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K Simon

Publications and source records attributed to K Simon.

At least 19 recordsLinked to original sources
PubMed2000

[Principles of evidence-based medicine; merits and pitfalls].

Historical background, main principles, methodology of evidence based medicine (EBM) and prospective randomized trials (incl. megatrials) are reviewed. EBM has a significant beneficial influence on medical activities as follows: improving efficacy of medical therapy, generation of new research trends, optimizing decision making in clinical settings of incomplete pathophysiological background, exploring new associations can be found beyond the individual clinician's scope, regular financial support of gradual, postgradual medical training, medical research and international scientific programs. Potential adverse influences related to EBM are: weakening position of individual (versus modus) patient-oriented approach in medical care, diminution of pathophysiology- (versus product-) oriented medical research, reevaluation of medical, scientific activity, interrelations between medical doctors and patients. Potential misuse of statistical methods in evaluation of megatrials is briefly discussed. A combination of benefits related to EBM and traditional elements of classical medical care, clinical research is needed to establish a more improved medical care for the individual patient.

Animals↗
PubMed2000

Phase I clinical and pharmacokinetic study of perillyl alcohol administered four times a day.

We conducted a phase I dose-escalation trial of perillyl alcohol (POH; NSC 641066) given p.o. on a continuous four times a day basis to characterize the maximum tolerated dose, toxicities, pharmacokinetic profile, and antitumor activity. Sixteen evaluable patients with advanced refractory malignancies were treated at the following doses: level 1 (L1), 800 mg/m2/dose; L2, 1200 mg/m2/dose; L3, 1600 mg/m2/dose. POH was formulated in soft gelatin capsules containing 250 mg of POH and 250 mg of soybean oil. The predominant toxicities seen were gastrointestinal (nausea, vomiting, satiety, and eructation), which were dose limiting. There appeared to be a dose-dependent increase in levels of the two main metabolites, perillic acid and dihydroperillic acid. No significant differences were seen whether the drug was taken with or without food. There was a trend toward decreasing metabolite levels on day 29 compared with days 1 and 2. Peak metabolite levels were seen 1-3 h post ingestion. Metabolite half-lives were approximately 2 h. Approximately 9% of the total dose was recovered in the urine in the first 24 h, the majority as perillic acid. Evidence of antitumor activity was seen in a patient with metastatic colorectal cancer who has an ongoing near-complete response of > 2 years duration. Several other patients were on study for > or = 6 months with stable disease. The maximum tolerated dose of POH given continuously four times a day was 1200 mg/m2/dose. Gastrointestinal toxicity was dose limiting, although significant interpatient variability in drug tolerance was seen.

Administration, Oral↗
PubMed1999

[Two cases of malignant and benign systemic mastocytosis].

The authors give a short account about the clinical histories of two patients: one with malignant systemic mastocytosis resulting in acute myeloid leukaemia, the other with indolent systemic mastocytosis. A brief review is reported about the physiological and pathophysiological role of mastocyte system. Benign and malignant types, classification of mastocyte proliferation are detailed, several distinct characteristics of clinical appearance, main aspects of diagnosis, therapy and prognosis in patients with different forms of systemic mastocytosis are briefly discussed.

Adult↗
PubMed1999

Intraarticular fentanyl compared with morphine for pain relief following arthroscopic knee surgery.

PURPOSE: To compare the analgesia produced by comparable doses of intra-articular (IA) morphine and fentanyl. METHODS: Sixty-nine healthy patients undergoing arthroscopic surgery received a standardized general anesthetic of 4 mg x kg(-1) thiopental and 2 microg x kg(-1) fentanyl followed by 2 mg x kg(-1) succinylcholine prior to tracheal intubation and controlled ventilation. Maintenance of anesthesia was achieved with N2O/O2 and isoflurane. At the conclusion of surgery intra-articular injection was: Group I (n=23) 50 microg fentanyl in 20 ml saline; Group II (n=24) 3 mg morphine in 20 ml saline; Group III (n=22) 20 ml saline. Pain scores at rest using a visual analogue scale were recorded by a separate blinded observer at one, two, four, and eight hours postoperatively. RESULTS: Pain scores at one, two, four, and eight hours were 36, 26.3, 20.9, and 12.8 vs 35.8, 33.8, 28.8, and 21.9 vs 70.5, 57.7, 58.4, and 53.6 for the IA-fentanyl, IA-morphine, and control groups respectively. Pain scores were greater at all times for Group III. Pain scores for Groups I and II were similar at one hour, but thereafter were less (P < 0.001) for the IA-fentanyl group. CONCLUSION: Better postoperative analgesia was achieved with 50 microg intraarticular fentanyl than with 3 mg intraarticular morphine.

Adolescent↗
PubMed1999

A pilot study of melphalan, tumor necrosis factor-alpha and 41.8 degrees C whole-body hyperthermia.

PURPOSE: To evaluate the feasibilitv of sequencing (based on preclinical modeling) tumor necrosis factor-a (TNF) at two dose levels with melphalan (L-PAM) and 41.8 C whole-body hyperthermia (WBH) for 60 min. PATIENTS AND METHODS: Nine patients with refractory cancer were treated from October 1995 to June 1997. The study encompassed a total of 20 trimodality treatment courses. Three patients were treated at TNF dose level I (50 microg/m2) and six patients were treated at TNF dose level II (100 microg/m2). TNF was delivered as a 24-h intravenous infusion, 48 h prior to the combination of L-PAM and WBH; L-PAM was given over 10 min at target temperature at a dose of 17.5 mg/ m2 based on a previous phase I WBH/L-PAM trial. WBH was administered with an Aquatherm radiant heat device. RESULTS: Myelosuppression was the major toxicity associated with therapy, but there were no instances of bleeding or neutropenic fevers. Grade 3 thrombocytopenia was seen with 15% of treatments. Regarding absolute neutrophil count, 15% of treatments were associated with grade 3 toxicity, and 45% with grade 4 toxicity, and regarding white blood cell count, 50% of treatments were associated with grade 3 toxicity and 10% with grade 4 toxicity. The myelosuppression observed was equivalent to that seen in our earlier phase I study of WBH and L-PAM (without TNF). Only mild toxicities (grade 1 or 2) were associated with TNF; these were seen with <25% of treatments and included nausea, vomiting, diarrhea, fevers, and headache. There were no instances of hypotension. There was no relationship between toxicities observed and the two TNF dose levels. Mild WBH toxicities were seen with less than 15% of treatments; these included nausea, vomiting, and herpes simplex I. Responses included two complete remissions (malignant melanoma, TNF dose level I; breast cancer, TNF dose level II), and two disease stabilizations (both malignant melanoma, TNF dose level I). CONCLUSION: We conclude that the combination of TNF, L-PAM, and WBH is well tolerated at the dose levels studied. The clinical results justify further clinical investigation for this trimodality treatment approach.

Adult↗
PubMed1999

Isolation and identification by partial sequencing of the 18S ribosomal gene of free-living amoebae from necrotic tissue of Basilliscus plumifrons (Sauria: Iguanidae).

A 3-year-old Basiliscus plumifrons developed a necrotic lesion on the tail resulting from nodules of unknown etiology. Investigation of necrotic tissue revealed several gram-negative bacteria as well as three different species of free-living amoebae. The amoebae were identified by morphological characters as belonging to the genera Acanthamoeba, Echinamoeba, and Naegleria, respectively. Partial sequencing of the 18S ribosomal gene was performed for reliable systematic determination. Two of the isolates showed thermotolerance. No isolate was growable in conventional liquid media, but the Acanthamoeba strain readily grew on a human cell line (HEp2). It remains unclear whether the amoebae fed on the coexisting bacteria or on host tissue.

Acanthamoeba↗
PubMed1999

Current knowledge in the management of children and adolescents with sickle cell disease: Part 1, Physiological issues.

This article reviews the current state of the knowledge in the management of children and adolescents with sickle cell disease (SCD). A thorough review of the literature concerning physiological issues including the clinical manifestations of SCD as well as current treatment modalities is included. Therapeutic management of health and illness for a child with SCD is discussed in relation to primary, secondary, and tertiary prevention. Recommendations for nursing practice and research are made.

Adolescent↗
PubMed1999

Child drawing: hospital--an instrument designed to measure the emotional status of hospitalized school-aged children.

Hospitalization has long been accepted as a stressful experience for children, but the degree of anxiety experienced by any child is unknown. Physiological status is routinely measured, but the same is not true for emotional status. "The Child Drawing: Hospital" was developed as a means of measuring the emotional status of the hospitalized school-aged child. This report presents the validity and reliability of the "Child Drawing: Hospital" as a measure of anxiety for hospitalized children.

Anxiety↗
PubMed1999

Seroprevalence of Bartonella henselae in cats in Germany.

Bartonella henselae and B. quintana infections in man are associated with various clinical manifestations including cat-scratch disease, bacillary angiomatosis and bacteraemia. While cats are the natural reservoir for B. henselae, the source of B. quintana is unclear. In this study, the sera of 713 cats from Germany were examined for the presence of antibodies against B. henselae, B. quintana or Afipia felis by an indirect immunofluorescence assay (IFA). Bartonella-specific antibody titres of > or =50 were found in 15.0% of the cats. There was substantial cross-reactivity among the various Bartonella antigens, although single sera showed high titres against B. henselae but not against B. quintana and vice versa. Antibodies against A. felis were not detected in any of these cats. Statistical analysis indicated that there is no correlation between Bartonella infections and the sex, age or breed of the cat or its hunting behavior. There was also no correlation between bartonella and toxoplasma infections in cats. However, whereas 16.8% of cats from northern Germany had B. quintana-specific antibodies, only 8.0% of cats from southern Germany were seropositive for B. quintana. No statistically significant difference was found for B. henselae. IFA-positive and IFA-negative sera were used for immunoblot analysis including B. henselae and B. quintana. Marked reactivity was observed with protein bands at 80, 76, 73, 65, 37, 33 and 15 kDa. The results of this study suggest that B. henselae, and possibly a B. quintana-related pathogen, but not A. felis, are common in cats in Germany, and that there are differences in the geographic distribution of bartonella infections in cats.

Animals↗
PubMed1999

[Pseudopolymorphism of NO-SPA, 1-(3,4-diethoxy-benzyl)-6,7-diethoxy-3,4-dihydro-isoquinoli ne hydrochloride].

The spasmolytic agent No-Spa, 1-(3,4-diethoxybenzyl)-6,7-diethoxy-3,4-dihydroisoquinoli ne hydrochloride (1) is a synthetic analogue of the naturally occurring alkaloid papaverine. (1) is prone to form stoichiometric crystalline solvates with a number of solvents causing technological and stability problem. Present paper describes the X-ray structure determination of the hemiethanol, hemibenzene and hemihydrochloride structures being the most important and interesting from both practical and theoretical point of view. The solvate formation is facilitated by the presence of the flexible ethoxy group encapsulating the solvent and by the quasi perpendicular position of the isoquinoline and phenyl group.

Crystallography, X-Ray↗
PubMed1998

[Tumor necrosis factor-alpha; a possible pathogenic factor in obesity in insulin resistant and non-insulin-dependent diabetes mellitus?].

The role of tumor necrosis factor (TNF)-alpha in the development of insulin resistance has repeatedly been emphasized in the past few years. The present paper summarizes the data (including the authors' observations as well) focusing on the potential role of TNF-alpha in the pathogenesis of obesity and non-insulin-dependent diabetes mellitus: alteration of insulin receptor function, lipid metabolism, expression of sulphonylurea receptors, all of them suggested to be related to the TNF-alpha. The potential clinical relevances are shortly reviewed.

Cytokines↗
PubMed1998

Elevated serum tumor necrosis factor-alpha concentrations and bioactivity in Type 2 diabetics and patients with android type obesity.

The role of tumor necrosis factor-alpha in insulin resistance has been studied in 59 patients with Type 2 diabetes, 28 with android type obesity and 35 healthy lean controls. Immunoreactive concentrations and bioactivity of serum tumor necrosis factor-alpha have repeatedly been determined in 8 weeks intervals for 12 months, five times per patients, by using ELISA and L929 cell cytotoxicity bioassay. Significantly higher immunoreactive tumor necrosis factor-alpha concentrations and bioactivity have been found in both, the Type 2 diabetic and obese groups as compared to the healthy persons. Tumor necrosis factor-alpha concentrations and bioactivity have showed a significant positive linear correlation with the elevated basal serum C-peptide levels and body mass indexes in both groups of patients. According to these data the cytokine might play a role in insulin resistance in obesity as well in Type 2 diabetes.

Adipose Tissue↗
PubMed1998

Phase I clinical and pharmacokinetic trial of penclomedine using a novel, two-stage trial design for patients with advanced malignancy.

PURPOSE: A novel phase I trial design was used to determine the maximum-tolerated dose (MTD) and pharmacokinetics for penclomedine when administered as an intravenous (i.v.) infusion over 1 hour daily for 5 days, repeated every 28 days. This study also tests the feasibility of a novel two-stage design for phase I trials. PATIENTS AND METHODS: Twenty-eight patients with advanced malignancy who met standard eligibility criteria were treated with i.v. penclomedine. The initial daily dose was 50 mg/m2. Dose escalations were planned using a modified Fibonacci sequence. One patient was enrolled on each dose level during the first stage of this trial. In the second stage, patients were enrolled in cohorts of three, proceeding in an up-and-down manner based on toxicities observed. MTD was determined by logistic regression analysis. Pharmacokinetic assessment was performed during the first cycle of treatment. RESULTS: Dose-limiting toxicities (DLT) observed during this trial were principally neurologic and were self-limited. Although hematologic toxicity was rare, the few patients with significant hematologic changes experienced late nadirs with prolonged time to recovery. The MTD was estimated as 381 mg/m2 (80% CI, 343 to 415 mg/m2). Although there was a long elimination half-life, accumulation of penclomedine over the 5 days of administration was negligible. CONCLUSION: The novel trial design used in this study was safe and appeared effective in limiting the numbers of patients treated at lower-dose levels. Reversible neurotoxicity was dose-limiting. Although the estimated MTD was 381 mg/m2, any dose within the CI would be reasonable for phase II study.

Adult↗