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P Koch

Publications and source records attributed to P Koch.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Peri-articular ossification in total hip prostheses].

The frequency and predisposing factors of ectopic bone formation (EBF) after total hip arthroplasty (THA) are analyzed in 6026 primary THA documented at the M.E. Mueller Foundation in Berne. Series from two clinics [the Lindenhof Clinic in Berne (n = 816) and the Wilhelm Schulthess Clinic in Zürich (n = 612)] are analyzed separately and the results compared with those in the literature. Overall EBF was found in 38.3% of the patients; in 8.6%, it was clinically obvious (grades III and IV according to the classification of Brooker et al.) and is analyzed in this study. EBF was found in 13.4% of the men compared with 4.2% of the women. The frequency of EBF was found to be particularly low in patients with rheumatoid arthritis (4.4%), and EBF was found in 11.4% of patients with post-traumatic osteoarthritis and in 11.1% with idiopathic necrosis of the femoral head. Severe preoperatively limited hip movement did not significantly increase the risk of EBF (11.9%), nor did previous hip surgery, such as intertrochanteric osteotomy (11.3%). Postoperative hematoma that led to puncture or even evacuation was responsible in 14.4%. The therapeutic and prophylactic possibilities are compared with those in the literature, and our personal observations are discussed.

Arthritis, Rheumatoid↗
PubMed1989

Cybernetic model of psychophysiological pathways: I. Control functions.

Electrophysiological events carry information, but the signals are not specific for a given bit of information. Therefore, the nervous system is required to extract the information from a multitude of signals. The process of information recognition is achieved by a superization process, i.e., by means of transition from many lower-order signals to a superior-order signal. In this way, a gradual recognition of the respective signal's emitting sources is realized. The recognition is performed with the aid of certain logical circuits representing models of different sources written in the structure of the neuronal network. In this manner, the nervous system passes step by step from control by means of signals to control by means of information. The superior structures can thereby exert much more subtle control and supervise the inferior structures that work by signals. However, because this control cannot refine all the general information of the inferior structures, psychophysiological dysfunction may occur. The nature of the superization process from signals to information is examined in this paper.

Cybernetics↗
PubMed1989

The sleep/wake cycle in 4- to 14-month old children: general aspects and sex differences.

The sleep/wake cycle of 39 children, 4 to 14 months of age was observed and recorded continuously (24 h per day) over a 4-month period, one full week per month, from November 1986 through February 1987. Total sleep time per day was analyzed for the different age groups and for the two sexes. A decrease in total sleep time is shown as a function of increasing age for the whole population. Analyzing boys and girls separately, a differential effect on total sleep time was demonstrated, girls tending to sleep more after 10 months of age.

Age Factors↗
PubMed1988

Different effects of R 56865 and calcium entry blockers on K+- and noradrenaline-induced contractions and 45Ca uptake in rat aorta.

The effects of R 56865, nifedipine, verapamil, diltiazem and flunarizine on K+- and NA-induced contractions and K+-induced 45Ca uptake were compared in the isolated rat aorta. The calcium entry blockers concentration dependently inhibited the K+-induced contraction and 45Ca uptake over the same dose-range. R 56865 inhibited the K+-induced 45Ca uptake, but only partly inhibited the K+-induced contraction. The calcium entry blockers caused a slight rightward shift and a depression of the maximum of the concentration-response curve for the NA-induced contraction. In contrast, R 56865 caused a strong, dose-dependent rightward shift and a depression of the maximum, 10(-6) and 10(-5) M being equieffective. The effects of R 56865 and nifedipine were independent of each other. Nevertheless, the NA-induced increase in 45 Ca uptake, a putative model for Ca influx, was attenuated by R 56865. In conclusion, R 56865 is a weak inhibitor of the K+-induced Ca influx but is without effect on the NA-induced Ca influx. The discrepancy between its effects on K+-induced contractions and 45Ca uptake may be explained by an inhibition of the uptake of 45Ca from the cytosol into the 45Ca pool. The interaction between R 56865 and the alpha 1-adrenoceptor-mediated contractions may be explained by an action at a site that is distinct from the NA-binding-site on the alpha 1-adrenoceptor.

Animals↗
PubMed1988

Distinction between HIV-1 and HIV-2 infection using novel synthetic lipopeptide conjugates as antigens in enzyme immunoassays.

A novel immunoassay technique using synthetic lipopeptide (Pam3Cys-Ser) linked to immunodominant peptide domains of HIV-1 and HIV-2 envelope proteins as an antigen adsorbent has been developed. Attachment of peptides to microtiter plates can be considerably improved with this method by employing the hydrophobic properties of lipopeptide. From the sera of 121 HIV-1 infected patients 117 reacted with Pam3Cys-Ser-[HIV-1(598-609)cyclic disulfide]. Five of 5 HIV-2 positive sera were positive with Pam3Cys-Ser-[HIV-2(593-603)cyclic disulfide]. Control sera failed to react with these conjugates.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Ectopic ossification following total hip arthroplasty: is diffuse idiopathic skeletal hyperostosis a risk factor?

Total hip arthroplasty may be followed by ectopic bone formation. An increased frequency has been suspected in patients with diffuse idiopathic skeletal hyperostosis (DISH). In 204 patients we found that, of the 38 subjects with pre-existing DISH, 29% developed postoperative ossification compared with only 10% in those without DISH (p less than 0.01). DISH is therefore a risk factor for postoperative ectopic bone formation. In a separate study of 1325 patients (not analysed for spinal DISH), we looked for correlations between the severity of postoperative ectopic bone and clinical measurements. Even for the more severe ossification grades (n = 112), only 10% reported serious pain and only 26% had reduced hip flexion (less than 70 degrees). Thus, periprosthetic ectopic bone is not sufficiently important to justify the routine use of preventative drugs such as bisphosphonates in patients with DISH undergoing total hip replacement.

Adult↗
PubMed1988

Behavioural and cardiovascular changes in children moving from kindergarten to primary school.

The effect of changing school environment from kindergarten to primary school and of the degree of structure of school tasks was examined in relation to behavioural and cardiovascular (heart rate, systolic and diastolic blood pressure) patterns. Changing school environment was associated with an increase in the duration of stereotyped behaviours. The accompanying psychophysiological variables, which in kindergarten follow the simple motor activity/arousal model, are reversed in primary school where less motor activity is accompanied by higher states of physiological arousal. The results suggest that children develop cardiovascular responses as part of an adjustment to cope with changes in the environment.

Arousal↗
PubMed1988

[Intensive combined therapy for high-risk ALL patients].

In the risk-adapted multicenter trial (02/84) for adult ALL the effectiveness of a consolidation therapy consisting of VM26 and Ara-C for high-risk patients was tested. Out of a total of 442 patients in the study, 79.2% achieved a complete remission. For the 182 high-risk patients the median remission duration is 17 months and the probability of being in continuous complete remission (CCR) is 34%. Improved results were found for elderly ALL patients between 35 and 65 years of age, whose median remission duration and CCR rate are 19 months and 40% respectively, compared to 15 months and 26% in the former study 01/81. The consolidation therapy has apparently also benefited patients with the immunological subtype c-ALL, for whom the CCR rate at 3 years is 53% in comparison to the previous value of 34%.

Adolescent↗
PubMed1988

Parasternal mediastinal sonography: sensitivity in the detection of anterior mediastinal and subcarinal tumors.

Twenty-seven patients with anterior mediastinal and subcarinal mediastinal tumors confirmed by CT and 30 control subjects were prospectively investigated by sonography performed via a parasternal approach in both decubitus positions. The sonograms and CT scans were interpreted blindly by two investigators and the results of the two procedures were compared. In the group of 30 controls, sonography via the right parasternal approach showed the anterior mediastinum in 29 (97%) and the subcarinal space in 27 (90%). Fifteen (94%) of 16 anterior mediastinal tumors and 16 (94%) of 17 subcarinal tumors were identified sonographically. These results show that parasternal sonography is a sensitive technique for the detection of tumors in the anterior mediastinal and subcarinal mediastinal spaces.

Adult↗
PubMed1988

Identification of metabolic pathways of pindolol and fluperlapine in adult human hepatocyte cultures.

1. Adult human hepatocytes were obtained from a normal donor and a barbiturate-overdose fatality and maintained either in pure culture or in co-culture with rat liver epithelial cells. At varying times of culture, metabolic pathways of pindolol and fluperlapine, two drugs which are transformed at different rates and routes in man and rat, were determined after a 24 h incubation. 2. In both culture conditions, human hepatocytes remained able to form the major urinary metabolites of pindolol and fluperlapine, including oxidized products, glucuronide and sulphate conjugates over the whole period studied (i.e. 5 and 21 days in pure and co-culture respectively). 3. Fluperlapine which has the higher first pass in man and animals was found to be metabolized in vitro more quickly than pindolol. 4. Some qualitative and quantitative differences were found between normal and drug-altered human hepatocytes, indicating that in vivo environmental factors may greatly influence metabolic properties of these cells even after several days in culture.

Animals↗
PubMed1988

Intravenous immunoglobulin may lessen all forms of infection in patients receiving allogeneic bone marrow transplantation for acute lymphoblastic leukemia: a pediatric oncology group study.

Fifty patients with refractory acute lymphoblastic leukemia underwent allogeneic bone marrow transplantation after conditioning with high-dose cytosine arabinoside and fractionated total body irradiation. Twenty-nine received intravenous immunoglobulin (i.v.Ig) infusion, primarily to prevent cytomegalovirus infection, and 21 did not. The two groups were biologically comparable. Seven (24.5%) of the i.v.Ig-treated and 14 (66.7%) of the non-i.v.Ig-treated patients developed systemic viral, fungal or bacterial infections and/or interstitial pneumonitis (p less than 0.005), which were fatal in three and 12 cases respectively (p less than 0.001). Currently, 23 (79.3%) of the 29 i.v.Ig-treated and eight (38.1%) of the 21 non-i.v.Ig-treated patients are alive and well (p less than 0.01). We conclude that prophylactic i.v.Ig infusions may reduce the frequency of all forms of serious infection in patients with acute lymphoblastic leukemia undergoing allogeneic marrow transplantation, and thereby improve their survival expectation.

Bone Marrow Transplantation↗
PubMed1988

[Relationship between general motor activity of children at school and the duration of school tasks].

A behavioural study was carried out with 20 children aged from 6 to 7 years attending the first year of primary school from 9:00 to 10:00 A.M. and 2:00 to 3:00 P.M. It appeared that the frequency and duration of getting up and moving around increased from the beginning to the end of both time intervals. There are significant positive correlations between these parameters and the duration of school tasks. It can be suggested that the general activity level is increased as a consequence of restraining children's general body activity and/or imposing on them sustained mental investment in school tasks.

Child↗
PubMed1988

Prognostic factors in a multicenter study for treatment of acute lymphoblastic leukemia in adults.

In a prospective multicenter study, 368 acute lymphoblastic leukemia (ALL) patients aged 15 to 65 years were treated with an intensified induction and reinduction regimen; 272 (73.9%) achieved complete remission (CR). The median remission duration (MRD) is 24.3 months, and the probability of being in continuous CR (CCR) at greater than 5 years is .37. The median survival for all 368 patients is 27.5 months, and the probability of being alive at 5 years is .39. For the 272 patients in remission the median survival is 58.4 months, and the probability of being alive at 5 years is .49. A lower CR rate was seen for patients with bleeding at diagnosis or with splenomegaly/hepatosplenomegaly. The prognostic factors unfavorable for remission duration were time to CR greater than 4 weeks v less than 4 weeks (P = .0002), age greater than 35 years v less than 35 years (P = .0008), leukocyte count greater than 30,000/microL v less than 30,000/microL (P = .0112), and null ALL v common ALL (c-ALL)/T cell ALL (T-ALL) (P = .05). The remission duration correlated strongly (P = .0001) with the number of these independent prognostic factors. In patients with none of these adverse factors the MRD has not yet been reached, with one adverse factor the MRD is 21.9 months, and with two or three adverse factors the MRD is only 9.6 months. For the immunologic subtype T-ALL, the probability of being in CCR at greater than 5 years is .55; for c-ALL, .34; and for null ALL, .24. According to these results, patients were stratified into a low-risk group with a CCR rate of .62 and a high-risk group with a CCR rate of .28, with the latter now allocated to either further chemotherapy or bone marrow transplantation in first remission.

Adolescent↗
PubMed1987

Neuraminidase-treated allogeneic blasts for maintenance in acute myelogenous leukemia: results of a prospective randomized trial.

Between July 1, 1981, and July 1, 1985, 167 patients with acute myelogeneous leukemia (AML) were treated with one or, if necessary, two courses of a modified TAD regimen (TAD9) for induction. 96 patients (58%) achieved a complete remission (CR); 62 achieved CR after one and 34 patients after two courses of TAD9. 29 patients (17%) were considered early deaths, and 42 patients (25%) nonresponders. For CR maintenance 64 patients were eligible according to protocol criteria; 33 patients were randomized to chemotherapy, only, (CT) by monthly courses of cytosine arabinoside (ARA-C) alternatingly combined with daunorubicin or thioguanine or cyclophosphamide, while 31 patients were randomized to receive immunotherapy in addition to chemotherapy (CIT) by intradermal injections of 10(10) neuraminidase-treated viable allogeneic blasts per immunization interspersed between the CT courses. Maintenance therapy was given for up to 3 years. The median survival in CT patients is 23 months, while in CIT patients the median has not been reached after 54 months; corresponding median relapse-free survival is 15 months for the CT patients as opposed to 40 months for the CIT group. The differences are not significant. Comparing CT with CIT, the survival data show a persistent trend in favor of CIT; under the conditions of the study, however, a substantial benefit of immunotherapy may be restricted to a certain subset of patients with low risk for early relapse.

Antineoplastic Combined Chemotherapy Protocols↗