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Biomedical subjects

P Koch

Publications and source records attributed to P Koch.

At least 109 records · Page 6Linked to original sources
PubMed1995

Allergic contact dermatitis from purified eosin.

We report on a patient, seen in 1993, who developed sensitization to eosin from topical preparations. The patient had a positive patch test reaction to pure tetrabromofluorescein but not to its impurities separated by thin-layer chromatography. Our findings suggest that the allergen was eosin itself.

Aged↗
PubMed1995

Oral lichenoid lesions, mercury hypersensitivity and combined hypersensitivity to mercury and other metals: histologically-proven reproduction of the reaction by patch testing with metal salts.

We report 11 patients seen between 1991 and 1994 with oral lichenoid lesions (OLL). In 10 cases, there was contact with dental amalgam fillings, and in patient no. 10 with both amalgam restorations and a gold crown. The last patient had, in addition to her OLL, lichen planus of the skin and genital mucosa. In 5 cases, combined sensitization to mercury and other metal salts, particularly gold sodium thiosulfate (GST) and palladium chloride (PDC), was observed. In 10 patients, the lesions considerably improved or totally cleared within 1 to 9 months of replacement of restoration materials. Histological examination of biopsies from the test sites of amalgam, mercuric chloride, GST and PDC, taken 10 or 17 days after application of patch tests, showed lichenoid changes in 7 patients with at least 1 of the allergens. As at least 2 patients had inflammatory lesions of the oral mucosa related to both amalgam and gold restorations, combined sensitization to inorganic and organic mercury derivatives, GST and, in 1 case, PDC, a "dental restoration metal intolerance syndrome" is proposed.

Adult↗
PubMed1994

Synthesis, radiochemistry and biological evaluation of a new somatostatin analogue (SDZ 219-387) labelled with technetium-99m.

A new derivative of octreotide SDZ 219-387 [PnAO-(D)Phe(1)-octreotide] was synthesized, which binds specifically and with high affinity to somatostatin receptors in vitro (pKi = 9.79 +/- 0.16). This new somatostatin analogue chelates technetium-99m under mild labelling conditions in good yields. The resulting [99mTc]SDZ 219-387 was stable up to 6 h after labelling and could be isolated in a pure radiochemical and chemical form by high-performance liquid chromatographic purification. The intravenous administration of purified [99mTc]SDZ 219-387 revealed that the radioligand was rapidly cleared from circulation, and tumour uptake of 0.38% ID/g was observed at 1.5 h post injection. [99mTc]SDZ 219-387 specifically interacted with somatostatin binding sites on the tumour. However, the radioligand is highly lipophilic and excreted mainly through the hepatobiliary system. As a consequence, [99mTc]SDZ 219-387 exhibits increased background activity and therefore is not appropriate for the in vivo visualization of somatostatin receptor-positive tumours and/or their metastases in the abdomen.

Animals↗
PubMed1994

Erythema-multiforme-like, urticarial papular and plaque eruptions from bufexamac: report of 4 cases.

4 patients developed an erythema-multiforme-like reaction following acute contact dermatitis from 2 different bufexamac-containing topical preparations. Histologically, the lesions did not show changes that were typical of erythema multiforme. Patch testing gave positive reactions to bufexamac at 1, 2, 3 and 4 days. The histological picture of 2 positive test reactions was suggestive of a drug reaction in the 1st, and of an acute eczematous reaction in the 2nd, case. A systemic allergic reaction with spread of lesions could have been involved, following percutaneous absorption of the allergen.

Adult↗
PubMed1994

Dexa-BEAM in patients with Hodgkin's disease refractory to multidrug chemotherapy regimens: a trial of the German Hodgkin's Disease Study Group.

PURPOSE: A prospective phase II study was conducted to evaluate the efficacy of dexamethasone, carmustine, etoposide, cytarabine, and melphalan (Dexa-BEAM) as salvage chemotherapy for patients with Hodgkin's disease. PATIENTS AND METHODS: Fifty-five patients progressing on or relapsing after eight- or 10-drug chemotherapy (cyclophosphamide, vincristine, procarbazine, and prednisone plus doxorubicin, bleomycin, vinblastine, and dacarbazine [COPP+ABVD] or COPP+ABV+ifosfamide, methotrexate, etoposide, and prednisone [IMEP]) were treated with Dexa-BEAM. Patients who responded after two cycles of Dexa-BEAM either continued treatment for another two to three cycles or received high-dose chemotherapy/autologous bone marrow transplantation (HDCT/ABMT) with cyclophosphamide, etoposide, and carmustine (BCNU) (CVB) as conditioning regimen. RESULTS: Seventeen patients (31%) achieved a complete remission and 16 (29%) a partial remission, resulting in a response rate of 60% (95% confidence interval, 46% to 73%). Progressive disease developed in 18 patients. Toxicity of Dexa-BEAM was acceptable with pronounced, but temporary World Health Organization (WHO) grade III/IV granulocytopenia and thrombocytopenia occurring in more than 90% of all courses. Two patients died of sepsis during granulocytopenia. Three prognostic subgroups could be distinguished: (1) patients progressing on initial chemotherapy, (2) patients relapsing within 12 months, and (3) patients with late relapses. The response rates for these groups were 52%, 60%, and 83%, and the median survival duration 12, 29, and 40+ months, respectively. In a nonrandomized comparison, the survival of patients who responded to two cycles of Dexa-BEAM and had additional cycles of Dexa-BEAM (n = 14) was not different from those responding patients who underwent HDCT/ABMT (n = 19). However, the power to detect a 20% survival difference was only 33% in this comparison. CONCLUSION: Dexa-BEAM is an effective salvage treatment for patients with Hodgkin's disease who fail to respond to multidrug chemotherapy. Efficacy and toxicity are comparable to HDCT/ABMT and underline the need for prospective randomized trials to define better the role of HDCT with and without ABMT in these patients.

Adult↗
PubMed1993

Uncertainties in pharmacokinetic modeling for perchloroethylene: II. Comparison of model predictions with data for a variety of different parameters.

In this paper we compare expectations derived from 10 different human physiologically based pharmacokinetic models for perchloroethylene with data on absorption via inhalation, and concentrations in alveolar air and venous blood. Our most interesting finding is that essentially all of the models show a time pattern of departures of predictions of air and blood levels relative to experimental data that might be corrected by more sophisticated model structures incorporating either (a) heterogeneity of the fat compartment (with respect to either perfusion or partition coefficients or both) or (b) intertissue diffusion of perchloroethylene between the fat and muscle/VRG groups. Similar types of corrections have recently been proposed to reduce analogous anomalies in the fits of pharmacokinetic models to the data for several volatile anesthetics. A second finding is that models incorporating resting values for alveolar ventilation in the region of 5.4 L/min seemed to be most compatible with the most reliable set of perchloroethylene uptake data.

Biological Transport, Active↗
PubMed1993

Use of cytosine arabinoside and total body irradiation as conditioning for allogeneic marrow transplantation in patients with acute lymphoblastic leukemia: a multicenter survey.

We report the experience of 14 centers which have used the combination of cytosine arabinoside (ara-C; 24-36 g/m2) and total body irradiation (TBI) to prepare 213 patients with acute lymphoblastic leukemia (ALL) for allogeneic BMT. The overall 3-year disease-free survival (DFS) probability is 38% (95% CI: 31-45%); 75 patients died of complications and 51 relapsed. Multivariate analysis identified three factors independently associated with outcome: age, remission/relapse status and patient-donor relationship. The 3-year DFS probability is 52% (41-63%) for the 106 patients aged 0-11 and 25% (16-33%) for the 104 aged 11+ years; the DFS probability was 54% (34-74%), 41% (32-49%) and 19% (5-33%) for those in first remission, later remissions and relapse respectively. Older patients suffered both more toxic deaths and more relapses than young ones. No other covariate was found to predict for outcome. The results using ara-C-TBI are similar to those achieved using cyclophosphamide plus TBI to prepare ALL patients for BMT, perhaps because a seemingly lower relapse rate is offset by more toxic deaths particularly in older patients. Therapeutic trials should focus on reducing toxicity while maximizing antileukemic efficacy, and should stratify for patient and disease-related factors.

Adolescent↗
PubMed1992

[Cardiac interactions between ketanserin and the calcium antagonist nifedipine].

Ketanserin and calcium antagonists are frequently used for the treatment of arterial hypertension in the elderly. The possibility that combined treatment with ketanserin and the calcium antagonist nifedipine have a pro-arrhythmic effect was investigated in 20 normal volunteers aged > 60 years with normal or slightly elevated blood pressure. Each subject received monotherapy with ketanserin or nifedipine for 1 week and the combined treatment during the following week. Clinical and biochemical parameters, ECG and 24-hour ECG recording were monitored before and at the end of the first and second treatment weeks. Ketanserin and nifedipine given in monotherapy or in combination did not modify, on average, blood pressure, heart rate, the biochemical variables and the QT interval. In the 24-hour ECG recordings, 2 normal subjects developed a marked increase in the frequency of ventricular ectopics, couplets and ventricular tachycardia after combined treatment. Therefore, the present investigation does not exclude the possibility that combined treatment with ketanserin and nifedipine could increase the prevalence of arrhythmia in some elderly patients.

Aged↗
PubMed1992

A new case of Zimmermann-Laband syndrome with atypical retinitis pigmentosa.

This paper reports a case study of a 10-year-old girl exhibiting symptoms of a Zimmermann-Laband syndrome (ZLS), including an ocular involvement not previously observed. In addition to the case reported, we have also discovered 21 patients described in the literature. Major clinical findings, defined as being present in more than 75% of the cases under discussion, are presented.

Child↗
PubMed1991

alpha Interferon maintenance therapy in patients with low-grade non-Hodgkin's lymphomas after cytoreductive chemotherapy with prednimustine and mitoxantrone.

A combination of prednimustine 100 mg/m2/day orally, days 1-5, and mitoxantrone 8 mg/m2/day intravenously, days 1 and 2, was administered to 19 patients with advanced low-grade non-Hodgkin's lymphoma after failure on or relapse after standard chemotherapy. The prednimustine and mitoxantrone (PmM) regimen was repeated every 4-6 weeks to a maximum of six cycles. Thirteen patients, achieving a complete (4) or partial (9) remission (CR or PR), received two additional courses for consolidation followed by interferon alfa-2b 5 million units (MU) subcutaneously (s.c.) three times weekly until progression or relapse. At the present time, remission duration ranges from 4.5+ to 17.5+ months, with a median of 14.5 months. In a historical comparison to unmaintained first remission preceding the PmM/interferon trial, a tendency towards a longer period of freedom from progression was apparent in the 13 patients receiving interferon maintenance treatment during their second PR or CR. These data provided the basis for a currently ongoing multicentre study randomly comparing initial chemotherapy with PmM versus cyclophosphamide/vincristine (Oncovin)/prednisone (COP) in patients with advanced centroblastic-centrocytic and centrocytic non-Hodgkin's lymphomas, followed by a second randomization in CR and PR patients for maintenance with alpha interferon versus observation only.

Adult↗