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1.
Int J Mol Sci ; 25(11)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38892364

ABSTRACT

This report describes major pathomechanisms of disease in which the dysregulation of host inflammatory processes is a major factor, with cardiovascular disease (CVD) as a primary model, and reviews strategies for countermeasures based on synergistic interaction between various agents, including drugs and generally regarded as safe (GRAS) natural medical material (NMM), such as Ginkgo biloba, spice phytochemicals, and fruit seed flavonoids. The 15 well-defined CVD classes are explored with particular emphasis on the extent to which oxidative stressors and associated ischemia-reperfusion tissue injury contribute to major symptoms. The four major categories of pharmaceutical agents used for the prevention of and therapy for CVD: statins, beta blockers (ß-blockers), blood thinners (anticoagulants), and aspirin, are presented along with their adverse effects. Analyses of major cellular and molecular features of drug- and NMM-mediated cardioprotective processes are provided in the context of their development for human clinical application. Future directions of the evolving research described here will be particularly focused on the characterization and manipulation of calcium- and calcineurin-mediated cascades of signaling from cell surface receptors on cardiovascular and immune cells to the nucleus, with the emergence of both protective and pathological epigenetic features that may be modulated by synergistically-acting combinations of drugs and phytochemicals in which phytochemicals interact with cells to promote signaling that reduces the effective dosage and thus (often) toxicity of drugs.


Subject(s)
Cardiovascular Diseases , Phytochemicals , Humans , Phytochemicals/therapeutic use , Phytochemicals/pharmacology , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/prevention & control , Cardiovascular Diseases/metabolism , Animals
2.
Otolaryngol Clin North Am ; 56(4): 727-739, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37268516

ABSTRACT

Anterior skull base reconstruction requires careful preoperative planning to use the most effective technique for the expected defect. Adherence to the principles of skull base reconstruction is imperative to minimize complications and improve patient outcomes.


Subject(s)
Plastic Surgery Procedures , Skull Base Neoplasms , Humans , Surgical Flaps/surgery , Skull Base/surgery , Skull Base Neoplasms/surgery , Retrospective Studies , Cerebrospinal Fluid Leak/surgery
3.
Pharmacol Res Perspect ; 11(3): e01091, 2023 06.
Article in English | MEDLINE | ID: mdl-37190667

ABSTRACT

Previous investigations have demonstrated that treatment of animals with rapamycin increases levels of autophagy, which is a process by which cells degrade intracellular detritus, thus suppressing the emergence of senescent cells, whose pro-inflammatory properties, are primary drivers of age-associated physical decline. A hypothesis is tested here that rapamycin treatment of mice approaching the end of their normal lifespan exhibits increased survival, enhanced expression of autophagic proteins; and klotho protein-a biomarker of aging that affects whole organism senescence, and systemic suppression of inflammatory mediator production. Test groups of 24-month-old C57BL mice were injected intraperitoneally with either 1.5 mg/kg/week rapamycin or vehicle. All mice administered rapamycin survived the 12-week course, whereas 43% of the controls died. Relative to controls, rapamycin-treated mice experienced minor but significant weight loss; moreover, nonsignificant trends toward decreased levels of leptin, IL-6, IL-1ß, TNF-α, IL-1α, and IGF-1, along with slight elevations in VEGF, MCP-1 were observed in the blood serum of rapamycin-treated mice. Rapamycin-treated mice exhibited significantly enhanced autophagy and elevated expression of klotho protein, particularly in the kidney. Rapamycin treatment also increased cardiomyocyte Ca2+ -sensitivity and enhanced the rate constant of force re-development, which may also contribute to the enhanced survival rate in elderly mice.


Subject(s)
Klotho Proteins , Sirolimus , Mice , Animals , Sirolimus/pharmacology , Mice, Inbred C57BL , Aging , Biomarkers , Autophagy
4.
Ann Otol Rhinol Laryngol ; 131(1): 94-100, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33880969

ABSTRACT

OBJECTIVE: Complications associated with intracranial vault compromise can be neurologically and systemically devastating. Primary and secondary repair of these deficits require an air and watertight barrier between the intracranial and extracranial environments. This study evaluated the outcomes and utility of using intracranial free tissue transfer as both primary and salvage surgical repair of reconstruction. METHODS: A retrospective review was performed of all subjects who underwent intracranial free tissue transfer as primary or salvage repair. RESULTS: A total of 13 intracranial free tissue transfers were performed on 11 subjects: osteocutaneous radial forearm free flaps (n = 6), partial myofascial rectus abdominis flaps (n = 5), temporoparietal fascia flap (n = 1), and serratus anterior myofascial flap (n = 1). Primary reconstruction was performed on 4 subjects with the remaining being salvage repair. Indications for surgery included neoplasm (n = 6 of 11), ballistic trauma (n = 3 of 11), motor vehicle accident (n = 1 of 11), and infection (n = 1 of 11). Three subjects required additional surgical repair for CSF leak and pneumocephalus, with 2 subjects requiring an additional free tissue transfer at a different site. CONCLUSION: In our experience, free tissue transfer is an effective primary and salvage surgical technique in the reconstruction of complex intracranial problems.


Subject(s)
Free Tissue Flaps , Plastic Surgery Procedures/methods , Skull Base/surgery , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Young Adult
5.
Environ Monit Assess ; 193(10): 636, 2021 Sep 08.
Article in English | MEDLINE | ID: mdl-34498140

ABSTRACT

Some wetlands in the northern Great Plains support hundreds to thousands of late-stage tadpoles providing important sources of recruitment to the Wood Frog (Lithobates sylvaticus) population while many other wetlands produce none. Relationships between water quality and late-stage tadpole abundance were determined to identify the water quality parameters associated with tadpole abundance. Water samples were collected, and late-stage tadpole abundances were assessed once each year in late June for 12 years in 26 wetlands. Catch or abundance was the number of tadpoles captured in 30 min with a dip-net. The catch of tadpoles was variable both among wetlands and over the long-term for individual wetlands, and ranged from 0 to several hundred individuals. Wood Frog tadpoles were especially sensitive to sodium and chloride concentrations. At Cl concentrations less than 5 mg/L, occupancy for late-stage tadpoles was 84%, and declined by about 8% for each 5 mg/L increase in Cl to 40.1 mg/L Cl, the maximum concentration associated with the detection of tadpoles. Optimal water quality for late-stage Wood Frog tadpoles included low concentrations of Na [Formula: see text] = 8.1 mg/L), and Cl [Formula: see text] = 4.2 mg/L) relative to total dissolved solids and other ions, and high concentrations of phosphorus. In a landscape where ion concentrations in wetlands can range over 3 orders of magnitude, water quality analyses suggest that abundant Wood Frog tadpole populations occur in wetlands dominated by snow-melt runoff with its characteristic low ion concentrations. The present study highlights the importance to amphibian conservation of the water quality environment of tadpole habitat.


Subject(s)
Environmental Monitoring , Water Quality , Animals , Humans , Larva , Ranidae , Wetlands
6.
Int J Mol Sci ; 21(24)2020 Dec 18.
Article in English | MEDLINE | ID: mdl-33353225

ABSTRACT

The class of tetrapyrrol "coordination complexes" called hemes are prosthetic group components of metalloproteins including hemoglobin, which provide functionality to these physiologically essential macromolecules by reversibly binding diatomic gasses, notably O2, which complexes to ferrous (reduced/Fe(II)) iron within the heme porphyrin ring of hemoglobin in a pH- and PCO2-dependent manner-thus allowing their transport and delivery to anatomic sites of their function. Here, pathologies associated with aberrant heme degradation are explored in the context of their underlying mechanisms and emerging medical countermeasures developed using heme oxygenase (HO), its major degradative enzyme and bioactive metabolites produced by HO activity. Tissue deposits of heme accumulate as a result of the removal of senescent or damaged erythrocytes from circulation by splenic macrophages, which destroy the cells and internal proteins, including hemoglobin, leaving free heme to accumulate, posing a significant toxicogenic challenge. In humans, HO uses NADPH as a reducing agent, along with molecular oxygen, to degrade heme into carbon monoxide (CO), free ferrous iron (FeII), which is sequestered by ferritin protein, and biliverdin, subsequently metabolized to bilirubin, a potent inhibitor of oxidative stress-mediated tissue damage. CO acts as a cellular messenger and augments vasodilation. Nevertheless, disease- or trauma-associated oxidative stressors sufficiently intense to overwhelm HO may trigger or exacerbate a wide range of diseases, including cardiovascular and neurologic syndromes. Here, strategies are described for counteracting the effects of aberrant heme degradation, with a particular focus on "bioflavonoids" as HO inducers, shown to cause amelioration of severe inflammatory diseases.


Subject(s)
Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/physiopathology , Flavonoids/pharmacology , Heme/metabolism , Inflammation/drug therapy , Inflammation/physiopathology , Nervous System Diseases/drug therapy , Nervous System Diseases/physiopathology , Animals , Heme Oxygenase-1/metabolism , Humans
7.
J Environ Qual ; 47(6): 1554-1565, 2018 11.
Article in English | MEDLINE | ID: mdl-30512057

ABSTRACT

Wetlands are abundant throughout the agricultural landscape of central Saskatchewan, Canada, and the biota present in these wetlands may be vulnerable to the toxic effects of pesticides used on nearby crops. We hypothesized that herbicide concentrations would be higher in wetlands on minimum-tillage farms than on organic (no herbicide use) farms, and that the principal transport mechanisms of runoff versus atmospheric deposition could be identified based on the concentrations in these two wetland types. To test these hypotheses, 29 herbicides were monitored for 5 yr in 16 wetlands on minimum-tillage farms and in seven wetlands on organic farms. Twenty herbicides were detected in wetlands on minimum-tillage farms versus 12 in wetlands on organic farms. Clopyralid, MCPA, 2,4-D, bromoxynil, dichlorprop, and dicamba were detected at a >50% frequency in wetlands on both minimum-tillage and organic farms. Concentrations of clopyralid were significantly higher in wetlands on minimum-tillage farms than in those on organic farms, whereas no significant difference was observed for any of the other five herbicides. Glyphosate, including its degradation product AMPA, was detected in >50% frequency only in wetlands on minimum-tillage farms where the mean concentration (1278 ng L) was higher than the concentration of other herbicides. Mass applied, vapor pressure, and water solubility were important determinants of herbicide concentrations and detections in wetlands. Herbicide concentrations in all but two samples were less than their respective Canadian guideline for protection of aquatic life, suggesting that, overall, individual herbicide concentrations in the wetlands were not toxic to biota.


Subject(s)
Agriculture , Environmental Monitoring , Herbicides/analysis , Soil Pollutants/analysis , Wetlands , Canada , Farms
8.
Environ Monit Assess ; 188(10): 582, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27663874

ABSTRACT

At high concentrations, mercury (Hg) is toxic to vertebrates, causing neurological, behavioral, and teratological dysfunction. Selenium (Se) not only is an essential element but also has a high affinity for Hg, binding to organic methyl mercury at a molar ratio of Se/Hg of 1:1. Ratios of <1 increase risk of Hg toxicity. For gravid fish, low concentrations of Se in ova could increase potential for Hg toxicity, compromising embryonic development and fitness of fry. Mercury and selenium concentrations and ratios were investigated in the muscle and ovaries of six species from five families of fish to assess potential for risk to ecological fitness. Molar ratios of Se/Hg in muscle were typically >18 for lower trophic level species but ≤2 for piscivores. For all species combined, the concentrations of Hg in ova were significantly related to concentrations of Hg in muscle. Concentrations of Se in ova versus muscle showed a similar significant relationship that was independent of muscle Hg concentration. Mean ova molar Se/Hg ratios were high, ranging from 69 to 955 for the 6 species. However, a declining relationship between the ova Se/Hg molar ratio and the muscle concentration of Hg for all species combined suggests that development of ova and fry might be compromised for those piscivores with the highest muscle Hg concentrations because of Hg-related Se deficiency.


Subject(s)
Fishes , Mercury/analysis , Muscles/chemistry , Ovary/chemistry , Selenium/analysis , Water Pollutants, Chemical/analysis , Animals , Environmental Monitoring , Female , Male , Saskatchewan
9.
J Environ Qual ; 44(6): 1948-55, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26641347

ABSTRACT

Sulfonylurea herbicides are applied at relatively low rates (3-40 g ha) to control weeds in a variety of crops grown in the prairie pothole region of south-central Canada. Because of their high phytotoxicity and the likelihood of their transport in surface runoff, there is concern about impacts of sulfonylurea herbicides to wetland ecosystems embedded in agricultural landscapes. In a previous study, dissipation half-lives (DT values) were determined for three sulfonylurea herbicides (thifensulfuron-methyl, ethametsulfuron-methyl, and metsulfuron-methyl), each possessing a hydrolyzable methyl ester linkage. In the current study, persistence of three sulfonylurea herbicides without a methyl ester linkage was determined in prairie farm dugouts (ponds). The dugouts were fortified with environmentally relevant concentrations (3.3-6.5 µg L) of either sulfosulfuron, rimsulfuron, or nicosulfuron. The order of persistence of these herbicides in dugout water from May and June to November and December was nicosulfuron > sulfosulfuron > rimsulfuron, with DT values of 75, 44, and 10 d, respectively. The lack of a methyl ester linkage in these herbicides did not significantly affect their overall persistence relative to those with the ester linkage. In all three dugouts, the decrease in herbicide mass in the water column from water loss via hydrological discharge to groundwater was minimal. The relatively long persistence of these herbicides in the water column of the dugouts reflects the stability of the sulfonylurea linkage to hydrolysis in weakly alkaline waters and indicates not only that microbial and photolytic degradation were low but also that there was little partitioning into sediments.

10.
Environ Toxicol Chem ; 34(12): 2846-55, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26113505

ABSTRACT

Mercury bioaccumulation models developed for fish provide insight into the sources and transfer of Hg within ecosystems. Mercury concentrations were assessed for 16 fish species of the western reach of Lake Diefenbaker, Saskatchewan, Canada. For top predators (northern pike, Esox Lucius; walleye, Sander vitreum), Hg concentrations were positively correlated to δ(15)N, and δ(15)N to fish age, suggesting that throughout life these fish fed on organisms with increasingly higher trophic values and Hg concentrations. However, fish mass and/or age were the principal parameters related to Hg concentrations for most species. For 9 common species combined, individual variation in Hg concentration was explained in declining order of importance by fish mass, trophic position (δ(15)N), and fish age. Delta (15)N value was not the leading variable related to Hg concentration for the assemblage, probably because of the longevity of lower--trophic-level species (3 species ≥ 20 yr), substantial overlap in Hg concentration and δ(15)N values for large-bodied fish up to 3000 g, and complex relationships between Hg concentration and δ(15)N among species. These results suggest that the quantity of food (and Hg) consumed each year and converted to fish mass, the quantity of Hg bioaccumulated over years and decades, and trophic position were significant determinants of Hg concentration in Lake Diefenbaker fish.


Subject(s)
Lakes/chemistry , Mercury/pharmacokinetics , Models, Biological , Perches/metabolism , Water Pollutants, Chemical/pharmacokinetics , Animals , Ecosystem , Mercury/analysis , Saskatchewan , Species Specificity , Water Pollutants, Chemical/analysis
11.
Bioorg Med Chem Lett ; 23(23): 6248-53, 2013 Dec 01.
Article in English | MEDLINE | ID: mdl-24144851

ABSTRACT

A novel series of muscarinic receptor antagonists was developed, with the aim of identifying a compound with high M3 receptor potency and a reduced risk of dose-limiting side effects with potential for the treatment of COPD. Initial compound modifications led to a novel cycloheptyl series, which was improved by focusing on a quinuclidine sub-series. A wide range of N-substituents was evaluated to determine the optimal substituent providing a high M3 receptor potency, high intrinsic clearance and high human plasma protein binding. Compounds achieving in vitro study criteria were selected for in vivo evaluation. Pharmacokinetic half-lives, inhibition of bronchoconstriction and duration of action, as well as systemic side effects, induced by the compounds were assessed in guinea-pig models. Compounds with a long duration of action and good therapeutic index were identified and AZD8683 was selected for progression to the clinic.


Subject(s)
Cycloheptanes/chemistry , Cycloheptanes/pharmacology , Muscarinic Antagonists/administration & dosage , Muscarinic Antagonists/chemistry , Pulmonary Disease, Chronic Obstructive/drug therapy , Administration, Inhalation , Animals , Bronchoconstriction/drug effects , Cycloheptanes/pharmacokinetics , Disease Models, Animal , Guinea Pigs , Humans , Molecular Structure , Muscarinic Antagonists/pharmacokinetics , Receptors, Muscarinic/chemistry , Receptors, Muscarinic/metabolism
12.
Transpl Int ; 26(1): 22-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23137339

ABSTRACT

We have recently described the immunosuppressive properties of AR-C117977 and AR-C122982, representatives of a group of compounds identified as inhibitors of lactate transporters (monocarboxylate transporters; MCTs). These compounds demonstrate the potential therapeutic usefulness of inhibiting MCT-1, but their physical and metabolic properties made them unsuitable for further development. We have therefore tried to find analogues with similar immunosuppressive efficacy and a more suitable profile for oral administration. Five analogues of AR-C117977 were synthesised and screened for binding to the transporter, for inhibition of proliferation of both human and rat lymphocytes, for in vivo activity in a model of graft-versus-host (GvH) response in the rat, and in high- and low-responder cardiac transplant models in the rat. There was a good correlation between levels of binding of the five analogues to MCT and their inhibition of lymphocyte proliferation in human and rat cells. Furthermore, activity in both the GvH response and the cardiac transplant models correlated well with the determined concentrations of test compound in plasma. These findings on new analogues of MCT-1 inhibitors have taken us further towards defining the pharmacokinetic properties that may help to identify future drug candidates among inhibitors of MCT-1.


Subject(s)
Immunosuppressive Agents/pharmacology , Monocarboxylic Acid Transporters/antagonists & inhibitors , Symporters/antagonists & inhibitors , Animals , Graft Survival , Graft vs Host Disease/etiology , Heart Transplantation , Heterocyclic Compounds/pharmacokinetics , Heterocyclic Compounds/pharmacology , Heterocyclic Compounds/toxicity , Humans , Male , Rats , Rats, Inbred Lew
13.
Bioorg Med Chem Lett ; 22(24): 7702-6, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23142617

ABSTRACT

The discovery of potent small molecule dual antagonists of the human CCR3 and H(1) receptors is described for the treatment of allergic diseases, for example, asthma and allergic rhinitis. Optimizing in vitro potency and metabolic stability, starting from a CCR1 lead compound, led to compound 20 with potent dual CCR3/H(1) activity and in vitro metabolic stability.


Subject(s)
Drug Discovery , Hydroxamic Acids/pharmacology , Piperidines/pharmacology , Receptors, CCR3/antagonists & inhibitors , Receptors, Histamine H1/metabolism , Animals , Hepatocytes/chemistry , Hepatocytes/metabolism , Humans , Hydroxamic Acids/chemistry , Hydroxamic Acids/metabolism , Microsomes, Liver/chemistry , Microsomes, Liver/metabolism , Piperidines/chemistry , Piperidines/metabolism , Rats , Structure-Activity Relationship , Tissue Distribution
14.
Bioorg Med Chem Lett ; 22(24): 7707-10, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23116889

ABSTRACT

The second part of this communication focuses on the resolution of issues surrounding the series of hydroxyamide phenoxypiperidine CCR3/H(1) dual antagonists described in Part I. This involved further structural exploration directed at reducing metabolism and leading to the identification of compound 60 with a greatly improved in vivo pharmacokinetic profile.


Subject(s)
Drug Discovery , Piperidines/pharmacology , Receptors, CCR3/antagonists & inhibitors , Receptors, Histamine H1/metabolism , Animals , Dogs , Hepatocytes/chemistry , Hepatocytes/metabolism , Humans , Microsomes, Liver/chemistry , Microsomes, Liver/metabolism , Piperidines/chemistry , Piperidines/metabolism , Rats , Structure-Activity Relationship , Tissue Distribution
15.
J Craniofac Surg ; 23(5): e405-7, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22976686

ABSTRACT

Free fibula transfer has become the workhorse in mandibular reconstruction. Total mandibular reconstruction is an uncommon procedure with added complexity. Numerous techniques have been described for such reconstruction, many requiring a temporomandibular joint prosthesis. We present a novel method where simultaneous bilateral free fibula transfer utilizing preoperative virtual surgical planning was used to produce a total autogenous reconstruction. The virtual surgical planning allows to effectively quantify the bone stock required preoperatively and facilitates intraoperative modeling of the fibula. Therefore, a more anatomically correct reconstruction is obtained resulting in improved functional and aesthetic outcomes.


Subject(s)
Fibula/transplantation , Mandibular Reconstruction/methods , Anti-Bacterial Agents/therapeutic use , Bone Plates , Device Removal , Female , Humans , Hyperbaric Oxygenation , Middle Aged , Range of Motion, Articular , Surgical Wound Infection/therapy
16.
J Pediatr Pharmacol Ther ; 17(4): 340-50, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23413048

ABSTRACT

Oral mucositis affects more than three-fourths of patients undergoing chemotherapy and represents a significant burden to patients and caregivers. Lesions develop as a result of chemotherapeutic agents attacking the rapidly dividing cells of the gastrointestinal tract. Severity can range from mild, painless tissue changes to bleeding ulcerations that prevent oral intake and require narcotic pain relievers. Oral mucositis also leads to an increased risk of infection and can often delay further chemotherapy treatment. A number of assessment scales have been developed to better qualify the symptoms associated with this condition. Few pharmacologic agents have been approved to either prevent the development or alleviate the symptoms of oral mucositis. Current options include the use of antimicrobial mouthwashes, amino acid rinses, and topical healing agents. Palifermin, a keratinocyte growth factor, may be a future option after its use in children is explored. With achievements in other areas of supportive care in patients undergoing chemotherapy, oral mucositis should represent the forefront of new research. This review will provide a comprehensive examination of available options for children who have oral mucositis.

17.
Environ Sci Pollut Res Int ; 19(3): 821-34, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21948131

ABSTRACT

INTRODUCTION: Public and scientific concern has grown over the last decade in Canada over the cosmetic use of pesticides in urban centers. With this in mind, a national survey was designed to monitor eight commonly used herbicides in urban rivers and streams across Canada. MATERIALS AND METHODS: To coordinate sample collections across the country, samples were collected monthly on one of two predetermined dates from April to September, 2007 from 19 sites within 16 watersheds, including 15 sites downstream of urban lands and two reference sites. Water samples were also collected approximately three times from each watershed during or after precipitation events. All samples were collected using a common sampling protocol and all were analyzed using the same analytical laboratories. RESULTS AND DISCUSSION: The herbicides 2,4-D, mecoprop, dicamba, glyphosate and its major metabolite aminomethylphosphonic acid (AMPA) were most frequently detected. Using either herbicide concentrations upstream/downstream of urban centers or bromoxynil and clopyralid as indictors of agricultural inputs of herbicides to streams, it was clear that environmental concentrations of these herbicides downstream of urban areas were linked to urban use in Canada. Herbicide concentrations in streams draining urban areas were greater during or after significant rainfall events and, with the exception of glyphosate, were significantly greater in the Province of Ontario. Herbicide concentrations were not correlated to the proportion of the watersheds in urban land use. Also, there was no difference in seasonal patterns of herbicide concentrations across urban centers when grouped in five geographic areas. None of the herbicide concentrations measured exceeded existing Canadian Water Quality Guidelines for the protection of aquatic life. CONCLUSIONS: This is the first time a national survey of pesticides in urban rivers has been carried out in a consistent fashion across Canada. Concentrations of 2,4-D, mecoprop, dicamba, glyphosate, and AMPA were linked to urban use and frequently detected in all geographic areas. However, geographic differences in concentration suggested differences in usage or stream connectivity patterns among urban centers. Some jurisdictions in Canada have recently restricted cosmetic use of pesticides and it would be interesting to determine whether such restrictions will lead to reduced pesticide concentrations in urban streams.


Subject(s)
Glycine/analogs & derivatives , Herbicides/analysis , Rivers/chemistry , Water Pollutants, Chemical/analysis , 2,4-Dichlorophenoxyacetic Acid/analysis , 2-Methyl-4-chlorophenoxyacetic Acid/analogs & derivatives , 2-Methyl-4-chlorophenoxyacetic Acid/analysis , Canada , Chemical Phenomena , Dicamba/analysis , Glycine/analysis , Herbicides/chemistry , Hydrogen-Ion Concentration , Isoxazoles , Organophosphonates/analysis , Pilot Projects , Seasons , Tetrazoles , Urbanization , Water Pollutants, Chemical/chemistry , Water Quality , Glyphosate
20.
Environ Toxicol Chem ; 29(2): 373-379, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20821456

ABSTRACT

Concentrations of 24 trace metals were assessed in gravid ovaries and in muscle of female juvenile and adult female goldeye (Hiodon alosoides), a fish with both low annual growth (16 g/year as adults) and a long life span (maximum longevity of 30 years). It was hypothesized that adult fish with these life-history characteristics would maintain stable concentrations of metals in their tissues with higher levels of essential elements compared with those that are potentially toxic. As hypothesized, the concentration of most metals in muscle of adult female goldeye was similar at all ages, suggesting that uptake and excretion of metals was equal. Mercury was a notable exception. Total Hg concentrations in muscle of adults increased throughout life from a mean of 206 ng/g wet weight at age 8 to 809 ng/g at age 28, or by 26.2 ng/g/year. Concentrations of Hg were low in ovaries (mean 21.1 ng/g wet wt) compared to the mean for muscle, only 7% of the concentration in muscle. This was the lowest percent of muscle concentration of all 24 metals. Concentrations of Al, Ba, La, V, and Mn were significantly greater in muscle of juveniles and in ovaries than in muscle of adults. Concentrations of 13 metals were higher in ovaries relative to muscle, seven were similar, and four were depleted. Silver was enriched by over 50-fold in ovaries. Overall, the present study suggests that low concentrations of some metals in muscle of adult female goldeye, relative to concentrations in female juveniles and ovaries, may be maintained in part by transfer of metals to the external environment in eggs at spawning.


Subject(s)
Fishes/metabolism , Mercury/metabolism , Metals/metabolism , Water Pollutants, Chemical/metabolism , Animals , Female , Muscles/metabolism , Ovary/metabolism
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