stimulated with an NKT ligand, ex-vivo. Immunomodulation of NKT cells using an analogue of α-galactosyl ceramide (α-GalCer), in a specific regimen, diminished the number of these cells in the periphery, and induced recruitment of T cells into the affected spinal cord, leading to a modest but significant prolongation of life span of mSOD1 mice. These results identify NKT cells as potential players in ALS, and the liver as an additional site of major pathology in this disease, thereby emphasizing that ALS is not only a non-cell autonomous, but a non-tissue autonomous disease, as well. Moreover, the results suggest potential new therapeutic targets such as the liver for immunomodulatory intervention for modifying the disease, in addition to MN-based neuroprotection and systemic treatments aimed at reducing oxidative stress
Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive cases
Cancer-associated retinopathy (CAR) in neuroendocrine carcinoma of the uterus
A75-year-old female patient presented with bilateral progressive loss of vision. Best corrected visual acuity (BCVA) was hand movements in the right eye and 1/50 in the left eye. The spectral domain optical coherence tomography (SD-OCT) showed thinning of the outer retina suspected to be due to autoimmune retinopathy. Aneuroendocrine carcinoma of the uterus was diagnosed during tumor screening. Under systemic therapy with corticosteroids the visual acuity improved to 20/200 in the right eye and 20/80 in the left eye. Cancer-associated retinopathy (CAR) is aparaneoplastic autoimmune retinopathy
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