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1.
Mar Pollut Bull ; 166: 112183, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33647846

RESUMO

Southeast Alaska sea otters (Enhydra lutris) have had a rapid rise in their population. As they feed primarily on sessile prey, they are excellent sentinels for examining metals contamination. Objectives of this study on sea otters were to determine: (1) concentrations of metals in different tissues; (2) whether metals biomagnify from stomach contents (i.e., the prey) to other tissues; (3) whether selenium and mercury concentrations indicate an overall health benefit or risk; and (4) if metals concentrations in tissues vary with body size. Brain, kidney, gonad, liver, and stomach contents were collected from freshly harvested sea otters in Icy Strait, Alaska, and analyzed for arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), total mercury (THg), and selenium (Se). Metals concentrations varied significantly, and some were biomagnified, with livers and kidneys harboring the highest concentrations. Lead and arsenic appeared to be readily excreted. This study represents baseline metals concentrations to assist in monitoring the health of sea otters.


Assuntos
Lontras , Alaska , Animais , Encéfalo , Conteúdo Gastrointestinal , Gônadas , Rim , Fígado
2.
Sci Total Environ ; 736: 139676, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32497892

RESUMO

On average, Alaskans in rural communities consume over three times the Federally recommended maximum weekly fish ingestion rate (IR), the overwhelming majority of which is Pacific salmon. Results of statewide monitoring efforts consistently show that Pacific salmon from Alaska have low concentrations of mercury, yet concerns regarding dietary exposure to methylmercury (MeHg) and other aquatic contaminants continue to contribute to declining subsistence fish consumption rates in rural communities. Therefore, the goal of the present study was to use statewide biomonitoring datasets and regional fish IRs to quantitatively evaluate potential risk from dietary MeHg exposure via subsistence consumption of salmon from Alaska. Hazard Indices (HIs) did not exceed 1 for any of the groups evaluated, indicating negligible risk for the average Alaskan subsistence consumer. Selenium health benefit values (HBVSe) of various fish species from AK were also calculated, with positive results for all commonly consumed subsistence species. Additionally, mercury concentrations in the hair of Alaskan women were evaluated as a proxy for dietary MeHg exposure. Results reveal that Alaskan women of childbearing age have substantially lower hair Hg concentrations than their counterparts in other large-scale biomonitoring studies, despite similar fish IRs. Collectively, results of the present study suggest that MeHg in Pacific salmon does not pose an unacceptable hazard for the average subsistence consumer in Alaska.


Assuntos
Mercúrio/análise , Compostos de Metilmercúrio/análise , Alaska , Animais , Disponibilidade Biológica , Monitoramento Ambiental , Feminino , Peixes , Contaminação de Alimentos/análise , Humanos , População Rural
3.
Environ Pollut ; 251: 390-399, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31100570

RESUMO

Perchlorate is a pervasive, water-soluble contaminant that competitively inhibits the sodium/iodide symporter, reducing the available iodide for thyroid hormone synthesis. Insufficient iodide uptake can lead to hypothyroidism and metabolic syndromes. Because metabolism, obesity and non-alcoholic fatty liver disease (NAFLD) are tightly linked, we hypothesized that perchlorate would act as an obesogen and cause NAFLD via accumulation of lipids in liver of developing threespine stickleback (Gasterosteus aculeatus). We performed an upshift/downshift exposure regime (clean water to perchlorate treated water or perchlorate treated water to clean water) on stickleback embryos at two concentrations (30 mg/L and 100 mg/L) plus the control (0 mg/L) over the course of 305 days. Adult stickleback were euthanized, H&E stained and analyzed for liver morphology. Specifically, we counted the number of lipid droplets, and measured the area of each droplet and the total lipid area of a representative section of liver. We found that perchlorate treated fish had more and larger lipid droplets, and a larger percentage of lipid in their liver than control fish. These data indicate that perchlorate causes NAFLD and hepatic steatosis in stickleback at concentrations commonly found at contaminated sites. These data also indicate the potential of perchlorate to act as an obesogen. Future studies should investigate the obesogenic capacity of perchlorate by examining organ specific lipid accumulation and whether perchlorate induces these effects at concentrations commonly found in drinking water. Work is also needed to determine the mechanisms by which perchlorate induces lipid accumulation.


Assuntos
Exposição Ambiental/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Percloratos/toxicidade , Smegmamorpha/metabolismo , Compostos de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Feminino , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Smegmamorpha/crescimento & desenvolvimento
4.
Allergy ; 73(6): 1322-1330, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29318637

RESUMO

BACKGROUND: Preventive measures to decrease the frequency and intensity of anaphylactic events are essential to provide optimal care for allergic patients. Aggravating factors may trigger or increase the severity of anaphylaxis and therefore need to be recognized and avoided. OBJECTIVE: To identify and prioritize factors associated with an increased risk of developing severe anaphylaxis. METHODS: Data from the Anaphylaxis Registry (122 centers in 11 European countries) were used in logistic regression models considering existing severity grading systems, elicitors, and symptoms to identify the relative risk of factors on the severity of anaphylaxis. RESULTS: We identified higher age and concomitant mastocytosis (OR: 3.1, CI: 2.6-3.7) as the most important predictors for an increased risk of severe anaphylaxis. Vigorous physical exercise (OR: 1.5, CI: 1.3-1.7), male sex (OR: 1.2, CI: 1.1-1.3), and psychological burden (OR: 1.4, CI: 1.2-1.6) were more often associated with severe reactions. Additionally, intake of beta-blockers (OR: 1.9, CI: 1.5-2.2) and ACE-I (OR: 1.28, CI: 1.05, 1.51) in temporal proximity to allergen exposition was identified as an important factor in logistic regression analysis. CONCLUSION: Our data suggest it may be possible to identify patients who require intensified preventive measures due to their relatively higher risk for severe anaphylaxis by considering endogenous and exogenous factors.


Assuntos
Anafilaxia/epidemiologia , Fatores Etários , Alérgenos/imunologia , Anafilaxia/diagnóstico , Comorbidade , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Mastocitose , Vigilância em Saúde Pública , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais
5.
Gen Comp Endocrinol ; 219: 24-35, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25865142

RESUMO

Perchlorate, a common aquatic contaminant, is well known to disrupt homeostasis of the hypothalamus-pituitary-thyroid axis. This study utilizes the threespine stickleback (Gasterosteus aculeatus) fish to determine if perchlorate exposure during certain windows of development has morphological effects on thyroid and gonads. Fish were moved from untreated water to perchlorate-contaminated water (30 and 100mg/L) starting at 0, 3, 7, 14, 21, 42, 154 and 305 days post fertilization until approximately one year old. A reciprocal treatment (fish in contaminated water switched to untreated water) was conducted on the same schedule. Perchlorate exposure increased angiogenesis and follicle proliferation in thyroid tissue, delayed gonadal maturity, and skewed sex ratios toward males; effects depended on concentration and timing of exposure. This study demonstrates that perchlorate exposure beginning during the first 42 days of development has profound effects on stickleback reproductive and thyroid tissues, and by implication can impact population dynamics. Long-term exposure studies that assess contaminant effects at various stages of development provide novel information to characterize risk to aquatic organisms, to facilitate management of resources, and to determine sensitive developmental windows for further study of underlying mechanisms.


Assuntos
Gônadas/crescimento & desenvolvimento , Percloratos/metabolismo , Smegmamorpha/genética , Smegmamorpha/metabolismo , Compostos de Sódio/metabolismo , Glândula Tireoide/metabolismo , Animais , Proliferação de Células , Feminino , Masculino , Reprodução , Maturidade Sexual , Poluentes Químicos da Água
6.
Gen Comp Endocrinol ; 219: 36-44, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25753171

RESUMO

Adequate levels of thyroid hormone are critical during development and metamorphosis, and for maintaining metabolic homeostasis. Perchlorate, a common contaminant of water sources, inhibits thyroid function in vertebrates. We utilized threespine stickleback (Gasterosteus aculeatus) to determine if timing of perchlorate exposure during development impacts adult dermal skeletal phenotypes. Fish were exposed to water contaminated with perchlorate (30mg/L or 100mg/L) beginning at 0, 3, 7, 14, 21, 42, 154 or 305days post fertilization until sexual maturity at 1year of age. A reciprocal treatment moved stickleback from contaminated to clean water on the same schedule providing for different stages of initial exposure and different treatment durations. Perchlorate exposure caused concentration-dependent significant differences in growth for some bony traits. Continuous exposure initiated within the first 21days post fertilization had the greatest effects on skeletal traits. Exposure to perchlorate at this early stage can result in small traits or abnormal skeletal morphology of adult fish which could affect predator avoidance and survival.


Assuntos
Percloratos/metabolismo , Smegmamorpha/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Smegmamorpha/genética , Poluentes Químicos da Água
7.
Allergy ; 69(10): 1397-404, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24989080

RESUMO

BACKGROUND: Occurrence, elicitors and treatment of severe allergic reactions are recognized and reported differently between countries. We aimed to collect standardized data throughout Europe on anaphylaxis referred for diagnosis and counselling. METHODS: Tertiary allergy, dermatology and paediatric units in 10 European countries took part in this pilot phase of the first European Anaphylaxis Registry, from June 2011 to March 2014. An online questionnaire was used to collect data on severe allergic reactions based on the medical history and diagnostics. RESULTS: Fifty-nine centres reported 3333 cases of anaphylaxis, with 26.7% below 18 years of age. Allergic reactions were mainly caused by food (children and adults 64.9% and 20.2%, respectively) and insect venom (20.2% and 48.2%) and less often by drugs (4.8% and 22.4%). Most reactions occurred within 30 min of exposure (80.5%); a delay of 4+ hours was mainly seen in drug anaphylaxis (6.7%). Symptom patterns differed by elicitor, with the skin being affected most often (84.1%). A previous, usually milder reaction to the same allergen was reported by 34.2%. The mainstay of first-line treatment by professionals included corticoids (60.4%) and antihistamines (52.8%). Only 13.7% of lay- or self-treated reactions to food and 27.6% of insect anaphylaxis received on-site adrenaline. CONCLUSION: This pilot phase of a pan-European registry for severe allergic reactions provides for the first time data on anaphylaxis throughout Europe, demonstrates its potential functionality and allows a comparison of symptom patterns, elicitors and treatment habits between referral centres and countries.


Assuntos
Anafilaxia/epidemiologia , Anafilaxia/terapia , Sistema de Registros , Adulto , Criança , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Projetos Piloto
8.
J Toxicol Environ Health A ; 76(18): 1072-84, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24188192

RESUMO

This study examined effects of varying concentrations of the environmental contaminant perchlorate in northern pike (Esox lucius) based on exposure in water and/or from prey (threespine stickleback, Gasterosteus aculeatus). Routes of exposure to pike were through contaminated water at 0, 10, or 100 mg/L perchlorate for 49 d and/or through feeding, 1 per day over 14 d, sticklebacks that were previously maintained in water at 0, 10, or 100 mg/L perchlorate. Both water and food significantly contributed to pike tissue concentrations of perchlorate as compared to controls, but, as expected for a water-soluble contaminant, perchlorate did not biomagnify from prey to predatory fish. Pike gastrointestinal tissue retained significantly more perchlorate than other tissues combined. Route of exposure and concentration of perchlorate in various media are important to consider in risk assessment when evaluating uptake and tissue concentration of perchlorate because significantly higher tissue concentrations may result from combined prey and water exposures than from prey or water exposures alone in a concentration-dependent manner.


Assuntos
Esocidae/fisiologia , Cadeia Alimentar , Percloratos/metabolismo , Smegmamorpha/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Relação Dose-Resposta a Droga , Percloratos/química , Comportamento Predatório
9.
Evolution ; 66(10): 3277-86, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23025615

RESUMO

We used no-choice mating trials to test for assortative mating between a newly derived resident-freshwater population (8-22 generations since founding) of threespine stickleback (Gasterosteus aculeatus) in Loberg Lake, Alaska and its putative anadromous ancestor as well as a morphologically convergent but distantly related resident-freshwater population. Partial reproductive isolation has evolved between the Loberg Lake population and its ancestor within a remarkably short time period. However, Loberg stickleback readily mate with morphologically similar, but distantly related resident-freshwater stickleback. Partial premating isolation is asymmetrical; anadromous females and smaller resident-freshwater males from Loberg Lake readily mate, but the anadromous males and smaller Loberg females do not. Our results indicate that premating isolation can begin to evolve in allopatry within a few generations after isolation as a correlated effect of evolution of reduced body size.


Assuntos
Preferência de Acasalamento Animal , Isolamento Reprodutivo , Smegmamorpha , Adaptação Biológica , Animais , Feminino , Especiação Genética , Masculino
10.
Blut ; 38(1): 35-45, 1979 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-281972

RESUMO

Human normal and granulocytic leukemic progenitor cells produce colonies and clusters when cultured in the plasma clot system in vitro. The number of colonies formed and their cellular composition was comparable to that reported for the system (soft agar) usually used for these studies. The plasma clot system has the advantage of permitting in situ morphologic and cytochemical characterizaion of the cells within the colonies. A comparison was also made of the growth of leukemic cells in suspension cultures placed within conventional and modified Marbrook flasks. These studies demonstrated no advantage for the Marbrook system in cultures incubated for up to 7 days.


Assuntos
Técnicas de Cultura/métodos , Leucemia Mieloide Aguda/patologia , Humanos , Plasma , Fatores de Tempo
11.
Cell Differ ; 7(1-2): 1-10, 1978 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-566165

RESUMO

Friend leukemia cells were cultured in vitro in the presence or absence of agents which induce erythroid differentiation. The cultures were harvested and the degree of differentiation determined. Clonogenicity of the cells in vitro and malignancy in vivo were determined as well. There was an inverse exponential relationship between the degree of differentiation and the clonogenicity of the culture. Differentiation was also associated with a modest decline in malignancy. Of interest was the observation that bromodeoxyuridine inhibited the biochemical manifestations of erythroid differentiation, but did not prevent the decline in clonogenicity which accompanied differentiation.


Assuntos
Leucemia Experimental/fisiopatologia , Animais , Diferenciação Celular , Células Clonais , Dimetil Sulfóxido , Feminino , Vírus da Leucemia Murina de Friend , Humanos , Camundongos
12.
Blood ; 47(3): 363-8, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1062223

RESUMO

The ability of families of compounds with known and potential cryoprotective properties to induce the differentiation of Friend leukemia cells in vitro was studied. For each agent, both the proportion of differentiated cells in the culture and the total amount of heme/10(7) cells were determined. Within each family of compounds there was a direct correlation between a compound's cryoprotective ability, its ability to donate electron pairs for hydrogen bonding (basicity), and its ability to induce differentiation. While individual agents differed with respect to the proportion of cells which were induced to differentiate, the biology of the process of differentiation appeared to be similar, regardless of the agent used. A cell line which was unresponsive to DMSO was responsive to other inducers, suggesting that this DMSO-resistant cell line differed from its parent DMSO-responsive cell line either in its metabolism of the inducers or in the ability of the inducers to enter the cell. Alternatively, there may be more than one mechanism involved in the chemical induction of differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Leucemia Eritroblástica Aguda/patologia , Acetamidas/farmacologia , Animais , Linhagem Celular , Heme/biossíntese , Leucemia Experimental/patologia , Ureia/farmacologia
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