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H Stubbe

Publications and source records attributed to H Stubbe.

14 recordsLinked to original sources
PubMed2005

Metal concentrations in soil and seepage water due to infiltration of roof runoff by long term numerical modelling.

The qualitative effects of stormwater infiltration on soil and seepage water are investigated with long term numerical modelling. The retention behaviour of different soils and materials used in infiltration devices is determined with batch and column tests. Results of the laboratory tests are adsorption isotherms which represent input data for numerical transport modelling. The long term simulations are performed with combinations of different solutions (types of roof runoff) and infiltration devices (swale and trench) under different hydrogeological conditions. The presented results contain the infiltration of low polluted roof runoff, runoff from a roof with zinc sheets and from a roof with copper sheets concerning the heavy metals zinc, copper and lead. The increase of concentrations in the infiltration body is high. For the infiltrated water, the results show a migration to groundwater only for the low adsorbing soil.

Adsorption↗
PubMed2004

New approach to an ovine model of hypodynamic endotoxaemia.

BACKGROUND AND OBJECTIVE: Since the moribund hypodynamic phase of septic shock has primarily been studied in small animal models, the objective of this study was to investigate the usefulness of infusing Salmonella typhosa endotoxin at incrementing doses to establish an ovine model of hypodynamic endotoxaemia. METHODS: In a prospective laboratory experiment, eight adult ewes were instrumented for a chronic study. Following a baseline measurement in the healthy state, a continuous endotoxin infusion was started with 10 ng kg(-1) min(-1) and was doubled every hour seven times. Haemodynamics, key variables of oxygen transport, and arterial lactate concentrations were determined every hour. RESULTS: In a dose-dependent manner, endotoxin infusion caused pulmonary hypertension, decreased cardiac output and mean arterial pressure, increased heart rate, and to a certain extent, systemic vascular resistance index. Following 4h of endotoxaemia, the maximum decrease in cardiac output occurred (4.8+/-0.2 vs. 7.6+/-0.3 Lmin(-1); P < 0.001). This was accompanied by tissue dysoxia, represented by decreases in oxygen delivery (797+/-20 vs. 1041+/-28 mLmin(-1)), oxygen consumption (277+/-14 vs. 396+/-15 mLmin(-1)) and oxygen extraction rate (0.35+/-0.01 vs. 0.38+/-0.01%; each P < 0.01), as well as an increase in arterial lactate concentration (1.7+/-0.1 vs. 0.7+/-0.1 mmolL(-1); P < 0.05). CONCLUSIONS: This large animal model may be helpful to study the pathophysiology responsible for cardiovascular failure, and also new therapeutic approaches relevant to management of hypodynamic circulation in the common setting of progressed systemic inflammation.

Animals↗
PubMed2000

Polymeric IgA is superior to monomeric IgA and IgG carrying the same variable domain in preventing Clostridium difficile toxin A damaging of T84 monolayers.

The two exotoxins A and B produced by Clostridium difficile are responsible for antibiotic-associated enterocolitis in human and animals. When added apically to human colonic carcinoma-derived T84 cell monolayers, toxin A, but not toxin B, abolished the transepithelial electrical resistance and altered the morphological integrity. Apical addition of suboptimal concentration of toxin A made the cell monolayer sensitive to toxin B. Both toxins induced drastic and rapid epithelial alterations when applied basolaterally with a complete disorganization of tight junctions and vacuolization of the cells. Toxin A-specific IgG2a from hybridoma PCG-4 added apically with toxin A alone or in combination with toxin B abolished the toxin-induced epithelial alterations for up to 8 h. The Ab neutralized basolateral toxin A for 4 h, but not the mixture of the two toxins. Using an identical Ab:Ag ratio, we found that recombinant polymeric IgA (IgAd/p) with the same Fv fragments extended protection against toxin A for at least 24 h in both compartments. In contrast, the recombinant monomeric IgA counterpart behaved as the PCG-4 IgG2a Ab. The direct comparison between different Ig isotype and molecular forms, but of unique specificity, demonstrates that IgAd/p Ab is more efficient in neutralizing toxin A than monomeric IgG and IgA. We conclude that immune protection against C. difficile toxins requires toxin A-specific secretory Abs in the intestinal lumen and IgAd/p specific for both toxins in the lamina propria.

Antibody Specificity↗
PubMed2000

Molecular studies of the intestinal mucosal barrier physiopathology using cocultures of epithelial and immune cells: a technical update.

Peyer's patch lymphocytes cocultured with Caco-2 cells trigger the phenotypic conversion of enterocytes into cells that express morphological and functional M-cell properties. We report a technical update for setting up this model, which will enable the study of M-cell biology, the identification by biochemical approaches of molecules involved in the interaction of microorganisms with M cells, and the development of vectors that would efficiently target the mucosal immune system.

Animals↗
PubMed1995

Differential induction of stress proteins and functional effects of heat shock in human phagocytes.

Induction of specific heat shock (HS) proteins (HSP) has been described as a response of human monocytes to phagocytosis, and HSP may play protective roles in infection and immunity. Here we compared the stress response in monocytes and polymorphonuclear neutrophils during exposure to the classical inducers of HSP, i.e., HS and cadmium. We also investigated the stress response in these two phagocytic cells after particulate (phagocytosis) and nonparticulate [f-Met-Leu-Phe (FMLP)] activation of the respiratory burst enzyme NADPH oxidase. HS and cadmium induced stress protein synthesis in both cell types. In contrast, phagocytosis induced HSP in monocytes only, while FMLP did so in neutrophils only. This differential regulation of stress proteins might relate to physiological and functional differences between monocytes and neutrophils. With respect to functional effects of HS, we examined, in human monocytes and in neutrophils, the effect of HS on NADPH oxidase-mediated O2- generation as well as on phagocytosis, bacterial killing, and superoxide dismutase (SOD) activity. In monocytes, as in neutrophils, NADPH oxidase activity was inhibited by HS, while thermotolerance prevented this inhibition. Phagocytosis and bacterial killing were unaltered by HS. SOD activity transiently increased in monocytes but decreased in neutrophils upon exposure to HS. These observations indicate differential induction of HSP in human phagocytes and differential regulation of phagocytes' functions by HS.

Cadmium↗
PubMed1995

[Prolegomena on transcultural pediatric psychotherapy].

In a first step the concept of "transcultural child psychotherapy" is explained. Based on an analysis on the demand for a transcultural child psychotherapy in Germany the necessity for its development is pointed out. Names of institutions and persons suitable for transcultural child psychotherapy are given. A systematic attempt follows to integrate the transcultural point of view into general strategies and intervention techniques of child psychotherapy, stressing the psychoanalytical, client-centered and behaviour therapeutic approach. Specific problems as non-verbal, verbal and diagnostic aspects in transcultural child psychotherapy as well as toys are briefly mentioned. Problem groups of a special interest of a transcultural child psychotherapy (e.g. asylum seeking, migrant, persecuted, sold, and adopted children) are mentioned and pointed out to as specific risk groups. The essay ends with questions regarding the effectiveness of transcultural child psychotherapy and with an outlook into further research activities.

Adolescent↗
PubMed1993

Heat shock in human neutrophils: superoxide generation is inhibited by a mechanism distinct from heat-denaturation of NADPH oxidase and is protected by heat shock proteins in thermotolerant cells.

Independently of the stimulating agent used, generation of O2- by human neutrophils is transiently inhibited when the cells have been exposed to elevated temperatures. This phenomenon is concomitant with the synthesis of heat shock proteins (HSPs). We have investigated a possible relationship between HSPs and modulation of NADPH oxidase activity in human neutrophils exposed to heat. HSPs were not involved in the inhibition of O2- generation since 1) in enucleated cytoplasts, which are unable to synthesize proteins, the generation of O2- was inhibited after exposure to 43 degrees C, 2) using actinomycin D (Act D) in intact cells, it was possible selectively to inhibit the synthesis of HSPs without modifying the inhibition of NADPH oxidase activity that followed HS. Furthermore, the recovery of NADPH oxidase activity was not under the control of HSPs because the enzyme recovered as well in Act D-treated neutrophils. The NADPH oxidase activity was reconstituted in a cell-free assay by combining the cytosol with the plasma membrane-enriched fraction in the presence of arachidonic acid (AA) and NADPH. Subcellular fractions obtained from control or heated neutrophils exhibited similar oxidase activities suggesting that heat exposure did not induce denaturation of the oxidase components but rather altered the mechanisms of translocation and/or assembly of these components with the plasma membrane. This hypothesis was supported by the inhibition of the granule release in heated cells, a process which also requires translocation and association fusion with the plasma membrane. On the other hand, preexposure of neutrophils to HS prevented the inhibition of O2- generation during a second challenging HS. This acquired thermotolerance was abolished when the synthesis of HSPs was inhibited during the first HS with Act D, indicating a direct relationship between protection of O2- generation and synthesis of HSP. Here we demonstrate that synthesis of HSPs and inhibition or recovery of NADPH oxidase activity are concomitant but unrelated phenomena. In contrast, accumulation of HSPs in thermotolerant neutrophils appeared to play an important role in the prevention of NADPH oxidase inhibition. These results provide further insights into the behavior of human neutrophils and NADPH oxidase upon heat injury.

Cell Degranulation↗
PubMed1989

[Widowhood and grief reaction in Brazil. A pilot study].

Following a short introduction to transcultural research on widow(er)hood and mourning, the author reports on a Brazilian pilot study in which the reactions to mourning, social relationships, psychosomatic complaints, the tendency toward depression and suicide, etc., are studied in 26 Brazilians who have lost their partners. The results here, as in earlier studies by the same author, show that this group is distinctly "at risk". Finally, an "impact system of widow(er)hood" is developed that establishes the relationship between economic, sociocultural, psychological and somatic factors and the decisive experience of the death of a partner.

Aged↗
PubMed1976

[Psychotherapeutic function of the South American medicine man].

Observing the medicine man system in South America from a psychological point of view, the function of the medicine man can be characterized as psychohygienic or psychotherapeutic; that is to say he employs many methods similar to modern psychotherapeutic ones. We know from many ethnological field research reports that the medicine man employs in his healing procedures - among other things - dream interpretation, (auto-) hynosis, and healing suggestion, advises the sick, uses imaginative techniques, and initiates group catharsis, i.e. he treats his patients by psychological means. The psychic disturbances which he treats concern less the individual but much more often the whole group. Here the medicine man must work as a regulator and valve for the group and try to equalize, to prevent and to heal all disturbances within the collective.

Dreams↗
PubMedDate not supplied

[Psychotherapy in Brazil].

Present conditions in Brazil are characterized by sharp contrasts and rapid social changes. Modern Brazilian civilisation has its roots in Indian, Portuguese and African cultures, which have grown together in the course of many years to form a harmonious union of civilisations. The Indian and Afro-Brazilian elements of this civilisation in particular have brought about a great number of syncretistic cults, hitherto scarcely explored; such as Candomblé, Umbanda, Macumba and Spiritualism, all of which, together with a vigorously active folklore, exert an important psychohygienic function. The institutions created within these cults provide a ritualized therapeutic treatment of psychiatric conditions supplementing the professional psychiatric care available to the population. The variety of forms of the Brazilian psychotherapy stretches from the pre-scientifical methods of the Indian medicine man through the seemingly medieval forms of exorcisme and spiritualism right to the scientifically founded psychotherapy in all its lines. Integrative endeavours towards a culture-anthropological psychotherapy are becoming evident.

Adolescent↗