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PubMed2005

[Consequences of nosographic and trans-nosological concepts of schizophrenia].

This essay starts with a brief remark about the -- necessary -- de-tours of the historical pathway to the concept of schizophrenia. The first part on nosographic approaches then describes the results of cross-sectional and longitudinal psychopathological symptom-assembling, subgrouping by factorial analyses, and the cross-cultural stability of the emerging disease concept: The human idiopathic syndrome of structural mental decline in its clinical variegation. The second part about de-nosological approaches provides an account of the clinical concepts of basic symptoms, spectrum disorders, neuropsychological deficits and their genetic family loading. Genetics of neuropsychological deficits demonstrate in detail that risk and protective factors to schizophrenia are genetically closely enmeshed. Higher familial loading of some neuropsychological deficits compared to the actual disease itself points at the dilemma that functional psychopathology deepens causal understanding and yet looses specificity for the disease syndrome. The concluding part of this essay emphasizes some sequelae of de-nosological approaches: Better tools for earlier recognition treatment and prevention; ego-distal concepts of basic dysfunctions rather than the previous ego-proximal concepts, hence better self-esteem, insight, and de-stigmatization for patients.

History, 20th Century↗
PubMed2001

Microsatellite analysis reveals a high incidence of maternal cell contamination in 46,XX products of conception consisting of villi or a combination of villi and membranous material.

OBJECTIVE: With the use of microsatellite analysis, we sought to determine the incidence of maternal cell contamination in 46,XX products of conception consisting of villi or a combination of villi and membranous material. STUDY DESIGN: Deoxyribonucleic acid from cultured fibroblasts of 46,XX products of conception specimens and a corresponding maternal blood sample were obtained from 31 women. Maternal and fetal genotypes for several highly polymorphic microsatellite markers were compared. RESULTS: Maternal cell contamination was present in 26 (89.7%) of the 29 products of conception specimens from which conclusive results were obtained. The contamination appeared to completely obscure the fetal material in 24 of these specimens. CONCLUSIONS: A significant proportion of 46,XX karyotypes from products of conception represents maternal cell contamination. When maternal cells rather than fetal cells are karyotyped, no information is gained regarding the chromosome constitution of the abortus, and genetic counseling regarding recurrence risks for future pregnancies may be inaccurate. Thus laboratories should exercise caution when reporting normal female karyotypes on products of conception and should consider using microsatellite analysis to determine whether 46,XX results are truly representative of the fetal karyotype.

Abortion, Spontaneous↗
PubMed1999

The appearance of Kant's deontology in contemporary Kantianism: concepts of patient autonomy in bioethics.

Kant's concept of autonomy and the Kantian notion of autonomy are often conflated in bioethics. However, the contemporary Kantian notion has very little at all to do with Kant's original. In order to further bioethics discourse on autonomy, I critically distinguish the contemporary Kantian notion from Kant's original concept of moral autonomy. I then evaluate the practical relevance of both concepts of autonomy for use in bioethics. I argue that it is not appropriate to appeal to either concept toward assessing which patients we ought to respect as autonomous. Finally, I sketch criteria for what I take to be a more promising concept of autonomy for patients.

Bioethics↗
PubMed2003

Opinion: the species problem, can we achieve a universal concept?

One of the so called 'species problems' is that no universal concept exists. There is a tendency among microbiologists to criticize the hitherto devised concept. It is considered by some researchers as being too conservative and not suitable to be compared with those for eukaryotes. However, such problem is not only restricted to prokaryotes, but among other taxonomies comparisons seem to be impossible. As it is argued, the underlying cause to this problem is the reductionistic and monistic use of taxonomy. Analyzing the more than 22 devised concepts it seems possible to achieve a universal species concept. However, this might not be pragmatic. For the time being, a pluralistic sense of the species concept might be accepted, and one will have to recognize that any comparison among different taxonomies will be difficult.

Bacteria↗
PubMed2001

Relationships between proenvironmental attitudes and concepts of nature.

The author investigated relationships between proenvironmental attitudes and concepts of nature. Proenvironmental attitudes were measured on a 5-point scale containing 27 items. The author developed a 5-point scale containing 20 items to assess concepts of nature. The author administered those 2 scales to 140 young adults and adolescents at 2 Japanese institutions of higher education. An investigation of 6 proenvironmental attitudes and 20 concepts of nature showed some significant relationships. Factor analysis of the 20 concepts of nature produced 2 factors: Positive Evaluation of Nature and Rejection of Manipulation of Human Life. Most relationships were significant between the scores for the 6 proenvironmental attitudes and those for the 2 factors of concepts of nature.

Adolescent↗
PubMed1999

Insemination at the second of two induced oestrous periods in anoestrous dairy cows increases conception rates to first service.

AIM: To determine whether mating previously anoestrous cows on their second, rather than first, oestrus post pm-turn could increase conception rates to that service. METHODS: Cows diagnosed as anovulatory anoestrus were allocated to two groups, starting treatment on Day -17 (OES2) or on Day -7 (OESI) where the date of the planned start of mating = Day 0. All cows were treated with intravaginal progesterone (CIDR device) for 6 days and an injection of 1 mg oestradiol benzoate 24 h after removal of the device. Cows in the OES2 group were also injected with prostaglandin F2alpha on Day 0. RESULTS: During the first 7 days of mating, 61.8% (207/335) and 88.2% (328/372) of cows in the OES2 and OESl groups, respectively, were inseminated on detection of oestrus (p <0.001). Oestrus without ovulation occurred in 1.5% of cows in the OES2 group and 6.2% of cows in the OESl group during this period (p <0.01). Of those cows inseminated in the first week of mating, conception rates were 54.0% in the OES2 group and 45.5% in the OESl group (p = 0.05). There was no significant difference in median interval from start of mating to conception between the two groups (24 and 22 days for OES2 and OESl, respectively, p >0.05). CONCLUSION: Mating previously anoestrous cows on their second, rather than first oestrus post partum increased conception rates to that service. However, median intervals from start of mating to conception were not altered.

Journal Article↗
PubMed2002

An analysis, using concept mapping, of diabetic patients' knowledge, before and after patient education.

This study was designed to assess whether concept maps used with diabetic patients could describe their cognitive structure, before and after having followed an educational programme. Ten diabetic patients, in Paris and Geneva, were interviewed and, during the interview, a concept map was drawn up by the researcher, using the patient's words. This was done on three different occasions: the first day of the educational programme (Pre-evaluation), the last day (Post 1) of a week of education, then 3 to 4 months after education (Post 2). Twenty-eight maps were analysed, using a grid that quantified and qualified the knowledge expressed (knowledge categories, concept links, exactitude) and the organization of that knowledge (hierarchization of concept, cross-links). The examples shown in the maps of the 10 patients gave an illustration of how knowledge was developed or maintained with education, and also showed some learning difficulties encountered by the patients, the changes or preservation of their beliefs and the patients' preoccupations. This study shows that concept maps can be a suitable technique to explore the type and organization of the patients' prior knowledge and to visualize what they have learned after an educational programme.

Adult↗
PubMed1995

Concept generation: validation of a test of executive functioning in a normal aging population.

A new test, Concept Generation, was designed to fractionate the processes that underlie sorting performance in an efficient paper-and-pencil format. The test was administered to 60 subjects, aged 18-79. Results indicated age-related deficits for self-initiated concept formation, shifting set, output monitoring, and perseverative tendencies. When cuing was introduced to increase structure, age group differences were attenuated or eliminated. Within the older group, subgroups were identified based upon the nature of their repetitions. The hypothesis that sorting behavior is mediated by executive functions led to correlational analyses between Concept Generation scores and other measures of executive functioning. The pattern of correlations supported the construct validity of the Concept Generation test. In addition to providing preliminary evidence for the usefulness of Concept Generation in executive functioning assessment, the results replicated and extended previous work on executive functioning in older individuals.

Adolescent↗
PubMed2005

General practitioners' conceptions of depressive disorders in relation to regional sales levels of antidepressive drugs. A study based on a postal survey and ecological data.

OBJECTIVES: To examine how local sales levels of antidepressive agents (ADs) correlated with GPs' conceptions of depressive disorders and of factors that may influence their work with depressed patients. DESIGN: A postal questionnaire survey to GPs requesting their conceptions of depression and their opinions of additional factors that may influence their work with depressed patients. GPs' conceptions and opinions were compared with local sales rates of ADs. SETTINGS: Three selected groups of Swedish municipalities: those with the highest, the average, and the lowest sales rates of ADs. SUBJECTS: All 535 GPs who worked in the selected municipalities. MAIN OUTCOME MEASURES: Spearman rank correlations for responses to the questionnaire with the sales levels of ADs. RESULTS: High sales levels correlated positively with a high evaluation of ADs' effectiveness in depression and panic disorders and were inversely correlated with the degree of appreciation of psychotherapy-based treatments. High sales levels were also associated with a high evaluation of GPs' own clinical and private experience, with a positive appreciation of the work with depressed patients and with a high level of participation in the pharmaceutical companies' activities. The demonstrated statistical correlations were not particularly strong and included less than half of the items. CONCLUSIONS: This ecological study confirms a number of statistical associations between sales levels of ADs and GPs' prevailing conceptions of factors related to depression. However, their explanatory value of the geographical sale variation appears limited. To further clarify this variation, studies employing information on individual GPs' conceptions and prescribing are required.

Adult↗
PubMed2000

The effects of a computer skill training programme adopting social comparison and self-efficacy enhancement strategies on self-concept and skill outcome in trainees with physical disabilities.

PURPOSE: The aim of this controlled, quasi-experimental study was to evaluate the effects of both self-efficacy enhancement and social comparison training strategy on computer skills learning and self-concept outcome of trainees with physical disabilities. METHOD: The self-efficacy enhancement group comprised 16 trainees, the tutorial training group comprised 15 trainees, and there were 25 subjects in the control group. Both the self-efficacy enhancement group and the tutorial training group received a 15 week computer skills training course, including generic Chinese computer operation, Chinese word processing and Chinese desktop publishing skills. The self-efficacy enhancement group received training with tutorial instructions that incorporated self-efficacy enhancement strategies and experienced self-enhancing social comparisons. The tutorial training group received behavioural learning-based tutorials only, and the control group did not receive any training. The following measurements were employed to evaluate the outcomes: the Self-Concept Questionnaire for the Physically Disabled Hong Kong Chinese (SCQPD), the computer self-efficacy rating scale and the computer performance rating scale. RESULTS: The self-efficacy enhancement group showed significantly better computer skills learning outcome, total self-concept, and social self-concept than the tutorial training group. The self-efficacy enhancement group did not show significant changes in their computer self-efficacy: however, the tutorial training group showed a significant lowering of their computer self-efficacy. CONCLUSIONS: The training strategy that incorporated self-efficacy enhancement and positive social comparison experiences maintained the computer self-efficacy of trainees with physical disabilities. This strategy was more effective in improving the learning outcome (p = 0.01) and self-concept (p = 0.05) of the trainees than the conventional tutorial-based training strategy.

Adult↗
PubMed2004

Identifying the concepts contained in outcome measures of clinical trials on stroke using the International Classification of Functioning, Disability and Health as a reference.

OBJECTIVES: To systematically identify and quantify the concepts contained in outcome measures in stroke trials using the International Classification of Functioning, Disability and Health (ICF) as a reference. METHODS: Randomized controlled trials between 1992 and 2001 were located in MEDLINE and selected according to predefined criteria. Outcome measures were extracted and concepts contained in the outcome measures were linked to the ICF. RESULTS: A random sample of 160 (50%) of 320 eligible studies was included. A total of 148 standardized health status measures were identified. Of 11,283 extracted concepts, 91% could be linked to the ICF. The most used ICF categories for each component were d450 walking (70%) for activities and participation, b525 defecation functions (62%) for body functions, and e399 support and relationships, unspecified (30%) for environmental factors. CONCLUSION: The ICF provides a useful reference to identify and quantify the concepts contained in outcome measures used in stroke trials. Outcome measurement in stroke refers to an enormous variety of concepts; for comparability of research findings agreement on what should be measured is needed.

Activities of Daily Living↗
PubMed2004

Identifying the concepts contained in outcome measures of clinical trials on breast cancer using the International Classification of Functioning, Disability and Health as a reference.

OBJECTIVES: To systematically identify and quantify the concepts contained in outcome measures of clinical breast cancer trials using the International Classification of Functioning, Disability and Health (ICF) as a reference. METHODS: Randomized controlled trials between 1991 and 2000 were located in MEDLINE and selected according predefined criteria. The outcome measures were extracted and the concepts contained in the outcome measures were linked to the ICF. RESULTS: A total of 640 trials were included. Ninety-four different health status questionnaires were extracted. Three questionnaires were breast cancer-specific and 12 cancer-specific. Of 19,692 extracted concepts, 88% could be linked to the ICF. The most used ICF categories within the components body structures, body functions, and activities and participation were structure of the reproductive system (s630), sensations associated with the digestive system (b535), and looking after one's health (d570) with frequencies of 64%, 46% and 14%, respectively. No category of the environmental factors component reached a frequency of 10%. CONCLUSION: The ICF provides a useful reference to identify and quantify the concepts contained in outcome assessment used in clinical breast cancer trials. There seems to be a lack of health concepts evaluating specific aspects of disability and participation in breast cancer. Similarly, environmental factors with an impact on individual life of breast cancer survivors seem to be poorly represented.

Activities of Daily Living↗
PubMedDate not supplied

How does variation in fetal loss affect the distribution of waiting times to conception?

Unmeasured variation has long been a concern in analyses of the waiting time to conception. Recent work by Heckman and Walker (1991) and Trussell and Rodriguez (1990) has underscored the fact that statistical considerations alone cannot discriminate among likely models describing the distribution. Here, we specify a single theoretically important source of heterogeneity, namely variability in intrauterine mortality, and assess its effects on the waiting times to a conception which results in a live birth. We find that the effects on the waiting times to a conception which results in a live birth. We find that the effects of variation in fetal loss are confined to the tail of the distribution. Unless variation in fetal loss is extremely large or a substantial proportion of observed waiting times are initiated at late ages, variation in fetal loss does not appear to explain much variation in conception waits. We conclude that heterogeneity in fetal loss does not explain the variation in fecundability that has been observed for first birth intervals. This conclusion supports the hypothesis that at early ages (below age 35) variation in the waiting time to a fertile conception may largely reflect the proportion of nonsusceptible couples in the population. The analyses suggest that for the purposes of testing theoretically motivated models, future efforts should be directed toward examining reproductive experience after age 35 and toward incorporating information on characteristics of the fertile period as it becomes known.

Abortion, Spontaneous↗
PubMed2004

Annual pattern of human conception in the State of Texas.

A total of 2,828,068 State of Texas singleton conceptions, estimated from the date of the first day of the last menstrual period, were assessed for annual periodicity by multiple-component (1-yr fundamental plus the 6- and 3-month harmonics) Cosinor analysis. An annual pattern (p < 0.001) of conception was detected with a December peak, end of July-beginning of August trough and modest amplitude (total peak-to-trough variation) equal to 13.3% of the yearly mean. Annual patterns (p < 0.005) of generally comparable peak and trough times were also documented for conceptions categorized by maternal marital status, age, ethnicity, years of education, birthplace, and county (Texas-Mexico border vs. non-border) of residence. The amplitude, a measure of the prominence of the annual pattern, varied by race (two-fold greater for non-Hispanic Blacks and Hispanics than non-Hispanic Whites), age (50-60% greater for the 19-year-old and younger group than the 20-29 and 30-44-year-old groups) and maternal education (two-fold greater for those with 0-8 than 13 or more years of schooling). Annual patterns (p < 0.001) in conceptions, generally with December peak and end of July-beginning of August trough, were also detected for neonatal variables categorized by birth weight, birth order, gestational age, and gender. The amplitude of the annual pattern in conceptions varied directly with gestational age and inversely with birth weight class.

Adult↗
PubMed1997

Concepts of fever: recent advances and lingering dogma.

Fever has been a preoccupation of clinicians since medicine's beginning. One might therefore expect that basic concepts relating to this physiological response would be well delineated and that such concepts would be widely known. In fact, only in the past several decades has the febrile response been subjected to scientific scrutiny. As a result of recent scientific investigation, modern concepts have evolved from a perception of fever as nothing more than a rise in core temperature to one in which fever is recognized as a complex physiological response characterized by a cytokine-mediated rise in temperature, as well as by generation of acute-phase reactants and activation of a panoply of physiological, endocrinologic, and immunologic systems. The average clinician appears to have little more than a regrettably rudimentary knowledge of these modern concepts of fever. This symposium summary considers many such concepts that have immediate relevance to the practice of medicine.

Acute-Phase Proteins↗
PubMed2000

New real-time strain imaging concepts using diagnostic ultrasound.

Two real-time strain imaging concepts and systems are presented. Both systems are based on a conventional ultrasound scanner that is connected to a PC with an A/D converter card for real-time data acquisition of rf data. Differential strain between successively acquired rf frames are estimated using phase root seeking. The first concept uses a special real-time implementation of manual elastography. In the second concept, denoted 'vibrography', the static compression is replaced by low-frequency axial vibration of the probe, still operating in quasistatic acquisition mode. The properties of both concepts are discussed with regard to noise and motion artefacts, and it is shown, using simulations and phantom experiments, that both imaging concepts yield the same kind of strain images. Vibrography has the advantage that no manual compression has to be applied, total compression can be very low and some motion artefacts are better suppressed.

Algorithms↗
PubMed1996

Is long-term maintenance of health-related physical activity possible? An analysis of concepts and evidence.

The phenomenon of maintenance of health-related physical activity is explored through an analysis of the underlying concepts and of the existing empirical evidence. The following targets were used for the analysis: (1) the concept of health-related physical activity, (2) the concept of maintenance, (3) common manifestations of maintenance in everyday living, (4) the promotional and behavioral characteristics of health-related physical activity, (5) the known determinants of free-living physical activity, and (6) intervention trials on physical activity in free-living groups. The analyses revealed the inherent resistance to adoption and maintenance of physical activity, particularly that of high-intensity and program-centered activities, the persistence, however, of many simple everyday routines and habits, the multiple determinants discovered for free-living physical activity and a few empirical demonstrations of the successful promotion of the maintenance of physical activity over a year or two. The promotion of the maintenance of health-related physical activity seems thus a distinct possibility provided that (1) the promotional situation is analyzed thoroughly, (2) the activity is chosen carefully with an emphasis on moderation in intensity and integration into the participant's life-style, (3) multiple promotional contacts are used, and (4) support from the participant's social and physical environment is provided. There is a need for more research on the maintenance of health-related physical activity using the stages of change models, behavior modification principles, self-control concepts, the concept of intrinsic motivation and the Relapse model. The method of analysis used here could apply to other health-related behaviors as well.

Attitude to Health↗
PubMed2000

Increasing paternal age is associated with delayed conception in a large population of fertile couples: evidence for declining fecundity in older men. The ALSPAC Study Team (Avon Longitudinal Study of Pregnancy and Childhood).

The impact of male age on fecundity remains controversial. Here, a large population study was used to investigate the effect of paternal age on time to conception. All couples in the Avon Health district expecting a baby between 1 April 1991 and 31 December 1992 were eligible. Questionnaires completed by both the man and the woman at 18 weeks gestation covered specific fertility factors, e.g. parity, paternity, cohabitation and oral contraception; and non-specific factors, e.g. educational achievement, housing, cigarette smoking, alcohol consumption, obesity. Logistic regression was used to identify factors independently related to conception in < or =6 or < or =12 months. Of 8515 planned pregnancies, 74% were conceived in < or =6 months, 14% in the second 6 months and 12% after more than a year. Nine variables, including the age of the woman, were independently related to time to conception. After adjustment for these, the likelihood of conception within 6 or 12 months was lower in older men. Compared to men <25 years old, the adjusted odds ratios (95% confidence interval) for conception in < or =12 months were 0.62 (0.40, 0.98), 0.50 (0.31, 0.81) and 0.51 (0.31, 0.86) in men aged 30-34, 35-39 and > or =40 years respectively.

Adult↗