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1.
Arch Environ Contam Toxicol ; 67(2): 234-44, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24799048

ABSTRACT

The widespread use of herbicides across the globe has increased the probability of synthetic chemicals entering freshwater habitats. On entering aquatic habitats, these chemicals target and disrupt both physiological and behavioral functioning in various aquatic organisms. Herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D), can have negative impacts on chemoreception because these receptor cells are in direct contact with water-soluble chemicals in the environment. Studies focusing on lethal concentration (LC50) levels may understate the impact of herbicides within aquatic habitats because damage to the chemoreceptors can result in modified behaviors or lack of appropriate responses to environmental or social cues. The purpose of this experiment was to determine whether exposure to sublethal levels of 2,4-D alters the foraging behaviors of crayfish Orconectes rusticus. We hypothesized that crayfish exposed to greater concentrations of 2,4-D would be less successful in locating food or on locating food would consume smaller amounts possibly due to an inability to recognize the food odors in the contaminated waters. Crayfish were exposed to three sublethal levels of 2,4-D for 96 h and placed into a Y-maze system with a fish gelatin food source placed randomly in the right or left arm. Average walking speed, average time spent in the correct arm, and percent consumption were analyzed. Our data show that crayfish were impaired in their ability to forage effectively. These inabilities to locate and consume adequate amounts of food could result in lower body weights and decreased fitness in populations of crayfish exposed to 2,4-D in natural habitats.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/toxicity , Astacoidea/physiology , Feeding Behavior/drug effects , Herbicides/toxicity , Water Pollutants, Chemical/toxicity , Animals , Astacoidea/drug effects , Ecosystem
2.
Methods Mol Biol ; 2626: 399-444, 2023.
Article in English | MEDLINE | ID: mdl-36715918

ABSTRACT

Citizen science is a productive approach to include non-scientists in research efforts that impact particular issues or communities. In most cases, scientists at advanced career stages design high-quality, exciting projects that enable citizen contribution, a crowdsourcing process that drives discovery forward and engages communities. The challenges of having citizens design their own research with no or limited training and providing access to laboratory tools, reagents, and supplies have limited citizen science efforts. This leaves the incredible life experiences and immersion of citizens in communities that experience health disparities out of the research equation, thus hampering efforts to address community health needs with a full picture of the challenges that must be addressed. Here, we present a robust and reproducible approach that engages participants from Grade 5 through adult in research focused on defining how diet impacts disease signaling. We leverage the powerful genetics, cell biology, and biochemistry of Drosophila oogenesis to define how nutrients impact phenotypes associated with genetic mutants that are implicated in cancer and diabetes. Participants lead the project design and execution, flipping the top-down hierarchy of the prevailing scientific culture to co-create research projects and infuse the research with cultural and community relevance.


Subject(s)
Drosophila , Public Health , Animals , Research
3.
J Interpers Violence ; 36(19-20): 9393-9415, 2021 10.
Article in English | MEDLINE | ID: mdl-31387477

ABSTRACT

Increasingly, researchers and practitioners are examining connections between public and private cycles of violence. In complex emergency settings, these cycles of violence often intersect with conflicting norms and values as societies work toward sustainable peace. Gender norms, particularly norms of masculinity, are not often highlighted in transdisciplinary violence studies. Furthermore, few studies on either subject capture the perspectives and experiences of adolescent boys. This study seeks to explore adolescent boys' (13-17 years) experiences with violence at home and in the community in "post-conflict" Colombia. Thematic qualitative analysis of 20 interview transcripts from 14 Colombian boys in Cundinamarca (n = 5) and Córdoba (n = 9) revealed themes of conflict avoidance, hegemonic masculinity, and opportunities for change in the form of positive coping habits. Further research into social and emotional coping behaviors and linkages to perpetuating violence between adolescence and adulthood is needed.


Subject(s)
Masculinity , Violence , Adolescent , Adult , Colombia , Humans , Male , Surveys and Questionnaires
4.
Animals (Basel) ; 11(7)2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34208877

ABSTRACT

The first few months of life are of great importance to the longevity and lifetime performance of dairy cows. The nutrition, environment and healthcare management of heifer calves must be sufficient to minimise exposure to stress and disease and enable them to perform to their genetic potential. Lack of reporting of farm management practices in Northern Ireland (NI) makes it difficult to understand where issues impacting health, welfare and performance may occur in the rearing process. The objective of this study was to investigate housing design and management practices of calves on 66 dairy farms across NI over a 3-month period and also identify areas that may cause high risk of poor health and performance in dairy calves. An initial survey was used to detail housing and management practices, with two subsequent visits to each farm used to collect animal and housing-based measurements linked to hygiene management, animal health and performance. Large variations in key elements such as weaning criteria and method, calf grouping method used, nutritional feed plane, and routine hygiene management were identified. The specification of housing, in particular ventilation and stocking density, was highlighted as a potential limiting factor for calf health and performance. Lack of measurement of nutritional inputs, hygiene management practices and calf performance was observed. This poses a risk to farmers' ability to ensure the effectiveness of key management strategies and recognise poor calf performance and health.

5.
Dev Comp Immunol ; 104: 103559, 2020 03.
Article in English | MEDLINE | ID: mdl-31751628

ABSTRACT

Herein, we characterize transcription factor NF-κB from the demosponge Amphimedon queenslandica (Aq). Aq-NF-κB is most similar to NF-κB p100/p105 among vertebrate proteins, with an N-terminal DNA-binding domain, a C-terminal Ankyrin (ANK) repeat domain, and a DNA binding-site profile akin to human NF-κB proteins. Like mammalian NF-κB p100, C-terminal truncation allows nuclear translocation of Aq-NF-κB and increases its transcriptional activation activity. Expression of IκB kinases (IKKs) induces proteasome-dependent C-terminal processing of Aq-NF-κB in human cells, and processing requires C-terminal serines in Aq-NF-κB. Unlike NF-κB p100, C-terminal sequences of Aq-NF-κB do not inhibit its DNA-binding activity. Tissue of a black encrusting demosponge contains NF-κB site DNA-binding activity, as well as nuclear and processed NF-κB. Treatment of sponge tissue with LPS increases both DNA-binding activity and processing of NF-κB. A. queenslandica transcriptomes contain homologs to upstream NF-κB pathway components. This is first functional characterization of NF-κB in sponge, the most basal multicellular animal.


Subject(s)
Conserved Sequence/genetics , DNA-Binding Proteins/genetics , NF-kappa B/genetics , Porifera/immunology , Protein Domains/genetics , Animals , DNA-Binding Proteins/metabolism , Evolution, Molecular , Gene Expression Regulation , NF-kappa B/metabolism , Signal Transduction , Transcription, Genetic
6.
Cancer Biol Ther ; 18(7): 519-533, 2017 Jul 03.
Article in English | MEDLINE | ID: mdl-28494185

ABSTRACT

The cancer-predisposing Lynch Syndrome (LS) arises from germline mutations in DNA mismatch repair (MMR) genes, predominantly MLH1, MSH2, MSH6, and PMS2. A major challenge for clinical diagnosis of LS is the frequent identification of variants of uncertain significance (VUS) in these genes, as it is often difficult to determine variant pathogenicity, particularly for missense variants. Generic programs such as SIFT and PolyPhen-2, and MMR gene-specific programs such as PON-MMR and MAPP-MMR, are often used to predict deleterious or neutral effects of VUS in MMR genes. We evaluated the performance of multiple predictive programs in the context of functional biologic data for 15 VUS in MLH1, MSH2, and PMS2. Using cell line models, we characterized VUS predicted to range from neutral to pathogenic on mRNA and protein expression, basal cellular viability, viability following treatment with a panel of DNA-damaging agents, and functionality in DNA damage response (DDR) signaling, benchmarking to wild-type MMR proteins. Our results suggest that the MMR gene-specific classifiers do not always align with the experimental phenotypes related to DDR. Our study highlights the importance of complementary experimental and computational assessment to develop future predictors for the assessment of VUS.


Subject(s)
Biomarkers, Tumor , DNA Mismatch Repair , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/genetics , Genetic Variation , Alleles , Amino Acid Substitution , Cell Survival/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , DNA Damage , DNA-Binding Proteins/metabolism , Female , Gene Expression , Humans , Models, Molecular , Molecular Conformation , Protein Binding , RNA, Messenger/genetics , RNA, Messenger/metabolism , Structure-Activity Relationship
7.
Article in English | MEDLINE | ID: mdl-12692751

ABSTRACT

OBJECTIVES: We previously showed that an angiotensin-converting enzyme inhibitor (captopril) or an angiotensin receptor blocker (losartan) reduced infarct size and improved endothelial function in a rat model of ischaemia-reperfusion. The present study was undertaken to see if aspirin (ASA) antagonised the beneficial effects of captopril or losartan. METHODS: One hundred and fourteen Sprague-Dawley rats were randomised into six groups; Control, ASA, captopril, losartan, ASA+captopril, and ASA+losartan. ASA, captopril or losartan were given at a concentration of 40 mg/kg/day in drinking water. After six weeks of pre-treatment, the rats were subjected to 17 minutes of left anterior descending coronary artery occlusion and 120 minutes of reperfusion, with haemodynamic and ECG monitoring. During the reperfusion period, the effective refractory period (ERP), ventricular fibrillation threshold (VFT) and bleeding time (BT) were measured. In fresh aortic rings precontracted with phenylephrine, endothelium-dependent and -independent relaxations were assessed using acetylcholine and nitroglycerin. RESULTS: Haemodynamic changes were not different between the groups. Serum ASA concentrations were 0.5, 1.1 and 0.6 mg/dl in the ASA, ASA+captopril and ASA+losartan groups, respectively, and BT was prolonged (p<0.01). ASA alone reduced endothelium-dependent relaxation (-29+8 vs. -69+11%, p<0.01), but did not change endothelium-independent relaxation. ASA did not affect endothelial relaxation induced by acetylcholine in the presence of either captopril or losartan. Angiotensin I and ERP were elevated by captopril and losartan. Angiotensin II and VFT were elevated by losartan. ASA with captopril, captopril and losartan equally reduced infarct size, compared with control (39+3, 39+4, and 39+5 vs. 53+3%, all p<0.05). CONCLUSIONS: Captopril and losartan had similar cardiovascular protective effects in a rat model of ischaemia-reperfusion. Aspirin did not attenuate the cardiovascular protective effects of captopril or losartan.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aspirin/pharmacology , Captopril/pharmacology , Myocardial Infarction/drug therapy , Angiotensin I/blood , Angiotensin II/blood , Angiotensin Receptor Antagonists , Animals , Anti-Arrhythmia Agents/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/blood , Aspirin/blood , Bleeding Time , Disease Models, Animal , Endothelium, Vascular/drug effects , Female , Hemodynamics , Losartan/pharmacology , Myocardial Infarction/pathology , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/pathology , Rats , Rats, Sprague-Dawley , Refractory Period, Electrophysiological/drug effects , Vasodilation/drug effects , Ventricular Fibrillation/drug therapy , Ventricular Fibrillation/pathology
8.
Article in English | MEDLINE | ID: mdl-11984749

ABSTRACT

INTRODUCTION: Both second hand smoke (SHS) and the renin-angiotensin system (RAS) contribute to endothelial dysfunction and increased infarct size in a rat ischaemia-reperfusion model. However, the potential interaction between SHS and the RAS is unknown. METHODS: Eighty-four rats were randomised into four groups: group C was a normal control; L was given 40 mg/kg/day of losartan in drinking water; SC and SL were exposed to SHS (smoking chamber) and given regular water or 40 mg/kg/day of losartan in drinking water, respectively. After six weeks of pre-treatment, rats were subjected to 17 minutes of left coronary artery occlusion and 2 hours of reperfusion with haemodynamic and ECG monitoring. RESULTS: Haemodynamics were not significantly different among the four groups. Losartan increased the threshold for ventricular fibrillation (p=0.0001) and reduced spontaneous ventricular arrhythmias (p=0.002) during ischaemia-reperfusion, while SHS did not (p=0.713, 0.110), and there was no interaction between losartan and SHS. The maximal endothelium-dependent vasorelaxation induced by a calcium ionophore (A23187) was increased by losartan (p=0.007). Myocardial infarct size was smaller in the losartan groups (p=0.032), larger in the SHS groups (p=0.0001), and there was no significant interaction. CONCLUSION: In conclusion, losartan decreased infarct size and increased endothelium-dependent vasorelaxation. SHS exposure impaired endothelial function and increased infarct size. The effects of losartan and SHS were consistently independent of each other. These results suggest that the RAS does not contribute to the adverse effects of SHS.


Subject(s)
Endothelium, Vascular/physiopathology , Myocardial Infarction/physiopathology , Renin-Angiotensin System/physiology , Tobacco Smoke Pollution/adverse effects , Angiotensin II/blood , Animals , Antihypertensive Agents/pharmacology , Arrhythmias, Cardiac/physiopathology , Electrocardiography/drug effects , Endothelial Growth Factors/metabolism , Endothelium, Vascular/pathology , Female , Hemodynamics/physiology , Losartan/pharmacology , Lymphokines/metabolism , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/physiology , Myocardial Infarction/pathology , Nicotine/blood , Rats , Rats, Sprague-Dawley , Refractory Period, Electrophysiological/drug effects , Renin/blood , Renin-Angiotensin System/drug effects , Reperfusion Injury/physiopathology , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors , Ventricular Fibrillation/physiopathology
9.
J Cardiovasc Pharmacol ; 46(3): 325-32, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16116338

ABSTRACT

Although an inverse relationship between dehydroepiandrosterone sulfate (DHEAS) and coronary artery disease has been demonstrated in men, the vascular effects of DHEAS are not well defined. The vasoactive effects of intracoronary DHEAS and testosterone (0.1 nM to 1 microM) were examined in vivo in 24 pigs. Epicardial cross-sectional area was measured by intravascular ultrasound, and coronary flow velocity by intravascular Doppler velocimetry. We also examined the effects of antagonism of the androgen receptor, nitric oxide synthase, and potassium channels on DHEAS-induced vasodilation in vitro in coronary rings from male and female pig hearts. DHEAS and testosterone induced increases in cross-sectional area, average peak velocity, and coronary blood flow. The maximal increase in coronary blood flow in response to testosterone was 1.26-fold (P=0.02), and in average peak velocity 1.43-fold (P=0.05), greater than that to DHEAS, whereas increases in cross-sectional area were similar. Vasodilation to both hormones was rapid, with maximal responses occurring <10 minutes after administration. In vitro, DHEAS and testosterone induced vasodilation in coronary rings, greater with testosterone. At doses of 0.1 and 1 microM, the vasodilator effects of DHEAS and testosterone were inhibited by the androgen receptor antagonist flutamide but not the estrogen receptor antagonist ICI 182,780. At 10 microM, neither DHEAS- nor testosterone-induced vasorelaxation was inhibited by flutamide, ICI 182,780, L-NAME, or deendothelialization, but both were attenuated by pretreatment with glibenclamide. No gender differences were observed in any of the responses examined. In conclusion, DHEAS is an acute coronary artery vasodilator, but less potent than testosterone. Its effect might be mediated via androgen receptors and may involve ATP-sensitive potassium channels.


Subject(s)
Coronary Vessels/drug effects , Dehydroepiandrosterone Sulfate/pharmacology , Vasodilation/drug effects , ATP-Binding Cassette Transporters/drug effects , Androgen Antagonists/pharmacology , Animals , Coronary Circulation/drug effects , Coronary Vessels/diagnostic imaging , Echocardiography, Doppler , Endothelium, Vascular/physiology , Enzyme Inhibitors/pharmacology , Estradiol/analogs & derivatives , Estradiol/pharmacology , Female , Flutamide/pharmacology , Fulvestrant , Glyburide/pharmacology , Hemodynamics/drug effects , In Vitro Techniques , KATP Channels , Male , NG-Nitroarginine Methyl Ester/pharmacology , Pericardium/drug effects , Potassium Channel Blockers/pharmacology , Potassium Channels, Inwardly Rectifying/drug effects , Sex Characteristics , Swine , Testosterone/pharmacology
10.
J Am Coll Nutr ; 23(3): 197-204, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15190043

ABSTRACT

BACKGROUND: Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids. OBJECTIVE: To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects. DESIGN: The study was a randomized, double-blind, placebo-controlled design conducted over a 2 week period in 21 healthy adult subjects. Subjects were randomly assigned to daily intake of high-flavonoid (213 mg procyanidins, 46 mg epicatechin) or low-flavonoid dark chocolate bars (46 g, 1.6 oz). RESULTS: High-flavonoid chocolate consumption improved endothelium-dependent flow-mediated dilation (FMD) of the brachial artery (mean change = 1.3 +/- 0.7%) as compared to low-flavonoid chocolate consumption (mean change = -0.96 +/- 0.5%) (p = 0.024). No significant differences were noted in the resistance to LDL oxidation, total antioxidant capacity, 8-isoprostanes, blood pressure, lipid parameters, body weight or body mass index (BMI) between the two groups. Plasma epicatechin concentrations were markedly increased at 2 weeks in the high-flavonoid group (204.4 +/- 18.5 nmol/L, p < or = 0.001) but not in the low-flavonoid group (17.5 +/- 9 nmol/L, p = 0.99). CONCLUSION: Flavonoid-rich dark chocolate improves endothelial function and is associated with an increase in plasma epicatechin concentrations in healthy adults. No changes in oxidative stress measures, lipid profiles, blood pressure, body weight or BMI were seen.


Subject(s)
Biflavonoids , Cacao , Candy , Catechin/blood , Endothelium/physiology , Flavonoids/pharmacology , Proanthocyanidins , Adult , Analysis of Variance , Antioxidants/administration & dosage , Blood Pressure/drug effects , Body Mass Index , Body Weight/drug effects , Brachial Artery/drug effects , Brachial Artery/physiology , Catechin/administration & dosage , Double-Blind Method , Endothelium/drug effects , Female , Humans , Lipids/blood , Male , Middle Aged , Nitric Oxide/metabolism , Oxidative Stress/drug effects , Reference Values
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