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T Kessler

Publications and source records attributed to T Kessler.

At least 37 records · Page 2Linked to original sources
PubMed1999

Stability and change in longitudinal water-level task performance.

Three longitudinal samples of children (N = 481), 8 to 16 years old, were assessed 3 times at yearly intervals on 8 water-level items. The within-child change in task performance over age is viewed as a stochastic process of the child changing or remaining in 1 of 3 latent (strategy) states: (a) bottom-parallel responders, (b) random responders, or (c) accurate responders. A random-effects binomial mixture distribution is used to model performance at each age. Change over age is gauged by a stochastic transition model. Although there was improvement in task performance over age, the more general finding is that strategy stability, not change, is most typical.

Adolescent↗
PubMed1999

Strategies to cope with negative social identity: predictions by social identity theory and relative deprivation theory.

Predictions by social identity theory (SIT) and relative deprivation theory (RDT) concerning preferences for strategies to cope with a negative in-group status position were tested. The focus of the present research was a comparison of the theories regarding their differential patterns of prediction. For this purpose, a natural sample within a specific historical situation was investigated: East Germans after the German unification. First, the predictive power of SIT and RDT variables was tested separately. In a second step, a possible integration of the theories was addressed. Combining the SIT variables and RDT variables led to an integrated model indicating a differential pattern of prediction for intergroup strategies. The RDT components explained the collective responses, whereas SIT constructs were related to individual strategies.

Adaptation, Psychological↗
PubMed1998

N-acetyl-beta-D-glucosaminidase excretion in healthy children and in pediatric patients with urolithiasis.

Hyperoxaluria was reported to induce renal damage, probably due to toxic effects on renal tubules. Such tubular damage might be expressed by an increase in urinary excretion of marker enzymes such as N-acetyl-beta-D-glucosaminidase (NAG). We set out to examine a possible relationship between the excretion of NAG and that of urinary lithogenic and stone-inhibitory substances by analyzing 24-h urine specimens from 56 children with urolithiasis and 25 healthy children with normal renal function and without a history of urolithiasis. The NAG excretion was higher in patients with urolithiasis (3.5 +/- 0.51 U/g creatinine) as compared with healthy subjects (1.33 +/- 0.14 U/g creatinine, P < 0.05). A positive correlation between NAG and oxalate excretion was observed in female patients (r = 0.56: P < 0.01). In conclusion, the increase in urinary NAG in children with urolithiasis might express renal tubular damage. It seemed, however, not to be specifically related to the excretion of a single lithogenic substance.

Acetylglucosaminidase↗
PubMed1998

Quality of life in adult patients with acute myeloid leukemia receiving intensive and prolonged chemotherapy -- a longitudinal study.

Intensification of treatment for acute myeloid leukemia (AML) in adult patients resulted in a substantial improvement in long-term prognosis. Therefore, the assessment of quality of life (QL) of patients undergoing treatment is of growing interest. This study was designed to evaluate QL in patients with AML treated according to the protocol of the German AML-Cooperative Group (Münster, Germany). The EORTC QLQ-C 30 questionnaire was used to analyze QL throughout therapy, evaluating defined specific parameters at 12 different time-points. Sixty-one patients were recruited within the first 30 months of the study. Those 28 patients who have completed the course of inpatient treatment (n=28) are evaluated for changes in the conceptually distinct QL domains: Physical Functioning (P<0.001), Role Functioning (P=0.001), Emotional Functioning (P < 0.001) and Social Functioning (P=0.007) improve significantly from beginning of chemotherapy to the end of inpatient treatment. Individual assessment of Global Health Status and Subjective QL improves significantly over the same time (P< 0.001). At the end of inpatient treatment patients suffer significantly less from fatigue, nausea/emesis, loss of appetite and sleep disturbance (P < 0.001). Although most patients with AML eventually relapse, the evaluation of QL in patients undergoing treatment shows that subjective benefit outweighs the adverse effects of antileukemic therapy.

Acute Disease↗
PubMed1996

Decomposing Water-Level Responses: Field Effects as Separate Influences

A previous study on water-level task performance using binomial mixture analyses showed that subgroups of subjects could be identified which used different response rules. Some subjects used a bottom parallel rule, others used a random-like rule, and still others used the correct response rule. The present study relates the water-level task performance of these subgroups to field effect influences. Subjects were 604 children and adolescents aged 7 to 15 years who responded to eight water-level and eight rod-and-frame task items. The results show that the water-level response distribution is influenced by the frame of the vessel. These field effects are relatively small if subjects maintain a fixed response rule, and they are large if subjects use a nonfixed random rule. Both field effects and response rules contribute to the behavior of subjects responding to water-level task items.

Journal Article↗
PubMed1996

[C6 fatal trans-vertebral dislocation fracture with tracheal lesion in Bechterew disease. A case presentation].

A fracture of the cervical spine is a dangerous and life-threatening injury in patients suffering from ankylosing spondylitis. A 71-year-old motorist with a long history of ankylosing spondylitis was injured during a car accident. A rare transverse fracture through the body of C6 occurred and in addition a lesion of the trachea was found. This combination of injuries is described for the first time. Special problems relating to the initial rescue, diagnosis and treatment are discussed according to the literature. The necessity of handling the cervical spine with extreme caution during all medical procedures, taking into account the kyphotic deformity is stressed.

Aged↗
PubMed1996

[Quality of life and coping with illness in patients with acute myeloid leukemia].

Advances in chemotherapy significantly prolong survival of patients with acute myeloid leukemia (AML) and may cure a significant percentage of patients. Therefore, the assessment of quality of life (QL) of patients undergoing chemotherapy is of growing interest. This study was designed to evaluate QL in patients with AML treated according to the protocol of the German AML-Cooperative Group (Münster, FRG). Based on conceptual, methodological and practical criteria, the EORTC-QLQ C 30 questionnaire was used. In addition, patients' coping strategies were assessed by the FQCI. Patients' individual perception of their disease and therapy was evaluated by a semi-structured interview. Currently, 61 patients are enrolled in the protocol. For those patients having completed the course of inpatient treatment, individual assessment of Global Health Status and Subjective QL improves significantly. The content analysis of the interviews shows to what extent aspects of the inpatient setting influence patients' QL. Although only a minority of patients with AML remain in continuous complete remission, the evaluation of QL in patients undergoing treatment shows that subjective benefit outweighs the effects of antileukemic therapy.

Adaptation, Psychological↗
PubMed1995

Rolipram increases cyclic GMP content in L-arginine-treated cultured bovine aortic endothelial cells.

Cultured bovine aortic endothelial cells only contain two cyclic nucleotide phosphodiesterases isoforms: PDE II (cyclic GMP stimulated) and PDE IV (rolipram sensitive). The effects of cilostamide or rolipram alone or together, on cyclic AMP and cyclic GMP levels, were measured in indomethacin-treated endothelial cells alone or in the presence of nitric oxide (NO) modulators. In all conditions, cyclic AMP levels were potently increased (8-13-fold) only when PDE II and PDE IV inhibitors were given together. Cyclic GMP levels were not modified by these PDE inhibitors in control and NG-nitro-L-arginine-methyl ester-treated cells. But surprisingly, in L-arginine-treated cells, cyclic GMP content was increased by 42% by rolipram alone, and combination of rolipram with cilostamide resulted in a further increase in cyclic GMP content (to 153% compared to control cells). These results suggest that in presence of the NO synthase substrate (L-arginine), an increase in cyclic AMP level may upregulate the L-arginine/NO/cyclic GMP pathway.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1994

[Follow-up of fracture healing--indications and clinical relevance of direct radiographic magnification in comparison with conventional roentgen imaging].

Comparison of 83 magnification radiographs with corresponding conventional X-rays showed that direct radiographic magnification (DIMA) yielded additional information in 39 cases (47%), which had implications for the treatment in 19 cases (22.9%). In 11 cases callus was first visualized in magnification radiography; the earliest evidence of callus was found 14 days after surgery. Since magnification radiography means the region that can be examined is smaller, conventional radiographs were necessary in 32.5% of cases to find the position of the fracture in long bones. For statistical evaluation interobserver analysis was performed, anatomical and pathological structures being graded according to four levels. Magnification radiography proved superior in all structures examined. Magnification radiography can be recommended as an additional method to monitor fracture healing. Computed radiography was used together with magnification radiography to reduce the radiation dose and to perform image processing including simulation of conventional technique and edge enhancement. DIMA is a valuable tool in the evaluation of fracture stability and in the adjustment of distraction rates in limb-lengthening procedures.

Adult↗
PubMed1993

[The cell response of rat esophagus after intraluminal irradiation with Nd-YAG-laser (1064 nm) after various postoperative times: a light and electron microscopic study].

The esophagi of Wistar rats were irradiated by a Nd-YAG-laser and studied by light and transmission electron microscopy immediately, 2 days and 14 days after the operation. In the immediate group the lasercentre showed a destruction of the stratified epithelium. On the contrary the cells and fibres of the underlying connective tissue were hardly affected. In the lasercentre we have found occlusion of microvascular lumina. Both the layer of smooth muscular tissue and the layer of skeletal muscular tissue showed defects in their myofilaments and altered nuclei. The damage of the skeletal muscle fibres extended up to 4 mm distant from the lasercentre. After 2 days a migrating epithelial sheet was present below the necrotic epithelium and an inflammatory reaction was found in the connective tissue. After 14 days a new regenerated epithelium and an underlying granulation tissue had caused a stenosis of the esophageal lumen. The smooth and striated muscle fibres also showed signs of regeneration. We assume a high regenerative capacity of all involved tissues.

Animals↗
PubMed1991

The calmodulin-binding domain mediates the self-association of the plasma membrane Ca2+ pump.

Dimerization (oligomerization) of the plasma membrane Ca2+ pump increases its activity (Kosk-Kosicka, D., Bzdega, T., and Wawrzynow, A. (1989) J. Biol. Chem. 264, 19495-19499). Fluorescence titration on preparations of the purified eosin-labeled human erythrocyte ATPase has been used to monitor the oligomerization process. Calmodulin inhibits oligomerization, although it can bind to the oligomerized enzyme. Synthetic peptides corresponding to the calmodulin-binding domain of the pump stimulate its ATPase activity, indicating the formation of heterooligomers of the peptides with the pump. The oligomerization is prevented by the preincubation of the ATPase with calmodulin. Polyclonal antibodies against the synthetic calmodulin-binding domain inhibit its basal and its calmodulin-stimulated ATPase activity and prevent the formation of the oligomers. ATPase preparations truncated at the COOH terminus with calpain to a fragment of 124 kDa which does not contain the calmodulin-binding domain fail to oligomerize with the intact ATPase. The results show that the calmodulin-binding domain mediates the oligomerization of the Ca2+ pump.

Amino Acid Sequence↗