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1.
Food Chem Toxicol ; 165: 113137, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35588981

ABSTRACT

Brominated vegetable oil (BVO) has been approved by the US Food and Drug Administration on an interim basis as a food additive. Past studies have raised concerns about potential toxicities from consuming BVO. To investigate further these toxicities, we conducted a 90-day dietary exposure study in Sprague Dawley rats and analyzed tissue distribution of the main metabolites. Six-week-old male and female rats were fed diets containing 0 (control), 0.002%, 0.02%, 0.1%, or 0.5% BVO by weight. Statistically significant increases were observed in the serum bromide in the high-dose group of both sexes and in the incidence of thyroid follicular cell hypertrophy in the two highest dose groups of males and the high-dose group of females. An increase in serum TSH was observed in the high-dose group for both sexes, as well as a decrease in serum T4 in the high-dose males. A clear dose-response was observed in di- and tetra-bromostearic acid levels in the heart, liver, and inguinal fat. These data expand upon previous observations in rats and pigs that oral exposure to BVO is associated with increased tissue levels of inorganic and organic bromine, and that the thyroid is a potential target organ of toxicity.


Subject(s)
Liver , Plant Oils , Animals , Female , Male , Plant Oils/toxicity , Rats , Rats, Sprague-Dawley , Swine , Tissue Distribution
2.
Food Chem Toxicol ; 132: 110728, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31365888

ABSTRACT

We report the data from the guideline-compliant two-year toxicology study conducted as part of the Consortium Linking Academic and Regulatory Insights on Bisphenol A Toxicity (CLARITY-BPA). BPA (0, 2.5, 25, 250, 2,500, and 25,000 µg/kg body weight (bw)/day) was administered daily by gavage in 0.3% carboxymethylcellulose vehicle to NCTR Sprague-Dawley rats from gestation day 6 through the start of parturition and then directly to pups from the day after birth until postnatal day 21 (stop-dose arm) or continuously until termination at one or two years. The stop-dose arm was included to assess the potential for any BPA effects that were due to developmental exposure. No BPA-related effects were evident in the in-life and non-histopathology data. Neoplastic and nonneoplastic lesions diagnosed in both females and males were common age-associated lesions that were variable across control and BPA-treated groups. The lack of consistent responses within the continuous- and stop-dose arms within and across tissues brought into question the plausible relationship of most of these lesions to BPA treatment. There was a possible relationship between the increased incidences of lesions in the female reproductive tract and the male pituitary and exposure to the 25,000 µg BPA/kg bw/day dose level.


Subject(s)
Benzhydryl Compounds/toxicity , Endocrine Disruptors/toxicity , Phenols/toxicity , Animals , Dose-Response Relationship, Drug , Ethinyl Estradiol/administration & dosage , Female , Genitalia, Female/drug effects , Male , Maternal Exposure , Pregnancy , Rats , Rats, Sprague-Dawley
4.
Epidemiol Infect ; 144(13): 2728-31, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27586030

ABSTRACT

Two cases of hospital-acquired listeriosis were linked to a commercially produced, pasteurized ice cream mix. Manufacturers should implement safety measures from the Food Safety Modernization Act to minimize the risk of Listeria contamination. Dietary guidelines for persons at high risk of listeriosis may need revision to recognize the potential risk from pasteurized products.


Subject(s)
Cross Infection/microbiology , Food Microbiology , Foodborne Diseases/microbiology , Ice Cream/microbiology , Listeria monocytogenes/isolation & purification , Listeriosis/microbiology , Humans , Male , Middle Aged , Pasteurization , Washington
5.
Head Neck Pathol ; 10(3): 405-13, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27075025

ABSTRACT

We present the second reported mammary analog secretory carcinoma (MASC) apparently arising in the thyroid and propose a potential close relationship to ETV6-NTRK3 fusion papillary thyroid carcinoma. The patient, a 36 year old woman, presented with a neck mass of 1 year's duration. Imaging studies showed a tumor involving most of the thyroid with enlarged regional lymph nodes. FNA biopsy yielded a diagnosis of "papillary thyroid carcinoma". Resection revealed a 4.5 cm infiltrative tumor. Final diagnosis was "papillary thyroid carcinoma (PTC) consistent with diffuse sclerosing variant" with positive lymph nodes (2+/4) and margins. Histologic features included mixed microcystic, solid, follicular and papillary architecture, prominent nucleoli, abundant nuclear grooves and rare nuclear pseudo-inclusions. Despite radioactive iodine, radiotherapy and multiagent chemotherapy, the patient progressed over 6 years with local recurrence and additional lymph node involvement finally developing widespread distant metastases. Prompted by the breast carcinoma-like histopathology of a metastasis, immunohistochemical staining was performed and revealed strong expression of GATA3 and mammaglobin with no reactivity for thyroglobulin or TTF-1. The original tumor was then tested and showed the same immunoprofile. RT-PCR confirmed the presence of an ETV6-NTRK3 fusion consistent with a diagnosis of MASC. Our patient's clinical, imaging and morphologic features remarkably mimicked papillary thyroid carcinoma. At the molecular level, the ETV6-NTRK3 fusion in this patient involved exons reported in the rare "papillary thyroid carcinoma" with this translocation. Given the immunophenotype of this case, it is possible that at least some ETV6-NTRK3 fusion positive PTC are actually MASC masquerading as papillary thyroid carcinoma.


Subject(s)
Biopsy, Fine-Needle , Carcinoma/diagnosis , Diagnostic Errors , Mammary Analogue Secretory Carcinoma/diagnosis , Thyroid Neoplasms/diagnosis , Adult , Biomarkers, Tumor/analysis , Carcinoma/genetics , Carcinoma, Papillary , Female , Humans , Immunohistochemistry , Mammary Analogue Secretory Carcinoma/genetics , Oncogene Proteins, Fusion/genetics , Reverse Transcriptase Polymerase Chain Reaction , Thyroid Cancer, Papillary , Thyroid Neoplasms/genetics
6.
Clin Obes ; 5(6): 333-41, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26434773

ABSTRACT

The objective of this study was to evaluate health outcomes and costs of pregnancies complicated by extreme maternal obesity (class III obesity, body mass index ≥ 40). We conducted a retrospective case-control descriptive study comparing extremely obese women (cases) and their infants with randomly selected controls. Health outcomes were obtained from the medical records and costs from billing data. Total costs for each mother-infant dyad were calculated. Compared with 85 controls, the 82 cases experienced higher morbidity, higher costs and prolonged hospital stay. However, 26% of cases maintained or lost weight during pregnancy, whereas none of the controls maintained or lost weight during pregnancy. When mother/infant dyads were compared on costs, case subjects who maintained or lost weight experienced lower costs than those who gained weight. Neonatal intensive care consumed 78% of total hospital costs for infants of the obese women who gained weight, but only 48% of costs for infants of obese women who maintained or lost weight. For extremely obese women, weight management during pregnancy was achievable, resulted in healthier neonatal outcomes and reduced perinatal healthcare costs.


Subject(s)
Hospital Costs , Mothers , Obesity, Morbid/economics , Obesity, Morbid/therapy , Pregnancy Complications/economics , Pregnancy Complications/therapy , Adult , Body Mass Index , Female , Humans , Infant, Newborn , Intensive Care, Neonatal/economics , Length of Stay , Obesity, Morbid/complications , Pregnancy , Pregnancy Outcome , Retrospective Studies , United States , Weight Gain , Weight Loss
7.
J Clin Pediatr Dent ; 32(1): 69-72, 2007.
Article in English | MEDLINE | ID: mdl-18274475

ABSTRACT

Recognition of "Jobs Syndrome" disorder may lead to better care. One of the dental manifestations reported is a high arched palate. Measurements of the maxillary arch were made to compare affected Job's patients, unaffected family members, and controls. Measurements of the palate found little difference between the three groups. DMFS, periodontal disease, and oral hygiene were evaluated with little difference between groups.


Subject(s)
Dental Arch/anatomy & histology , Job Syndrome/pathology , Oral Hygiene , Palate/anatomy & histology , Periodontal Diseases/complications , Adolescent , Adult , Case-Control Studies , Cephalometry , Child , Female , Humans , Job Syndrome/complications , Male , Maxilla/anatomy & histology , Oral Hygiene Index , Reference Values
8.
Science ; 309(5741): 1677; author reply 1677, 2005 Sep 09.
Article in English | MEDLINE | ID: mdl-16150996
9.
J Matern Fetal Neonatal Med ; 15(5): 297-301, 2004 May.
Article in English | MEDLINE | ID: mdl-15280119

ABSTRACT

OBJECTIVE: The study was conducted to investigate whether the strength of uterine contractions monitored invasively by intrauterine pressure catheter could be determined from transabdominal electromyography (EMG) and to estimate whether EMG is a better predictor of true labor compared to tocodynamometry (TOCO). STUDY DESIGN: Uterine EMG was recorded from the abdominal surface in laboring patients simultaneously monitored with an intrauterine pressure catheter (n = 13) or TOCO (n = 24). Three to five contractions per patient and corresponding electrical bursts were randomly selected and analyzed (integral of intrauterine pressure; integral, frequency, amplitude of contraction curve on TOCO; burst energy for EMG). The Mann-Whitney test, Spearman correlation and receiver operator characteristics (ROC) analysis were used as appropriate (significance was assumed at a value of p < 0.05). RESULTS: EMG correlated strongly with intrauterine pressure (r = 0.764; p = 0.002). EMG burst energy levels were significantly higher in patients who delivered within 48 h compared to those who delivered later (median [25%/75%]: 96,640 [26,520-322,240] vs. 2960 [1560-10,240]; p < 0.001), whereas none of the TOCO parameters were different. In addition, burst energy levels were highly predictive of delivery within 48 h (AUC = 0.9531; p < 0.0001). CONCLUSION: EMG measurements correlated strongly with the strength of contractions and therefore may be a valuable alternative to invasive measurement of intrauterine pressure. Unlike TOCO, transabdominal uterine EMG can be used reliably to predict labor and delivery.


Subject(s)
Electromyography/methods , Labor, Obstetric/physiology , Uterine Contraction/physiology , Uterine Monitoring/methods , Abdomen , Female , Humans , Predictive Value of Tests , Pregnancy , ROC Curve
10.
Appl Microbiol Biotechnol ; 63(3): 249-57, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14566430

ABSTRACT

This review describes the historical development and current state of metals leaching and sulfide mineral biooxidation by the minerals industries. During the past 20 years commercial processes employing microorganisms for mineral recovery have progressed from rather uncontrolled copper dump leaching to mineral oxidation and leaching in designed bioheaps for oxidation of refractory gold ores and for copper recovery. Also during this period of time, stirred tank bioleaching has been commercialized for cobalt recovery and for biooxidation of refractory gold ores. Chalcopyrite bioleaching in stirred tanks is on the verge of commercialization. Commercial applications of biohydrometallurgy have advanced due to favorable process economics and, in some cases, reduced environmental problems compared to conventional metal recovery processes such as smelting. Process development has included recognition of the importance of aeration of bioheaps, and improvements in stirred tank reactor design and operation. Concurrently, knowledge of the key microorganisms involved in these processes has advanced, aided by advances in molecular biology to characterize microbial populations.


Subject(s)
Bacteria/metabolism , Industrial Microbiology/trends , Minerals/metabolism , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Industrial Microbiology/methods , Oxidation-Reduction
11.
J Matern Fetal Neonatal Med ; 13(4): 242-5, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12854924

ABSTRACT

OBJECTIVE: To determine whether using color flow Doppler to identify the umbilical cord affects amniotic fluid index (AFI) measurements. METHODS: A total of 2236 AFI measurements between 24 and 42 weeks in singleton gestations with no known or suspected fetal anomalies and < 14 days' discrepancy between menstrual and ultrasonographic dating were included. Color flow Doppler was used to identify loops of umbilical cord; these were excluded from the measurement. Polynomial regression was used to generate means and centiles. Data were grouped according to completed weeks of gestation and descriptive statistics were calculated. At each week of gestation, the number and percentage of pregnancies diagnosed as < or = 2.5th, < or = 5th, > or = 95th, and > or = 97.5th centile according to a 'standard' nomogram derived without using color flow Doppler were calculated. RESULTS: The AFI decreased significantly over gestational age, starting at 31 weeks (p < 0.05 by ANOVA). The relationship between AFI and gestational age was best modeled by a second-degree polynomial (p < 0.001). The median and range of the proportion of AFIs that fell outside the ranges of the standard nomogram at each completed gestational age was: 6.0 (2.3-35.4)% for the < or = 2.5th centile, 9.9 (3.1-37.5)% for the < or = 5th centile, 3.8 (0-30)% for the > or = 95th centile, and 1.8 (0-20)% for the > or = 97.5th centile. The 2.5th and 5th centiles using the current data were lower than those of the 'standard', and the difference increased with advancing gestation. Upper centiles were also different. CONCLUSION: The AFI measured using color flow Doppler overestimates oligohydramnios and may underestimate polyhydramnios when a standard AFI table obtained without color flow Doppler is used. Normal values specific for measurement method should be used for reference.


Subject(s)
Amniotic Fluid/diagnostic imaging , Ultrasonography, Doppler, Color , False Negative Reactions , False Positive Reactions , Female , Gestational Age , Humans , Oligohydramnios/diagnostic imaging , Polyhydramnios/diagnostic imaging , Pregnancy , Reference Values , Umbilical Cord/diagnostic imaging
12.
J Soc Gynecol Investig ; 9(5): 265-75, 2002.
Article in English | MEDLINE | ID: mdl-12383910

ABSTRACT

OBJECTIVE: Understanding the physiology of the uterus and cervix during term and preterm parturition is crucial for developing methods to control their function and is essential to solving clinical problems related to labor. To date, only crude, inaccurate, and subjective methods are used to assess changes in uterine and cervical function in pregnancy. METHODS: In the past several years, we have developed noninvasive methods to quantitatively evaluate the uterus and cervix based on recording of uterine electrical signals from the abdominal surface (uterine electromyography) and measurement of light-induced fluorescence (LIF) of cervical collagen (Collascope), respectively. Both methods are rapid and allow immediate assessment of uterine contractility and cervical ripening. RESULTS: Studies in animals and humans indicated that uterine and cervical performance can be monitored successfully during pregnancy using those approaches and that these techniques can be used during labor to better define management in a variety of conditions associated with labor. CONCLUSION: The potential benefits of the proposed instrumentation and methods include reducing the rate of preterm delivery, improving maternal and perinatal outcome, monitoring treatment, decreasing cesarean rate and providing research methods to understand uterine and cervical function.


Subject(s)
Electromyography , Fluorescence , Labor, Obstetric , Obstetric Labor, Premature/physiopathology , Uterus/physiopathology , Animals , Cervix Uteri/chemistry , Cervix Uteri/physiopathology , Collagen/chemistry , Female , Humans , Light , Myometrium/physiopathology , Obstetric Labor, Premature/prevention & control , Pregnancy , Spectrometry, Fluorescence , Uterine Contraction
13.
Biotechniques ; 32(5): 1168, 1170-2, 1174 passim, 2002 May.
Article in English | MEDLINE | ID: mdl-12019791

ABSTRACT

Transcription factor-DNA interactions have been widely studied in the regulation of gene expression. We have established an enzyme-linked immunoassay platform to quantify specific transcriptionfactor-DNA interactions. In our assay, dsDNA immobilized on a 96-well plate captures the transcriptionfactor from the nuclear extract of mammalian cells. The DNA-bound transcription factor is detected and quantified by enzyme-linked immunoassay using a transcription factor-specific antibody. We have profiled multiple transcription factors involved in inflammation including NFkappaB p50, NFkappaB p65, c-Rel, c-Fos, CREB-1, and ATF-2. When compared with the traditional electrophoretic mobility shift assay, the enzyme-linked immunoassay shows a 10-fold higher sensitivity, eliminates the use of radioactivity, allows for a high-throughput format, and is faster.


Subject(s)
Immunoenzyme Techniques/methods , Transcription Factors/genetics , Activating Transcription Factor 2 , Animals , Antibody Specificity , Base Sequence , Cell Extracts , Cell Nucleus , Consensus Sequence , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/immunology , Cyclic AMP Response Element-Binding Protein/metabolism , DNA/genetics , DNA/metabolism , HeLa Cells , Humans , Jurkat Cells , Mammals , NF-kappa B/genetics , NF-kappa B/immunology , NF-kappa B/metabolism , NF-kappa B p50 Subunit , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-fos/immunology , Proto-Oncogene Proteins c-fos/metabolism , Sensitivity and Specificity , Transcription Factors/immunology , Transcription Factors/metabolism
14.
Life Sci ; 69(23): 2765-73, 2001 Oct 26.
Article in English | MEDLINE | ID: mdl-11720081

ABSTRACT

Leptin regulates body adiposity by decreasing feeding and increasing thermogenesis. Obese humans and some obese rodents are resistant to peripherally administered leptin, suggesting a defect in the transport of leptin across the blood-brain barrier (BBB). Defective transport of exogenous leptin occurs in some models of obesity, but in other models transport is normal. This shows that factors other than obesity are associated with impairment of leptin transport across the BBB. In order to further investigate these factors, we determined leptin transport in rats made obese by lesioning of the ventromedial hypothalamus (VMH), paraventricular nucleus (PVN), or posterodorsal amygdala (PDA). These regions all contain leptin receptors and lesions there induce obesity and hyperleptinemia and alter the levels of many feeding hormones which might participate in leptin transporter regulation. We measured the uptake of radioactively labeled leptin by the BBB by multiple-time regression analysis which divides uptake into a reversible phase (Vi, e.g., receptor/transporter binding to the brain endothelial cell) and an irreversible phase (Ki, complete transport across the BBB). Leptin uptake was not affected in rats with VMH lesions. No significant change occurred in the entry rate (Ki) for any group, although Ki declined by over 35% in rats with PVN lesions. Decreased uptake was observed in rats with PVN lesions and with PDA lesions. This was primarily due to a reduced Vi (about 21% for the PDA). This decreased uptake is most likely explained by decreased binding of leptin to the brain endothelial cell, which could be because of decreased binding by either receptors or transporters. This suggests that some of the feeding hormones controlled by the PVN and PDA may participate in regulating leptin uptake by the BBB.


Subject(s)
Amygdala/metabolism , Blood-Brain Barrier/physiology , Hypothalamus/metabolism , Leptin/metabolism , Obesity/metabolism , Paraventricular Hypothalamic Nucleus/metabolism , Amygdala/injuries , Animals , Female , Hypothalamus/injuries , Obesity/etiology , Paraventricular Hypothalamic Nucleus/injuries , Rats , Rats, Long-Evans , Weight Gain
15.
Otolaryngol Head Neck Surg ; 125(3): 213-20, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11555756

ABSTRACT

OBJECTIVES: Lymphoscintigraphy with sentinel node dissection and 18 fluoro-2-deoxyglucose positron emission tomography (PET) are being used independently in the management of many intermediate and thick melanomas of the head and neck. We report a series of patients with melanoma of the head and neck with Breslow depths greater than 1.0 mm and clinically negative regional nodes that were evaluated prospectively with PET and lymphoscintigraphy. STUDY DESIGN AND SETTING: Between July 1, 1998 and December 30, 2000 PET scans were obtained preoperatively on 18 patients undergoing resection of head and neck melanoma. Lymphoscintigraphy and sentinel node dissection was performed. Resection of the primary lesion was then carried out with adequate margins and the defects were reconstructed. RESULTS: Sentinel node(s) were found in 17/18 patients (94.4%); 5/18 (27.8%) of cases had metastases. PET detected nodal metastasis preoperatively in 3 patients (16.7%), one of which had a positive sentinel node dissection. CONCLUSION: PET and lymphoscintigraphy offer complimentary ways of evaluation for metastatic melanoma.


Subject(s)
Head and Neck Neoplasms/diagnostic imaging , Lymph Nodes/diagnostic imaging , Melanoma/diagnostic imaging , Sentinel Lymph Node Biopsy , Tomography, Emission-Computed , Aged , Aged, 80 and over , Female , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/therapy , Humans , Lymphatic Metastasis/diagnosis , Male , Melanoma/pathology , Melanoma/therapy , Middle Aged , Nose Neoplasms/diagnostic imaging
16.
Drug Des Discov ; 17(3): 191, 2001.
Article in English | MEDLINE | ID: mdl-11469749

Subject(s)
Drug Design
17.
J Ind Microbiol Biotechnol ; 26(3): 134-9, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11420652

ABSTRACT

Chromobacterium violaceum is a cyanogenic (cyanide-producing) microorganism. Cyanide is used on an industrial scale to complex and recover gold from ores or concentrates of ores bearing the precious metal. A potentially useful approach in gold mining operations could be to produce cyanide biologically in relatively small quantities at the ore surface. In this study, C. violaceum grown in nutrient broth formed a biofilm and could complex and solubilize 100% of the gold on glass test slides within 4-7 days. Approximately 50% of the cyanide- recoverable gold could be mobilized from a biooxidized sulfidic-ore concentrate. Complexation of cyanide in solution by gold appeared to have a beneficial effect on cell growth--viable cell counts were nearly two orders of magnitude greater in the presence of gold-coated slides or biooxidized ore substrates than in their absence. C. violaceum was cyanogenic when grown in alternative feedstocks. When grown in a mineral salt solution supplemented with 13.3% v/v swine fecal material (SFM), cells exhibited pigmentation and suspended cell concentrations comparable to cultures grown in nutrient broth. Glycine supplements stimulated production of cyanide in 13.3% v/v SFM. In contrast, glycine was inhibitory when added at the time of inoculation in the more concentrated SFM, decreasing cell numbers and reducing ultimate bulk-solution cyanide concentrations. However, aeration and addition of glycine to stationary phase cells grown on 13.3% v/v SFM anaerobically resulted in rapid production and high concentrations (up to 38 mg l(-1)) of cyanide. This indicates that biogenesis of cyanide may be supported in remote areas using locally produced and inexpensive agricultural feedstocks in place of commercial media.


Subject(s)
Chromobacterium/metabolism , Cyanides/metabolism , Gold/chemistry , Gold/isolation & purification , Animals , Biofilms , Biotechnology/methods , Chromobacterium/growth & development , Culture Media/chemistry , Cyanides/chemistry , Feces , Gold/metabolism , Swine
18.
Int J Toxicol ; 20(2): 59-67, 2001.
Article in English | MEDLINE | ID: mdl-11354467

ABSTRACT

The chronic toxicity of 1,3,5-trinitrobenzene (TNB) in male and female Fischer 344 (F344) rats was evaluated by feeding a diet containing 0, 5, 60, and 300 ppm of TNB for 2 years. The calculated average TNB intake over 2 years for males and females was 0.22, 2.64, 13.44 and 0.23, 2.68, 13.31 mg/kg body weight (BW)/day respectively. Terminal body weights were decreased and water intake was increased in both sexes (300 ppm), whereas food consumption was decreased in males (60 and 300 ppm groups) only. The relative spleen weights were significantly decreased in both sexes (300 ppm), whereas the relative brain weights were increased in females only (300 ppm). Hematological effects were not observed in animals killed at the 2-year time point, except significant decrease in the mean corpuscular hemoglobin (MCH) in males (300 ppm) and in females (60 and 300 ppm). Methemoglobin levels were increased in both sexes in the high dose group. Histopathological examination showed treatment-related changes in the kidney (hyaline droplets; 60 and 300 ppm) and the spleen (erythroid cell hyperplasia and pigment deposition; 300 ppm) of both sexes. Cytoplasmic hyaline droplets in the kidneys were characterized by immunohistochemistry as alpha-2mu-globulin. We propose a chronic, oral no-observable-adverse-effect level (NOAEL) of 2.68 mg/kg BW/day for TNB in the rat, based on the hematological and renal changes.


Subject(s)
Trinitrobenzenes/toxicity , Water Pollutants, Chemical/toxicity , Administration, Oral , Alpha-Globulins , Animals , Body Weight/drug effects , Brain/drug effects , Brain/pathology , Diet , Dose-Response Relationship, Drug , Drinking/drug effects , Eating/drug effects , Erythrocyte Indices/drug effects , Female , Kidney Cortex/drug effects , Kidney Cortex/pathology , Male , Methemoglobin/drug effects , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Inbred F344 , Spleen/drug effects , Spleen/pathology , Trinitrobenzenes/administration & dosage , Water Pollutants, Chemical/administration & dosage
20.
J Biol Chem ; 276(20): 17332-8, 2001 May 18.
Article in English | MEDLINE | ID: mdl-11278869

ABSTRACT

The cAMP-dependent protein kinase (PKA) is targeted to specific subcellular compartments through its interaction with A-kinase anchoring proteins (AKAPs). AKAPs contain an amphipathic helix domain that binds to the type II regulatory subunit of PKA (RII). Synthetic peptides containing this amphipathic helix domain bind to RII with high affinity and competitively inhibit the binding of PKA with AKAPs. Addition of these anchoring inhibitor peptides to spermatozoa inhibits motility (Vijayaraghavan, S., Goueli, S. A., Davey, M. P., and Carr, D. W. (1997) J. Biol. Chem. 272, 4747-4752). However, inhibition of the PKA catalytic activity does not mimic these peptides, suggesting that the peptides are disrupting the interaction of AKAP(s) with proteins other than PKA. Using the yeast two-hybrid system, we have now identified two sperm-specific human proteins that interact with the amphipathic helix region of AKAP110. These proteins, ropporin (a protein previously shown to interact with the Rho signaling pathway) and AKAP-associated sperm protein, are 39% identical to each other and share a strong sequence similarity with the conserved domain on the N terminus of RII that is involved in dimerization and AKAP binding. Mutation of conserved residues in ropporin or RII prevents binding to AKAP110. These data suggest that sperm contains several proteins that bind to AKAPs in a manner similar to RII and imply that AKAPs may have additional and perhaps unique functions in spermatozoa.


Subject(s)
Adaptor Proteins, Signal Transducing , Carrier Proteins/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclic AMP/metabolism , Membrane Proteins , A Kinase Anchor Proteins , Amino Acid Sequence , Animals , Binding Sites , Carrier Proteins/chemistry , Carrier Proteins/genetics , Cyclic AMP-Dependent Protein Kinase Type II , Cyclic AMP-Dependent Protein Kinases/chemistry , Dimerization , Humans , Male , Mice , Molecular Sequence Data , Protein Structure, Secondary , Protein Subunits , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Spermatozoa/metabolism , rho GTP-Binding Proteins/chemistry , rho GTP-Binding Proteins/metabolism
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