Biomedical subjects
Publications and source records attributed to C Kirsch.
The authors have developed a group therapy model specifically for children who are difficult to treat using traditional psychotherapeutic techniques. In the present article they describe this model, which has been employed successfully for the past four years in an elementary school in an area of high social deprivation, in collaboration with teaching staff and a social worker.
Signalling via seven transmembrane helix receptors can lead to a massive increase in cellular PtdIns(3,4,5)P3, which is critical for the induction of various cell responses and is likely to be produced by a trimeric G-protein-sensitive phosphoinositide 3-kinase (PI3Kgamma). We show here that PI3Kgamma is a bifunctional lipid kinase and protein kinase, and that both activities are inhibited by wortmannin at concentrations equal to those affecting the p85/p110alpha heterodimeric PI3K (IC50 approx. 2 nM). The binding of wortmannin to PI3Kgamma, as detected by anti-wortmannin antisera, closely followed the inhibition of the kinase activities. Truncation of more than the 98 N-terminal amino acid residues from PI3Kgamma produced proteins that were inactive in wortmannin binding and kinase assays. This suggests that regions apart from the core catalytic domain are important in catalysis and inhibitor interaction. The covalent reaction of wortmannin with PI3Kgamma was prevented by preincubation with phosphoinositides, ATP and its analogues adenine and 5'-(4-fluorosulphonylbenzoyl)adenine. Proteolytic analysis of wortmannin-prelabelled PI3Kgamma revealed candidate wortmannin-binding peptides around Lys-799. Replacement of Lys-799 by Arg through site-directed mutagenesis aborted the covalent reaction with wortmannin and the lipid kinase and protein kinase activities completely. The above illustrates that Lys-799 is crucial to the phosphate transfer reaction and wortmannin reactivity. Parallel inhibition of the PI3Kgamma-associated protein kinase and lipid kinase by wortmannin and by the Lys-799-->Arg mutation reveals that both activities are inherent in the PI3Kgamma polypeptide.
Parsley (Petroselinum crispum) plants and suspension-cultured cells have been used extensively for studies of non-host-resistance mechanisms in plant/pathogen interactions. We now show that treatment of cultured parsley cells with a defined peptide elicitor of fungal origin causes rapid and large changes in the levels of various unsaturated fatty acids. While linoleic acid decreased and linolenic acid increased steadily for several hours, comparatively sharp increases in oleic acid followed a biphasic time course. In contrast, the overall level of stearic acid remained unaffected. Using a PCR-based approach, a parsley cDNA was isolated sharing high sequence similarity with omega-3 fatty acid desaturases. Subsequent isolation and characterization of a full-length cDNA enabled its functional identification as a plastid-localized omega-3 fatty acid desaturase by complementation of the Arabidopsis thaliana fad7/8 double mutant which is low in trienoic fatty acids. omega-3 Fatty acid desaturase mRNA accumulated rapidly and transiently in elicitor-treated cultured parsley cells, protoplasts, and leaves, as well as highly localized around fungal infection sites in parsley leaf buds. These results indicate that unsaturated fatty acid metabolism is yet another component of the highly complex, transcriptionally regulated pathogen defense response in plants.
Treatment of cultured parsley (Petroselinum crispum L.) cells with a structurally defined peptide elicitor (Pep25) of fungal origin has previously been shown to cause rapid and large changes in the levels of various desaturated fatty acids. We isolated two distinct parsley cDNAs sharing high sequence similarity with microsomal omega-6 fatty acid desaturases (FADs). One of them was functionally identified as a delta 12 FAD by expression in the yeast Saccharomyces cerevisiae. Two dienoic fatty acids, hexadecadienoic and linoleic, which were not detectable in control cells, together constituted up to 12% of the total fatty acids in the transformed yeast cells. delta 12 FAD mRNA accumulated rapidly and transiently in elicitor-treated parsley cells, protoplasts, and leaves. These and previous results indicate that fatty acid desaturation is an important early component of the complex defense response of parsley to attempted fungal infection.
Treatment of cultured parsley cells (Petroselinum crispum) with fungal elicitor caused large increases in the activities of chitinase and 1,3-beta-glucanase. Chitinase activity accumulated predominantly in the culture medium, whereas 1,3-beta-glucanase activity was located almost exclusively intracellularly. Extracellular chitinase activity was resolved into six different isoenzymes, all of which were purified and characterized. All six isoforms were acidic proteins (pI 3.8-5.3), with molecular mass 30-38 kDa. Four were exochitinases and two were endochitinases. The most abundant isoform also showed lysozyme activity. Three of the exochitinases were glycoproteins and two of these were reactive with an antiserum specific for xylose in complex glycosidic structures. The exochitinases constituted relatively small proportions of the total chitinase activity and may serve a different function in cellular metabolism compared to the more abundant endochitinases.
The spontaneous course of 58 patients with compensated autonomous adenoma of the thyroid was followed. Scintigraphic appearance (compensated (CAA) or decompensated (DAA)) was documented and the serum levels of thyroxine (T4), triiodothyronine (T3) and thyroid-stimulating hormone after TSH-stimulating hormone were measured at the beginning of observation and 3.8 years (median) later. During follow-up period, 13 patients (22%) with CAA developed DAA. 9/13 patients (15%) had overt hyperthyroidism with elevated T4 and/or T3 levels, 4/13 patients (7%) had normal thyroid hormone levels. Life table analysis showed a risk for developing hyperthyroidism of 19% at five years. The size of all adenomata measured scintigraphically was increasing during follow-up, and there was no discrimination of CAA from DAA using this technique. Eight CAA patients received iodinated contrast medium but none develop DAA. In conclusion from these results as well as from the literature, there is no indication for surgery or radioiodine therapy of patients with a CAA, even if there are plans to administer iodinated contrast medium.
Sixty-six tension headache patients were randomly assigned to one of four conditions for 8 weeks: (a) progressive muscle relaxation (PMR) alone; (b) PMR plus cognitive therapy (PMR + Cog); (c) pseudomeditation, a credible attention-placebo control; or (d) continued headache monitoring. A comparison of overall headache activity (headache index), derived from a daily headache diary, for 4 weeks before treatment to 4 weeks after treatment, revealed that active treatment (PMR and PMR + Cog) was superior to either control condition. Moreover, level of headache medication consumption decreased significantly for the active treatment groups. Although headache-index comparisons of the two active treatments showed no advantage for adding cognitive therapy to PMR, a measure of clinically significant change showed a trend for PMR + Cog to be superior to PMR alone.
One-hundred-sixteen patients suffering from vascular headache (migraine or combined migraine and tension) were, after 4 weeks of pretreatment baseline headache monitoring, randomly assigned to one of four conditions: (a) thermal biofeedback with adjunctive relaxation training (TBF); (b) TBF plus cognitive therapy; (c) pseudomediation as an ostensible attention-placebo control; or (d) headache monitoring. The first three groups received 16 individual sessions over 8 weeks, while the fourth group continued to monitor headaches. All groups then monitored headaches for a 4-week posttreatment baseline. Analyses revealed that all treated groups improved significantly more than the headache monitoring group with no significant differences among the three treated groups. On a measure of clinically significant improvement, the two TBF groups had slightly higher (51%) degree of improvement than the meditation group (37.5%). It is argued that the attention-placebo control became an active relaxation condition.
Seventy-six patients with vascular (migraine or mixed migraine and tension) headache (HA) participated in a controlled evaluation of a minimal-therapist-contact, largely home-based, treatment program which combined relaxation (R) training with thermal biofeedback (TBF). One group received TBF + R administered in 3 office visit over 8 weeks, supplemented by audio tapes and manuals. A second group received the TBF + R plus instruction in cognitive stress coping techniques, all of which was administered in 5 office visits over 8 weeks. A third group monitored headache activity for 8 weeks. Evaluations, based on 4 weeks of HA diary at pre-treatment and after treatment, revealed significantly greater reductions in HA activity and medication consumption for both treated groups than the HA monitoring controls who did not change. Significantly more of the treated patients had clinically significant reductions in HA activity than the controls. The two treated groups did not differ on any measure.