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Flannery C, Shea C, O’Brien Y, O’Halloran J, Matvienko-Sikar K, Kelly C, Toomey E. Investigating group-based classes ('weaning workshops') to support complementary infant feeding in Irish primary care settings: a cross-sectional survey. Public Health Nutr 2022; 25:1-12. [PMID: 35260219 PMCID: PMC9991655 DOI: 10.1017/s1368980022000477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE This study aims to (1) investigate current practice regarding 'weaning workshops' to support complementary infant feeding delivered within Irish primary care, (2) explore the experiences and opinions of community dietitians regarding optimal content and modes of delivery of weaning workshops and (3) identify the key factors to be considered in the development and implementation of weaning workshops delivered within primary care. DESIGN Cross-sectional survey. SETTING Irish primary care. PARTICIPANTS Forty-seven community-based dietitians. RESULTS Sixteen dietitians reported that workshops were run in their area with variable frequency, with ten reporting that workshops were never run in their area. Participants reported that mostly mothers of medium socio-economic status (SES) attended weaning workshops when infants were aged between 4 and 7 months, and that feedback from workshop attendees was predominantly positive. Dietitians identified that key factors to be considered in future development and delivery of weaning workshops are (1) workshop characteristics such as content, timing and venue, (2) organisational characteristics such as availability of resources and multidisciplinary involvement and (3) attendee characteristics such as SES. CONCLUSIONS This study highlights substantial variability regarding provision of weaning workshops in Ireland, and a lack of standardisation regarding the provider, content and frequency of workshops where workshops are being delivered. The study also provides unique insights into the experiences and opinions of primary care community dietitians regarding the development and delivery of weaning workshops in terms of optimal content and delivery options. These perspectives will make a valuable contribution given the dearth of evidence in this area internationally.
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Affiliation(s)
- Caragh Flannery
- School of Public Health, University College Cork, CorkT12 K8AF, Ireland
- INFANT Centre, Cork University Maternity Hospital, University College Cork, Cork, Ireland
| | - Caroline Shea
- School of Public Health, University College Cork, CorkT12 K8AF, Ireland
| | - Yvonne O’Brien
- Community Nutrition and Dietetic Service, Cork Kerry Community Healthcare, HSE, Cork, Ireland
| | - Joanne O’Halloran
- Primary Care Centre, Mountkennedy Town Centre, Newtownmountkennedy, Co Wicklow, Ireland
| | | | - Colette Kelly
- Health Promotion Research Centre, National University of Ireland Galway, Galway, Ireland
| | - Elaine Toomey
- School of Allied Health, University of Limerick, Co. Limerick, Ireland
- Health Research Institute, University of Limerick, Co. Limerick, Ireland
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Ma SL, Chen LH, Lee CC, Lai KYC, Hung SF, Tang CP, Ho TP, Shea C, Mo F, Mak TSH, Sham PC, Leung PWL. Genetic Overlap Between Attention Deficit/Hyperactivity Disorder and Autism Spectrum Disorder in SHANK2 Gene. Front Neurosci 2021; 15:649588. [PMID: 33986640 PMCID: PMC8111170 DOI: 10.3389/fnins.2021.649588] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Recent findings indicated a high comorbidity between attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), as well as shared genetic influences on them. The latter might contribute at least partly to the former clinical scenario. This study aimed at investigating whether SHANK genes were potential pleiotropic genes to the two said disorders, underlying their genetic overlap. Methods: This study recruited 298 boys with ADHD (including 256 family trios of 1 ADHD boy and his 2 biological parents), 134 boys with ASD, 109 boys with both ADHD and ASD, and 232 typically developing boys as community controls. They were aged between 6 and 11 years old. Results: There was no significant difference in allele frequency of a number of single nucleotide polymorphisms (SNPs) in SHANK2/SHANK3 between the three clinical groups (ADHD, ASD, and ADHD + ASD) and between the two control groups (community controls and pseudo-controls), respectively. The three clinical groups and the two control groups were thus, respectively, combined. A comparison between the two aggregated samples identified significant evidence of disease association for three SHANK2 SNPs with both ADHD and ASD, even after multiple testing correction: rs11236616 (OR = 0.762, permuted p = 0.0376), rs7106631 (OR = 0.720, permuted p = 0.0034), and rs9888288 (OR = 0.770, permuted p = 0.0407). Comparisons among individual groups pointed to a similar trend of findings. Conclusion:SHANK2 could be considered a potential pleiotropic gene underlying the genetic overlap between ADHD and ASD. This might contribute partly to their high comorbidity in the afflicted children.
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Affiliation(s)
- Suk-Ling Ma
- Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong, China
| | - Lu Hua Chen
- Centre for PanorOmic Sciences - Genomics and Bioinformatics Cores, The University of Hong Kong, Hong Kong, China.,Department of Psychology, The Chinese University of Hong Kong, Hong Kong, China
| | - Chi-Chiu Lee
- Kwai Chung Hospital, Hospital Authority, Hong Kong, China
| | - Kelly Y C Lai
- Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong, China
| | - Se-Fong Hung
- Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong, China
| | - Chun-Pan Tang
- Kwai Chung Hospital, Hospital Authority, Hong Kong, China
| | - Ting-Pong Ho
- Department of Psychiatry, The University of Hong Kong, Hong Kong, China
| | - Caroline Shea
- Alice Ho Miu Ling Nethersole Hospital, Hospital Authority, Hong Kong, China
| | - Flora Mo
- Alice Ho Miu Ling Nethersole Hospital, Hospital Authority, Hong Kong, China
| | - Timothy S H Mak
- Centre for PanorOmic Sciences - Genomics and Bioinformatics Cores, The University of Hong Kong, Hong Kong, China
| | - Pak-Chung Sham
- Centre for PanorOmic Sciences - Genomics and Bioinformatics Cores, The University of Hong Kong, Hong Kong, China.,Department of Psychiatry, The University of Hong Kong, Hong Kong, China
| | - Patrick W L Leung
- Department of Psychology, The Chinese University of Hong Kong, Hong Kong, China
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Qiang L, Sample A, Shah P, Shea C, Soltani K, Macleod K, He Y. 1168 Autophagy pathways regulate UV-induced skin tumorigenesis through promoting protumorigenic inflammatory microenvironment. J Invest Dermatol 2018. [DOI: 10.1016/j.jid.2018.03.1182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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Qiang L, Sample A, Shea C, Soltani K, Macleod K, He Y. 751 Autophagy regulates ultraviolet radiation-induced inflammation and skin tumorigenesis. J Invest Dermatol 2017. [DOI: 10.1016/j.jid.2017.02.775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sweeney E, Shinohara R, Shea C, Reich D, Crainiceanu C. Lesion Incidence Estimation and Detection Using Multi-Modality Longitudinal MRIs (P03.069). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p03.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
Nasal cysts representing cystic extension of the nasolacrimal duct are a rare cause of nasal obstruction and respiratory distress in neonates. A medial canthal mass, epiphora, dacryocystitis or preseptal/orbital cellulitis are the usual presenting symptoms; however, this case shows that patients may present with eye findings so minimal as to be overlooked.
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Affiliation(s)
- Heather Varnell
- Departments of Pediatric, The University of Colorado Health Sciences Center, The Children's Hospital, Denver, CO 80218, USA
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Gerasimov MR, Ferrieri RA, Schiffer WK, Logan J, Gatley SJ, Gifford AN, Alexoff DA, Marsteller DA, Shea C, Garza V, Carter P, King P, Ashby CR, Vitkun S, Dewey SL. Study of brain uptake and biodistribution of [11C]toluene in non-human primates and mice. Life Sci 2002; 70:2811-28. [PMID: 12269385 DOI: 10.1016/s0024-3205(02)01542-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inhalant abuse is a rapidly growing health problem particularly among adolescents. Yet we know little about the neural mechanisms underlying the abuse liability of inhalants, particularly when compared to other addictive drugs. Specifically, our understanding of the relationship between the regional brain phamacokinetics and features classically associated with drug reinforcement is lacking. Under the hypothesis that the abuse liability of toluene can be related to its pharmacokinetic properties and the pattern of regional brain uptake, we developed the methodology for radiolabeling and purifying [11C]toluene for use in PET studies. Here we report the regional brain distribution and kinetics of the widely abused solvent toluene in non-human primates and the whole body biodistribution in mice. To our knowledge, this is the first reported study of the in vivo brain pharmacokinetics of labeled toluene in non-human primates. Rapid uptake of radioactivity into striatal and frontal regions was followed by rapid clearance from the brain. Concurrent findings in rodents indicate similar radio-tracer kinetics, with excretion through kidneys and liver. Taken together, our data provides insight into pharmacokinetic features possibly associated with the abuse liability of toluene.
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Affiliation(s)
- M R Gerasimov
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
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Abstract
This study examined individuad differences in the preference for and effectiveness of the type of attentional focus for motor learning. In two experiments, participants practicing a balance task (stabilometer) were asked to find out whether focusing on their feet (internal focus) or on two markets in front of their feet (external focus) was more effective. In Experiment 1, participants switched their attentional focus from trial to trial on Day 1 and used their preferred attentional focus on Day 2. In Experiment 2, participants were free to switch their attentional focus any time during 2 days of practice. Retention tests were performed on Day 3. Most participants chose an external focus. Also, they were more effective in retention than participants who preferred an internal focus.
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Affiliation(s)
- G Wulf
- Department of Kinesiology at the University of Nevada-Las Vegas, 89154-3034, USA.
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Fowler JS, Ding YS, Logan J, MacGregor RR, Shea C, Garza V, Gimi R, Volkow ND, Wang GJ, Schlyer D, Ferrieri R, Gatley SJ, Alexoff D, Carter P, King P, Pappas N, Arnett CD. Species differences in [11C]clorgyline binding in brain. Nucl Med Biol 2001; 28:779-85. [PMID: 11578898 DOI: 10.1016/s0969-8051(01)00245-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
[11C]Clorgyline selectively binds to MAO A in the human brain. This contrasts with a recent report that [11C]clorgyline (in contrast to other labeled MAO A inhibitors) is not retained in the rhesus monkey brain [4]. To explore this difference, we compared [11C]clorgyline in the baboon brain before and after clorgyline pretreatment and we also synthesized deuterium substituted [11C]clorgyline (and its nor-precursor) for comparison. [11C]Clorgyline was not retained in the baboon brain nor was it influenced by clorgyline pretreatment or by deuterium substitution, contrasting to results in humans. This suggests a species difference in the susceptibility of MAO A to inhibition by clorgyline and represents an unusual example of where the behavior of a radiotracer in the baboon brain does not predict its behavior in the human brain.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, New York 11973, USA.
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Fowler JS, Volkow ND, Logan J, Franceschi D, Wang GJ, MacGregor R, Shea C, Garza V, Pappas N, Carter P, Netusil N, Bridge P, Liederman D, Elkashef A, Rotrosen J, Hitzemann R. Evidence that L-deprenyl treatment for one week does not inhibit MAO A or the dopamine transporter in the human brain. Life Sci 2001; 68:2759-68. [PMID: 11400918 DOI: 10.1016/s0024-3205(01)01079-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this study, we investigated whether treatment with L-deprenyl, a selective monoamine oxidase B (MAO B) inhibitor, also inhibits MAO A or the dopamine transporter in the human brain. Six normal volunteers (age 46+/-6 yrs) had two PET sessions, one at baseline and one following L-deprenyl (10 mg/day) for 1 week. Each session included one scan with [11C]clorgyline (to assess MAO A) and one scan 2 hours later with [11C]cocaine (to assess dopamine transporter availability). A 3-compartment model was used to compare the plasma-to-brain transfer constant, K1 (a function of blood flow) and lambdak3 (a kinetic term proportional to brain MAO A) before and after treatment. Dopamine transporter availability was measured as the ratio of distribution volumes of the striatum to cerebellum (DVR) which is equal to Bmax/KD +1. L-Deprenyl treatment for 1 week did not affect either brain MAO A activity or dopamine transporter availability. There was a non-significant trend for an increase in K1 after L-deprenyl. These results confirm that L-deprenyl after one week of treatment at doses typically used clinically is selective for MAO B and that it does not produce a measurable affect on the dopamine transporter, suggesting that MAO A inhibition and dopamine transporter blockade do not contribute to its pharmacological effects.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, NY 11973, USA.
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Fowler JS, Wang GJ, Volkow ND, Franceschi D, Logan J, Pappas N, Shea C, MacGregor RR, Garza V. Maintenance of brain monoamine oxidase B inhibition in smokers after overnight cigarette abstinence. Am J Psychiatry 2000; 157:1864-6. [PMID: 11058487 DOI: 10.1176/appi.ajp.157.11.1864] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The authors' goal was to replicate a previous finding that smokers have lower brain monoamine oxidase B (MAO-B) levels than comparison nonsmoking subjects and to determine if levels recover after overnight cigarette abstinence. METHOD Brain MAO-B levels were measured by means of positron emission tomography in six smokers who were scanned twice: 11.3 hours (baseline) and 10 minutes after smoking one cigarette. RESULTS Average MAO-B levels in smokers in the present study were similar to those found in the previous study and averaged 39% (SD=17) lower than those found in a comparison group of nonsmokers. Brain MAO-B levels did not differ between baseline levels and 10 minutes after smoking. CONCLUSIONS This study reinforces the need to investigate whether MAO-B inhibition may account for some of the behavioral and epidemiological features of smoking.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, NY 11973, USA.
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12
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Kopala LC, Tan S, Shea C, Orlik H, Vandorpe R, Honer WG. Adrenoleukodystrophy associated with psychosis. Schizophr Res 2000; 45:263-5. [PMID: 11184478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Wentzel C, Darvesh S, MacKnight C, Shea C, Rockwood K. Inter-rater reliability of the diagnosis of vascular cognitive impairment at a memory clinic. Neuroepidemiology 2000; 19:186-93. [PMID: 10859497 DOI: 10.1159/000026254] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Consensus criteria for the diagnosis of vascular dementia (VaD) are gradually being replaced with data-based criteria. We report the inter-rater reliability of a new set of empirically-derived criteria for vascular cognitive impairment (VCI). Stratified sampling, with optimal allocation, was employed to randomly select 36 patients from the Queen Elizabeth II Health Science Centre's Memory Disability Clinic. Chart reviews were conducted independently by 4 physicians. Each physician classified the patients as having either: no cognitive impairment, VCI or Alzheimer's disease (AD). VCI was further classified both clinically (VCI without dementia, VaD or AD with a vascular component) and radiographically (infarcts, white matter changes, single strategic stroke). The intraclass correlation coefficient (ICC) for the diagnosis by physicians of VCI or otherwise was based on a repeated-measures analysis of variance with raters as the independent variable. A significant coefficient of reliability (average ICC = 0.88, 95% CI = 0.80-0.93) was obtained (H(o): rho </= 0.80, p = 0.03). Where differences in diagnosis occurred, the discrepancies most commonly resulted within the subtypes of VCI (9 cases) or between the diagnoses of AD and VCI (9 cases). Instances of diagnostic incongruity were typically due to the disagreement of a single rater (10 cases). This study demonstrates a high degree of reliability of criteria for VCI by physicians in a memory clinic, and can also be understood as an aspect of construct validation of those criteria. In the absence of a readily available biological marker for VCI, clinical criteria are necessary and can be reliably employed.
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Affiliation(s)
- C Wentzel
- Division of Geriatric Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
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Black K, Shea C, Dursun S, Kutcher S. Selective serotonin reuptake inhibitor discontinuation syndrome: proposed diagnostic criteria. J Psychiatry Neurosci 2000; 25:255-61. [PMID: 10863885 PMCID: PMC1407715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
OBJECTIVE To establish specific criteria by which selective serotonin reuptake inhibitor (SSRI) discontinuation syndrome may be identified. DATA SOURCES MEDLINE and PSYCHLIT databases were searched for case reports published from 1986 to 1997 inclusive, and references of relevant articles were also searched. STUDY SELECTION Forty-six case reports of symptoms following the discontinuation of fluoxetine, fluvoxamine, paroxetine or sertraline were selected. Three studies of SSRI discontinuation were also reviewed. DATA EXTRACTION Demographic and treatment information, as well as the timing, duration, number, nature and frequency of dicontinuation symptoms. DATA SYNTHESIS Paroxetine was most frequently implicated. The drug had been tapered in half of the cases. In some cases, symptom onset began during taper, whereas, in most cases, symptoms began within 1 to 3 days of drug discontinuation. Fifty-three different symptoms were reported, with dizziness being the most common. Other common symptoms were nausea or emesis, fatigue, headache, gait instability and insomnia. Shock-like sensations, paresthesia and visual disturbances were the most rare. Without intervention, symptoms persisted for more than a week in half of the cases. In cases in which the SSRI was restarted, symptoms resolved within 72 hours. In some cases, withdrawal symptoms recurred when the same SSRI was again discontinued. CONCLUSIONS Findings were used to construct diagnostic criteria for the SSRI discontinuation syndrome. These criteria are 2 or more of the following symptoms developing within 1 to 7 days of discontinuation or reduction in dosage of an SSRI after at least 1 month's use, when these symptoms cause clinically significant distress or impairment and are not due to a general medical condition or recurrence of a mental disorder: dizziness, light-headedness, vertigo or feeling faint; shock-like sensations or paresthesia; anxiety; diarrhea; fatigue; gait instability; headache; insomnia; irritability; nausea or emesis; tremor; and visual disturbances.
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Affiliation(s)
- K Black
- Department of Psychiatry, Dalhousie University, Halifax, NS
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Dobak JD, Willems J, Howard R, Shea C, Townsend DE. Endometrial cryoablation with ultrasound visualization in women undergoing hysterectomy. J Am Assoc Gynecol Laparosc 2000; 7:89-93. [PMID: 10648745 DOI: 10.1016/s1074-3804(00)80015-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
STUDY OBJECTIVES To evaluate tissue effects of cryosurgical endometrial ablation in women just before hysterectomy, characterize ultrasound monitoring of freezing, determine the feasibility of a new probe-angling procedure, and assess the safety profile by monitoring serosal surface temperatures. DESIGN Single arm safety study enrolling ten women at two centers (Canadian Task Force classification II-2). SETTING Two clinical sites. Patients. Ten women scheduled for hysterectomy. INTERVENTION Hysterectomy with a new cryosurgical device (First Option, CryoGen, Inc., San Diego, CA) that achieves surface temperatures below -90 inverted exclamation mark C to freeze endometrium. MEASUREMENTS AND MAIN RESULTS The freeze protocol involved angling the probe toward each cornu. Maximum ice front diameter at the end of the first angled freeze ranged from 24 to 34 mm, and maximum ice ball diameter at the end of the second freeze ranged from 28 to 37 mm. The margin between the advancing ice front and serosal surface was monitored by ultrasound. In all cases the margin was safe and no reduction in serosal surface temperatures occurred. Depth of necrosis ranged from 9 to 12 mm as determined by tetrazolium staining and electron microscopy, and there was no full-thickness myometrial destruction. Total endometrial destruction was achieved. CONCLUSION Cryosurgical ablation of the endometrium with the First Option system with angled freezes and ultrasound monitoring appears to be feasible and safe given our preliminary data.
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Affiliation(s)
- J D Dobak
- CryoGen Inc., San Diego, California, USA
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Fowler JS, Wang GJ, Volkow ND, Logan J, Franceschi D, Franceschi M, MacGregor R, Shea C, Garza V, Liu N, Ding YS. Evidence that gingko biloba extract does not inhibit MAO A and B in living human brain. Life Sci 2000; 66:PL141-6. [PMID: 10698362 DOI: 10.1016/s0024-3205(99)00660-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Extracts of Ginkgo biloba have been reported to reversibly inhibit both monoamine oxidase (MAO) A and B in rat brain in vitro leading to speculation that MAO inhibition may contribute to some of its central nervous system effects. Here we have used positron emission tomography (PET) to measure the effects of Ginkgo biloba on human brain MAO A and B in 10 subjects treated for 1 month with 120 mg/day of the Ginkgo biloba extract EGb 761, using [11C]clorgyline and [11C]L-deprenyl-D2 to measure MAO A and B respectively. A three-compartment model was used to calculate the plasma to brain transfer constant K1 which is related to blood flow, and lambdak3, a model term which is a function of the concentration of catalytically active MAO molecules. Ginkgo biloba administration did not produce significant changes in brain MAO A or MAO B suggesting that mechanisms other than MAO inhibition need to be considered as mediating some of its CNS effects.
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Affiliation(s)
- J S Fowler
- Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973-5000, USA.
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Heppard M, Coddington C, Duleba A, Indman P, Isaacson K, Love B, Shoupe D, Soderstrom R, Townsend D, Walsh B, Willems J, Shea C, Dobak J. Preliminary data from multi-center study using cryogen fist option™ uterine cryoblation therapy™ in women with AUB. Int J Gynaecol Obstet 2000. [DOI: 10.1016/s0020-7292(00)85229-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Logan J, Fowler JS, Volkow ND, Wang GJ, MacGregor RR, Shea C. Reproducibility of repeated measures of deuterium substituted [11C]L-deprenyl ([11C]L-deprenyl-D2) binding in the human brain. Nucl Med Biol 2000; 27:43-9. [PMID: 10755644 DOI: 10.1016/s0969-8051(99)00088-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The purpose of this study was to assess the reproducibility of repeated positron emission tomography (PET) measures of brain monoamine oxidase B (MAO B) using deuterium-substituted [11C]L-deprenyl ([11C]L-deprenyl-D2) in normal subjects and to validate the method used for estimating the kinetic constants from the irreversible 3-compartment model applied to the tracer binding. Five normal healthy subjects (age range 23-73 years) each received two PET scans with [11C]L-deprenyl-D2. The time interval between scans was 7-27 days. Time-activity data from eight regions of interest and an arterial plasma input function was used to calculate lambda k3, a model term proportional to MAO B, and K1, the plasma to brain transfer constant that is related to blood flow. Linear (LIN) and nonlinear least-squares (NLLSQ) estimation methods were used to calculate the optimum model constants. A comparison of time-activity curves for scan 1 and scan 2 showed that the percent of change for peak uptake varied from -18.5 to 15.0% and that increases and decreases in uptake on scan 2 were associated with increases and decreases in the value of the arterial input of the tracer. Calculation of lambda k3 showed a difference between scan 1 and scan 2 in the global value ranging between -6.97 and 4.5% (average -2.1 +/- 4.7%). The average percent change for eight brain regions for the five subjects was -2.84 +/- 7.07%. Values of lambda k3 for scan 1 and scan 2 were highly correlated (r2 = 0.98; p < 0.0001; slope 0.955). Similarly, values of K1 showed a significant correlation between scan 1 and scan 2 (r2 = 0.61; p < 0.0001; slope 0.638) though the values for scan 2 were generally lower than those of scan 1. There was essentially no difference between the values of model constants calculated using the NLLSQ or LIN methods. Regional brain uptake of [11C]L-deprenyl-D2 varied between scan 1 and scan 2, driven by the differences in arterial tracer input. Application of a 3-compartment model to regional time-activity data and arterial input function yielded lambda k3 values for scan 1 and scan 2 with an average difference of -2.84 +/- 7.07%. Linear regression applied to values of lambda k3 from the LIN and NLLSQ methods validated the use of the linear method for calculating lambda k3.
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Affiliation(s)
- J Logan
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
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Fowler JS, Wang GJ, Volkow ND, Franceschi D, Logan J, Pappas N, Shea C, MacGregor RR, Garza V. Smoking a single cigarette does not produce a measurable reduction in brain MAO B in non-smokers. Nicotine Tob Res 1999; 1:325-9. [PMID: 11072429 DOI: 10.1080/14622299050011451] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Positron emission tomography (PET) studies with [11C]L-deprenyl-D2 have shown that brain monoamine oxidase (MAO) B is 40% lower in smokers than in non-smokers. Here we investigated whether MAO B inhibition can be detected after smoking a single cigarette. Eight normal healthy non-smokers (35 +/- 11 years) received two PET studies 2 h apart with [11C]L-deprenyl-D2, one at baseline and the second 5-10 min after the subject had smoked a single cigarette. Plasma nicotine and expired carbon monoxide (CO) were measured prior to smoking and 10 min after smoking completion as an index of tobacco smoke exposure. A three-compartment model was used to calculate lambda k3, a model term which is proportional to MAO B activity and which is derived from the time course of carbon-11 in the brain and the time course of the radiotracer in the plasma and K1, the plasma-to-brain transfer constant (for [11C]L-deprenyl-D2) which is related to brain blood flow. Subjects experienced difficulty inhaling and became dizzy and/or nauseous after smoking. Plasma nicotine averaged 11.6 +/- 5.5 ng/ml and expired CO averaged 8 +/- 10 ppm after smoking. The average lambda k3 and K1 for 11 different brain regions did not differ significantly between baseline and smoking. These results indicate that the reduction in MAO B in smokers probably occurs gradually and requires chronic tobacco smoke exposure.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, NY 11973, USA.
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20
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Abstract
Dementia with Lewy bodies (DLB) is common. Symptomatic treatment can be difficult. We reviewed nine consecutive patients with DLB (mean age 77.5 [range 67 to 84] years; seven men and two women; mean duration of disease 3.7 [range 1.5 to 8.0] years) who had been treated with donepezil. Each initially received 2.5 to 5 mg per day of donepezil, and was stabilized on 5 mg per day. Donepezil was increased to 10 mg per day in five patients. The mean observation period was 12 (range 8 to 24) weeks. Target symptoms included cognition, hallucinations, parkinsonism, and functional abilities. By both cognitive testing and family reports, cognition improved in seven of nine patients, remained the same in one of nine, and fluctuated in one of nine (mean Mini-Mental State Examination change 4.4 +/- 6.3 points). Function was improved or maintained in six of nine patients and fluctuated in two of nine. Hallucinations initially worsened, then fluctuated in one patient, but improvement in frequency, duration, and content was reported in eight of nine cases. In three of nine patients, treatment with donepezil resulted in worsening of parkinsonism, which in each case responded to levodopa/carbidopa. Treatment of DLB patients with donepezil for 12 weeks most commonly improved hallucinations, and sometimes improved cognition and overall function. Treatment with donepezil was sometimes associated with worse parkinsonism.
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Affiliation(s)
- C Shea
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia Canada
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Fowler JS, Volkow ND, Logan J, Pappas N, King P, MacGregor R, Shea C, Garza V, Gatley SJ. An acute dose of nicotine does not inhibit MAO B in baboon brain in vivo. Life Sci 1998; 63:PL19-23. [PMID: 9674950 DOI: 10.1016/s0024-3205(98)00251-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Tobacco smoke exposure has been shown to inhibit brain and platelet MAO B in animals and in humans. Though the mechanism(s) responsible for MAO B inhibition are not known, studies in rodents have shown that nicotine administration does not inhibit brain MAO B. In this study we investigated whether brain MAO B is also unaffected by nicotine in the living primate. Brain MAO B was measured with positron emission tomography (PET) and deuterium substituted [11C]L-deprenyl ([11C]L-deprenyl-D2) in three baboons at baseline and 5 minutes after the injection of (-)-nicotine (0.3 mg administered intravenously). A three-compartment model was used to calculate the plasma to brain transfer constant K1 which is related to blood flow, and lambda k3, which is a function of the concentration of catalytically active MAO B molecules. Nicotine administration did not produce significant changes in either of these parameters. This study in living baboons confirms previous studies in rodents and solidifies the notion that other mechanisms for MAO B inhibition observed in smokers need to be considered.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, NY 11973-5000, USA
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA
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23
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Ferreira RC, Shea C, Johnson DW, Bateman JB. Electroretinography in incontinentia pigmenti. J AAPOS 1997; 1:172-4. [PMID: 10532780 DOI: 10.1016/s1091-8531(97)90060-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- R C Ferreira
- Department of Ophthalmology, Federal University of São Paulo, Brazil
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Fowler JS, Volkow ND, Wang GJ, Logan J, Pappas N, Shea C, MacGregor R. Age-related increases in brain monoamine oxidase B in living healthy human subjects. Neurobiol Aging 1997; 18:431-5. [PMID: 9330975 DOI: 10.1016/s0197-4580(97)00037-7] [Citation(s) in RCA: 180] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Several studies of human brain postmortem report that monoamine oxidase B (MAO B) increases with age and it has been proposed that this increase reflects age-associated increases in glial cells. We measured brain MAO B in a group of normal healthy human subjects (n = 21; age range 23-86; 9 females and 12 males; nonsmokers) using [11C]L-deprenyl-D2 and positron emission tomography. Brain glucose metabolism was also measured with 18FDG in 15 of the subjects. MAO B increased (p < 0.004) in all brain regions examined except the cingulate gyrus. In contrast, subjects showed the expected regional age-related decreases in blood flow and metabolism. In the 15 subjects in whom both MAO B and LCMRglu was measured, there was a trend (p < 0.03) toward an inverse association between brain glucose metabolism and MAO B activity in the frontal and parietal cortices. Although the age-related increase in brain MAO B in living subjects is consistent with postmortem reports, the degree of increase is generally lower.
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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Abstract
OBJECTIVES To provide a brief overview of intravesical dimethly sulfoxide (DMSO) therapy for interstitial cystitis and offer a practical approach to patient treatment. METHODS A review of the literature and a summation of the experience with treatment of > 300 patients with DMSO at the Interstitial Cystitis Clinic, New England Medical Center. RESULTS DMSO is helpful in a significant number of patients and it has acceptable morbidity and an excellent safety profile. CONCLUSIONS Intravesical DMSO (singly or in combination) is one of the mainstays in the pharmacologic treatment of interstitial cystitis.
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Affiliation(s)
- J Parkin
- Interstitial Cystitis Clinic, New England Medical Center, Boston, MA 02111, USA
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26
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Tan S, Shea C, Kopala L. Paranoid schizophrenia with delusions regarding the Internet. J Psychiatry Neurosci 1997; 22:143. [PMID: 9074309 PMCID: PMC1188843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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Volkow ND, Wang GJ, Fowler JS, Logan J, Hitzemann R, Ding YS, Pappas N, Shea C, Piscani K. Decreases in dopamine receptors but not in dopamine transporters in alcoholics. Alcohol Clin Exp Res 1996; 20:1594-8. [PMID: 8986209 DOI: 10.1111/j.1530-0277.1996.tb05936.x] [Citation(s) in RCA: 349] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
It has been hypothesized that ethanol's actions on the dopamine (DA) system may participate in addiction. The purpose of this study was to evaluate the DA system in the brain of alcoholics. We evaluated 10 alcoholics and 17 nonalcoholics using positron emission tomography and [11C]raclopride to measure DA D2 receptors. In addition, in 5 of the alcoholics and 16 of the nonalcoholics, we also measured DA transporters with [11C]d-threo methylphenidate. The ratio of the distribution volumes in striatum to that in cerebellum, which corresponds to Bmax/Kd + 1, was used as model parameter of DA D2 receptor and transporter availability. Dopamine D2 receptor availability (Bmax/Kd) was significantly lower in alcoholics (2.1 +/- 0.5) than in nonalcoholics (2.7 +/- 0.6) (p < 0.05) and was not correlated with days since last alcohol use. Alcoholics showed DA transporter values similar to those in nonalcoholics. The ratio of DA D2 receptor to transporter availability was significantly higher in nonalcoholics (1.4 +/- 0.1) than in alcoholics (1.1 +/- 0.1) (p < 0.005). Alcoholics showed significant reductions in D2 receptors (postsynaptic marker) but not in DA transporter availability (presynaptic marker) when compared with nonalcoholics. Because D2 receptors in striatum are mainly localized in gamma-aminobutyric acid (GABA) cells these results provide evidence of GABAergic involvement in the dopaminergic abnormalities seen in alcoholics.
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Affiliation(s)
- N D Volkow
- Medical Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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Fowler JS, Volkow ND, Wang GJ, Pappas N, Logan J, Shea C, Alexoff D, MacGregor RR, Schlyer DJ, Zezulkova I, Wolf AP. Brain monoamine oxidase A inhibition in cigarette smokers. Proc Natl Acad Sci U S A 1996; 93:14065-9. [PMID: 8943061 PMCID: PMC19495 DOI: 10.1073/pnas.93.24.14065] [Citation(s) in RCA: 325] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Several studies have documented a strong association between smoking and depression. Because cigarette smoke has been reported to inhibit monoamine oxidase (MAO) A in vitro and in animals and because MAO A inhibitors are effective antidepressants, we tested the hypothesis that MAO A would be reduced in the brain of cigarette smokers. We compared brain MAO A in 15 nonsmokers and 16 current smokers with [11C]clorgyline and positron emission tomography (PET). Four of the nonsmokers were also treated with the antidepressant MAO inhibitor drug, tranylcypromine (10 mg/day for 3 days) after the baseline PET scan and then rescanned to assess the sensitivity of [11C]clorgyline binding to MAO inhibition. MAO A levels were quantified by using the model term lambda k3 which is a function of brain MAO A concentration. Smokers had significantly lower brain MAO A than nonsmokers in all brain regions examined (average reduction, 28%). The mean lambda k3 values for the whole brain were 0.18 +/- 0.04 and 0.13 +/- 0.03 ccbrain (mlplasma)-1 min-1 for nonsmokers and smokers, respectively; P < 0.0003). Tranyl-cypromine treatment reduced lambda k3 by an average of 58% for the different brain regions. Our results show that tobacco smoke exposure is associated with a marked reduction in brain MAO A, and this reduction is about half of that produced by a brief treatment with tranylcypromine. This suggests that MAO A inhibition needs to be considered as a potential contributing variable in the high rate of smoking in depression and in the development of more effective strategies for smoking cessation.
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973-5000, USA.
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Fowler JS, Volkow ND, Wang GJ, Pappas N, Logan J, MacGregor R, Alexoff D, Shea C, Schlyer D, Wolf AP, Warner D, Zezulkova I, Cilento R. Inhibition of monoamine oxidase B in the brains of smokers. Nature 1996; 379:733-6. [PMID: 8602220 DOI: 10.1038/379733a0] [Citation(s) in RCA: 422] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The massive health problem associated with cigarette smoking is exacerbated by the addictive properties of tobacco smoke and the limited success of current approaches to cessation of smoking. Yet little is known about the neuropharmacological actions of cigarette smoke that contribute to smoking behaviour, or why smoking is so prevalent in psychiatric disorders and is associated with a decreased risk of Parkinson's disease. Here we report that brains of living smokers show a 40% decrease in the level of monoamine oxidase B (MAO B; EC 1.4.3.4) relative to non-smokers or former smokers. MAO B is involved in the breakdown of dopamine, a neurotransmitter implicated in reinforcing and motivating behaviours as well as movement. MAO B inhibition is therefore associated with enhanced activity of dopamine, as well as with decreased production of hydrogen peroxide, a source of reactive oxygen species. We propose that reduction of MAO B activity may synergize with nicotine to produce the diverse behavioural and epidemiological effects of smoking.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, New York 11973, USA
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30
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Abstract
The binding of [18F]haloperidol to dopamine D2 and to sigma recognition sites in baboon brain was examined using positron emission tomography (PET). Studies were performed at baseline and after treatment with either haloperidol (to evaluate saturability), (+)-butaclamol (which has specificity for dopamine D2 receptors) or (-)-butaclamol (which has specificity for sigma sites). Binding was widespread. Treatment with (-)-butaclamol had no effect, whereas (+)-butaclamol selectively reduced the uptake in striatum. Haloperidol increased the clearance rate from all brain regions. These results indicate that the binding profile of [18F]haloperidol does not permit the selective examination of either dopamine D2 or sigma sites using PET.
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Affiliation(s)
- K A Yousef
- Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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31
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Abstract
A commercial laboratory robot system (Zymate PyTechnology II Laboratory Automation System) was interfaced to standard and custom laboratory equipment and programmed to perform rapid radiochemical assays necessary for plasma input function determination in quantitative PET studies in humans and baboons. A Zymark XP robot arm was used to carry out two assays: (1) the determination of total plasma radioactivity concentrations in a series of small-volume whole blood samples and (2) the determination of unchanged (parent) radiotracer in plasma using only solid phase extraction methods. Steady state robotic throughput for determination of total plasma radioactivity in whole blood samples (0.350 mL) is 14.3 samples/h, which includes automated centrifugation, pipetting, weighing and radioactivity counting. Robotic throughput for the assay of parent radiotracer in plasma is 4-6 samples/h depending on the radiotracer. Percents of total radioactivities present as parent radiotracers at 60 min, postinjection of 25 +/- 5.0 (N = 25), 26 +/- 6.8 (N = 68), 13 +/- 4.4 (N = 30), 32 +/- 7.2 (N = 18), 16 +/- 4.9 (N = 20), were obtained for carbon-11 labeled benztropine, raclopride, methylphenidate, SR 46349B (trans, 4-[(3Z)3-(2-dimethylamino-ethyl) oxyimino-3 (2-fluorophenyl)propen-1-yl]phenol), and cocaine respectively in baboon plasma and 84 +/- 6.4 (N = 9), 18 +/- 11 (N = 10), 74 +/- 5.7 (N = 118) and 16 +/- 3.7 (N = 18) for carbon-11 labeled benztropine, deprenyl, raclopride, and methylphenidate respectively in human plasma. The automated system has been used for more than 4 years for all plasma analyses for 7 different C-11 labeled compounds used routinely in our laboratory. The robotic radiotracer assay runs unattended and includes automated cleanup procedures that eliminates all human contact with plasma-contaminated containers.
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Affiliation(s)
- D L Alexoff
- Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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Ding YS, Fowler JS, Gatley SJ, Logan J, Volkow ND, Shea C. Mechanistic positron emission tomography studies of 6-[18F]fluorodopamine in living baboon heart: selective imaging and control of radiotracer metabolism using the deuterium isotope effect. J Neurochem 1995; 65:682-90. [PMID: 7616224 DOI: 10.1046/j.1471-4159.1995.65020682.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Mechanistic positron emission tomography (PET) studies using the deuterium isotope effect and specific pharmacological intervention were undertaken to examine the behavior of 6-[18F]fluorodopamine (6-[18F]-FDA; 1) and (-)-6-[18F]fluoronorepinephrine [(-)-6-[18F]FNE; 2] in the baboon heart. Two regiospecifically deuterated derivatives of 6-[18F]FDA [alpha,alpha-D2 (3) and beta,beta-D2 (4)] were used to assess the contributions of monoamine oxidase (MAO) and dopamine beta-hydroxylase, respectively, to the clearance kinetics of 6-[18F]FDA. Compound 3 showed a reduced rate of clearance, consistent with MAO-catalyzed cleavage of the alpha C-D bond, whereas compound 4 showed no change, indicating that cleavage of the beta C-D bond is not a rate-limiting step. Pretreatment with pargyline, an MAO inhibitor, also decreased the rate of clearance. Desipramine and tomoxetine [norepinephrine (NE) uptake inhibitors], but not GBR-12909 (a dopamine uptake inhibitor), blocked the uptake of both (-)-6-[18F]FNE and 6-[18F]FDA, with (-)-6-[18F]FNE showing a higher degree of blockade. Chiral HPLC demonstrated that 6-[18F]FDA is stereoselectively converted to (-)-6-[18F]FNE in vivo in the rat heart. These studies demonstrate that (a) the more rapid clearance of 6-[18F]FDA relative to (-)-6-[18F]FNE can be largely accounted for by metabolism by MAO; (b) selective deuterium substitution can be used to protect a radiotracer from metabolism in vivo and to favor a particular pathway; (c) 6-[18F]FDA and (-)-6-[18F]FNE share the NE transporter; (d) 6-[18F]FDA is stereoselectively converted to (-)-6-[18F]FNE in vivo; and (e) the profile of radioactivity in the heart for 6-[18F]FDA is complex, probably including labeled metabolites as well as neuronal and nonneuronal uptake.
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Affiliation(s)
- Y S Ding
- Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973, USA
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Abstract
BACKGROUND Currently one federal program funds community health centers (CHCs) to provide services in underserved communities, and a second supports development of primary care teaching programs. Teaching CHCs respond to both program's goals, but their development is hindered by restrictive regulations of the two programs and lack of information regarding cost. METHOD Spreadsheet software was used to develop a model that allocates cost components of a CHC-based residency. Productivity and staffing data from a teaching CHC program were used to estimate the cost of training and its sensitivity to selected variables. Data from 1992 through 1994 were collected from the family practice residency sponsored by the Brown University School of Medicine, the Memorial Hospital of Rhode Island, and the Blackstone Valley Community Health Center. RESULTS An educational supplement of $13.21 per visit would be required for the program to be cost-neutral relative to staff. The cost of outpatient training for a resident averaged $13,935 per year. Residents would "break even" if they saw patients at 19% above the average rate recommended by the residency review committee. If staff physicians instead of residents had provided the patient care, the CHC would have saved $6,171 per resident. Additional savings from improved physician recruiting and decreased turnover would increase the value of the program to the CHC. Cost was most sensitive to resident productivity, precepting arrangements, nursing staff support, and staff turnover. CONCLUSION Developing graduate medical education programs in CHCs can be a cost-effective way of increasing the pool of appropriately trained primary care physicians and increasing health care access for underserved populations. If teaching CHCs are to expand, provisions will need to be made for adequate reimbursement of their costs.
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Affiliation(s)
- T F Jones
- Department of Family Medicine, Brown University School of Medicine, Providence, Rhode Island, USA
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Fowler JS, Volkow ND, Logan J, Wang GJ, MacGregor RR, Schyler D, Wolf AP, Pappas N, Alexoff D, Shea C. Slow recovery of human brain MAO B after L-deprenyl (Selegeline) withdrawal. Synapse 1994; 18:86-93. [PMID: 7839316 DOI: 10.1002/syn.890180203] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
L-Deprenyl (Selegeline) is an enzyme-activated irreversible inhibitor of monoamine oxidase B (MAO B; EC 1.4.3.4). It is used to treat Parkinson's disease at a dose of 5 mg twice a day. Since enzyme inhibition is irreversible, the recovery of functional enzyme activity after withdrawal from L-deprenyl requires the synthesis of new enzyme. We have measured a 40 day half-time for brain MAO B synthesis in Parkinson's disease and in normal subjects after withdrawal from L-deprenyl. This is the first measurement of the synthesis rate of a specific protein in the living human brain. L-Deprenyl is currently used by 50,000 patients with Parkinson's disease in the United States and its use is expected to increase with reports that it may be beneficial in Alzheimer's disease. The slow turnover of brain MAO B suggests that the current clinical dose of L-deprenyl may be excessive and that the clinical efficacy of reduced dosing should be evaluated. Such an evaluation may have mechanistic importance as well as an impact on reducing the side effects and the costs arising from excessive drug use.
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973
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Fowler JS, Ding YS, Volkow ND, Martin T, MacGregor RR, Dewey S, King P, Pappas N, Alexoff D, Shea C. PET studies of cocaine inhibition of myocardial norepinephrine uptake. Synapse 1994; 16:312-7. [PMID: 8059340 DOI: 10.1002/syn.890160407] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Positron emission tomography (PET), [11C]cocaine, and (-)-6-[18F]fluoronorepinephrine [(-)-6-[18F]NE] were used to determine the extent to which the binding of labeled cocaine in the baboon heart represents binding to the norepinephrine transporter and to characterize the functional consequences of cocaine administration on the norepinephrine transporter. Peak heart binding of [11C]cocaine was high (0.038-0.055%/g) and clearance was rapid (t1/2 from peak: 2.5-9 min) for both tracer doses and a pharmacological dose. The binding of a tracer dose of labeled cocaine could not be inhibited by desipramine, tomoxetine, cocaine, nomifensine, or benztropine. The behavior of a pharmacological dose of [11C]cocaine could not be distinguished from a tracer dose and also could not be inhibited by tomoxetine. However, pretreatment with cocaine profoundly inhibited norepinephrine uptake as assessed by (-)-6-[18F]NE. Recovery was slow with only 48% of the baseline (-)-6-[18F]NE uptake being recovered by 78 minutes after cocaine administration. [11C]Benzoylecgonine, a vasoactive metabolite of cocaine, showed negligible retention in heart. The results of this study (i.e., the rapid clearance of cocaine from the heart, the inability to inhibit cocaine binding with desipramine and tomoxetine, and its relatively long-lasting effects on norepinephrine uptake) reinforce the need to understand the link between cocaine pharmacokinetics and norepinephrine transporter function and its relationship to cardiotoxicity.
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Affiliation(s)
- J S Fowler
- Brookhaven National Laboratory, Upton, New York 11973
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Fowler JS, Volkow ND, Logan J, Schlyer DJ, MacGregor RR, Wang GJ, Wolf AP, Pappas N, Alexoff D, Shea C. Monoamine oxidase B (MAO B) inhibitor therapy in Parkinson's disease: the degree and reversibility of human brain MAO B inhibition by Ro 19 6327. Neurology 1993; 43:1984-92. [PMID: 8413955 DOI: 10.1212/wnl.43.10.1984] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The possibility of slowing the progression of Parkinson's disease (PD) with inhibitors of monoamine oxidase B (MAO B) has stimulated the development of new MAO B inhibitor drugs. Ro 19 6327 is a highly selective inhibitor of MAO B currently under clinical investigation. We used positron emission tomography (PET) and the MAO B tracer [11C]L-deprenyl to determine the degree and reversibility of human brain MAO B inhibition by Ro 19 6327 in six early Parkinson's disease patients who were treated with different doses of Ro 19 6327 (25 mg [n = 3], 50 mg [n = 2], and 100 mg [n = 1]; 0.34 to 1.4 mg/kg) every 12 hours for 1 week. Each patient had three PET scans to assess baseline MAO B activity, degree of trough inhibition, and reversibility. A control group of four elderly normal subjects was scanned twice to assess reproducibility of repeated measures. Four of the patients showed reduction of MAO B concentration to 1% to 7% of baseline on doses of 0.43 mg/kg or greater, and the remaining two at 0.34 mg/kg showed significant but incomplete inhibition (10% to 21% of baseline in the global region and in the thalamus, basal ganglia, and mesencephalon). Thus, 0.4 mg/kg or greater of Ro 19 6327 given every 12 hours is the minimum dose necessary to provide > 90% inhibition of brain MAO B in patients with early PD. Brain MAO B activity returned to baseline values by 36 hours after drug discontinuation.
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973
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Jack B, Culpepper L, Anandarajah G, Shea C. The teaching community health center. R I Med 1993; 76:299-302. [PMID: 8329779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Volkow ND, Fowler JS, Wang GJ, Dewey SL, Schlyer D, MacGregor R, Logan J, Alexoff D, Shea C, Hitzemann R. Reproducibility of repeated measures of carbon-11-raclopride binding in the human brain. J Nucl Med 1993; 34:609-13. [PMID: 8455077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Carbon-11-raclopride has been successfully utilized with PET to assess changes in endogenous dopamine concentration after pharmacological intervention in the living baboon brain. For similar studies to be done in humans, measurements of 11C-raclopride with no intervention need to be reproducible. In order to test the reproducibility (test-retest) of 11C-raclopride binding in the human brain, we performed repeated studies on two different days. Studies were done in five normal controls with no pharmacological intervention. Time-activity (%dose/cc) curves for 11C-raclopride in the basal ganglia (BG) and cerebellum (CBL) were highly reproducible with an average difference in peak uptake for repeated studies in the same individual of 4%. The BG to CBL ratio for the average activity concentration between 30 and 60 min showed differences that ranged from -7% to 8% between the repeated studies. Graphical analysis to obtain the distribution volume revealed intrasubject values that ranged from -9% to 7% for the ratio of the distribution volume in BG to that in CBL. These studies demonstrate that in order to use 11C-raclopride to measure an individual's change in relative dopamine concentration secondary to pharmacological or behavioral intervention, a change in striatal 11C-raclopride binding in excess of 10% is required.
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Affiliation(s)
- N D Volkow
- Medical and Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973
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Ding YS, Fowler JS, Dewey SL, Wolf AP, Logan J, Gatley SJ, Volkow ND, Shea C, Taylor DP. Synthesis and PET studies of fluorine-18-BMY 14802: a potential antipsychotic drug. J Nucl Med 1993; 34:246-54. [PMID: 8094094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
BMY 14802 is a compound containing fluorine developed as a potential antipsychotic drug. It has a moderate affinity for the sigma binding site and a very low affinity for dopamine D2 receptors and has been predicted to have antipsychotic properties without the side effect potential of existing drugs. To assess the brain uptake, pharmacokinetics, stereoselectivity and binding properties of this potential antipsychotic drug, enantiomerically pure samples of (-) and (+)-[18F]BMY 14802 were examined in a baboon with PET. A tissue distribution with racemic labeled BMY 14802 was also carried out in mice. Radiochemical yields of 15% at the end of bombardment (EOB) for the racemic mixture, and 5% for each enantiomer with a specific activity of 2-5 Ci/mumol at EOB were obtained. In baboons, [18F]BMY 14802 cleared rapidly from the plasma and the glucuronidated [18F]BMY 14802 appeared. Radioactivity peaked (0.04-0.07% dose/cc) in all areas of the brain examined at about 5 min postinjection. It then rapidly cleared to about 30% of peak value by 20 min postinjection and to less than 10% of peak by 60 min postinjection in all regions. A similar rapid clearance from brain was also observed in mice. Pretreatment with unlabeled BMY 14802 (7 mg/kg), did not produce the expected reductions in distribution volume and clearance halftimes consistent with receptor binding. Although the rapid kinetics of [18F]BMY 14802 made it difficult to resolve the processes of transport and binding of the labeled drug, the lack of regional distribution consistent with the known distribution of sigma binding sites as well as the lack of stereoselectivity suggest that the behavior of BMY 14802 in the brain is dominated by its transport properties in tissue rather than its binding to sigma sites. Moreover, its rapid clearance from brain may be a limiting factor in its use as an antipsychotic drug.
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Affiliation(s)
- Y S Ding
- Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973
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Alexoff DL, Casati R, Fowler JS, Wolf AP, Shea C, Schlyer DJ, Shiue CY. Ion chromatographic analysis of high specific activity 18FDG preparations and detection of the chemical impurity 2-deoxy-2-chloro-D-glucose. Int J Rad Appl Instrum A 1992; 43:1313-22. [PMID: 1333458 DOI: 10.1016/0883-2889(92)90002-v] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Because of the widespread use of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) prepared by the "Julich" method or its variants it was decided necessary to determine the major chemical impurities present in the final product. An analytical system for quantifying FDG was developed using pulsed amperometry after separation by high-performance anion exchange chromatography. With this system a heretofore unidentified impurity, 2-deoxy-2-chloro-D-glucose (C1DG, ca 20-2000 micrograms; typically < 100 micrograms), was found in our preparation and in those from other laboratories using the "Julich" method. C1DG arises from Cl- ion displacement during the labeling procedure where Cl- ion comes from several sources, and Cl- ion displacement from the HCl used in the hydrolysis step. FDG mass was present in the same preparations at a level of ca 1-40 micrograms. Other major chemical constituents were glucose (ca 1-6 mg) and mannose (ca 10-18 micrograms). Glycerol, arising from sterilizing filters, was also detected in most preparations. Although C1DG is a chemical impurity which has not been detected previously in nca FDG preparations, its biochemical and pharmacological properties are similar to FDG and 2-deoxy-D-glucose. Thus it is unlikely that the presence of small quantities of C1DG found in typical FDG preparations (ca 100 micrograms) would have adverse pharmacological or toxicological consequences that would limit continued application of this radiopharmaceutical in basic and clinical studies.
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Affiliation(s)
- D L Alexoff
- Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973
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Abstract
Surface-associated motility has been observed in the Deleya marina type strain ATCC 25374 (strain 219). Slime tracks and a complex growth pattern, characteristic of gliding motility, developed on semisolid marine-agar motility plates. Cell movement observed by light microscopy consisted of rapid glides and flips by single cells and groups of cells. Following the development of the gliding cell growth pattern, a subpopulation of swimming cells appeared. The variation in motility was random and reversible in subculture. Electron microscopic comparisons of cells of the two motility types showed that gliding cells had no obvious motility organelles, whereas swimming cells had polar flagella. Variable expression of gliding and swimming motility was also observed in D. marina strain 140 (ATCC 27129) and in two other species of the Deleya genus. Key words: gliding, morphological variation, Deleya, biofouling.
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Shea C, Nunley JW, Williamson JC, Smith-Somerville HE. Comparison of the adhesion properties of Deleya marina and the exopolysaccharide-defective mutant strain DMR. Appl Environ Microbiol 1991; 57:3107-13. [PMID: 1781675 PMCID: PMC183934 DOI: 10.1128/aem.57.11.3107-3113.1991] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Deleya marina 219 (ATCC 25374) produces large quantities of an acidic exopolysaccharide and characteristically forms mucoid colonies and large aggregates of cells. The exopolysaccharide of wild-type D. marina cells appears to occur as both film and fibrils in electron micrographs. The organization of exopolymeric material was indicative of structural heterogeneity. A spontaneous rough-colony mutant defective in exopolysaccharide, D. marina DMR, has been isolated. The absence of exopolymer corresponds to a nonmucoid, nonaggregating, adhesion-altered phenotype. In microplate adhesion assays, wild-type cells grown at 19 or 25 degrees C attached to hydrophilic surfaces but not to a hydrophobic surface. In contrast, mutant cells exhibited a significantly reduced level of attachment to hydrophilic surfaces and increased adhesion to a hydrophobic surface.
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Affiliation(s)
- C Shea
- Department of Biological Sciences, University of Alabama, Tuscaloosa 35487
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Eisenberg N, Fabes RA, Schaller M, Miller P, Carlo G, Poulin R, Shea C, Shell R. Personality and socialization correlates of vicarious emotional responding. J Pers Soc Psychol 1991; 61:459-70. [PMID: 1941517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The relations of personality and family characteristics to adults' negative vicarious emotional responses to sympathy and distress films were examined. Ss reported more sympathy and less personal distress and exhibited less skin conductance as well as heart rate deceleration when viewing a sympathy-evoking film. Dispositional emotional intensity and fantasy empathy were associated with greater self-reported emotional responding and higher skin conductance. Dispositional perspective taking and personal distress were positively and negatively correlated, respectively, with reported vicarious responding to the sympathy film when Ss were administered instructions to imagine the emotions of those in the films. Family cohesiveness was associated with reported sympathy and sadness in reaction to the sympathy film, whereas the expression of negative subordinate and positive emotional states in the home of origin was associated with women's reported responsivity.
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Affiliation(s)
- N Eisenberg
- Department of Psychology, Arizona State University, Tempe 85287
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Shea C, Williamson JC. A fluorometric microtiter assay for the rapid enumeration of adherent bacteria. Biotechniques 1991; 10:177. [PMID: 1711870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- C Shea
- Department of Microbiology, University of Alabama Tuscaloosa 35487
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Gatley SJ, Shea C. Radiochemical and chemical quality-assurance methods for [13N]-ammonia made from a small volume H2(16)O target. Int J Rad Appl Instrum A 1991; 42:793-6. [PMID: 1657830 DOI: 10.1016/0883-2889(91)90213-k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
HPLC and TLC systems were sought for routine assurance of [13N]NH3 for human PET studies. An ion chromatograph with conductivity and radioactivity detection was used to confirm that [13N]NO2- and [13N]NO3- were the major 13N species formed by the 16O(p, alpha)13N reaction in a small volume (0.5 mL) water target irradiated with protons (24 MeV), and that Devarda's alloy reduction and distillation in an apparatus constructed of disposable components and requiring no external heating gave radiochemically and radionuclidically pure [13N]NH3. Merck polyethylene-backed TLC plates were developed in the upper phase of the solvent mixture: H2O/acetone/propionic acid (6:4:2, v/v) saturated with NaCl. The Rf of [13N]NH3 was 0.6. HPLC was conducted with a 25 X 0.46 cm column with 2 mL/min CH3CN/10 mM aqueous sodium 1-octanesulfonate (1:2, v/v). [13N]NH3 eluted at 3.5 min.
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Affiliation(s)
- S J Gatley
- Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973
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Chung HM, Shea C, Fields S, Taub RN, Van der Ploeg LH, Tse DB. Architectural organization in the interphase nucleus of the protozoan Trypanosoma brucei: location of telomeres and mini-chromosomes. EMBO J 1990; 9:2611-9. [PMID: 2369903 PMCID: PMC552294 DOI: 10.1002/j.1460-2075.1990.tb07443.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We studied the spatial organization of chromatin in the interphase G1, S and G2 nucleus of the protozoan Trypanosoma brucei, applying in situ hybridization with conventional fluorescence and confocal scanning optical microscopy. The majority of the trypanosome telomere GGGTTA repeats from different chromosomes were found clustered together, either extending in a network through the nuclear interior or localized at the nuclear periphery. The population of one hundred mini-chromosomes was often asymmetrically located: either clustered in a narrow band in close association with the nuclear envelope or distributed into several clusters that segregated into roughly one half of the nucleus. The nuclear organization may undergo modifications during the cell cycle and development. We conclude that non-random spatial positioning of DNA exists in the nucleus of this protozoan. Finding a high level of structural organization in the interphase nucleus of T.brucei is an important first step towards understanding chromosome structure and functioning and its role in the control of gene expression.
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Affiliation(s)
- H M Chung
- Department of Genetics and Development, College of Physicians and Surgeons, Columbia University, New York, NY 10032
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Shea C, Williamson JC. Rapid analysis of bacterial adhesion in a microplate assay. Biotechniques 1990; 8:610-1. [PMID: 1694083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- C Shea
- Department of Microbiology, University of Alabama, Tuscaloosa 35487-0334
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Shiue CY, Fowler J, Wolf A, Shea C, Adam M. Improvements in the production of [18F]N-methylspiroperidol and [18F]haloperidol. J Labelled Comp Radiopharm 1989. [DOI: 10.1002/jlcr.25802601165] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
The structure and transcriptional regulation of the 1.8 variant cell surface glycoprotein (VSG) gene expression site located on a 430-kilobase (kb) chromosome was examined in a 430-kb-chromosome-specific library. Using 32P-labeled nascent transcripts generated by nuclear run-on, we selected recombinant clones derived from the 430-kb chromosome which were coordinately activated with the 1.8 VSG gene. The results show that a repetitive region with a minimum size of 27 kb is coordinately activated with the 1.8 VSG gene. As with the 1.8 VSG gene, transcription is by RNA polymerases that are insensitive to the drug alpha-amanitin at concentrations up to 1 mg/ml. Transcription results in the generation of several stable variant-specific mRNAs. These mRNAs most likely belong to a family of repetitive expression-site-associated genes.
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Affiliation(s)
- C Shea
- Department of Genetics and Development, Columbia University, New York, New York 10032
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50
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Abstract
To understand the control of differential variant cell surface glycoprotein (VSG) gene expression in T. brucei, we studied VSG gene and expression site transcription regulation. We show that the interchromosomal duplicative transposition of VSG gene 118, on an unusually large transposed segment, results in the transcriptional activation of a cotransposed RNA polymerase I-like (pol I) promoter, from which the VSG gene is transcribed. Transcription of VSG genes by pol I can therefore be regulated by DNA rearrangements that affect positional control of gene expression. A 5' cap is added in trans to the pol I-derived pre-mRNA, by addition of a pol II-derived 35 nucleotide mini-exon. A second gene (ESAG1) is located 25 kb upstream of the VSG 118 gene and is also transcribed. This expression site therefore contains at least two independently regulated genes. We discuss the putative importance of a nucleolar location for VSG gene and expression site transcription regulation.
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