| 1. |
- Bengtsson, Magnus Wilhelm, 1977-
(författare)
-
Effects of Orexins, Guanylins and Feeding on Duodenal Bicarbonate Secretion and Enterocyte Intracellular Signaling
- 2008
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The duodenal epithelium secretes bicarbonate ions and this is regarded as the primary defence mechanism against the acid discharged from the stomach. For an efficient protection, the duodenum must also function as a sensory organ identifying luminal factors. Enteroendocrine cells are well-established intestinal “taste” cells that express signaling peptides such as orexins and guanylins. Luminal factors affect the release of these peptides, which may modulate the activity of nearby epithelial and neural cells.The present thesis considers the effects of orexins and guanylins on duodenal bicarbonate secretion. The duodenal secretory response to the peptides was examined in anaesthetised rats in situ and the effects of orexin-A on intracellular calcium signaling by human as well as rat duodenal enterocytes were studied in vitro.Orexin-A, guanylin and uroguanylin were all stimulants of bicarbonate secretion. The stimulatory effect of orexin-A was inhibited by the OX1-receptor selective antagonist SB-334867. The muscarinic antagonist atropine on the other hand, did not affect the orexin-A-induced secretion, excluding involvement of muscarinic receptors. Orexin-A induced calcium signaling in isolated duodenocytes suggesting a direct effect at these cells. Interestingly, orexin-induced secretion and calcium signaling as well as mucosal orexin-receptor mRNA and OX1-receptor protein levels were all substantially downregulated in overnight fasted rats compared with animals with continuous access to food. Further, secretion induced by Orexin-A was shown to be dependent on an extended period of glucose priming.The uroguanylin-induced bicarbonate secretion was reduced by atropine suggesting involvement of muscarinic receptors. The melatonin receptor antagonist luzindole attenuated the secretory response to intra-arterially administered guanylins but had no effect on secretion when the guanylins were given luminally. In conclusion, the results suggest that orexin-A as well as guanylins may participate in the regulation of duodenal bicarbonate secretion. Further, the duodenal orexin system is dependent on the feeding status of the animals.
|
|
| 2. |
- Brändström, Sven, 1952-, et al.
(författare)
-
Further development of the Temperament and Character Inventory
- 2001
-
Ingår i: Psychological Reports. - 0033-2941 .- 1558-691X. ; 93, s. 995-1002
-
Tidskriftsartikel (refereegranskat)abstract
- The Temperament and Character Inventory is an internationally used personality questionnaire based on Cloninger’s psychobiological theory of personality. Given some limitations of Version 9 a revised version was developed. The structural equivalence of the two versions was demonstrated from a cross-cultural perspective with 309 and 173 healthy volunteers from Sweden and Germany, respectively, who completed both versions in one session. In testing for the replicability of the factors across both samples as well as across both versions, an orthogonal Procrustes rotation method was used. The reliability coefficients for the revision were higher than the former version for both samples. The factor structures of the inventory remain highly equivalent across cultures and across versions. The results indicate a cross-cultural transferability of the Temperament and Character dimensions of the inventory. The stability and the validity of the 7-factor model of personality, as suggested by Cloninger, are supported. The Temperament and Character Inventory-Revised represents an important and useful method for the assessment of personality.
|
|
| 3. |
- Brändström, Sven, 1952-, et al.
(författare)
-
Further development of the temperament and character inventory
- 2003
-
Ingår i: Psychological Reports. - 0033-2941 .- 1558-691X. ; 93:3 II, s. 995-1002
-
Tidskriftsartikel (refereegranskat)abstract
- The Temperament and Character Inventory is an internationally used personality questionnaire based on Cloninger's psychobiological theory of personality. Given some limitations of Version 9 a revised version was developed. The structural equivalence of the two versions was demonstrated from a cross-cultural perspective with 309 and 173 healthy volunteers from Sweden and Germany, respectively, who completed both versions in one session. In testing for the replicability of the factors across both samples as well as across both versions, an orthogonal Procrustes rotation method was used. The reliability coefficients for the revision were higher than the former version for both samples. The factor structures of the inventory remain highly equivalent across cultures and across versions. The results indicate a cross-cultural transferability of the Temperament and Character dimensions of the inventory. The stability and the validity of the 7-factor model of personality, as suggested by Cloninger, are supported. The Temperament and Character Inventory-Revised represents an important and useful method for the assessment of personality.
|
|
| 4. |
- Brändström, Sven, 1952-
(författare)
-
Personality and its complexity : An investigation of the Swedish version of the Temperament and Character Inventory
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In former days the descriptions of personality were based on typologies, reflecting the view that people do not change over time and so have a stable, life-long personality type. Later on exclusive categories were created, but during recent times the understanding of personality has changed due to more dimensional and dynamic thinking.Cloninger’s personality theory integrates concepts and research findings from neuroanatomy, neurophysiology of behavior and learning, and from developmental, social and clinical psychology. It is postulated that the behavioural systems of temperament and character are related to two major neural systems for the adaptation of experiences on various levels. The continuous interaction between temperament and character affects the personality development in both directions; temperament impacts upon character and vice versa during life.The development of the TCI was founded on the development of the biosocial theory of personality, which in turn stimulated the further development of the theory. Unfortunately this theory-based approach is not commonly used in the development of personality measurements. The development of a personality questionnaire on the basis of the theory must be viewed as a significant challenge, and this prompted my interest in dealing with and learning more about this personality assessment method.The objectives of this thesis were a critical evaluation of Cloninger’s theory; a test of its applicability in psychiatric science; and an attempt to contribute to its development.The main findings of our investigations can be described as follows:The adaptation of the Swedish version of the Temperament and Character Inventory (TCI) was successful and the seven factor structure of Cloninger’s biopsychological theory of personality theory was mainly confirmed by the Swedish normative data and by cross-cultural comparisons between data from Germany, Sweden and the U.S.A.The results concerning internal consistency and factor structure further underline that the adult version of the TCI is unsuitable for use in adolescents before age of 17 years. For the adolescents the junior TCI is recommended.Furthermore temperament dimensions seem to be more stable over time compared to the character dimensions. The gender and age differences found suggest that both have to be taken into account in research and clinical application.The results from our studies suggested that the Temperament and Character Inventory (TCI) has to be evaluated as a useful tool within the process of validation of diagnosis of a Personality Disorder (PD), especially in clinical practice where it is often difficult to recognise all a patient’s personality disturbances during a short time. Use of the TCI is likely to improve understanding, classification, and subsequently the interpretations in clinical settings.
|
|
| 5. |
- Brändström, Sven, 1952-, et al.
(författare)
-
Swedish normative data on personality using the Temperament and Character Inventory
- 1998
-
Ingår i: Comprehensive Psychiatry. - 0010-440X .- 1532-8384. ; 39:3, s. 122-128
-
Tidskriftsartikel (refereegranskat)abstract
- The Temperament and Character Inventory (TCI) is a self-report personality questionnaire based on Cloninger's psychobiological model of personality, which accounts for both normal and abnormal variation in the two major components of personality, temperament and character. Normative data for the Swedish TCI based on a representative Swedish sample of 1,300 adults are presented, and the psychometric properties of the questionnaire are discussed. The structure of the Swedish version replicates the American version well for the means, distribution of scores, and relationships within the between scales and subscales. Further, the Swedish inventory had a reliable factor structure and test-retest performance. The results of this study confirm the theory of temperament and character as a seven-factor model of personality.
|
|
| 6. |
- Brändström, Sven, 1952-, et al.
(författare)
-
The Swedish Version of the Temperament and Character Inventory (TCI) : A Cross-Validation of Age and Gender Influences
- 2008
-
Ingår i: European Journal of Psychological Assessment. - : Hogrefe Publishing Group. - 1015-5759 .- 2151-2426. ; 24:1, s. 14-21
-
Tidskriftsartikel (refereegranskat)abstract
- In order to establish new norms of the Swedish version of the Temperament and Character Inventory (TCI), data from 2,209 Swedish individuals (age between 13 and 80) was analyzed. The second aim was to evaluate the impact of age and gender on the questionnaire scores. The third aim was to investigate whether the TCI can be meaningfully applied to adolescents in personality assessment as a basis for further research and clinical studies. Age and gender showed independent effects on personality dimensions, which implies that age and gender specific norms have to be established for the TCI. Furthermore, the results in terms of inconsistencies in the correlational and factorial structure, as well as low internal consistency scores in the younger age groups, suggest that the adult version of the TCI should not be applied below the age of 17; for these age groups we recommend the use of the junior TCI (JTCI). The inventory is under further development and several items are in need of revision in order to create less complicated formulations, enabling an improvement in the psychometrics.
|
|
| 7. |
- Brändström, Sven, et al.
(författare)
-
The Swedish version of the Temperament and Character Inventory (TCI)
- 2008
-
Ingår i: European Journal of Psychological Assessment. - Göttingen : Hogrefe & Huber Publishers. - 1015-5759 .- 2151-2426. ; 24:1, s. 14-21
-
Tidskriftsartikel (refereegranskat)abstract
- In order to establish new norms of the Swedish version of the Temperament and Character Inventory (TCI), data from 2,209 Swedish individuals (age between 13 and 80) was analyzed. The second aim was to evaluate the impact of age and gender on the questionnaire scores. The third aim was to investigate whether the TO can be meaningfully applied to adolescents in personality assessment as a basis for further research and clinical studies. Age and gender showed independent effects on personality dimensions, which implies that age and gender specific norms have to be established for the TCI. Furthermore, the results in terms of inconsistencies in the correlational and factorial structure, as well as low internal consistency scores in the younger age groups, suggest that the adult version of the TCI should not be applied below the age of 17; for these age groups we recommend the use of the junior TCI (JTCI). The inventory is under further development and several items are in need of revision in order to create less complicated formulations, enabling an improvement in the psychometrics.
|
|
| 8. |
|
|
| 9. |
- Carlsson, Anna, et al.
(författare)
-
Identification of a susceptibility locus for migraine with and without aura on 6p12.2-p21.1
- 2002
-
Ingår i: Neurology. - : Lippincott Williams & Wilkins. - 0028-3878 .- 1526-632X. ; 59:11, s. 1804-1807
-
Tidskriftsartikel (refereegranskat)abstract
- Migraine is the most common type of chronic episodic headache. To find novel susceptibility genes for familial migraine with and without aura, a genomewide screen was performed in a large family from northern Sweden. Evidence of linkage was obtained on chromosome 6p12.2-p21.1, with a maximum two-point lod score of 5.41 for marker D6S452. The patients with migraine shared a common haplotype of 10 Mb between markers D6S1650 and D6S1960.
|
|
| 10. |
- Engström, Christer, et al.
(författare)
-
Bipolar disorder I. Temperament and character
- 2004
-
Ingår i: Journal of Affective Disorders. - Amsterdam : Elsevier. - 0165-0327 .- 1573-2517. ; 82:1, s. 131-134
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The nature of the relationship between personality and bipolar affective disorders is an important but unanswered question. Methods: We have studied personality in bipolar patients by using the Temperament and Character Inventory (TCI). TCI were administered to 100 euthymic bipolar patients and 100 controls from the normal population.Results: Bipolar patients were significantly higher in harm avoidance (HA) and lower in reward dependence (RD), self-directedness (SD), and cooperativeness (CO) than controls. Bipolar patients are more fatigable, less sentimental, more independent, less purposeful, less resourceful, less empathic, less helpful, less pure-hearted, and have less impulse control than controls. Bipolar II patients are more impulsive, more fatigable, less resourceful, and have less impulse control than bipolar I patients.Limitations: Our results are limited to euthymic bipolar patients and cannot be generalized to affective disorders.Conclusions: Even when clinically euthymic on lithium maintenance, bipolar patients continue to have a characteristic cognitive deficit. This is in agreement with cognitive theories about cognitive deficits in depression that are regarded as important vulnerability factors in mood disorders.
|
|
