Comparison of Recreational Fish Consumption Advisories Across the USA.

PURPOSE OF REVIEW: Our comparative analysis sought to understand the factors which drive differences in fish consumption advisories across the USA - including exposure scenarios (acute and chronic health risk, non-cancer and cancer health endpoints), toxicity values (reference dose, cancer slope factor, acute tolerance level), and meal size and bodyweight assumptions. RECENT FINDINGS: Fish consumption provides essential nutrients but also results in exposure to contaminants such as PCBs and methylmercury. To protect consumers from the risks of fish contaminants, fish consumption advisories are established, most often by state jurisdictions, to estimate the amount of a certain fish species a person could consume throughout their lifetime without harm. However, inconsistencies in advisories across the USA confuse consumers and undermine the public health goals of fish advisory programs. To date, no rigorous comparison of state and national fish consumption advisories has been reported. Our work identifies discrepancies in key assumptions used to derive risk-based advisories between US states, reflecting differences in the interpretation of toxicity science. We also address the implications for these differences by reviewing advisories issued by contiguous states bordering two waterbodies: Lake Michigan and the Lower Mississippi River. Our findings highlight the importance of regional collaboration when issuing advisories, so that consumers of self-caught fish are equipped with clear knowledge to make decisions to protect their health.

Dynamics of Cadmium Acclimation in Daphnia pulex: Linking Fitness Costs, Cross-Tolerance, and Hyper-Induction of Metallothionein.

Acclimation increases tolerance to stress in individuals but is assumed to contribute fitness costs when the stressor is absent, though data supporting this widely held claim are sparse. Therefore, using clonal (i.e., genetically identical) cultures of Daphnia pulex, we isolated the contributions of acclimation to the regulation of the metal response gene, metallothionein 1 (MT1), and defined the reproductive benefits and costs of cadmium (Cd)-acclimation. Daphnia pulex were exposed for 50 parthenogenetic generations to environmentally realistic levels (1 µg Cd/L), and tolerance to Cd and other metals assessed during this period via standard toxicity tests. These tests revealed (1) increased tolerance to Cd compared to genetically identical nonacclimated cultures, (2) fitness costs in Cd-acclimated Daphnia when Cd was removed, and (3) cross-tolerance of Cd-acclimated Daphnia to zinc and silver, but not arsenic, thereby defining a functional role for metallothionein. Indeed, Cd-acclimated clones had significantly higher expression of MT1 mRNA than nonacclimated clones, when Cd exposed. Both the enhanced induction of MT1 and tolerant phenotype were rapidly lost when Cd was removed (1-2 generations), which is further evidence of acclimation costs. These findings provide evidence for the widely held view that acclimation is costly and are important for investigating evolutionary principles of genetic assimilation and the survival mechanisms of natural populations that face changing environments.

Extensive Postradiation Ocular and Diffuse Cranial Neuromyotonia Mimicking Myasthenia Gravis.

BACKGROUND: Ocular neuromyotonia is a rare, but well-recognized, complication of cranial irradiation. CASE REPORT: Using figures and videos, we report a 52-year-old man with extensive ocular, brainstem, and lower cranial nerve neuromyotonia postradiation therapy for a fourth ventricle glioma who, in the context of an apparently positive edrophonium test, was initially misdiagnosed with myasthenia gravis. CONCLUSIONS: This is the first case of postirradiation neuromyotonia to be reported with such extensive cranial nerve and brainstem involvement.

CD47 deficiency ameliorates autoimmune nephritis in Fas(lpr) mice by suppressing IgG autoantibody production.

CD47, a self-recognition marker, plays an important role in both innate and adaptive immune responses. To explore the potential role of CD47 in activation of autoreactive T and B cells and the production of autoantibodies in autoimmune disease, especially systemic lupus erythematosus (SLE), we have generated CD47 knockout Fas(lpr) (CD47(-/-) -Fas(lpr) ) mice and examined histopathological changes in the kidneys, cumulative survival rates, proteinuria, extent of splenomegaly and autoantibodies, serum chemistry and immunological parameters. In comparison with Fas(lpr) mice, CD47(-/-) -Fas(lpr) mice exhibit a prolonged lifespan and delayed autoimmune nephritis, including glomerular cell proliferation, basement membrane thickening, acute tubular atrophy and vacuolization. CD47(-/-) -Fas(lpr) mice have lower levels of proteinuria, associated with reduced deposition of complement C3 and C1q, and IgG but not IgM in the glomeruli, compared to age-matched Fas(lpr) mice. Serum levels of antinuclear antibodies and anti-double-stranded DNA antibodies are significantly lower in CD47(-/-) -Fas(lpr) than in Fas(lpr) mice. CD47(-/-) -Fas(lpr) mice also display less pronounced splenomegaly than Fas(lpr) mice. The mechanistic studies further suggest that CD47 deficiency impairs the antigenic challenge-induced production of IgG but not IgM, and that this effect is associated with reduction of T follicular cells and impairment of germinal centre development in lymphoid tissues. In conclusion, our results demonstrate that CD47 deficiency ameliorates lupus nephritis in Fas(lpr) mice via suppression of IgG autoantibody production.

Successful treatment of fingolimod-associated macular edema with intravitreal triamcinolone with continued fingolimod use.

The occurrence of macular edema as an adverse effect of fingolimod is well documented. Treatment modalities used to manage fingolimod-associated macular edema (FAME) have included nonsteroidal anti-inflammatory agents and sub-tenon injection. We describe two cases where intravitreal injection is used to successfully treat FAME in patients who were previously unsuccessfully treated with topical nonsteroidal anti-inflammatories.

Temporal arteritis.

Temporal or giant cell arteritis is an inflammation of medium and small extracranial vessels that may result in ocular ischemia, an aortitis followed by aortic dissection and peripheral limb ischemia. It should be considered a medical emergency due to the seriousness of end organ damage, in particular visual symptoms. While the presentation may be nonspecific, the presence of a tender temporal artery mandates a temporal artery biopsy. High-dose steroids should be begun the moment the diagnosis is considered and only withdrawn once it has been excluded. A gradual tapering of the steroid dose should occur over at least 1 year, with the consideration of the use of steroid-sparing agents if iatrogenic steroid complications occur. Careful monitoring of the response both clinically as well as with serial inflammatory markers is required.

Fingolimod and macular edema: Pathophysiology, diagnosis, and management.

Fingolimod causes macular edema (ME) by acting via the S1P3 receptor agonism, thereby reducing the tight junction between the endothelial cells of the retinal capillaries. This results in the breakdown of the inner blood retinal barrier, causing ME. Ophthalmologic evaluation including optical coherence tomography is recommended at baseline and then at 3 months, 6 months, and annually thereafter in all patients on fingolimod. The risk of ME increases in patients who are diabetic, have had uveitis, or who undergo intraocular procedures such as cataract surgery, and hence these patients need close monitoring. Cessation of the drug results in resolution of the ME. However, ME can also be treated using anti-inflammatory medication (steroids) in patients who opt to remain on fingolimod.

Concurrent central retinal artery occlusion and branch retinal vein occlusion in giant cell arteritis.

Ophthalmic involvement in giant cell arteritis can manifest in a number of ways. Central retinal artery occlusion is one of the common causes of visual loss in giant cell arteritis. On the contrary, branch retinal vein occlusion is rarely associated with the latter. We report an 89-year-old lady with acute left central retinal artery occlusion on a background of progressive decline in vision over a 6-month period with a concurrent right branch retinal vein occlusion. Subsequent investigation confirmed giant cell arteritis on temporal artery biopsy. This is the first reported case of a concurrent central retinal artery occlusion and branch retinal vein occlusion in giant cell arteritis, and highlights the various ocular presentations that can occur in giant cell arteritis.

Clinicopathological correlation in pituitary gland metastasis presenting as anterior visual pathway compression.

Pituitary gland metastases, albeit rare, remain an important differential in sellar and suprasellar tumours. Clinical and radiological features of pituitary metastases may be indistinguishable from benign suprasellar lesions such as a pituitary adenoma. Histopathology with immunohistochemical assay remains the key to the diagnosis of pituitary metastasis. We describe four patients with sellar lesions presenting with anterior visual pathway compression initially diagnosed as pituitary adenomas who on immunohistochemistry were found to have metastases to the pituitary. Classification of the cell histology determined the primary site of origin in some patients. This series demonstrates the importance of combining histopathology and immunohistochemistry in the diagnosis of suprasellar lesions.

Isolated unilateral abducens cranial nerve palsy: a rare presentation of pituitary apoplexy.

PURPOSE: To describe a rare presentation of pituitary apoplexy as unilateral abducens nerve palsy demonstrating the various presentations of the condition. METHODS: Case report. RESULTS: A 48-year-old man presented with isolated right abducens nerve palsy. Magnetic resonance imaging showed a large pituitary macroadenoma with evidence of recent bleed into the right cavernous sinus and surrounding the right internal carotid artery. CONCLUSIONS: Pituitary apoplexy may present subtly with an isolated sixth nerve palsy but the condition is critical and high index of suspicion needs to be governed.

Vision-related quality of life in patients with complete homonymous hemianopia post stroke.

PURPOSE: The aim is to determine the characteristics of vision-specific quality of life restriction using the National Eye Institute Visual Function Questionnaire (NEI VFQ-25) and Veterans Affairs Low Vision Visual Function Questionnaire (VA LV VFQ-48) in patients with complete homonymous hemianopia (HH) post stroke. METHOD: Prospective cohort study of patients with complete HH compared to age- and gender-matched subjects with normal visual fields. RESULTS: In the NEI VFQ-25, scores on five subscales were significantly reduced after multiple logistic regression accounting for vision and comorbidities. The five subscales are vision-specific social functioning, vision-specific mental health, vision-specific dependency, driving, and peripheral vision. In the VA LV VFQ-48 postregression analysis, mobility is the only domain that is significantly affected in the people with HH. CONCLUSION: Identification of the significant areas of visual difficulties and their effects on quality of life is important as it can help better address the patients' rehabilitation needs. The current study identifies the need for orientation and mobility training as well as independent living rehabilitation in patients with HH to help address the difficulties in their vision-specific quality of life and maximize their residual vision.

Role of junctional adhesion molecule-like protein in mediating monocyte transendothelial migration.

OBJECTIVE: Monocyte migration across the vascular endothelium of blood vessels is a key early event in atherosclerosis. The mechanisms underlying monocyte transendothelial migration (TEM), however, are still not completely understood. Here we studied the role of junctional adhesion molecule-like protein (JAML) in regulating monocyte TEM. METHODS AND RESULTS: Firstly, by Western blot and flow cytometry, we showed that JAML was strongly expressed in monocytes and monocyte surface expression of JAML was upregulated by monocyte chemotaxis protein-1 stimulation. Both monocyte adhesion to and migration across tumor necrosis factor-alpha (TNFalpha) preactivated human microvascular endothelial cell (HMEC-1) monolayers were dose-dependently reduced by anti-JAML antiserum or soluble extracellular JAML recombinant. Secondly, short-term exposure of human monocytes and THP-1 cells to advanced glycation end products increased cell surface JAML expression, which was correlated with enhanced cell adhesion and TEM. In contrast, knockdown of JAML in THP-1 monocytes decreased both adhesion and transmigration of THP-1 monocytes. Finally, direct binding assay of the soluble JAML to HMEC-1 monolayers suggested that endothelial coxsackie and adenovirus receptor (CAR) may serve as one of the ligands for JAML. CONCLUSIONS: Monocytic JAML plays a critical role in regulating monocyte TEM probably via binding to the endothelial CAR and other tight junction-associated adhesive molecules.

The heparan sulfate proteoglycan form of epithelial CD44v3 serves as a CD11b/CD18 counter-receptor during polymorphonuclear leukocyte transepithelial migration.

Leukocyte beta2-integrin CD11b/CD18 mediates the firm adhesion and subsequent transepithelial migration of polymorphonuclear leukocytes, but the identity of its counter-receptor(s) on epithelia remains elusive. Here we identified a monoclonal antibody, clone C3H7, which strongly bound to the basolateral membranes of epithelial cells and inhibited both the adhesion of epithelial cells to immobilized CD11b/CD8 and the transepithelial migration of PMNs in a physiologically relevant basolateral-to-apical direction. C3H7 antigen expression in epithelial monolayers was significantly increased by treatment with proinflammatory cytokine interferon-gamma or a combination of interferon-gamma and tumor necrosis factor-alpha. Up-regulation of C3H7 antigen was also observed in the epithelium of inflamed human colon tissues. Microsequencing and Western blotting of the purified antigen showed it to be CD44 variant 3 (CD44v3), a approximately 160-kDa membrane glycoprotein. Further studies demonstrated that this epithelial CD44v3 specifically binds to CD11b/CD18 through its heparan sulfate moieties. In summary, our study demonstrates for the first time that the heparan sulfate proteoglycan form of epithelial CD44v3 plays a critical role in facilitating PMN recruitment during inflammatory episodes via directly binding to CD11b/CD18.

Third cranial nerve palsy caused by intracranial extension of a sino-orbital natural killer T-cell lymphoma.

Natural killer/T-cell lymphomas (NKTLs) are rare destructive lesions that usually involve the nasal cavity or paranasal sinuses. Orbital and intracranial involvement is rare. A 53-year-old man with systemic lupus erythematosus who was receiving chronic low-dose prednisone treatment developed proptosis of the right eye. Biopsy of a sino-orbital lesion suggested nonspecific inflammation. Clinical and imaging manifestations resolved with a higher dose of prednisone, but when the prednisone dose was tapered, the patient developed a complete right third cranial nerve palsy. Imaging showed return of the original lesion, now with intracranial extension and enhancement of the right third cranial nerve. Repeat biopsy showed features consistent with NKTL. Biopsy of this lesion in its early stage may misleadingly suggest a primary inflammatory disorder because of a paucity of neoplastic cells, a large number of inflammatory cells recruited by the innate natural killer (NK) cell immune response, and extensive necrosis caused by angiodestructive tumor cells.

Gene response profiles for Daphnia pulex exposed to the environmental stressor cadmium reveals novel crustacean metallothioneins.

BACKGROUND: Genomic research tools such as microarrays are proving to be important resources to study the complex regulation of genes that respond to environmental perturbations. A first generation cDNA microarray was developed for the environmental indicator species Daphnia pulex, to identify genes whose regulation is modulated following exposure to the metal stressor cadmium. Our experiments revealed interesting changes in gene transcription that suggest their biological roles and their potentially toxicological features in responding to this important environmental contaminant. RESULTS: Our microarray identified genes reported in the literature to be regulated in response to cadmium exposure, suggested functional attributes for genes that share no sequence similarity to proteins in the public databases, and pointed to genes that are likely members of expanded gene families in the Daphnia genome. Genes identified on the microarray also were associated with cadmium induced phenotypes and population-level outcomes that we experimentally determined. A subset of genes regulated in response to cadmium exposure was independently validated using quantitative-realtime (Q-RT)-PCR. These microarray studies led to the discovery of three genes coding for the metal detoxication protein metallothionein (MT). The gene structures and predicted translated sequences of D. pulex MTs clearly place them in this gene family. Yet, they share little homology with previously characterized MTs. CONCLUSION: The genomic information obtained from this study represents an important first step in characterizing microarray patterns that may be diagnostic to specific environmental contaminants and give insights into their toxicological mechanisms, while also providing a practical tool for evolutionary, ecological, and toxicological functional gene discovery studies. Advances in Daphnia genomics will enable the further development of this species as a model organism for the environmental sciences.

Double vision in a patient with thyroid disease: what's the big deal?

A 70-year-old woman with a 46-year history of Graves disease had significant thyroid related orbitopathy (TRO) requiring previous bilateral orbital decompressions and one previous strabismus procedure for an exotropia of 60 PD. At the initial neuro-ophthalmology assessment, she had an exotropia of 20 PD and was scheduled for further surgery, but at the time of a second assessment a few weeks later, her strabismus had markedly changed. Accordingly, the patient underwent a neostigmine bromide test that demonstrated evidence of co-existing myasthenia gravis.

Receptor for advanced glycation endproducts mediates neutrophil migration across intestinal epithelium.

Receptor for advanced glycation endproducts (RAGE) is an Ig superfamily cell surface receptor that interacts with a diverse array of ligands associated with inflammatory responses. In this study, we provide evidence demonstrating that RAGE is involved in inflammatory responses in the intestines. We showed that RAGE is expressed in intestinal epithelial cells, primarily concentrated at the lateral membranes close to the apical cell junction complexes. Although RAGE expression was low in epithelium under normal conditions, this protein was up-regulated after treatment with the inflammatory cytokines IFN-gamma and/or TNF-alpha. RAGE expression was also elevated in colon tissue samples from patients with inflammatory bowel diseases. Using in vitro transmigration assays, we found that RAGE mediates neutrophil (polymorphonuclear leukocytes (PMN)) adhesion to, and subsequent migration across, intestinal epithelial monolayers. This activity appears to be mediated by the binding of RAGE to the PMN-specific beta(2) integrin CD11b/CD18. Thus, these results provide a novel mechanism for the regulation of PMN transepithelial migration and may suggest a new therapeutic target for intestinal inflammation.

Functional elements on SIRPalpha IgV domain mediate cell surface binding to CD47.

SIRPalpha and SIRPbeta1, the two major isoforms of the signal regulatory protein (SIRP) family, are co-expressed in human leukocytes but mediate distinct extracellular binding interactions and divergent cell signaling responses. Previous studies have demonstrated that binding of SIRPalpha with CD47, another important cell surface molecule, through the extracellular IgV domain regulates important leukocyte functions including macrophage recognition, leukocyte adhesion and transmigration. Although SIRPbeta1 shares highly homologous extracellular IgV structure with SIRPalpha, it does not bind to CD47. Here, we defined key amino acid residues exclusively expressing in the IgV domain of SIRPalpha, but not SIRPbeta1, which determine the extracellular binding interaction of SIRPalpha to CD47. These key residues include Gln67, a small hydrophobic amino acid (Ala or Val) at the 57th position and Met102. We found that Gln67 and Ala/Val57 are critical. Mutation of either of these residues abates SIRPalpha directly binding to CD47. Functional cell adhesion and leukocyte transmigration assays further demonstrated central roles of Gln67 and Ala/Val57 in SIRPalpha extracellular binding mediated cell interactions and cell migration. Another SIRPalpha-specific residue, Met102, appears to assist SIRPalpha IgV binding through Gln67 and Ala/Val57. An essential role of these amino acid residues in SIRPalpha binding to CD47 was further confirmed by introducing these residues into the SIRPbeta1 IgV domain, which dramatically converts SIRPbeta1 into a CD47-binding molecule. Our results thus revealed the molecular basis by which SIRPalpha binds to CD47 and shed new light into the structural mechanisms of SIRP isoform mediated distinctive extracellular interactions and cellular responses.