Search PubMed⌕ Search

Biomedical subjects

D Rauch

Publications and source records attributed to D Rauch.

At least 19 recordsLinked to original sources

A randomized phase II trial of capecitabine and two different schedules of irinotecan in first-line treatment of metastatic colorectal cancer: efficacy, quality-of-life and toxicity.

BACKGROUND: To determine the efficacy, impact on quality-of-life (QoL) and tolerability of two different irinotecan administration schedules in combination with capecitabine as first-line treatment of metastatic colorectal cancer. PATIENTS AND METHODS: We carried out a randomized phase II trial to select one of the following treatment regimens for further investigation: weekly irinotecan at a dose of 70 mg/m(2) days 1, 8, 15, 22, 29 (arm A) or 3-weekly irinotecan at a dose of 300/240 mg/m(2) day 1 and days 22 (arm B) in combination with capecitabine 1000 mg/m(2) twice daily days 1-14 and days 22-35 every 6 weeks. RESULTS: Seventy-five patients with good performance status entered the trial. The two arms were well balanced for relevant patient and disease characteristics. The most frequent toxic effects were grade 3/4 diarrhea (arm A: 34%, B: 19%), grade 3/4 neutropenia (A: 5%, B: 19%) and grade 2/3 alopecia (A: 26%, B: 65%). Other grade 3/4 toxic effects were rare (<5%). Response rates were 34% [95% confidence interval (CI) 20% to 51%] in arm A and 35% (95% CI: 20% to 53%) in arm B. Median time to progression was 6.9 (4.6-10.1) and 9.2 (7.9-11.5) months and median overall survival was 17.4 (12.6-23.0+) and 24.7 (16.3-26.4+) months. Patients with an objective tumor response reported better physical well-being (P < 0.01), mood (P < 0.05), functional performance (P < 0.05) and less effort to cope (P < 0.05) compared with the non-responders and stable disease patients. CONCLUSIONS: The primary end point of this study was the objective response rate and based on the statistical design of the trial, the 3-weekly irinotecan schedule was selected over weekly irinotecan administration. The 3-weekly irinotecan schedule also seemed advantageous in terms of grade 3/4 diarrhea, time to progression, overall survival and patient convenience, but the study was not designed to detect differences in these parameters. In addition, tumor response was shown to have a beneficial effect on QoL indicators.

Adult↗

Capecitabine and vinorelbine in elderly patients (> or =65 years) with metastatic breast cancer: a phase I trial (SAKK 25/99).

BACKGROUND: Few chemotherapy regimens are suitable for the treatment of elderly patients with advanced breast cancer. With the aim of finding a regimen with a low burden of subjective non-overlapping toxic effects, vinorelbine and capecitabine were chosen to be investigated in a phase I dose-finding study. PATIENTS AND METHODS: Thirty-six patients with advanced breast cancer were stratified for the presence of bone and non-bone involvement and treated at four dose levels from capecitabine 800 mg/m2 orally days 1-14 and vinorelbine 20 mg/m2 intravenously days 1 and 8, to capecitabine 1250 mg/m2 orally days 1-14 and vinorelbine 25 mg/m2 intravenously days 1 and 8, for a maximum of six cycles. None of the patients had received prior chemotherapy for metastatic/advanced disease. Fifty-three per cent of patients with bone metastases and 67% of patients without bone metastases had visceral disease. The median age was 70 years for the 15 with bone involvement patients and 73 years for the 21 without bone involvement patients. RESULTS: Twenty-eight patients were fully evaluable for hematological dose-limiting toxicity (DLT), and all patients for other DLTs and for antitumor activity. One DLT with grade 3 venous thrombosis at dose level 2 and two dose-limiting neutropenia events at level 3 occurred in patients without bone involvement. Two dose-limiting neutropenia events were observed at dose level 2 for patients with bone involvement. Thus, the recommended dose was defined at level 1 (capecitabine 1000 mg/m2 days 1-14 and vinorelbine 20 mg/m2 days 1 and 8) for patients with bone involvement. For patients without bone involvement, the recommended dose was at level 2 (capecitabine 1250 mg/m2 days 1-14 and vinorelbine 20 mg/m2 days 1 and 8). For patients without bone involvement the overall response rate was 48% and the time to progression (TTP) was 4.5 months [95% confidence interval (CI) 3.3-6.9]. For patients with bone involvement the overall response rate was 53% and TTP was 5.3 months (95% CI 2.7-7.8). CONCLUSIONS: This regimen of capecitabine and vinorelbine is well tolerated and effective in elderly patients with metastatic breast cancer. Toxicity was mainly hematological and was observed at a lower dose in patients with bone involvement. A phase II study with the two different dose levels for elderly patients with and without bone involvement is currently being conducted.

Age Factors↗

[Metastasectomy--a direct therapeutic effect or an illusion due to patient selection?].

Metastasectomy is widely practiced in surgical oncology. Well established examples are the resection of liver metastases in patients with colo-rectal cancer, wedge resections of lung metastases in sarcoma, or the surgical removal of solitary brain metastases derived from solid tumours. The latter example has been tested in randomised phase III trials and found to be an effective mode of treatment compared with radiation therapy alone. In the other fields no such trials are available, and data chiefly stem from retro- and prospective phase II trials. For a variety of reasons, phase II studies are not suitable to separate confounding factors such as selection of good-risk patients, stage migration linked to the improvement of preoperative staging techniques, and improved supportive care, from the direct therapeutic effects of the surgical procedure as such. Although desirable, it is unlikely that surgeons and patients would accept randomised trials to reassess evidence levels in this field. In practice, large prospective studies of case series are likely to provide the highest evidence level achievable, and these limitations of the literature should be taken into account in an appropriate fashion when patients with metastatic cancer are advised about options for surgery.

Brain Neoplasms↗

[Quality assessment using AGIR: results and experience].

PURPOSE: To evaluate whether a new software from the working group for interventional radiology (AGIR) is an appropriate tool for quality assurance in interventional radiology, and presentation of results acquired within the quality improvement process in 1999. PATIENTS AND METHODS: AGIR-defined parameters such as patient data, risk profile, given interventions as well as complications were registered by a recently developed software. Based on monthly data analyses, possible complications were identified and discussed in morbidity and mortality conferences. RESULTS: 1014 interventions were performed in our institution in 1999. According to criteria established by AGIR, the complication rate was 2.7%. In addition and according to SCVIR criteria, complications were distinguished quantitatively in five classes and semiquantitatively in minor and major groups. The result was a minor complication rate of 1.8%, and a major rate of 0.9%. There were no cases of death associated with the intervention. Further strategies were developed in order to reduce the complication rate. CONCLUSION: Extensive quality assurance methods can be integrated in daily routine work. These methods lead to an intensive transparency of treatment results, and allow the implementation of continuous quality improvements. The development of the software is a first step in establishing a nation-wide quality assurance system. Nevertheless, modification and additional definition of the AGIR predefined parameters are required, for example, to avoid unnecessary procedures.

Adolescent↗

Vascular response to gadolinium-containing contrast media in an ex vivo rabbit arterial model.

RATIONALE AND OBJECTIVES: To assess the influence of gadolinium-containing magnetic resonance contrast agents on contractility of the arterial vessel wall. METHODS: Bilateral segments of rabbit carotid arteries were mounted in flow chambers, surrounded by aerated (95% O2, 5% CO2) Krebs' solution, and perfused at a constant rate by separated and aerated Krebs' solution. Therefore, changes in pressure of the circulating Krebs' solution indicated alterations of vessel wall contractility. Viability of the artery was tested by 124 mmol/L KCl, 3 x 10-5 mol/L phenylephrine, and 10-5 mol/L acetylcholine. After a washout phase, gadopentate (n = 10) or gadoteridol (n = 10) was added to the perfusate of one carotid artery in increments of 0.1, 0.3, and 0.6 mmol/L. Concentrations up to 0.9 mmol/L and 1.2 mmol/L were tested, respectively. The contralateral artery served as a control. To assess potential relaxing effects of the media, vessels were brought into a contracted status with 3 x 10-5 mol/L phenylephrine and then received gadolinium chelates. RESULTS: Potassium chloride and phenylephrine increased and acetylcholine decreased the pressure, indicating vasoconstriction and vasodilatation, respectively. After gadopentate and gadoteridol infusion, no statistically significant pressure changes could be detected, ruling out any vasoconstrictor or vasodilator effect. CONCLUSIONS: Gadopentetate and gadoteridol in doses of up to 1.2 mmol/L did not alter vessel wall tone. The impact of contrast media on blood pressure, as has been shown in some clinical trials, probably is not due to direct changes in arterial wall tone.

Animals↗

[Angiography detection of closed palmar arcs].

PURPOSE: Angiographic evaluation of the prevalence of an anastomosis between the superficial and deep palmer arcs in our patients. MATERIALS AND METHODS: Between January 1st 1991 and December 31st 1997, all selectively performed angiographies of the upper extremities were evaluated retrospectively with special focus on an anastomosis between the superficial palmer arc (SPA) and the deep palmer arc (DPA). The indications for performing a selective angiography of the upper extremity were presurgical planning of a skin/muscle transplantation (n = 42), creation of a hemodialysis fistula (n = 4) and evaluation of vascular diseases such as vasculitis (n = 9), peripheral occlusive disease (n = 3) and M. Winiwarter-Buerger (n = 8). RESULTS: 66 selective angiographies of the palm of 60 patients (39 male, 21 female, mean age 52 years old) could be used for evaluation. Angiographies of both hands were performed in 6 patients. Closed superficial palmar arcs and closed deep palmar arcs were detected in 31.8% and 84.8% of the patients, respectively. CONCLUSIONS: The rates of anastomosed superficial and deep palmar arcs in our study are comparable with those of former angiographic investigations, but they are considerably lower than the rates based on anatomical or sonographical studies. Reasons for the discrepancy are discussed.

Adult↗

Herpesvirus entry mediator HVEM mediates cell-cell spread in BHK(TK-) cell clones.

95-19 and U(S)11c119.3 are BHK(TK-)-derived cell lines that are highly resistant to postattachment entry of herpes simplex virus type 1 (HSV-1) and HSV-2 but not to later steps in single-step replication. The resistance properties of these two cell types are not identical. U(S)11c119.3 cells are fully susceptible to pseudorabies virus (PRV), as shown by single-step growth experiments, whereas 95-19 cells are resistant to entry of free PRV but not to entry by cell-cell spread. We have tested the ability of HVEM to overcome the block to infection in both cell lines following transient and stable transfection. HVEM was able to mediate entry of free HSV-1 into both cell lines, as shown by an increase in the number of beta-galactosidase-expressing cells in cultures transiently transfected with an HVEM expression plasmid and infected with lacZ-expressing HSV-1. In stably transfected 95-19 cells, HVEM enhanced infection by free HSV-1, as shown by an increase in the number of infectious centers obtained following infection. In both cell types, HVEM strongly enhanced entry of HSV-1 and HSV-2 by cell-cell spread, suggesting that HVEM can function as an entry mediator both in entry of free virus and in entry by cell-cell spread.

Cell Line↗

The exon splicing silencer in human immunodeficiency virus type 1 Tat exon 3 is bipartite and acts early in spliceosome assembly.

Inefficient splicing of human immunodeficiency virus type 1 (HIV-1) RNA is necessary to preserve unspliced and singly spliced viral RNAs for transport to the cytoplasm by the Rev-dependent pathway. Signals within the HIV-1 genome that control the rate of splicing include weak 3' splice sites, exon splicing enhancers (ESE), and exon splicing silencers (ESS). We have previously shown that an ESS present within tat exon 2 (ESS2) and a suboptimal 3' splice site together act to inhibit splicing at the 3' splice site flanking tat exon 2. This occurs at an early step in spliceosome assembly. Splicing at the 3' splice site flanking tat exon 3 is regulated by a bipartite element composed of an ESE and an ESS (ESS3). Here we show that ESS3 is composed of two smaller elements (AGAUCC and UUAG) that can inhibit splicing independently. We also show that ESS3 is more active in the context of a heterologous suboptimal splice site than of an optimal 3' splice site. ESS3 inhibits splicing by blocking the formation of a functional spliceosome at an early step, since A complexes are not detected in the presence of ESS3. Competitor RNAs containing either ESS2 or ESS3 relieve inhibition of splicing of substrates containing ESS3 or ESS2. This suggests that a common cellular factor(s) may be required for the inhibition of tat mRNA splicing mediated by ESS2 and ESS3.

Base Sequence↗

Comparative regulation of alpha1-adrenergic receptor mediated contraction in urogenitally derived smooth muscle. Effect of epidermal growth factor.

Contractility of smooth muscle within mammalian urogenital organ systems has an established role in physiological/pathophysiological functioning of the component structures. Our aim was to examine the direct effect of epidermal growth factor (EGF) on smooth muscle tone as well as its indirect effects in regulating alpha1-adrenoceptor-mediated contraction of the prostate, the vas deferens and renal arteries. Tissues were mounted isometrically, under controlled conditions, and changes in tension in response to treatment with phenylephrine (PE) with or without pretreatment with EGF were recorded on a physiological recorder via force transducers. In the rabbit prostate, EGF potentiated the magnitude of contraction to PE. The potentiation appeared to be dependent on cyclo-oxygenase products. In the human prostate, EGF potentiated the contractile response to PE. EGF had no effect on the PE-induced contraction of the rabbit renal artery and vas deferens. EGF alone did not alter smooth muscle tone in any of the above-mentioned tissues. The main finding of this study is the difference in the regulation by EGF of the alpha1-adrenoceptor-mediated response in smooth muscle of the prostate, from that by the vas deferens and renal artery. The reasons for this difference in response remain to be elucidated. This study may form the basis for further investigation into receptor transregulation and its relevance to symptomatic benign prostatic hyperplasia (BPH).

Animals↗

Variable effects of iodinated contrast media on different rabbit arteries in vitro.

Vasoconstriction caused by iodinated contrast media (CM) has been considered specific for the renal artery only. We examined the vascular effect of CM in rabbit carotid, aorta, renal, iliac, mesenteric and celiac arteries and found that other arteries also respond with a contraction to CM. Isolated arterial rings were exposed to diatrizoate (high osmolar CM), iohexol (low osmolar CM) or glucose solution, and the isometric contraction response was expressed as percentage of an initial KCl control contraction. Diatrizoate evoked contractions of 82% (carotid), 63% (aorta), 30% (renal), 24% (iliac), 28% (mesenteric) and 18% (celiac), respectively. Iohexol caused contractions of 31% (carotid), 24% (aorta), 15% (renal) and 14% (iliac), whereas the mesenteric and celiac arteries were relaxed by iohexol. A high osmolar glucose solution elicited contractions of 78%, 77%, 11%, 27%, 3% and 5%, respectively, in the arteries. CM have contraction potency in arterial vasculature other than the renal artery.

Animals↗

Comparison of iodinated contrast media-induced renal vasoconstriction in human, rabbit, dog, and pig arteries.

RATIONALE AND OBJECTIVES: Contrast media (CM)-induced renal vasoconstriction is an important factor in the pathogenesis of CM-induced nephrotoxicity. The effects of ionic, high-osmolar CM sodium/meglumine diatrizoate and nonionic, low-osmolar CM iohexol and iopamidol were studied in rabbit, dog, and pig renal arteries and compared with human tissue in an organ bath. METHODS: Isometric contractions were induced by increasing concentrations of CM and high-osmolar glucose solution. RESULTS: Contrast media and glucose elicited contractions in human renal arteries of 32% (diatrizoate), 20% (iohexol), 30% (iopamidol), and 22% (glucose). Rabbit and dog renal arteries demonstrated contractions of 30% and 46% (diatrizoate), 15% and 23% (iohexol), 15% and 26% (iopamidol), and 11% and 40% (glucose), respectively, of the control. There was a vasorelaxing effect of all CM tested on pig renal artery. CONCLUSIONS: Responses in rabbit and dog renal arteries were similar to those in human renal arteries and could serve as models for investigating CM-induced renal vasoconstriction.

Animals↗

Effect of contrast medium on corpus cavernosum smooth muscle.

RATIONALE AND OBJECTIVES: Changes in contractility of corpus cavernosum (CC) smooth muscle caused by radio contrast medium may result in misinterpretations of cavernosography used diagnostically in erectile dysfunction. METHODS: The authors investigated the direct effect of various contrast media on rabbit CC smooth muscle tissue strips in an in vitro model by adding contrast medium to the tissue in a perfusion bath and recording the resulting contractions. Glucose addition was used as control. RESULTS: Application of high-osmolar, ionic contrast medium diatrizoate-induced CC smooth muscle contractions of 57% of the control potassium chloride (124 mM) induced contractions. The low-osmolar (862 mOsm/kg) nonionic monomer contrast medium, iohexol, and the iso-osmolar (300 mOsm/kg) nonionic-dimer contrast medium, iodixanol, elicited contractions of 34% and 36% of the potassium chloride control contractions, respectively. High- and Iso-osmolar glucose solutions caused contractions of 51%, 38%, and 24% of the control, respectively. Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) regulate CC smooth muscle contractions. These are influenced by different drugs including phosphodiesterases (PDEs), forskolin, and 3-morpholinsydnonimine hydrochloride (SIN-1). The nonspecific PDE inhibitors papaverine (0.1 mM) and theophylline (1 mM) reduced the contrast medium-induced contractions to 66% and 69%, respectively. The specific PDE inhibitor milrinone (0.1 mM) reduced the contractions to 69%; 0.1 mM forskolin and SIN-1 reduced the contractions to 34% and 41%, respectively. CONCLUSIONS: Contrast medium induces CC smooth muscle contractions, depending mainly on the osmolality of the solution. The contractions are reduced but not abolished by elevating the intracellular cAMP and cGMP concentrations. The clinical applications in cavernosography are discussed.

Animals↗

Role of intracellular calcium stores in contrast medium-induced renal vasoconstriction.

RATIONALE AND OBJECTIVES: Renovascular smooth muscle contractility, an important factor in contrast media-induced nephrotoxicity, depends on intracellular Ca2+ concentration, which is composed of extracellular Ca2+ influx and intracellular Ca2+ release. These factors were investigated in contrast media-induced renal vasoconstriction in an in vitro model. METHODS: KCl-induced isometric contractions of rabbit renal artery were compared with contractions elicited by contrast media (diatrizoate, iohexol, iopamidol). Measurements were made after incubation with the Ca2+ channel blockers nifedipine, verapamil, and diltiazem to assess the role of extracellular Ca2+ influx and after ryanodine and thapsigargin to investigate the role of intracellular Ca2+ release. RESULTS: The Ca2+ channel blockers partially inhibited contractions induced by contrast media, while KCl-induced contractions were completely abolished. Ryanodine and thapsigargin also markedly inhibited contrast media-induced contractions. CONCLUSION: Ionic and nonionic contrast media induced quantitatively different renal vasocontractions. Ca2+ channel blockers inhibited this vasocontraction only slightly compared with intracellular Ca2+ release blockers.

Animals↗

Contrast medium induced renal vasoconstriction, role of alpha receptors.

Standard imaging techniques for evaluation of renal and renovascular disease require the application of radiocontrast medium. The use of high osmolar, ionic radio contrast medium is however associated with adverse effects including acute renal insufficiency. Renal vasoconstriction seems to play an important role in the pathomechanism of this side effect. The cellular mechanisms however remain unsolved. Alpha 1-adrenoceptors and their subtypes are the crucial link between sympathetic stimulation and renal vasoconstriction. We investigated the role of alpha 1-receptors and the alpha 1A and alpha 1B subtypes in the renal artery and in sodium/meglumine diatrizoate induced renal artery smooth muscle contraction. Alpha 1-receptor induced rabbit renal artery contraction was produced by stimulation with the specific agonist phenylephrine which was antagonized dose-dependently and reversibly by the alpha 1-blockers prazosin, terazosin and YM 617. The alpha 1A-receptor was the prevalent receptor subtype in rabbit renal artery. This was identified by applying the specific alpha 1A-receptor antagonist 5-methylurapidil and the irreversible alpha 1B-receptor antagonist chloroethyllonidine. These two inhibited the PE induced contraction by 96% and 66%, respectively. Sodium/meglumine diatrizoate elicited renal artery contraction at 25% of the phenylephrine control. This contraction was not influenced by alpha 1-blockers indicating the absence of an alpha 1-receptor mediated process.

Adrenergic alpha-Agonists↗

Evaluation of oxycodone and acetaminophen in treatment of postoperative dental pain.

Although both acetaminophen and oxycodone are commonly used analgesics, they were not available as a combination until recently. Since oxycodone is not available as a single entity, there is no archival or even anectodal information on the efficacy and safety of this combination. The purpose of this study was to evaluate the relative efficacy of various doses of the combination that could be used in dental situations. The single-dose efficacy and safety of acetaminophen 500 mg., oxycodone 5 mg., acetaminophen 500 mg. + oxycodone 5 mg., acetaminophen 1,000 mg. + oxycodone 5 mg., acetaminophen 1,000 mg. + oxycodone 10 mg., and placebo were compared in outpatients who experienced moderate to severe pain after surgical removal of inpacted third molars. Analgesic data were analyzed by analysis of variance and Duncan's multiple range test. All active treatments were superior to placebo, with the high-ratio combination being the most efficacious. This treatment also had the highest incidence of limiting side effects. A positive dose-effect relationship was evident for both acetaminophen 500 mg. and 1,000 mg. and for oxycodone 5 mg. and 10 mg.

Acetaminophen↗