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PubMed1975

Group psychology and the structural theory: a revised psychoanalytic model of group psychology.

It has been my aim in this paper to revise the existing psychoanalytic theory of group psychology in accordance with current structural concepts. The need for fundamental revision in the existing theory of group organization is demonstrated by its restriction to an oedipal paradigm, which cannot account for the regression to an oral paradigm of group organization during group formation. Freud's explanation of regression in crowds is reviewed. The limitations inherent in Freud's topographic and narcisistic models are demonstrated; irreconcilable contradictions are shown to exist between the two theories. A structural model of group psychology that is free from internal contradictions and provides a unifying explanation for both regression and merging in the crowd is developed. As a consequence of these revisions it is possible to conceptualize preoedipal organizations of group structure in addition to the oedipal paradigm proposed by Freud.

Dependency, Psychological↗
PubMed1993

Beyond the interpersonal circumplex in group psychotherapy: the structure and relationship to outcome of the Individual Group Member Interpersonal Process Scale.

Development of a new scale to measure patient behavior in group psychotherapy, the Individual Group Member Interpersonal Process Scale (IGIPS), is described. This scale captures clinically important aspects of how patients act in group, including how they respond to the other group members. The IGIPS was applied to videotapes of the first four sessions of seven 15-session outpatient therapy groups (52 patients) in the Mental Health Department of a health maintenance organization. The scale was found to have five factors (Activity, Interpersonal Sensitivity, Comfort with Self, Self-Focus, and Psychological Mindedness). Patient behavior that was moderate on two IGIPS dimensions was connected with better outcome than was that of patients with more extreme behavior in either direction.

Adult↗
PubMed2001

[Reconditioning in groups: an effective programme for the rehabilitation of patients with low back pain?].

The article reports on a study in which elements of a group-oriented reconditioning programme for patients with low back pain were incorporated into the routine of an in-patient orthopaedic rehabilitation clinic. The specific elements of the new programme consisted of stable group structures during the whole stay of 3 to 4 weeks, and of 3 to 7 hrs. walks in hilly ground three times a week. The effects of this programme were tested against a standard programme with a mix of passive and active elements using a controlled study design. 92 persons participated in an experimental group and 81 persons in a control group with no significant differences found between the two groups at admission. Effects were measured by means of a physicians' questionnaire and a multidimensional patients' questionnaire (IRES) answered at admission, at discharge, and at six- and twelve-month follow-up. The results of a two-factorial analysis of variance with repeated measures showed that the interaction between group and time on the summary score of the IRES was not significant, although the experimental group showed somewhat better effects at all times of measurement. The discussion focuses on the reasons for this result, among which the unexpectedly good effects in the control group are named, as well as certain difficulties with the implementation of a strongly activity-oriented programme into the course of a "normal" rehabilitation clinic.

Adult↗
PubMed1994

Endotoxemia, complement, and white blood cell activation in cardiac surgery: a randomized trial of laxatives and pulsatile perfusion.

Endotoxin activates complement and white blood cells and all are implicated in the pathologic effects of cardiopulmonary bypass (CPB). We investigated if reduction in intestinal bacterial load with a laxative and/or pulsatile perfusion to improve bowel circulation during CPB reduced endotoxemia and complement and white blood cell activation. Sixty patients were randomized to four groups in a 2 x 2 factorial structure: group 1 (no laxative, nonpulsatile perfusion); group 2 (laxative, nonpulsatile perfusion); group 3 (no laxative, pulsatile perfusion); and group 4 (laxative, pulsatile perfusion). Plasma concentrations of endotoxin, C3a and C5a, and granulocyte elastase (GE) were measured before anesthesia, skin incision, and heparin administration; during CPB (1, 30, 60, 90, and 120 minutes and after protamine administration); and after CPB at 3, 6, 12, 24, and 48 hours and 7 days. In all groups there was a small increase in the concentration of endotoxin (overall from 6 ng/L before CPB to 11 ng/L at 90 to 120 minutes; p < 0.001) and significant increases in C3a, C5a, and GE levels but no significant differences among the groups. Endotoxin levels did not correlate with activation of complement or white blood cells. There was a weak correlation between duration of CPB and levels of C3a (r = 0.14; p < 0.03) and GE (r = 0.25; p = 0.001) but not endotoxin or C5a. There was a general correlation between levels of C3a and GE but not in individual patients. In conclusion, CPB results in statistically significant increases in endotoxin, C3a, C5a, and GE during CPB.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Surgical Procedures↗
PubMed2003

Unfolding pathways of native bacteriorhodopsin depend on temperature.

The combination of high-resolution atomic force microscopy (AFM) imaging and single-molecule force-spectroscopy was employed to unfold single bacteriorhodopsins (BR) from native purple membrane patches at various physiologically relevant temperatures. The unfolding spectra reveal detailed insight into the stability of individual structural elements of BR against mechanical unfolding. Intermittent states in the unfolding process are associated with the stepwise unfolding of alpha-helices, whereas other states are associated with the unfolding of polypeptide loops connecting the alpha-helices. It was found that the unfolding forces of the secondary structures considerably decreased upon increasing the temperature from 8 to 52 degrees C. Associated with this effect, the probability of individual unfolding pathways of BR was significantly influenced by the temperature. At lower temperatures, transmembrane alpha-helices and extracellular polypeptide loops exhibited sufficient stability to individually establish potential barriers against unfolding, whereas they predominantly unfolded collectively at elevated temperatures. This suggests that increasing the temperature decreases the mechanical stability of secondary structural elements and changes molecular interactions between secondary structures, thereby forcing them to act as grouped structures.

Bacteriorhodopsins↗
PubMed1999

The CATH Database provides insights into protein structure/function relationships.

We report the latest release (version 1.4) of the CATH protein domains database (http://www.biochem.ucl.ac.uk/bsm/cath). This is a hierarchical classification of 13 359 protein domain structures into evolutionary families and structural groupings. We currently identify 827 homologous families in which the proteins have both structual similarity and sequence and/or functional similarity. These can be further clustered into 593 fold groups and 32 distinct architectures. Using our structural classification and associated data on protein functions, stored in the database (EC identifiers, SWISS-PROT keywords and information from the Enzyme database and literature) we have been able to analyse the correlation between the 3D structure and function. More than 96% of folds in the PDB are associated with a single homologous family. However, within the superfolds, three or more different functions are observed. Considering enzyme functions, more than 95% of clearly homologous families exhibit either single or closely related functions, as demonstrated by the EC identifiers of their relatives. Our analysis supports the view that determining structures, for example as part of a 'structural genomics' initiative, will make a major contribution to interpreting genome data.

Algorithms↗
PubMed2005

Helpers in a cooperatively breeding cichlid stay and pay or disperse and breed, depending on ecological constraints.

The theory of family-group dynamics predicts that group structure, helping behaviour and social interactions among group members should vary with the opportunities of subordinates to breed independently. We investigated experimentally whether unrelated mature helpers in the cooperatively breeding cichlid Neolamprologus pulcher reduce costly social and cooperative behaviour and choose to disperse and breed independently when offered vacant breeding sites. As predicted by the ecological constraints hypothesis,when breeding substrate was available, (i) helpers spent more time in dispersal areas and it was mainly large helpers that left the group to breed independently; (ii) all helpers invested less in costly submissive behaviours towards other group members and large helpers reduced help, supporting the 'pay-to-stay' hypothesis; and (iii) large helpers, particularly those that dispersed and bred, increased more in body mass in the treatment than those without breeding options, suggesting status-dependent strategic growth of helpers. We conclude that helpers of N. pulcher decide whether to stay and pay or disperse and breed in response to constraints on independent breeding.

Analysis of Variance↗
PubMed1997

Sickness absenteeism from work--a critical review of the literature.

Medically certified absence (absence from work attributed to disease and accident) is an important and convenient index of workers' health and attitudes. It also constitutes the largest part of total absence from work. Depending on the country and on industry and population characteristics, sick-leave accounts for 60-70%, and injuries for another 7-20%. The balance is defined as "healthy-worker absence", taken with or without prior permission or post-facto justification. It is characteristic of the first and last phases of an employee's history at the firm; either before he has time to become a permanent employee and adapt to the local "absence culture", or when he contemplates leaving. On the other hand, certified absence is confirmed by a higher authority, and so it is accepted by management, the insuring institution, and the peer group (which often have to carry the extra workload). This absence belongs to the phase of regular relationships, which both sides seek to maintain. Whether and how often the employee has recourse to certification depends on a number of factors. Those mentioned most often in the literature are: (a) absence--proneness-apparently a defined personality trait (psychological or psychosomatic) leading to repeated absences; (b) poor working conditions; (c) lack of group cohesiveness--members of a well-structured group are upheld by its solidarity and sense of belonging ("esprit de corps"); this is observed in smaller and more closely-knit groups such as shift and group teams, as in the Volvo experiment; (d) quality of the leadership and organizational behavior; (e) job satisfaction--deprivation of recognition, use of abilities, responsibility, and interest have strong psychosomatic repercussion; (f) interaction with external forces, especially marketplace conditions--lack of external demand may restrain absence.

Absenteeism↗
PubMedDate not supplied

En bloc resection for locally advanced cancer of the pancreas: is it worthwhile?

The benefit of radical surgical resection of contiguously involved structures for locally advanced pancreatic cancer is unclear. The aim of this study was to examine patient outcome after extended pancreatic resection for locally advanced tumors and to determine if any subset of extended resection affected outcome. We retrospectively reviewed the records of 116 patients with adenocarcinoma of the pancreas, who underwent extirpative pancreatic surgery between 1987 and 2000. Of the 116 patients, 37 (32%) required resection of surrounding structures (group I), and 79 patients (68%) underwent standard pancreatic resections (group II). In all cases, all macroscopic disease was excised. In group I a total of 46 contiguously involved structures were resected: vascular in 25 patients (54%), mesocolon in 16 (35%) (colic vessels in 3, colon in 13), adrenal in three (7%), liver in one (2%), stomach in one (2%) (for a tumor in the tail of the pancreas), and multiple structures in four. Excision of regional blood vessels included the superior mesenteric vein and/or portal vein in 16, hepatic artery in five, and celiac axis in four. No differences between groups I and II were detected for any of the following parameters: age, sex, history of previous operation, estimated blood loss, or hospital stay. For the entire cohort the morbidity and mortality were 38% and 1.7%, respectively, and these rates were similar in the two groups. Adjuvant therapy was administered to more than 90% of patients in both groups. However, patients in group I were more likely to have received neoadjuvant therapy (76% vs. 42%, P = 0.001). Total pancreatectomy and distal pancreatectomy were more often performed in group I (P = 0.005). Additionally, the median operative time was longer (8.5 hours compared to 6.9 hours (P = 0.0004)). Both groups had similar rates of microscopically positive margins and involved lymph nodes, as well as total number of lymph nodes removed. The median survival was 26 months for patients in group I and 16 months for patients in group II (P = 0.08). The median disease-free survival for groups I and II was 16 months and 14 months, respectively (P = 0.88). In comparing patients in group I, who underwent vascular resection vs. mesocolon (colon or middle colic vessels) resection, the median survival was 26 months and 19 months, respectively (P = 0.12). We were unable to detect a difference in outcome for patients with locally advanced cancers requiring extended pancreatic resections compared to patients with standard resections. En bloc resection of involved surrounding structures, to completely extirpate all macroscopic disease, may be of benefit in selected patients with locally advanced disease, particularly when combined with preoperative chemoradiation therapy.

Adenocarcinoma↗
PubMed1976

Immunochemical studies on bacterial blood group substances. VIII. The structure of oligosaccharides from blood group H-active polysaccharide of Escherichia coli 2B-V.

Blood group H-active polysaccharide has been prepared from "smooth" strain Escherichia coli 2B-V by Freeman's method, alpha-Fucosidase derived from Bacillus fluminans caused the liberation of fucose from this polysaccharide, together with concomitant loss of blood group H activity. The results of quantitative microanalysis, borohydride reduction, the Morgan-Elson reaction and enzymic hydrolysis with betagalactosidase using isolated oligosaccharides obtained by partial acid hydrolysis indicated that the O-specific side chain of the polysaccharide has a pentassaccharide unit which is beta-D-Gal-(1 leads to 3)-D-GalNAc-(1 leads to 3)-D-GalNAc-Fuc with a D-glucose residue bound at some undetermined point on this structure. It was considered that terminal non-reducing fucose of the polysaccharide was liberated by partial acid hydrolysis.

Acetylgalactosamine↗
PubMed1980

Utilization of within-hospital services. A study of the effects of two forms of group practice.

This study examined the effect of group affiliation on the use of technical (length of stay, lab tests, etc.) and clinical (rendering and requesting consultations) resources by physicians practicing within a large acute care hospital. Comparisons in use were made between physicians in 1) a prepaid group practice (Colorado Permanente Medical Group [Kaiser]); 2) a fee-for-service group practice; and 3) "unaffiliated" physicians. Patient data were adjusted whenever possible for patient diagnosis and severity. In comparison to other physicians in the hospital, the prepaid group physicians utilized somewhat fewer technical resources, though the results were not statistically significant. Differences in the use of clinical resources were statistically significant, with the fee-for-service group physicians using consulting services the most and prepaid group physicians using them the least. The results indicate that 1) fee-for-service group structures may reinforce the incentives to share in consultation revenues; 2) prepaid group physicians may experience difficulty becoming integrated into the informal structures of physician practice patterns; and 3) the control of groups over the use of technical hospital resources may be substantially weakened when groups do not own or control the hospitals to which they admit their patients.

Analysis of Variance↗
PubMed1987

Structural conventions for group I introns.

Conventions for nomenclature of structural elements and a standard secondary structure representation for group I introns have been established by workers in the field. These conventions are designed to facilitate effective communication of information concerning the structure and function of these self-splicing introns.

Animals↗
PubMed2003

The tripartite model of anxiety and depression: symptom structure in depressive and hypertensive patient groups.

The structure of self-reported symptoms representative of the tripartite model was examined using data drawn from the Medical Outcomes Study (Tarlov et al., 1989). Participants were persons who had been diagnosed 48 months previously as suffering from either depression (N = 315) or hypertension (N = 403). Results of confirmatory factor analyses were broadly consistent with the tripartite model (L. A. Clark & Watson, 1991). Factors emerged corresponding to each of the 3 posited first-order dimensions of negative affect, positive affect, and physiologic arousal. Nonetheless, some discrepancies were found between the observed data and the hypothesized tripartite model. First, the obtained physiologic arousal factor was best viewed as reflecting nonspecific somatic distress rather than physiologic arousal. Finally, although differentiable in the strictest statistical sense, all three domains were significantly correlated (.36 to.86, absolute value). In particular, contrary to the tripartite model, positive and negative affect covaried markedly (-.81 to -.86). Findings raise issues concerning the utility of the tripartite model as a heuristic framework for enhancing understanding of individual differences in normal mood as well as mood disorders.

Adult↗
PubMed1999

A catalytic mechanism for caspase-1 and for bimodal inhibition of caspase-1 by activated aspartic ketones.

We have evaluated 619 aspartic ketones with 9 different types of prime-side groups (acyloxymethyl, aryloxymethyl, arylthiomethyl, alkylthiomethyl, acylamino-oxymethyl, sulfonylaminomethyl, alpha-ketoamide, alpha-(1-phenyl-3-trifluoromethyl-pyrazol-5-yl)oxymethyl (PTP), and aliphatic ketones) as inhibitors of caspase-1. The inhibitory behaviors could be classified as reversible, inactivating, or bimodal (i.e. reversible inhibition followed by slow inactivation) based on the kinetically observed formation of reversible thiohemiketal complexes and conversion to an irreversible thioether adduct, and the mechanism of any given ketone was only poorly predictable on the basis of leaving group structure and chemistry. Among 201 bimodal inhibitors, the rate of conversion of the reversible thiohemiketal complex to the inactive thioether (k(i)) was strictly first-order, consistent with direct conversion of the thiohemiketal to the thioether with no intermediate collapse to free ketone and thiolate. We have examined 22 crystallographic structures of caspase-1 complexed as a thiohemiketal with the inhibitors from 8 different ketone classes, and found the Cys285S-C-C(alpha)-leaving group dihedral angle to be near either to 60 degrees or to 180 degrees. Only the 180 degrees conformation was permissive for SN2 displacement of the leaving group and, furthermore, positioned His237Ndelta to stabilize developing charge on the leaving group. Among these structures and 19 additional complexes, all showed a strong interaction between His237Ndelta and the ketone or thiohemiketal oxygen. We therefore propose a proteolytic mechanism for caspase-1 involving polarization of the scissile carbonyl by the His237 imidazolium group. During thiohemiketal/thioether conversion (but probably not during peptide hydrolysis), the leaving group is stabilized by the His237 imidazolium.

Caspase 1↗
PubMed1993

The structural determinants of recovery in Wernicke's aphasia.

Recovery of comprehension and total language in 22 Wernicke's aphasics was correlated with lesion size and extent of involvement of certain structures on CT. Recovery rates and outcomes were separately examined using 0-3 months and 0-12 months poststroke language data. Quantitative measures of structural damage were regressed on total aphasia and comprehension outcome measures. Supramarginal and angular gyri appeared to be the most significant structures in recovery in addition to initial severity and lesion size. This was confirmed by using ANOVA to compare the extent of involvement in each postcentral structure among the poor, moderate, and good recovery groups. The superior temporal and middle temporal gyri are less involved in the good recovery group. Structures posteriorly adjacent to Wernicke's area are important for compensation in Wernicke's aphasia and in the accompanying comprehension deficit. Persisting Wernicke's aphasia usually involves the supramarginal and angular gyri in addition to the superior temporal area.

Aged↗
PubMed1999

[Coping and convalescence course after lumbar disk operations].

BACKGROUND: Aim of the present prospective longitudinal study was the statistical foundation and thus further replication of recent findings of Hasenbring [13], who postulated a significant importance of specific, within the psychological pain research long neglected pain coping strategies as risk factors concerning pain chronification: appeals to "stick it out" on the cognitive level and endurance strategies on the behavioural level. METHODS: In contrast to Hasenbring's heterogeneous chronic pain patients sample (first plus repeated surgical or conservative treatment) the present 82 low back pain patients with acute radicular pain and simultaneous lumbar disc prolapse all underwent first time lumbar nucleotomy. Prior to treatment we conducted an extensive psychological and neurological examination. The psychological tests included a general depression scale (Allgemeine Depressionsskala; ADS) and the Kiel Pain Inventory (KPI). Based on these scales a cluster analysis was performed, which allocated patients to four distinct groups resembling the group structure ascertained by Hasenbring [12, 13]: A first group of patients characterized by a positive mood and marked endurance strategies (n=7); another cluster with depressive mood and simultaneous cognitive appeals to stick it out (n=10); a third group of emotionally depressed patients who preferably applied social and physical avoidance strategies in their coping with chronic pain (n=29), plus a last cluster without any psychological risk factors (n=26). RESULTS: As treatment outcome criteria to evaluate the quality of the convalescence process six months later we assessed the pain intensity (11-point self-rating scale), the ability to work, and whether the patients had applied for early retirement or not. Results showed no significant differences in pain intensity between the groups at the 6-month follow up. Concerning the two other outcome variables the two clusters characterized by cognitive or behavioural endurance tendencies turned out to be high risk groups: At the 6-month follow up patients of both groups seemed less likely to return to work. The patients typified by endurance strategies and positive mood had more often applied for early retirement than those patients without psychological risk factors. DISCUSSION: These results corroborate the finding that this subgroup of chronic low back pain patients might indeed carry a bad prognosis and call for further research into this area, especially with regard to rehabilitation potential and facilities of reintegration into working life.

English Abstract↗
PubMed1995

Increasing diversity of animal lectin structures.

The number of animal proteins known to recognize carbohydrates and the number of their biological roles continue to increase. Comparisons of primary structures show that some of the newly described lectins are akin to previously investigated lectins, whereas others represent new structural groups. Progress has been made in understanding structure-function relationships for several lectins in both the old and the new categories.

Animals↗
PubMed2001

The use of olfactory and other cues for social recognition by juvenile pigs.

Social recognition is essential for the maintenance of a stable group structure. Failure to recognise familiar conspecifics in social groups of juvenile pigs may initiate agonistic encounters that can compromise welfare and productivity. Current housing systems may allow build up of atmospheric ammonia that might, in turn, interfere with the olfactory system and compromise olfactory perception. In the present study, 16 juvenile pigs were housed in fresh air while another 16 pigs were kept in an ammoniated atmosphere (approximately 36ppm) for 1 week prior to test and another week during testing. We then assessed the role of olfaction in social recognition and determined whether chronic exposure to ammonia compromised discrimination based on olfactory perception by comparing the pigs' responses to selected cues from a familiar and an unfamiliar pig presented simultaneously in separate chambers of a modified Y-maze in each of two test situations (near, remote). Visual, auditory, olfactory, and tactile cues were all provided in the "near" test situation; here, the stimulus pigs were presented in two separate chambers behind clear perspex walls containing an aperture that allowed nose-to-nose contact between the test and stimulus pigs. On the other hand, the "remote" test provided only olfactory cues via air passed from the chambers containing the stimulus pigs into the test chamber. Each test lasted 5min and the pigs' behaviour was recorded via overhead video cameras; we then measured the accumulated times spent near and the numbers of visits made to the familiar and the unfamiliar stimulus pigs as well as the transitions between them. Overall, pigs made more visits to and spent significantly longer near both the stimulus pigs in the near test than in the remote one (ANOVA, P<0.001). They also made more transitions between the stimuli in the former test than the latter (P<0.001). Pigs from both the ammonia and the fresh-air treatment groups showed social discrimination. However, pigs that had received chronic exposure to ammonia visited the familiar pig more often and spent longer near it than the unfamiliar one regardless of the test situation (P<0.05) whereas those reared in fresh air spent longer near the unfamiliar animal (P<0.05). The present results suggest that pigs from both treatment groups employed olfactory cues in social recognition, but that chronic exposure to ammonia did not interfere with this ability. However, ammonia treatment seemingly affected social preferences, thus indicating an unknown and more fundamental effect of living in ammoniated atmospheres.

Journal Article↗