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1.
Sci Rep ; 10(1): 1161, 2020 01 24.
Article in English | MEDLINE | ID: mdl-31980681

ABSTRACT

Plumage colouration in birds is important for a plethora of reasons, ranging from camouflage, sexual signalling, and species recognition. The genes underlying colour variation have been vital in understanding how genes can affect a phenotype. Multiple genes have been identified that affect plumage variation, but research has principally focused on major-effect genes (such as those causing albinism, barring, and the like), rather than the smaller effect modifier loci that more subtly influence colour. By utilising a domestic × wild advanced intercross with a combination of classical QTL mapping of red colouration as a quantitative trait and a targeted genetical genomics approach, we have identified five separate candidate genes (CREBBP, WDR24, ARL8A, PHLDA3, LAD1) that putatively influence quantitative variation in red-brown colouration in chickens. By treating colour as a quantitative rather than qualitative trait, we have identified both QTL and genes of small effect. Such small effect loci are potentially far more prevalent in wild populations, and can therefore potentially be highly relevant to colour evolution.


Subject(s)
CREB-Binding Protein/genetics , Chickens/genetics , Feathers/chemistry , Pigmentation/genetics , Quantitative Trait Loci , WD40 Repeats/genetics , Animals , CREB-Binding Protein/physiology , Chickens/metabolism , Chromosome Mapping , Crosses, Genetic , Female , Genetic Association Studies , Lod Score , Male , Wings, Animal
2.
Patient Educ Couns ; 102(8): 1528-1534, 2019 08.
Article in English | MEDLINE | ID: mdl-30928343

ABSTRACT

OBJECTIVE: The objective of this study was to explore research participants' (adults, age 50-65) perceptions of receiving cardiovascular risk information. METHODS: Five focus group interviews (N = 31) were performed with research participants aged 50-65 who participated in the Swedish CArdioPulmonary BioImage Study (SCAPIS). The interviews were analyzed using qualitative content analysis. RESULTS: The categories; the complexity of cardiovascular risk; insufficient presentation of test result; emotional responses; and health examinations provides confirmation, emerged. The test results were written in medical terms and lacked recommendations for further action which made it difficult for lay people to understand and use, and for some, also caused unnecessary worry. CONCLUSION: There was inadequate guidance concerning the implications of the test results, especially for participants without clinical findings. In order to allow research participants to obtain better cognitive and behavioral control, improvements are needed with regard to how personal risk information is communicated in research projects connected to health services. PRACTICAL IMPLICATIONS: The participants largely relied on physical signs when assessing their own cardiovascular risk. Health examinations are crucial for helping to add nuance to individuals' risk perceptions. For personal health information to have any real value for individuals, it must be designed from a user perspective.


Subject(s)
Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/psychology , Patient Education as Topic , Patients/psychology , Aged , Emotions , Empowerment , Female , Focus Groups , Humans , Male , Middle Aged , Prospective Studies , Qualitative Research , Risk Factors , Sweden
3.
J Community Genet ; 7(3): 203-14, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27225888

ABSTRACT

Reproductive autonomy, medicalization, and discrimination against disabled and parental responsibility are the main ongoing ethical debates concerning reproductive genetic screening. To examine Swedish healthcare professionals' views on preconception expanded carrier screening (ECS), a qualitative study involving academic and clinical institutions in Sweden was conducted in September 2014 to February 2015. Eleven healthcare professionals including clinicians, geneticists, a midwife, and a genetic counselor were interviewed in depth using a semi-structured interview guide. The questionnaire was constructed after reviewing the main literature and meetings with relevant healthcare providers. The interviews were recorded, transcribed verbatim, and content analyzed for categories and subcategories. Participants nurtured many ethical and non-ethical concerns regarding preconception ECS. Among the ethical concerns were the potential for discrimination, medicalization, concerns with prioritization of healthcare resources, and effects on reproductive freedom. The effects of implementation of preconception ECS, its stakeholders, regulations, and motivation are some of non-ethical concerns. These concerns, if not addressed, may affect the uptake and usage of carrier screening within Swedish healthcare system. As this is a qualitative study with a small non-random sample size, the findings cannot be generalized. The participants had little to no working experience with expanded screening panels. Moreover, the interviews were conducted in English, a second language for the participants, which might have limited the expression of their views. However, the authors claim that the findings may be pertinent to similar settings in other Scandinavian countries.

4.
Int J Tuberc Lung Dis ; 19(2): 244-50, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25574926

ABSTRACT

BACKGROUND: The exacerbation of asthma by workplace conditions is common, but little is known about which agents pose a risk. OBJECTIVE: We used data from an existing survey of adults with asthma to identify occupational exposures associated with severe exacerbation of asthma. DESIGN: Questionnaires were completed by 557 working adults with asthma. Severe exacerbation of asthma in the past 12 months was defined as asthma-related hospitalization, or reports of both unplanned asthma care and treatment with a short course of oral corticosteroids. Occupational exposures for the same time period were assessed using an asthma-specific job exposure matrix. We modeled severe exacerbation to yield prevalence ratios (PRs) for exposures while controlling for potential confounders. RESULTS: A total of 164 participants (29%) were positive for severe exacerbation, and 227 (40.8%) were assessed as being exposed to asthma agents at work. Elevated PRs were observed for several specific agents, notably the irritant subcategories of environmental tobacco smoke (PR 1.84, 95%CI 1.34-2.51) among all participants, inorganic dusts (PR 2.53, 95%CI 1.37-4.67) among men, and the low molecular weight subcategory of other highly reactive agents (PR 1.97, 95%CI 1.08-3.60) among women. CONCLUSION: Among working adults with asthma, severe exacerbation was associated with several occupational agents.


Subject(s)
Asthma/epidemiology , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Tobacco Smoke Pollution/adverse effects , Adolescent , Adult , Asthma/etiology , Asthma/physiopathology , Female , Humans , Male , Occupational Diseases/etiology , Occupational Diseases/physiopathology , Prevalence , Severity of Illness Index , Surveys and Questionnaires , Young Adult
5.
Acta Neurol Scand ; 132(2): 97-104, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25630925

ABSTRACT

BACKGROUND: Excessive daytime sleepiness (EDS) is common in Parkinson's disease (PD), but its role and relation to other PD features is less well understood. OBJECTIVE: To investigate potential predictors of EDS in PD and to explore how EDS relates to other motor and non-motor PD features. METHODS: 118 consecutive persons with PD (54% men; mean age, 64) were assessed regarding EDS using the Epworth Sleepiness Scale (ESS) and a range of motor and non-motor symptoms. Variables significantly associated with ESS scores in bivariate analyses were used in multiple regression analyses with ESS scores as the dependent variable. Principal component analysis (PCA) was conducted to explore the interrelationships between ESS scores and other motor and non-motor PD aspects. RESULTS: Among 114 persons with complete ESS data, significant independent associations were found between ESS scores and axial/postural/gait impairment, depressive symptoms, and pain (R2, 0.199). ESS scores did not load significantly together with any other PD features in the PCA. CONCLUSIONS: Only a limited proportion of the variation in EDS could be accounted for by other symptoms, and EDS did not cluster together with any other PD features in PCAs. This suggests that EDS is a separate manifestation differing from, for example, poor sleep quality and fatigue.


Subject(s)
Disorders of Excessive Somnolence/etiology , Parkinson Disease/complications , Aged , Female , Humans , Male , Middle Aged , Regression Analysis
6.
Mol Ecol ; 23(9): 2275-86, 2014 May.
Article in English | MEDLINE | ID: mdl-24655072

ABSTRACT

Sexual selection and the ornaments that inform such choices have been extensively studied, particularly from a phenotypic perspective. Although more is being revealed about the genetic architecture of sexual ornaments, much still remains to be discovered. The comb of the chicken is one of the most widely recognized sexual ornaments, which has been shown to be correlated with both fecundity and bone allocation. In this study, we use a combination of multiple intercrosses between White Leghorn populations and wild-derived Red Junglefowl to, first, map quantitative trait loci (QTL) for bone allocation and, second, to identify expression QTL that correlate and colocalize with comb mass. These candidate quantitative genes were then assessed for potential pleiotropic effects on bone tissue and fecundity traits. We identify genes that correlate with both relative comb mass and bone traits suggesting a combination of both pleiotropy and linkage mediates gene regulatory variation in these traits.


Subject(s)
Bone and Bones/anatomy & histology , Chickens/anatomy & histology , Chickens/genetics , Comb and Wattles/anatomy & histology , Genetic Linkage , Genetic Pleiotropy , Quantitative Trait Loci , Animals , Chromosome Mapping , Crosses, Genetic , Female , Fertility/genetics , Male , Phenotype
7.
Mar Pollut Bull ; 64(7): 1375-85, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22658577

ABSTRACT

In recent years, the shipping of environmentally hazardous cargo has increased considerably in the Baltic proper. In this study, a large number of hypothetical oil spills with an idealized, passive tracer are simulated. From the tracer distributions, statistical measures are calculated to optimize the quantity of tracer from a spill that would stay at sea as long as possible. Increased time may permit action to be taken against the spill before the oil reaches environmentally vulnerable coastal zones. The statistical measures are used to calculate maritime routes with maximum probability that an oil spill will stay at sea as long as possible. Under these assumptions, ships should follow routes that are located south of Bornholm instead of the northern routes in use currently. Our results suggest that the location of the optimal maritime routes depends on the season, although interannual variability is too large to identify statistically significant changes.


Subject(s)
Environmental Monitoring/methods , Models, Chemical , Petroleum Pollution/statistics & numerical data , Ships/methods , Water Pollution, Chemical/statistics & numerical data , Oceans and Seas , Petroleum/analysis , Seawater/chemistry , Ships/statistics & numerical data , Water Movements , Water Pollutants, Chemical/analysis
8.
Cartilage ; 2(4): 384-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-26069596

ABSTRACT

OBJECTIVE: The aim of the present study was to investigate the intra-articular duration of Durolane™ in a rabbit model to allow comparison between Durolane™ residence time and data reported for other hyaluronic acid products as well as native hyaluronic acid. DESIGN: (14)C-labeled Durolane™ was manufactured by labeling the cross-linker used for stabilization. A single injection of approximately 0.3 mL (14)C-labeled Durolane™ was administered intra-articularly in both knee joints of male New Zealand White rabbits. At days 1, 2, 3, 7, 28, 60, 96, and 120 after injection, the knee joints of 4 animals were collected, and the radioactivity of the remaining gel was measured. The obtained data were fitted by exponential models to calculate the half-life of the gel. Two additional rabbits were used for histology of the joint 127 days after the injection. RESULTS: The elimination of (14)C-labeled Durolane™ followed first-order kinetics with an apparent half-life of approximately 32 days. Histology showed no morphological changes in the knee joints. CONCLUSIONS: This study shows that Durolane™ has a half-life of 32 days in the rabbit knee joint, which is much longer compared to literature data on hyaluronic acid and other modified hyaluronic acid products.

9.
Int J STD AIDS ; 21(8): 558-62, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20975088

ABSTRACT

The aim of this study was to evaluate the effect of an educational intervention concerning human papillomavirus (HPV) directed at Swedish first year high school students. The intervention consisted of a class room lesson, a website and a folder. Outcome variables were knowledge of HPV and attitudes to preventive methods such as HPV vaccination, condom use and Pap smear testing. An intervention group (n = 92) was matched with two comparison groups (n = 184). At baseline, the median score for HPV knowledge was one out of 10 in both groups. At follow-up, the median knowledge score had increased to six in the intervention group, but was still one in the comparison group (P < 0.001). Attitudes to HPV vaccination, condom use and Pap smear testing remained the same (P > 0.05). In conclusion, a short school-based intervention can greatly increase the students' knowledge about HPV, but attitudes and behaviours are less easy to influence.


Subject(s)
Health Education/methods , Health Knowledge, Attitudes, Practice , Papillomaviridae/pathogenicity , Papillomavirus Infections/prevention & control , Schools , Students , Uterine Neoplasms/prevention & control , Adolescent , Condoms , Female , Humans , Internet , Male , Papanicolaou Test , Papillomaviridae/immunology , Papillomavirus Infections/epidemiology , Papillomavirus Infections/virology , Papillomavirus Vaccines , Program Evaluation , Sweden , Uterine Neoplasms/epidemiology , Uterine Neoplasms/virology , Vaginal Smears
10.
Eur Respir J ; 36(4): 743-50, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20351033

ABSTRACT

The goal of this study was to identify occupational risk factors for severe exacerbation of asthma and estimate the extent to which occupation contributes to these events. The 966 participants were working adults with current asthma who participated in the follow-up phase of the European Community Respiratory Health Survey. Severe exacerbation of asthma was defined as self-reported unplanned care for asthma in the past 12 months. Occupations held in the same period were combined with a general population job-exposure matrix to assess occupational exposures. 74 participants reported having had at least one severe exacerbation event, for a 1-yr cumulative incidence of 7.7%. From regression models that controlled for confounders, the relative risk (RR) was statistically significant for low (RR 1.7, 95% CI 1.1-2.6) and high (RR 3.6, 95% CI 2.2-5.8) biological dust exposure, high mineral dust exposure (RR 1.8, 95% CI 1.02-3.2), and high gas and fumes exposure (RR 2.5, 95% CI 1.2-5.5). The summary category of high dust, gas, or fumes exposure had RR 3.1 (95% CI 1.9-5.1). Based on this RR, the population attributable risk was 14.7% among workers with current asthma. These results suggest occupation contributes to approximately one in seven cases of severe exacerbation of asthma in a working population, and various agents play a role.


Subject(s)
Asthma/etiology , Adult , Asthma/diagnosis , Disease Progression , Female , Humans , Male , Middle Aged , Models, Statistical , Occupational Diseases/therapy , Occupational Exposure/adverse effects , Occupational Health , Risk , Risk Factors , Surveys and Questionnaires
11.
Health Care Anal ; 18(3): 239-51, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19779975

ABSTRACT

In spite of the growing interest in nursing ethics, few studies have focused on ethical dilemmas experienced by nurses working with clinical studies as 'research nurses'. The aim of the present study was to describe and explore ethical dilemmas that Swedish research nurses experience in their day-to-day work. In a qualitative study a purposeful sample of six research nurses from five wards of differing disciplines in four Swedish hospitals was interviewed. The analysis displayed several examples of ethical dilemmas, primarily tensions between the nurses' obligations to the study and to the patients involved. A guiding moral principle for the nurses was patient-centeredness, where the interest of research must not override the interest of the patient. In situations where tensions between research and patient interests occurred, and doctors and nurses disagreed upon the judgement, the nurses sometimes chose to follow the doctors' advice, and thus acted against their own moral judgment. Such situations seemed to create feelings of moral distress among the nurses. They described their profession as being 'invisible' and as lacking opportunities for ethical competence building. The conclusion is that research nurses frequently experience severe and difficult ethical dilemmas in their daily work. They need to be acknowledged as a particular profession in the health care organisation and encouraged to develop their specific ethical competence.


Subject(s)
Decision Making/ethics , Ethics, Nursing , Nursing Methodology Research/ethics , Adult , Clinical Competence , Humans , Middle Aged , Morals , Nurse-Patient Relations/ethics , Nursing Staff, Hospital/ethics , Nursing Staff, Hospital/psychology , Physician-Nurse Relations , Qualitative Research , Sweden
12.
Int J STD AIDS ; 20(2): 102-7, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19182055

ABSTRACT

The aim of the study was to investigate knowledge of and attitudes to sexually transmitted infection (STI) and STI prevention with special focus on human papillomavirus (HPV) and the new vaccine against HPV, among 16-year-old high school students in a Swedish context. A study-specific questionnaire was distributed to 572 first year high school students from five different high schools in a medium-sized town in Sweden. The students lacked knowledge of HPV and its association with cervical cancer. Similarly, their knowledge of the new vaccine was limited. Their attitude to condom use when having sex with a new partner was positive, but decreased if oral contraceptives were used and if they were vaccinated against an STI. The main source of information was the school, followed by youth clinics and the media. The results highlight the clinical importance for school nurses and personnel at youth clinics to inform adolescents about HPV and its association with cancer.


Subject(s)
Health Knowledge, Attitudes, Practice , Papillomavirus Infections , Papillomavirus Vaccines/administration & dosage , Sexually Transmitted Diseases , Students , Uterine Cervical Neoplasms , Vaccination/psychology , Adolescent , Adolescent Behavior , Adult , Condoms/statistics & numerical data , Cross-Sectional Studies , Female , Humans , Male , Papillomaviridae , Papillomavirus Infections/prevention & control , Papillomavirus Infections/transmission , Papillomavirus Infections/virology , Sexually Transmitted Diseases/etiology , Sexually Transmitted Diseases/prevention & control , Sexually Transmitted Diseases/transmission , Surveys and Questionnaires , Sweden , Uterine Cervical Neoplasms/prevention & control , Uterine Cervical Neoplasms/virology , Vaccination/statistics & numerical data , Young Adult
13.
Phys Rev Lett ; 100(10): 105501, 2008 Mar 14.
Article in English | MEDLINE | ID: mdl-18352201

ABSTRACT

We have theoretically studied the possibility to control the equilibrium solubility of dopants in semiconductor alloys, by strategic tuning of the alloy concentration. From the modeled cases of C(0) in Si(x)Ge(1-x), Zn(-) and Cd(-) in Ga(x)In(1-x)P it is seen that under certain conditions the dopant solubility can be orders of magnitude higher in an alloy or multilayer than in either of the elements of the alloy. This is found to be due to the solubility's strong dependence on the lattice constant for size mismatched dopants. The equilibrium doping concentration in alloys or multilayers could therefore be increased significantly. More specifically, Zn- in a Ga(x)In(1-x)P multilayer is found to have a maximum solubility for x = 0.9, which is 5 orders of magnitude larger than that of pure InP.

14.
Neuroimage ; 32(3): 1134-41, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16857389

ABSTRACT

Active efflux transporters in the blood-brain barrier lower the brain concentrations of many drug molecules and endogenous substances and thus affect their central action. The objective of this investigation was to study the dynamics of the entire inhibition process of the efflux transporter P-glycoprotein (P-gp), using positron emission tomography (PET). The P-gp marker [(11)C]verapamil was administered to anesthetized rats as an i.v. bolus dose followed by graded infusions via a computerized pump system to obtain a steady-state concentration of [(11)C]verapamil in brain. The P-gp modulator cyclosporin A (CsA) (3, 10 and 25 mg/kg) was administered as a short bolus injection 30 min after the start of the [(11)C]verapamil infusion. The CsA pharmacokinetics was studied in whole blood in a parallel group of rats. The CsA blood concentrations were used as input to model P-gp inhibition. The inhibition of P-gp was observed as a rapid increase in brain concentrations of [(11)C]verapamil, with a maximum after 5, 7.5 and 17.5 min for the respective doses. The respective increases in maximal [(11)C]verapamil concentrations were 1.5, 2.5 and 4 times the baseline concentration. A model in which CsA inhibited P-gp by decreasing the transport of [(11)C]verapamil out from the brain resulted in the best fit. Our data suggest that it is not the CsA concentration in blood, but rather the CsA concentration in an effect compartment, probably the endothelial cells of the blood-brain barrier that is responsible for the inhibition of P-gp.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors , Blood-Brain Barrier/drug effects , Brain/diagnostic imaging , Cyclosporine/pharmacology , Immunosuppressive Agents/pharmacology , Algorithms , Animals , Biotransformation , Calcium Channel Blockers/administration & dosage , Calcium Channel Blockers/pharmacokinetics , Carbon Radioisotopes , Cyclosporine/blood , Immunosuppressive Agents/blood , Isotope Labeling , Male , Models, Statistical , Positron-Emission Tomography , Rats , Rats, Sprague-Dawley , Verapamil/administration & dosage , Verapamil/pharmacokinetics
15.
Eur J Pharmacol ; 534(1-3): 122-8, 2006 Mar 18.
Article in English | MEDLINE | ID: mdl-16612840

ABSTRACT

The general anaesthetic ketamine affects the central cholinergic system in several manners, but its effect on spinal acetylcholine release, which may be an important transmitter in spinal antinociception, is unknown. This study aimed to investigate the effect of ketamine on spinal acetylcholine release. Microdialysis probes were placed intraspinally in male rats, and acetylcholine was quantified with HPLC. Anaesthesia was switched from isoflurane (1.3%) to ketamine (150 mg/kg h), which resulted in a 500% increased acetylcholine release. The increase was attenuated during nicotinic receptor blockade (50 microM mecamylamine). The nicotinic receptor agonist epibatidine (175 microM) produced a ten-fold higher relative increase of acetylcholine release during isoflurane anaesthesia compared to ketamine anaesthesia (270% to 27%). Intraspinal administration of ketamine and norketamine both increased the acetylcholine release in high concentrations (100 microM to 10 mM). The results indicate that spinal nicotinic receptors are important for the ketamine-induced acetylcholine release, and that the effect is partly mediated at the spinal level.


Subject(s)
Acetylcholine/metabolism , Anesthetics, Dissociative/pharmacology , Ketamine/analogs & derivatives , Mecamylamine/pharmacology , Receptors, Nicotinic/drug effects , Spinal Cord/drug effects , Anesthetics, Inhalation/pharmacology , Animals , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Isoflurane/pharmacology , Ketamine/pharmacology , Male , Nicotinic Agonists/pharmacology , Nicotinic Antagonists/pharmacology , Pyridines/pharmacology , Rats , Rats, Sprague-Dawley , Spinal Cord/metabolism , Time Factors
16.
Thorax ; 61(3): 221-5, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16396946

ABSTRACT

BACKGROUND: An association between indoor dampness and respiratory symptoms has been reported, but dampness as a risk factor for the onset or remission of respiratory symptoms and asthma is not well documented. METHOD: This follow up study included 16 190 subjects from Iceland, Norway, Sweden, Denmark, and Estonia who had participated in the European Community Respiratory Health Survey (ECRHS I). Eight years later the same subjects answered a postal questionnaire that included questions on respiratory symptoms and indicators of indoor dampness. RESULTS: Subjects living in damp housing (18%) had a significantly (p<0.001) higher prevalence of wheeze (19.1% v 26.0%), nocturnal breathlessness (4.4% v 8.4%), nocturnal cough (27.2% v 36.5%), productive cough (16.6% v 22.3%) and asthma (6.0% v 7.7%). These associations remained significant after adjusting for possible confounders. Indoor dampness was a risk factor for onset of respiratory symptoms but not for asthma onset in the longitudinal analysis (OR 1.13, 95% CI 0.92 to 1.40). Remission of nocturnal symptoms was less common in damp homes (OR 0.84, 95% CI 0.73 to 0.97). CONCLUSIONS: Subjects living in damp housing had a higher prevalence of respiratory symptoms and asthma. Onset of respiratory symptoms was more common and remission of nocturnal respiratory symptoms was less common in subjects living in damp housing.


Subject(s)
Housing/standards , Respiration Disorders/epidemiology , Adult , Asthma/epidemiology , Europe/epidemiology , Female , Housing/statistics & numerical data , Humans , Incidence , Longitudinal Studies , Male , Odds Ratio , Prevalence , Risk Factors
17.
Eur J Pharmacol ; 525(1-3): 69-73, 2005 Nov 21.
Article in English | MEDLINE | ID: mdl-16297380

ABSTRACT

It has been shown that analgesics such as morphine, lidocaine and clonidine increase the release of spinal acetylcholine. Acetylcholine may therefore play an important role in the regulation of spinal pain threshold. Since behavioral as well as in vitro studies have shown a clear involvement of GABA (gamma-amino butyric acid) receptors in the regulation of spinal nociceptive mechanisms, the present study focused on the role of GABA receptors for spinal acetylcholine release control. GABA receptor agonists and antagonists were infused via a spinal microdialysis probe and acetylcholine release was measured. The GABA(A) receptor agonist muscimol decreased acetylcholine release and the antagonist bicuculline increased acetylcholine release. The GABA(B) receptor agonist baclofen decreased acetylcholine release whereas the antagonist saclofen did not change acetylcholine release. The results suggest that both GABA receptor subtypes have an inhibitory role on spinal dorsal horn acetylcholine release and that the GABA(A) receptors are tonically regulating acetylcholine release.


Subject(s)
Acetylcholine/metabolism , Posterior Horn Cells/metabolism , Receptors, GABA-A/metabolism , Receptors, GABA-B/metabolism , Animals , Baclofen/analogs & derivatives , Baclofen/pharmacology , Bicuculline/pharmacology , GABA Agonists/pharmacology , GABA Antagonists/pharmacology , GABA-A Receptor Agonists , GABA-A Receptor Antagonists , GABA-B Receptor Agonists , GABA-B Receptor Antagonists , Male , Microdialysis , Muscimol/pharmacology , Posterior Horn Cells/drug effects , Rats , Rats, Sprague-Dawley
18.
J Nucl Med ; 46(11): 1881-8, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16269603

ABSTRACT

UNLABELLED: Detection of epidermal growth factor receptor (EGFR) overexpression in many carcinomas provides important diagnostic information, which can influence patient management. The use of PET may enable such detection in vivo by a noninvasive procedure with high sensitivity. The aim of this study was to develop a method for preparation of a positron-emitting tracer based on a natural ligand to EGFR, the recombinant human epidermal growth factor (hEGF), and to perform a preclinical evaluation of the tracer. METHODS: DOTA-hEGF (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) was prepared by coupling of a N-sulfosuccinimide ester of DOTA to hEGF. The conjugate was labeled with a generator-produced positron-emitting nuclide, (68)Ga (half-life = 68 min), using microwave heating. Binding specificity, affinity, internalization, and retention of (68)Ga-DOTA-hEGF was studied in 2 EGFR-expressing cell lines, U343 glioma cells and A431 cervical carcinoma cells. Biodistribution and microPET visualization studies were performed in BALB/c nu/nu mice bearing A431 carcinoma xenografts. RESULTS: A 1-min-long microwave-assisted labeling provided radioactivity incorporation of 77% +/- 4%. Both cell lines demonstrated receptor-specific uptake of the conjugate, rapid internalization of the tracer, and good retention of radioactivity. Binding to both cell lines occurred with high affinity, approximately 2 nmol/L. The biodistribution study demonstrated accumulation of radioactivity in xenografts and in EGFR-expressing organs. The microPET imaging study enabled visualization of tumors and demonstrated quick--within 5 min--localization of radioactivity in tumors. CONCLUSION: (68)Ga-DOTA-hEGF has potential for imaging EGFR overexpression in tumors.


Subject(s)
Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/metabolism , Epidermal Growth Factor/analogs & derivatives , ErbB Receptors/metabolism , Glioma/diagnostic imaging , Glioma/metabolism , Organometallic Compounds/pharmacokinetics , Animals , Cell Line, Tumor , Drug Evaluation, Preclinical , Epidermal Growth Factor/pharmacokinetics , Feasibility Studies , Female , Gene Expression Regulation, Neoplastic , Humans , Isotope Labeling/methods , Metabolic Clearance Rate , Mice , Mice, Inbred BALB C , Mice, Nude , Organ Specificity , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Tissue Distribution
19.
Eur J Pharmacol ; 509(2-3): 127-34, 2005 Feb 21.
Article in English | MEDLINE | ID: mdl-15733547

ABSTRACT

Stimulation of spinal serotonin (5-HT) receptors results in analgesia and release of acetylcholine. We investigated the involvement of 5-HT1, 5-HT2, and 5-HT3 receptor subtypes in the regulation of spinal acetylcholine release. A spinal microdialysis probe was placed dorsally at about the C5 level in anaesthetized rats. The selective serotonin reuptake inhibitor citalopram was found to increase acetylcholine release when infused via the microdialysis probe. Several doses of the 5-HT receptor agonists 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT, 5-HT1A), 1,4-dihydro-3-(1,2,3,6-tetrahydro-4-pyridinyl)-5H-pyrrolo[3,2-b]pyridin-5-one dihydrochloride (CP93129, 5-HT1B), alpha-methyl-5-hydroxytryptamine maleate (m5-HT, 5-HT2), 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI, 5-HT2C), and 1-(m-chlorophenyl)-biguanide (5-HT3) were subsequently infused via the microdialysis probe. Only 8-OH-DPAT, CP93129, and m5-HT increased acetylcholine release dose dependently. The 5-HT1A receptor selective antagonist (S)-N-tert-butyl-3-(4-(2-methoxyphenyl)piperazine-1-yl)-2-phenylpropanamide hydrochloride and the 5-HT2A receptor selective antagonist ketanserin tartrate inhibited the 8-OH-DPAT and the m5-HT induced acetylcholine release. The results suggest that 5-HT1A and the 5-HT2A receptors are involved in the regulation of acetylcholine release in the spinal cord.


Subject(s)
Acetylcholine/metabolism , Receptors, Serotonin/metabolism , Serotonin/analogs & derivatives , Spinal Cord/metabolism , 8-Hydroxy-2-(di-n-propylamino)tetralin/pharmacology , Amphetamines/pharmacology , Animals , Biguanides/pharmacology , Citalopram/pharmacology , Dose-Response Relationship, Drug , Ketanserin/pharmacology , Male , Microdialysis , Piperazines/pharmacology , Pyridines/pharmacology , Pyrroles/pharmacology , Rats , Rats, Sprague-Dawley , Serotonin/pharmacology , Serotonin Antagonists/pharmacology , Serotonin Receptor Agonists/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Spinal Cord/drug effects , Time Factors
20.
Nucl Med Biol ; 32(2): 129-36, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15721758

ABSTRACT

The serotonin transporter radioligand [11C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile, or [11C]DASB, was examined in order to assess its potential for measuring fluctuations in endogenous serotonin concentrations with positron emission tomography. Binding characteristics of [11C]DASB and the propensity for serotonin to displace the tracer were explored in rat brain homogenates. Experiments showed that serotonin displaced [11C]DASB in vitro. Ex vivo experiments performed after tranylcypromine injection (3 or 15 mg/kg) showed a dose-dependent trend in radioactivity uptake and suggested that serotonin may compete with [11C]DASB for transporter binding.


Subject(s)
Aniline Compounds/pharmacokinetics , Aniline Compounds/therapeutic use , Brain/diagnostic imaging , Brain/metabolism , Positron-Emission Tomography/methods , Serotonin/metabolism , Sulfides/pharmacokinetics , Sulfides/therapeutic use , Animals , Feasibility Studies , Male , Metabolic Clearance Rate , Neurotransmitter Agents/metabolism , Organ Specificity , Protein Binding , Radiopharmaceuticals/pharmacokinetics , Rats , Rats, Sprague-Dawley , Tissue Distribution
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