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1.
Int J Neonatal Screen ; 7(4)2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34842611

ABSTRACT

Newborn screening (NBS) for Cystic Fibrosis (CF) is associated with improved outcomes. All US states screen for CF; however, CF NBS algorithms have high false positive (FP) rates. In New York State (NYS), the positive predictive value of CF NBS improved from 3.7% to 25.2% following the implementation of a three-tier IRT-DNA-SEQ approach using commercially available tests. Here we describe a modification of the NYS CF NBS algorithm via transition to a new custom next-generation sequencing (NGS) platform for more comprehensive cystic fibrosis transmembrane conductance regulator (CFTR) gene analysis. After full gene sequencing, a tiered strategy is used to first analyze only a specific panel of 338 clinically relevant CFTR variants (second-tier), followed by unblinding of all sequence variants and bioinformatic assessment of deletions/duplications in a subset of samples requiring third-tier analysis. We demonstrate the analytical and clinical validity of the assay and the feasibility of use in the NBS setting. The custom assay has streamlined our molecular workflow, increased throughput, and allows for bioinformatic customization of second-tier variant panel content. NBS aims to identify those infants with the highest disease risk. Technological molecular improvements can be applied to NBS algorithms to reduce the burden of FP referrals without loss of sensitivity.

2.
J Biol Chem ; 297(3): 101099, 2021 09.
Article in English | MEDLINE | ID: mdl-34418434

ABSTRACT

Cannabinoid receptor interacting protein 1a (CRIP1a) modulates CB1 cannabinoid receptor G-protein coupling in part by altering the selectivity for Gαi subtype activation, but the molecular basis for this function of CRIP1a is not known. We report herein the first structure of CRIP1a at a resolution of 1.55 Å. CRIP1a exhibits a 10-stranded and antiparallel ß-barrel with an interior comprised of conserved hydrophobic residues and loops at the bottom and a short helical cap at the top to exclude solvent. The ß-barrel has a gap between strands ß8 and ß10, which deviates from ß-sandwich fatty acid-binding proteins that carry endocannabinoid compounds and the Rho-guanine nucleotide dissociation inhibitor predicted by computational threading algorithms. The structural homology search program DALI identified CRIP1a as homologous to a family of lipidated-protein carriers that includes phosphodiesterase 6 delta subunit and Unc119. Comparison with these proteins suggests that CRIP1a may carry two possible types of cargo: either (i) like phosphodiesterase 6 delta subunit, cargo with a farnesyl moiety that enters from the top of the ß-barrel to occupy the hydrophobic interior or (ii) like Unc119, cargo with a palmitoyl or a myristoyl moiety that enters from the side where the missing ß-strand creates an opening to the hydrophobic pocket. Fluorescence polarization analysis demonstrated CRIP1a binding of an N-terminally myristoylated 9-mer peptide mimicking the Gαi N terminus. However, CRIP1a could not bind the nonmyristolyated Gαi peptide or cargo of homologs. Thus, binding of CRIP1a to Gαi proteins represents a novel mechanism to regulate cell signaling initiated by the CB1 receptor.


Subject(s)
Carrier Proteins/metabolism , Carrier Proteins/ultrastructure , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Amino Acid Sequence , Animals , Cannabinoids/metabolism , Carrier Proteins/genetics , Endocannabinoids , GTP-Binding Protein alpha Subunits, Gi-Go/genetics , GTP-Binding Protein alpha Subunits, Gi-Go/ultrastructure , Membrane Proteins/metabolism , Mice , Peptides/metabolism , Protein Binding , Protein Conformation , Receptor, Cannabinoid, CB1/metabolism , Receptor, Cannabinoid, CB1/ultrastructure , Receptors, Cannabinoid/metabolism , Receptors, Cannabinoid/ultrastructure
3.
Front Microbiol ; 12: 642600, 2021.
Article in English | MEDLINE | ID: mdl-34220736

ABSTRACT

Many species of the ciliate genus Strombidium can acquire functional chloroplasts from a wide range of algal prey and are thus classified as generalist non-constitutive mixotrophs. Little, however, is known about the influence of irradiance and prey availability on their ability to exploit the photosynthetic potential of the chloroplasts, and how this may explain their spatial and temporal distribution in nature. In this study, inorganic carbon uptake, growth, and ingestion rates were measured for S. cf. basimorphum under three different irradiances (10, 40, and 120 µmol photons m-2 s-1) when acclimated to three different prey densities (5 × 103, 1 × 104, and 4 × 104 cells mL-1), as well as when allowed to deplete the prey. After prey depletion, cultures survived without prey longest (∼6 days) at the medium irradiance treatment (40 µmol photons m-2 s-1), while ciliate density, inorganic carbon uptake rates, and cellular chl-a content declined fastest at the highest irradiance treatment. This indicates that the ciliates may be unable to maintain the chloroplasts functionally without replacement at high irradiances. Ingestion rates were not shown to be significantly influenced by irradiance. The maximum gross growth efficiency (GGE) in this study (1.1) was measured in cultures exposed to the medium test irradiance and lowest prey density treatment (5 × 103 cells mL-1). The relative contribution of inorganic carbon uptake to the ciliate carbon budget was also highest in this treatment (42%). A secondary GGE peak (0.99) occurred when cultures were exposed to the highest test irradiance and the medium prey density. These and other results suggest that S. cf. basimorphum, and other generalist non-constitutive mixotrophs, can flexibly exploit many different environmental conditions across the globe.

4.
Biomolecules ; 10(12)2020 11 27.
Article in English | MEDLINE | ID: mdl-33261012

ABSTRACT

Endocannabinoid signaling depends upon the CB1 and CB2 cannabinoid receptors, their endogenous ligands anandamide and 2-arachidonoylglycerol, and intracellular proteins that mediate responses via the C-terminal and other intracellular receptor domains. The CB1 receptor regulates and is regulated by associated G proteins predominantly of the Gi/o subtypes, ß-arrestins 1 and 2, and the cannabinoid receptor-interacting protein 1a (CRIP1a). Evidence for a physiological role for CRIP1a is emerging as data regarding the cellular localization and function of CRIP1a are generated. Here we summarize the neuronal distribution and role of CRIP1a in endocannabinoid signaling, as well as discuss investigations linking CRIP1a to development, vision and hearing sensory systems, hippocampus and seizure regulation, and psychiatric disorders including schizophrenia. We also examine the genetic and epigenetic association of CRIP1a within a variety of cancer subtypes. This review provides evidence upon which to base future investigations on the function of CRIP1a in health and disease.


Subject(s)
Neoplasms/metabolism , Receptors, Cannabinoid/metabolism , Schizophrenia/metabolism , Seizures/metabolism , Animals , Humans
5.
Orthopedics ; 43(5): e476-e479, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32745220

ABSTRACT

The authors report the case of an atraumatic femoral component fracture 10 years after primary total knee arthroplasty (TKA) with a modern cemented fixed bearing system. The patient, a 70-year-old man, had the complication without inciting trauma, and he subsequently had severe pain and disability. This rare mode of TKA failure occurred at the superolateral aspect of the femoral component's anterior flange. At the time of revision, no femoral osteolysis was seen and the backside of the prosthesis fracture fragment was found to be free of cement. To the authors' knowledge, this is the first case of femoral component fracture in a Vanguard TKA (Biomet, Warsaw, Indiana), and the first case of fracture in a modern cobalt-chrome alloy femoral component associated with aseptic cement debonding. Femoral component stress fracture is a rare but serious complication of TKA. Reports of femoral component fracture in early designs were attributed to geometric design flaws, whereas modern TKA designs appear to fail when ingrowth failure, aseptic debonding, or osteolysis result in inadequate bony support of the prosthesis. Careful attention to bone cuts in porous-coated uncemented TKA systems and proper cementing technique in cemented TKA systems may preclude this rare complication. In the case of severe osteolysis, early revision may prevent catastrophic implant failure. [Orthopedics. 2020;43(5):e476-e479.].


Subject(s)
Arthroplasty, Replacement, Knee/adverse effects , Femoral Fractures/etiology , Fractures, Stress/etiology , Knee Prosthesis/adverse effects , Aged , Bone Cements , Femur/surgery , Humans , Male , Prosthesis Failure , Reoperation/methods
6.
J Pers Assess ; 102(6): 792-803, 2020.
Article in English | MEDLINE | ID: mdl-31355680

ABSTRACT

People's self-concepts are subject to change through various processes, one of which is self-expansion. Self-expansion is a motivation to increase one's self-concept through engaging in novel, exciting, and interesting activities or by taking on one's partner's qualities. Despite the plethora of research on self-expansion, there has not been much work on whether people vary in their desire to expand. This study validates a new measure, called the Self-Expansion Preference Scale, to examine people's differing motivation for self-expansion. The sample included 611 participants who responded to 24 items, 12 of which pertained to self-expansion, a desire to increase the self-concept, and 12 of which pertained to self-conservation, a desire to maintain the self-concept. After reverse coding the 12 conserver items, an exploratory and confirmatory factor analysis indicated that there was a single dominant factor of self-expansion. The single-factor scale positively correlated with a series of both convergent measures (e.g., openness to experience) and predictive measures (e.g., hedonic well-being). Ultimately, the Self-Expansion Preference Scale offers new insight into a well-established process in an easily administered format. Looking forward, it would be interesting to see the implications of the scale as applied to romantic relationships, where self-expansion was initially researched.


Subject(s)
Psychometrics/instrumentation , Psychometrics/standards , Self Concept , Adult , Female , Humans , Male , Reproducibility of Results , Young Adult
7.
Body Image ; 30: 212-220, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31377478

ABSTRACT

The present study evaluated whether individuals with varying levels of trait body image flexibility differ in the severity, variability, and correlates of state body dissatisfaction experienced in their daily lives. One hundred and forty-seven women completed a baseline measure of trait body image flexibility, followed by a 7-day ecological momentary assessment phase in which participants self-reported state body dissatisfaction, disordered eating behavior, drive for thinness, and appearance comparisons at 10 semi-random intervals daily. Higher trait body image flexibility predicted lower average scores, less frequent reporting of high state body dissatisfaction, and less variability in their state body dissatisfaction ratings. Individuals with higher trait body image flexibility were also less likely to engage in a range of behaviors and cognitions previously shown to produce body dissatisfaction, including upward appearance comparisons, drive for thinness, binge eating, and dieting. However, few of these state-based relationships involving body dissatisfaction and these related behaviors and cognitions were moderated by trait body image flexibility. Overall, this pattern of findings suggests that body image flexible individuals may have less negative body image because they are less inclined to engage in behaviors and cognitions in their daily lives that encourage negative body image.


Subject(s)
Body Image/psychology , Drive , Feeding Behavior/psychology , Personal Satisfaction , Personality , Thinness/psychology , Adolescent , Adult , Australia , Ecological Momentary Assessment , Emotions , Female , Humans , Self Report , Young Adult
8.
PLoS One ; 14(5): e0216621, 2019.
Article in English | MEDLINE | ID: mdl-31071138

ABSTRACT

Longitudinal studies of chronic wasting disease (CWD) in the native host have provided considerable understanding of how this prion disease continues to efficiently spread among cervid species. These studies entail great cost in animal, time and financial support. A variety of methods have emerged including transgenic mouse bioassay, western blot, enzyme-linked immunoassay (ELISA), immunohistochemistry (IHC), serial protein misfolding cyclic amplification (sPMCA) and real time quaking-induced conversion (RT-QuIC), that deepen our understanding of this and other protein misfolding disorders. To further characterize an inoculum source used for ongoing CWD studies and to determine how the readouts from each of these assays compare, we assayed a CWD-positive brain pool homogenate (CBP6) and a mouse dilutional bioassay of this homogenate using the above detection methods. We demonstrate that: (i) amplification assays enhanced detection of amyloid seeding activity in the CWD+ cervid brain pool to levels beyond mouse LD50, (ii) conventional detection methods (IHC and western blot) performed well in identifying the presence of PrPSc in terminal brain tissue yet lack sufficient detection sensitivity to identify all CWD-infected mice, and (iii) the incorporation of amplification assays enhanced detection of CWD-infected mice near the LD50. This cross-platform analysis provides a basis to calibrate the relative sensitivities of CWD detection assays.


Subject(s)
Amyloid/analysis , Biological Assay/methods , Brain/metabolism , Deer/metabolism , Nucleic Acid Amplification Techniques/methods , Prions/analysis , Wasting Disease, Chronic/diagnosis , Animals , Brain/pathology , Mice , Mice, Transgenic , Prion Proteins/genetics , Prions/genetics , Wasting Disease, Chronic/transmission
9.
Clin Chem ; 63(4): 842-851, 2017 04.
Article in English | MEDLINE | ID: mdl-28196920

ABSTRACT

BACKGROUND: Pompe disease (PD) is the first lysosomal storage disorder to be added to the Recommended Uniform Screening Panel for newborn screening. This condition has a broad phenotypic spectrum, ranging from an infantile form (IOPD), with severe morbidity and mortality in infancy, to a late-onset form (LOPD) with variable onset and progressive weakness and respiratory failure. Because the prognosis and treatment options are different for IOPD and LOPD, it is important to accurately determine an individual's phenotype. To date, no enzyme assay of acid α-glucosidase (GAA) has been described that can differentiate IOPD vs LOPD using blood samples. METHODS: We incubated 10 µL leukocyte lysate and 25 µL GAA substrate and internal standard (IS) assay cocktail for 1 h. The reaction was purified by a liquid-liquid extraction. The extracts were evaporated and reconstituted in 200 µL methanol and analyzed by LC-MS/MS for GAA activity. RESULTS: A 700-fold higher analytical range was observed with the LC-MS/MS assay compared to the fluorometric method. When GAA-null and GAA-containing fibroblast lysates were mixed, GAA activity could be measured accurately even in the range of 0%-1% of normal. The leukocyte GAA activity in IOPD (n = 4) and LOPD (n = 19) was 0.44-1.75 nmol · h-1 · mg-1 and 2.0-6.5 nmol · h-1 · mg-1, respectively, with no overlap. The GAA activity of pseudodeficiency patients ranged from 3.0-28.1 nmol · h-1 · mg-1, showing substantial but incomplete separation from the LOPD group. CONCLUSIONS: This assay allows determination of low residual GAA activity in leukocytes. IOPD, LOPD, and pseudodeficiency patients can be partially differentiated by measuring GAA using blood samples.


Subject(s)
Chromatography, Liquid , Glycogen Storage Disease Type II/blood , Leukocytes/enzymology , Neonatal Screening , Tandem Mass Spectrometry , alpha-Glucosidases/blood , Adult , Alleles , Child , Child, Preschool , Glycogen Storage Disease Type II/diagnosis , Glycogen Storage Disease Type II/enzymology , Humans , Infant , Infant, Newborn , Leukocytes/metabolism , alpha-Glucosidases/genetics , alpha-Glucosidases/metabolism
10.
Hum Mutat ; 37(2): 201-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26538069

ABSTRACT

Infants are screened for cystic fibrosis (CF) in New York State (NYS) using an IRT-DNA algorithm. The purpose of this study was to validate and assess clinical validity of the US FDA-cleared Illumina MiSeqDx CF 139-Variant Assay (139-VA) in the diverse NYS CF population. The study included 439 infants with CF identified via newborn screening (NBS) from 2002 to 2012. All had been screened using the Abbott Molecular CF Genotyping Assay or the Hologic InPlex CF Molecular Test. All with CF and zero or one mutation were tested using the 139-VA. DNA extracted from dried blood spots was reliably and accurately genotyped using the 139-VA. Sixty-three additional mutations were identified. Clinical sensitivity of three panels ranged from 76.2% (23 mutations recommended for screening by ACMG/ACOG) to 79.7% (current NYS 39-mutation InPlex panel), up to 86.0% for the 139-VA. For all, sensitivity was highest in Whites and lowest in the Black population. Although the sample size was small, there was a nearly 20% increase in sensitivity for the Black CF population using the 139-VA (68.2%) over the ACMG/ACOG and InPlex panels (both 50.0%). Overall, the 139-VA is more sensitive than other commercially available panels, and could be considered for NBS, clinical, or research laboratories conducting CF screening.


Subject(s)
Biological Assay , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis/diagnosis , Cystic Fibrosis/genetics , Mutation , Black People , Cystic Fibrosis/ethnology , Cystic Fibrosis/pathology , Dried Blood Spot Testing , Female , Genetic Testing , Genotyping Techniques , Hispanic or Latino , Humans , Infant , Infant, Newborn , Male , Neonatal Screening , Sensitivity and Specificity , White People
11.
J Pain Symptom Manage ; 43(4): 663-78, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22464352

ABSTRACT

CONTEXT: The Provincial Palliative Care Integration Project (PPCIP) was implemented in Ontario, Canada, to enhance the quality of palliative care delivery. The PPCIP promoted collaboration and integration across service sectors to improve screening and assessment, palliative care processes, as well as clinician practice and outcomes for cancer patients. OBJECTIVES: The project involved 1) implementation of the Edmonton Symptom Assessment System (ESAS) for symptom screening, 2) use of "rapid-cycle change" quality improvement processes to improve screening and symptom management, and 3) improvements in integration and access to palliative care services. METHODS: Symptom scores were collected and made accessible to the care team through a web-based tool and kiosk technology, which helped patients enter their ESAS scores at each visit to the regional cancer center or at home with their nurse. Symptom response data were gathered through clinical chart audits. RESULTS: Within one year of implementation, regional cancer centers saw improvements in symptom screening (54% of lung cancer patients), symptom control (69% of patients with pain scores and 31% of patients with dyspnea scores seven or more were reduced to six or less within 72 hours), and functional assessment (23% of all patients and 64% of palliative care clinic patients). ESAS screening rates reached 29%, and functional assessment reached 26% of targeted home care patients. CONCLUSION: The PPCIP demonstrated that significant strides in symptom screening and response can be achieved within a year using rapid-cycle change and collaborative approaches. It showed that both short- and long-term improvement require ongoing facilitation to embed the changes in system design and change the culture of clinical practice.


Subject(s)
Neoplasms/epidemiology , Neoplasms/therapy , Pain Management/standards , Pain/epidemiology , Palliative Care/statistics & numerical data , Palliative Care/standards , Quality Improvement/statistics & numerical data , Aged, 80 and over , Comorbidity , Female , Humans , Male , Middle Aged , Ontario/epidemiology , Pain Management/statistics & numerical data , Pain Measurement/standards , Pain Measurement/statistics & numerical data , Patient Satisfaction , Treatment Outcome
12.
Work ; 41 Suppl 1: 846-50, 2012.
Article in English | MEDLINE | ID: mdl-22316827

ABSTRACT

Studies have shown that increased computer use among adults in occupational settings is associated with the development of cumulative trauma disorders; however, the need to address how adult-sized mice and keyboards are affecting children is becoming increasingly important as both access to and use of computers is increasing among today's youth. To address the potential mismatch that exists between child stature and computer input device size and activation force, we have applied existing, age-specific, anthropometric data to elements of device design, including mouse size (length, width, height, switch location), and mouse-button activation forces. Trends supported the development of smaller computer input devices with lower activation forces for smaller statured individuals including children. Distinct and consistent trends in size delineations were seen across gender and age groups-trends that correlate well with grades and schooling in the United States education system . Three to four mouse sizes would be recommended: a mouse sized for adult and high school males; one for adult and high school females and junior high males; one for elementary school children, aged 6 to 10 years; and possibly a mouse for the smallest users who are less than six years old.


Subject(s)
Computer Peripherals/standards , Hand/anatomy & histology , Adolescent , Adult , Anthropometry , Child , Child, Preschool , Equipment Design , Female , Hand/physiology , Hand Strength , Humans , Male
13.
Psychooncology ; 21(4): 357-64, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21308858

ABSTRACT

OBJECTIVE: In late 2006, Cancer Care Ontario launched a quality improvement initiative to implement routine screening with the Edmonton Symptom Assessment System (ESAS) for cancer patients seen in fourteen Regional Cancer Centres throughout the province. METHODS: A central team: created a provincial project plan and management and evaluation framework; developed common tools and provided expert coaching and guidance, provincial data analysis, progress reporting and program evaluation. Regional Steering Committees and Improvement teams were accountable for planning and coordination within each region and supported by a funded Regional Improvement Coordinator. A hybrid model for quality improvement facilitated process improvements and uptake of screening. RESULTS: Challenges to implementation included: lack of consensus on the chosen screening tool, lack of guidance for assessment or management of high scores, concern of inadequate time or resources to address issues identified by the screening, data entry was labour intensive, resistance to change and challenges to the traditional care model. Essential components for success were: centralized project management, a person dedicated to implementation of the project locally, clinical champions, clearly identified aims, monthly regional data reporting and implementation of quality improvement methodologies with expectations for performance. To achieve screening aims many centres engaged all members of the team, examined the roles of the different members and reorganized workflow and responsibilities and changed booking times. In March 2010, approximately 25,000 ESAS's were completed in the regional cancer centres across Ontario, with 60% of lung cancer patients and almost 40% of all other cancer patients who visited the Regional Cancer Centres screened. CONCLUSION: Routine physical and psychological distress screening is possible within regional cancer centres. Although considerable effort and investment is required, it is worthwhile as it helps create a culture that is more patient-centered.


Subject(s)
Mass Screening/methods , Neoplasms/complications , Pain/complications , Stress, Psychological/complications , Stress, Psychological/diagnosis , Cancer Care Facilities/organization & administration , Humans , Neoplasms/physiopathology , Neoplasms/psychology , Ontario , Program Evaluation
14.
IEEE Trans Med Imaging ; 28(11): 1836-49, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19884068

ABSTRACT

Generating 3-D images of the heart during interventional procedures is a significant challenge. In addition to real time fluoroscopy, angiographic C-arm systems can also now be used to generate 3-D/4-D CT images on the same system. One protocol for cardiac CT uses ECG triggered multisweep scans. A 3-D volume of the heart at a particular cardiac phase is then reconstructed by applying Feldkamp (FDK) reconstruction to the projection images with retrospective ECG gating. In this work we introduce a unified framework for heart motion estimation and dynamic cone-beam reconstruction using motion corrections. The benefits of motion correction are 1) increased temporal and spatial resolution by removing cardiac motion which may still exist in the ECG gated data sets and 2) increased signal-to-noise ratio (SNR) by using more projection data than is used in standard ECG gated methods. Three signal-enhanced reconstruction methods are introduced that make use of all of the acquired projection data to generate a 3-D reconstruction of the desired cardiac phase. The first averages all motion corrected back-projections; the second and third perform a weighted averaging according to 1) intensity variations and 2) temporal distance relative to a time resolved and motion corrected reference FDK reconstruction. In a comparison study seven methods are compared: nongated FDK, ECG-gated FDK, ECG-gated, and motion corrected FDK, the three signal-enhanced approaches, and temporally aligned and averaged ECG-gated FDK reconstructions. The quality measures used for comparison are spatial resolution and SNR. Evaluation is performed using phantom data and animal models. We show that data driven and subject-specific motion estimation combined with motion correction can decrease motion-related blurring substantially. Furthermore, SNR can be increased by up to 70% while maintaining spatial resolution at the same level as is provided by the ECG-gated FDK. The presented framework provides excellent image quality for cardiac C-arm CT.


Subject(s)
Algorithms , Cone-Beam Computed Tomography/methods , Heart , Image Processing, Computer-Assisted/methods , Signal Processing, Computer-Assisted , Animals , Computer Simulation , Electrocardiography , Heart/diagnostic imaging , Heart/physiology , Motion , Phantoms, Imaging , Surgery, Computer-Assisted/methods , Swine
15.
Mar Environ Res ; 58(2-5): 675-9, 2004.
Article in English | MEDLINE | ID: mdl-15178098

ABSTRACT

We are investigating the effects of in vivo exposure of prototypical enzyme inducing agents on hepatic biotransformation enzyme expression in largemouth bass (Micropterus salmoides), a predatory game fish found throughout the United States and Canada. The current study targeted those genes involved in biotransformation and oxidative stress that may be regulated by Ah-receptor-dependent pathways. Exposure of bass to beta-naphthoflavone (beta-NF, 66 mg/kg, i.p.) elicited a 7-9-fold increase in hepatic microsomal cytochrome P4501A-dependent ethoxyresorufin O-deethylase (EROD) activities, but did not affect cytosolic GST catalytic activities toward 1-chloro-2,4-dinitrobenzene (CDNB) or 5-androstene-3,17-dione (ADI). Glutathione S-transferase A (GST-A) mRNA expression exhibited a transient, but non-significant increase following exposure to beta-NF, and generally tracked the minimal changes observed in GST-CDNB activities. Expression of the mRNA encoding glutamate-cysteine ligase catalytic subunit (GCLC), the rate-limiting enzyme in glutathione (GSH) biosynthesis, was increased 1.7-fold by beta-NF. Changes in GCLC mRNA expression were paralleled by increases in intracellular GSH. In summary, largemouth bass hepatic CYP1A-dependent and GSH biosynthetic pathways, and to a lesser extent GST, are responsive to exposure to beta-NF.


Subject(s)
Bass/metabolism , Glutathione/metabolism , RNA, Messenger/metabolism , beta-Naphthoflavone/pharmacokinetics , beta-Naphthoflavone/toxicity , Analysis of Variance , Androstenedione , Animals , Biotransformation/drug effects , Cytochrome P-450 CYP1A1/biosynthesis , DNA Primers , DNA, Complementary/genetics , Dinitrochlorobenzene , Enzyme Induction/drug effects , Glutamate-Cysteine Ligase/biosynthesis , Glutamate-Cysteine Ligase/genetics , Glutathione Transferase/biosynthesis , Glutathione Transferase/genetics , Liver/enzymology , Microsomes/enzymology , Plasmids/genetics , Polymerase Chain Reaction/methods
16.
Comp Biochem Physiol C Toxicol Pharmacol ; 137(3): 237-47, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15171948

ABSTRACT

The effects of in vivo exposure to a natural and synthetic estrogen upon three hepatic phase II enzyme pathways involved in cellular protection against reactive intermediates were investigated in the largemouth bass (Micropterus salmoides). The pathways analyzed included glutathione S-transferases (GST), glutathione (GSH) biosynthesis and NAD(P)H-dependent quinone reductase (QR). Following exposure to 17-beta estradiol (E2, a model natural estrogen; 2 mg/kg, i.p.) or 4-nonylphenol (NP, a model synthetic estrogen; 5 mg/kg and 50 mg/kg, i.p.), serum vitellogenin concentrations in male fish were markedly increased. Exposure to E2 did not affect steady-state GST-A mRNA expression, although GST catalytic activity toward 1-chloro 2,4-dinitrobenzene (CDNB) was elevated at 48 h post-injection. In addition, the rates of bass liver GST-4-hydroxy-2-nonenal (GST-4HNE) conjugation were elevated by E2 exposure at all timepoints. In contrast, exposure to NP decreased steady-state GST-A mRNA levels, but did not alter GST catalytic activities. Hepatic GSH levels were not significantly affected by exposure to either compound, although a trend towards increased GSH biosynthesis was observed with both compounds. Although bass liver quinone reductase catalyzed 2,6-dichloroindophenol (DCP) reduction, unlike in rodents, these catalytic activities were not inhibited by dicoumarol. Exposure to 5 mg/kg NP significantly increased hepatic QR activities. Collectively, our data suggest that exposure to E2 or NP alters the ability of largemouth bass to biotransform environmental chemicals through glutathione S-transferase and quinone reductase catalytic pathways.


Subject(s)
Bass/metabolism , Estradiol/toxicity , Inactivation, Metabolic/physiology , Liver/metabolism , Phenols/toxicity , Animals , Dicumarol/pharmacology , Enzyme Inhibitors/pharmacology , Enzyme-Linked Immunosorbent Assay , Glutathione/biosynthesis , Glutathione Transferase/biosynthesis , Male , NAD(P)H Dehydrogenase (Quinone)/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Subcellular Fractions , Substrate Specificity , Vitellogenins/metabolism
17.
Biochem Pharmacol ; 67(11): 2129-39, 2004 Jun 01.
Article in English | MEDLINE | ID: mdl-15135309

ABSTRACT

We are currently investigating the role of detoxification pathways in protecting against the sublethal effects of chemicals in largemouth bass (Micropterus salmoides). To this end, previous work in our laboratory indicated a remarkable ability of bass liver glutathione S-transferases (GSTs) to detoxify 4-hydroxynonenal (4HNE), a common mutagenic and cytotoxic alpha,beta-unsaturated aldehyde produced during the peroxidation of lipids. In the current study, we observed that GST-mediated 4HNE conjugation in bass liver follows high efficiency single-enzyme Michaelis-Menten kinetics, suggesting that an individual GST isoform is involved in 4HNE detoxification. Using 5' and 3' rapid amplification of cDNA ends (RACE), a full-length GST cDNA of 957 base pairs (bp) in length, containing an open reading frame of 678 bp and encoding a polypeptide of 225 amino acids, has been cloned. Interestingly, a search of the BLAST protein database revealed the presence of homologous GST proteins in the plaice (Pleuronectes platessa), European flounder (Platichthys flesus) and fathead minnow (Pimephales promelas), but not in other fish species. Furthermore, the bass GST protein exhibited little homology with the mammalian GSTA4 subclass of proteins which rapidly metabolize 4HNE. The recombinant 6 x His-tagged expressed GST protein showed high catalytic activity towards 4HNE, while showing moderate or low activity toward other class specific GST substrates. HPLC-GST subunit analysis, followed by sequencing, demonstrated that the isolated bass liver GST subunit constitutes the major GST protein in bass liver, with a molecular mass of 26.4 kDa. In summary, the presence of a highly expressed GST isozyme in bass and several evolutionarily divergent fish species indicates the conservation of an important and distinct detoxification protein that protects against oxidative damage in certain aquatic organisms.


Subject(s)
Glutathione Transferase/genetics , Liver/enzymology , Amino Acid Sequence , Animals , Base Sequence , Bass , Biotransformation , Chromatography, High Pressure Liquid , Cloning, Molecular , DNA, Complementary , Gene Expression , Glutathione Transferase/chemistry , Glutathione Transferase/metabolism , Kinetics , Mass Spectrometry , Molecular Sequence Data , Organ Specificity , Recombinant Proteins/immunology , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Analysis, Protein
18.
J Pers Assess ; 82(1): 104-13, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14979839

ABSTRACT

Research supports the construct validity of the Relationship Profile Test (RPT; Bornstein & Languirand, 2003), a 30-item, self-report measure of destructive overdependence (DO), dysfunctional detachment (DD), and healthy dependency. In this investigation, we assessed the relationships of gender, gender role, and gender role stereotype ratings to RPT subscale scores. In Study 1, we replicated earlier patterns of gender differences in RPT scores, assessed cross-sample consistency in gender difference effect sizes, and provided preliminary nonclinical norms for the RPT subscales. Study 2 showed that--as expected--DO items are perceived as stereotypically feminine, whereas DD items are perceived as stereotypically masculine. In Study 3, we examined the relationships of RPT subscale scores to masculinity, femininity, and androgyny scores. We discuss the theoretical, empirical, and clinical implications of these findings.


Subject(s)
Gender Identity , Interpersonal Relations , Stereotyping , Surveys and Questionnaires , Adolescent , Adult , Female , Humans , Male , Reproducibility of Results
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