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T Abel

Publications and source records attributed to T Abel.

At least 19 recordsLinked to original sources
PubMed2002

Behavioral analysis of CREB alphadelta mutation on a B6/129 F1 hybrid background.

The cyclic AMP (cAMP)-response element binding protein (CREB) is an activity-dependent transcription factor that plays a role in synaptic plasticity and memory storage in Aplysia, Drosophila, and rodents. Mice with targeted deletions of two CREB isoforms (alpha and delta; CREB alphadelta mice) have been characterized on a mixed genetic background of C57BL/6 (B6) and 129/SvEv (129), as well as on a defined F1 hybrid of B6 and FVB/N, and these results suggest that the phenotype of CREB alphadelta mice depends critically on genetic background. In an examination of the hypothesis that the role of CREB in learning and memory can be influenced by strain differences, we analyzed mice with the CREB alphadelta mutation on an F1 hybrid background of B6 and 129 strains. CREB alphadelta mice on this background had impaired short-term and long-term cued and contextual fear conditioning and normal spatial learning in the Morris water maze. Our results suggest that at least some aspects of hippocampal function are normal in CREB alphadelta mice, and that CREB alphadelta mice on the B6/129 F1 background have alterations in amygdala function. These studies underscore the importance of controlling for genetic background in the behavioral analysis of knockout and transgenic mice.

Animals↗
PubMed2001

Different requirements for protein synthesis in acquisition and extinction of spatial preferences and context-evoked fear.

Many molecular accounts of long-term memory storage postulate that the synthesis of new proteins is necessary for long-term changes in neuronal function. These experiments generally have examined the learning that occurs as associations are acquired between neutral and biologically important stimuli. Little is known about the importance of protein synthesis in the establishment of memories for extinction, which occurs as the relations established during acquisition are severed. Extinction appears to be an active learning process that results in the formation of new memories rather than in the simple erasure or forgetting of memories from acquisition. Furthermore, under certain circumstances, extinction can result in long-term changes in behavior lasting for days to weeks. Here we show that although memories for the acquisition of spatial and contextual learning required protein synthesis, memories for extinction formed in the absence of protein synthesis. These results suggest that acquisition and extinction are mediated by distinct molecular mechanisms and that long-term memories can form in the absence of protein synthesis.

Animals↗
PubMed2001

The cAMP-protein kinase A signal transduction pathway modulates ethanol consumption and sedative effects of ethanol.

Ethanol and other drugs of abuse modulate cAMP-PKA signaling within the mesolimbic reward pathway. To understand the role of the cAMP-PKA signal transduction in mediating the effects of ethanol, we have studied ethanol consumption and the sedative effects of ethanol in three lines of genetically modified mice. We report that mice with the targeted disruption of one Gsalpha allele as well as mice with reduced neuronal PKA activity have decreased alcohol consumption compared with their wild-type littermates. Genetic reduction of cAMP-PKA signaling also makes mice more sensitive to the sedative effects of ethanol, although plasma ethanol concentrations are unaffected. In contrast, mice with increased adenylyl cyclase activity resulting from the transgenic expression of a constitutively active form of Gsalpha in neurons within the forebrain are less sensitive to the sedative effects of ethanol. Thus, the cAMP-PKA signal transduction pathway is critical in modulating sensitivity to the sedative effects of ethanol as well as influencing alcohol consumption.

Adenylyl Cyclases↗
PubMed2001

Receptor polymorphisms and diseases.

The aim of our review is to summarize common genetic variations of some receptors associated with clinical consequences, which were not outlined in the previous special issue of this journal. Because of the multiple pathomechanisms of diseases, a set of genetic variation can play a role in the development of pathological conditions. From the data available three articles would merit a greater interest. In systemic lupus erythematosus the associations related to some polymorphisms of Fc-, tumor necrosis factor (TNF) alpha- and interferon receptor may explore new autoimmunological and inflammatorical pathomechanisms. In the endocrinology, the androgen receptor repeat polymorphism will exert significant aspects in the development of prostate cancer. The pleoitropic responsibility of vitamin D3 receptor polymorphism in the pathogenesis of immunological disorders (primary biliary cirrhosis, inflammatory bowel disease, type 1 diabetes mellitus) and of malignancies (malignant melanoma, breast cancer) shed light on the importance of common nuclear receptors. Nevertheless, in the future studies a more consistent approach minimizing requirement bias in the selection of patients will approve our understanding the role of genetic influence on the pathogenesis of diseases.

Antigens, CD↗
PubMed2001

[Health promotion by sports and physical activity: politics, behavior and infrastructures in a European comparison].

OBJECTIVES: The focus of physical activity promotion is moving from measures to increase health-enhancing physical activity on the individual level to higher-level strategies including policy and environmental approaches. Scientific evidence, traditionally related to individual-based strategies, calls for adaptation and refinement when environmental and policy changes become more relevant. METHODS: This paper investigates differences in physical activity promotion and public policy among six European countries. Data from a European study on public health promotion policy and health behaviours (MAREPS) is analysed to study behaviour, community-based opportunities for physical activity, and populations' perception of the effectiveness of their national policies in promoting physical activity. RESULTS: Analyses show significant differences in both involvement in and perceived opportunities for physical activity among the investigated countries. Populations in Finland, Switzerland, and The Netherlands show comparably higher participation and, at the same time, perceive better opportunities for physical activity within the residential environment than people in East Germany, Belgium, and Spain. Moreover, respondents from the former group of nations report considerably greater contribution of health policy in their country to the promotion of physical activity than respondents from the latter group. CONCLUSIONS: In conclusion, the results provide empirical support for the significance of environmental and policy approaches with regard to physical activity. Opportunities created by implementing such approaches may enable populations to develop more active lifestyles conducive to health. Further research employing longitudinal designs could be especially helpful to explore the causalities of the relationship between policy, environment and physical activity.

Adolescent↗
PubMed2001

Quality of life in children and adolescents: a European public health perspective.

OBJECTIVES: The measurement of health-related quality of life (HRQOL) is increasingly important as a means of monitoring population health status over time, of detecting sub-groups within the general population with poor HRQOL, and of assessing the impact of public health interventions within a given population. At present, no standardised instrument exists which can be applied with equal relevance in pediatric populations in different European populations. The collaborative European KIDSCREEN project aims to develop a standardised screening instrument for children's quality of life which will be used in representative national and European health surveys. Participants of the project are centres from Austria, France, Germany, Netherlands, Spain, Switzerland, and United Kingdom. By including the instrument in health services research and health reporting, it also aims at identifying children at risk in terms of their subjective health, thereby allowing the possibility of early intervention. METHODS: Instrument development will be based on constructing a psychometrically sound HRQOL instrument taking into account the existing state of the art. Development will centre on literature searches, expert consultation (Delphi Methods) and focus groups with children and adolescents (8-17 years). According to international guidelines, items will be translated into the languages of the seven participating countries for a pilot test with 2,100 children and their parents in Europe. The final instrument will be used in representative mail and telephone surveys of HRQOL in 1,800 children and their parents per country (total n = 25,200) and normative data will be produced. The potential for implementing the measurement tool in health services and health reporting will also be evaluated in several different research and public health settings. The final analysis will involve national and cross cultural-analysis of the instrument. RESULTS: The international, collaborative nature of the KIDSCREEN project means it is likely to provide many challenges in terms of producing an instrument which is conceptually and linguistically appropriate for use in many different countries, but it will also provide the opportunity to develop, test and implement the first truly cross-national HRQOL instrument developed for use in children and adolescents. This will help to contribute to a better understanding of perceived health in children and adolescents and to identify populations at risk.

Adolescent↗
PubMed2001

Gender bias in the assessment of physical activity in population studies.

OBJECTIVES: Despite their generally more health promoting behaviours, women are found to participate less in physical activity than men. This study explores possible gender bias in measurement of physical activity in population studies. METHODS: Data collected by telephone (CATI) from the Berne Lifestyle Panel in 1996 is utilised. A representative samples of the population of the city of Berne comprised N = 1119 cases. Gender differences are assessed for the weekly frequency of three measurements of physical activities. RESULTS: An indicator of sport and exercise showed higher physical activity among men, while the indicator of habitual physical activity showed higher rates of daily walking and biking among women. A combined indicator of general physical activity showed no significant gender differences. CONCLUSIONS: The results provide empirical evidence on potential risk of underestimation of physical activity among women and of misclassification with respect to high or low risk behaviour patterns.

Aged↗
PubMed2001

Sleep and memory: a molecular perspective.

This review synthesizes data from behavioral studies examining the role of sleep in memory storage with what is known about the molecular mechanisms of memory consolidation. There are striking similarities in the effects on memory storage of post-training pharmacological manipulations and post-training manipulations of sleep. For example, inhibition of protein synthesis is most effective if it occurs at a time post-training when rapid eye movement (REM) sleep is required for memory consolidation. The neurochemical changes that occur across sleep/wake states, especially the cholinergic changes that occur in the hippocampus during REM sleep, might provide a mechanism by which sleep modulates specific cellular signaling pathways involved in hippocampus-dependent memory storage.

Acetylcholine↗
PubMed2001

The importance of the social environment for physically active lifestyle--results from an international study.

Physically active lifestyles are regularly associated with improved health and quality of life. Differences in lifestyles in society can partly be understood through the differences in the social and physical environment. This study examines the relationships between reported physical activity, and the extent of perceived support for physical activity in the physical and policy environment (e.g. facilities, programmes and other opportunities), and in the social environment. The data for the study come from a cross-cultural health policy study called MAREPS. In total, 3342 adults, 18 years or older, from six countries (Belgium, Finland, Germany, The Netherlands, Spain, Switzerland) were interviewed via telephone. Respondents were categorised as active or inactive according to self-reported physical activity. Social environmental factors and physical and policy environmental factors were also assessed. The analysis of the data was informed by social cognitive theory, although the study was not originally designed for this purpose. Sixty-eight percent of females and 70% of males were active. The proportions of active and inactive varied by countries to a great extent. The strongest independent predictor of being physically active was social environment. Those who perceived low social support from their personal environment (i.e. family, friends, school and workplace) were more than twice as likely to be sedentary compared to those who reported high social support from their personal environment. Specific knowledge of the programmes and actions for physical activity and sport was also a strong predictor of being active. A supportive physical and policy environment was not associated with participation in physical activity as strongly as had been anticipated. The variation between countries was stronger predictor of being active than the physical and policy environment variables. This study generates the hypotheses and raises the questions that in a preliminary way, there appears to be some relationships between aspects of physical and social environment and physical activity participation. However, future research is needed to refine and clarify this.

Adolescent↗
PubMed2001

Molecular mechanisms of memory acquisition, consolidation and retrieval.

Memory is often considered to be a process that has several stages, including acquisition, consolidation and retrieval. Memory can be modified further through reconsolidation and performance can change during extinction trials while the original memory remains intact. Recent studies of the molecular basis of these processes have found that many signaling molecules are involved in several stages of memory but, in some cases, molecular pathways may be selectively recruited only during certain stages of memory.

Animals↗
PubMed2001

Fear conditioning in inbred mouse strains: an analysis of the time course of memory.

Three mouse strains were examined for short- and long-term memory for Pavlovian fear conditioning measured 1 hr and 24 hr after conditioning. Both DBA/2J and CBA/J mice exhibit reduced long-term memory for contextual fear conditioning compared with C57BL/6J mice. In cued fear conditioning, however, DBA/2J mice show reduced short- and long-term memory compared with C57BL/6J mice, whereas CBA/J mice exhibit reductions only in short-term memory. These results underscore the importance of examining the time course of memory retention, and they suggest that inbred mouse strains may provide a diversity of phenotypes. The results also suggest that the processes of short- and long-term memory storage as well as contextual and cued fear conditioning are dissociable and are mediated by genetically distinct neurobiological mechanisms.

Animals↗
PubMed2001

Self reported physical activity, public health, and perceived environment: results from a comparative European study.

STUDY OBJECTIVE: The focus of physical activity promotion is moving from methods for increasing health enhancing physical activity on the individual level to higher level strategies including environmental and policy approaches. Scientific inquiry, traditionally related to individual-based strategies, requires adaptation and refinement when environmental and policy changes become more relevant. The objective of this study is to investigate the significance for behaviour and health of community-based environments that encourage physical activity. DESIGN AND SETTING: The article presents data and results from a cross sectional comparative survey of the general population in six European countries (Belgium, Finland, Germany (East and West), Netherlands, Spain, Switzerland). Specifically, the relation between perceived community-based opportunities for physical activity, self reported physical activity, and self rated health status is investigated. PARTICIPANTS: Representative samples of general populations (adults 18 years or older). Overall response rate: 53.5%. Sample sizes realised: Belgium: n = 389; Finland: n = 400; Germany (East): n = 913; Germany (West): n = 489; Netherlands: n = 366; Spain: n = 380; Switzerland: n =406. MAIN RESULTS: Analyses show that best opportunities are reported by people who are lightly to moderately physically active. People's self rated health is moderately, but significantly associated with both perceived opportunities, and physical activity itself. These predictors interact in that especially for women, the health impact of physical activity is more pronounced in case of good opportunities. CONCLUSIONS: The paper shows the potential of opportunities within residential and community environments with regard to physical activity, both for behaviour and health. Opportunities may enable the population, especially women, to develop an active lifestyle, and thus improve their health. Future studies with objective indicators for physical activity related environments should test the findings that are based on perceptions.

Adolescent↗
PubMed2001

Cadaveric fibula, locking plate, and allogeneic bone matrix for anterior cervical fusions after cervical discectomy for radiculopathy or myelopathy.

OBJECT: The authors have previously reported that the results of using cadaveric fibula and locking plate (CF/LP) fusion following anterior cervical discectomy (ACD) for cervical spondylotic radiculopathy and myelopathy are superior to those obtained using autologous iliac crest (AIC) grafts in the short term. The long-term results of using this construct are important in substantiating this improvement. The authors report on 246 consecutive patients (54% smokers) who underwent ACD with CF/LP fusion (175 with allogeneic bone matrix [ABM]) and compare them with 111 consecutive patients in whom AIC fusions (49% smokers) were performed by the same surgeons. METHODS: The study is a retrospective nonrandomized analysis, and chi-square statistics were used. Bone densitometric studies of AIC grafts and CF grafts were performed. A paired t-test was used for statistical analysis of the results. Disease in the group of patients undergoing CF/LP fusion included soft-disc herniation with radiculopathy in 14, soft-disc hemiation with myelopathy in seven, cervical spondylotic radiculopathy in 144, cervical spondylotic myelopathy in 75, AIC graft collapse pseudarthrosis in five, and ACD with no fusion collapse/kyphosis in one. Operations consisted of single-level CF/LP fusion in 142 patients and multilevel CF/LP fusion in 104. Perioperative complications in the CF/LP group included three cases of transient hoarseness. There were no transfusions, infections, neurological injuries, or deaths. The mean hospital length of stay was 1.2 days (28% outpatient and 66% 23-hour stay). The mean follow-up period was 60 months (range 12-94 months). Ten patients were lost to follow up after 1 year. Long-term complications included one traumatic plate fracture and one symptomatic pseudarthrosis with plate fracture. At 1 year and beyond, in 245 (99.6%) of 246 patients radiographically documented fusion with no motion at the fused level on flexion-extension films was demonstrated. There was no kyphosis, no symptomatic screw plate backout, and no CF/LP graft collapse (100% in the ABM group). In the 111 consecutive patients with AIC fusions, however, there was a 17% graft-related complication rate. There were significantly fewer graft-related complications in the CF/LP group (p < 0.001). There was no difference in neurological outcome for any of the groups. In the groups undergoing single-level ACD there was a significantly greater chance of complete relief of neck pain CF/LP fusion compared with those undergoing AIC fusion (p < 0.02). There was a significantly greater chance of AIC collapse with the passage of time compared with CF graft (p < 0.02). Time until return to work was shorter for the CF/LP group by 5 to 6 weeks (p < 0.02). There was a higher rate of radiographically documented pseudarthrosis in the AIC group (p < 0.006). The mean bone densitometry for the CF/LP group was 0.7 g/cm2, significantly greater than that of the AIC group, which was 0.2 g/cm2 (paired t-test p < 0.001). CONCLUSIONS: When fusion is necessary following ACD, the results of CF/LP fusion are significantly superior in the first 5 years after surgery compared with those for AIC fusions. It remains to be determined if demineralized ABM has a significant effect in enhancing fusion.

Adult↗
PubMed2001

An immediate-shock freezing deficit with discrete cues: a possible role for unconditioned stimulus processing mechanisms.

Five experiments with C57BL/6 mice (Mus musculus) investigated whether failures in shock processing might contribute to deficits in freezing that occur after an animal receives a shock immediately on exposure to a conditioning context. Experiment 1 found that more contextual freezing resulted from delayed shocks than from immediate shocks across 4 shock intensities. Experiment 2 extended the immediate-shock freezing deficit to discrete stimuli. Experiment 3 found that preexposure to the to-be-conditioned cue did not facilitate immediate cued conditioning. Experiment 4 found that context preexposure enhanced context-evoked fear after an immediate shock. Experiment 5 found that context preexposure also enhanced immediate cued conditioning. These findings are problematic for current theories of the immediate-shock freezing deficit that focus exclusively on processing of the conditioned stimulus, and they suggest that failures in shock processing may contribute to the deficit.

Animals↗
PubMed2000

Parallel instabilities of long-term potentiation, place cells, and learning caused by decreased protein kinase A activity.

To further elucidate the links among synaptic plasticity, hippocampal place cells, and spatial memory, place cells were recorded from wild-type mice and transgenic "R(AB)" mice with reduced forebrain protein kinase A (PKA) activity after introduction into a novel environment. Place cells in both strains were similar during the first exposure and were equally stable for recording sessions separated by 1 hr. Place cell stability in wild-type mice was unchanged for sessions separated by 24 hr but was reduced in R(AB) mice over the longer interval. This stability pattern parallels both the reduced late-phase long-term potentiation in hippocampal slices from R(AB) mice and the amnesia for context fear conditioning seen in R(AB) mice 24 but not 1 hr after training. The similar time courses of synaptic, network, and behavioral instability suggest that the genetic reduction of PKA activity is responsible for the defects at each level and support the idea that hippocampal synaptic plasticity is important in spatial memory.

Action Potentials↗
PubMed2000

Self-rated health, life satisfaction and personal characteristics of post-menopausal women under estrogen replacement therapy.

OBJECTIVES: To describe the prevalence of oestrogen replacement therapy (ERT)-use among post-menopausal women in relation with personal and socio-economic characteristics and to examine the association of ERT-use with self-rated health and selected aspects of life satisfaction. METHODS: Population survey data were derived from a cohort study of 511 Bernese women, aged 55-65 years. Data were collected by means of telephone interviews. Overall prevalence of ERT-use, and selected associations with personal and socio-economic characteristics were investigated using descriptive statistical methods and logistic regression. The relations of ERT-use with five self-reported health measures were explored using Spearman's correlation coefficients. The associations of ERT-use with six dichotomous variables on satisfaction with various aspects of life were tested with chi-square tests in cross tabulations. RESULTS: The overall prevalence of self reported ERT-use was 17.6%. ERT was more prevalent women younger than 61 years than in women in the older age group. Women with a body mass index (BMI) under 25 reported ERT-use significantly more frequently than women with higher BMI (OR=3.16, CI 1.87-5.34). ERT-use was more prevalent in women with relatively high education: OR=2.01, CI 1.18-4.00. The self-reported health measures and the satisfaction items were not significantly associated with ERT-use. CONCLUSIONS: ERT-use among post-menopausal women was found to be associated with higher educational level and lower BMI. ERT-users did not report better health or life-satisfaction.

Aged↗