Search PubMed⌕ Search

Biomedical subjects

H Riess

Publications and source records attributed to H Riess.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Thrombophilia--diagnostic steps and therapeutic consequences after deep vein thrombosis].

SUMMARY: In developed countries there is an age dependent increasing incidence of deep vein thrombosis. Hereditary thrombophilia is usually suspected by the clinical constellation and anamnestic informations. For economical reasons usually laboratory testing should be avoided if the results will not change directly the therapeutic process. But for hereditary defects consequences for the patient in future and for relatives should be taken into account especially as more selective strategies for prophylaxis and treatment have to be expected by increasing information in that field of research. As deficiencies of anticoagulant proteins (PC, PS, AT) have an impact on anticoagulant treatment, the indication for testing should not be held too strict. Time point for diagnostic procedures should be early after a thromboembolic event as negative results exclude hereditary defects definitely which allows the planning of the aimed treatment duration. After first onset of deep vein thrombosis, even in presence of hereditary coagulation defects the duration of anticoagulation usually depends on the clinical and anamnestic signs for a thrombophilic tendency of the individual patient. First publications suggest the need for prolonged anticoagulation of carriers with combined defects, showing an elevated rate of re-thrombosis after the first thromboembolic event, when anticoagulation is stopped. Every ongoing anticoagulation should be checked repeatedly in the sense of a risk -benefit evaluation even for patients with a thrombophilic tendency and should be adapted to actual publications.

Humans↗
PubMed2002

[T4 rectal carcinoma. Surgical and multimodal therapy].

BACKGROUND: In locally advanced rectal cancer with infiltration of neighbouring organs (uT4), resectability and local control are difficult to achieve. Combined preoperative radiochemotherapy may result in increased resectability and reduced local recurrence rates. PATIENTS AND METHODS: Thirty-four patients with biopsy-proven locally advanced rectal cancer were treated by preoperative radiochemotherapy. All tumours had been staged as uT4 lesions by endorectal ultrasound or computed tomography. Radiotherapy was applied in standard blocks, 5 x 1.8 Gy up to 45 Gy. Chemotherapy consisted of two cycles of 5-fluorouracil (300-350 mg/m2/day) and leucovorin (50 mg). In 20 patients, additional thermotherapy was carried out using the Sigma 60 applicator BSD 2000 once a week prior to radiotherapy. Surgery was performed 4-6 weeks after radiochemotherapy. Postoperatively, all patients received four cycles of 5-fluorouracil and leucovorin. RESULTS: Treatment-induced toxicity occurred in 26% of the patients (WHO grade III (n = 6) and IV (n = 3)). The resectability rate was 76% (26/34 patients) (R0 resectability n = 21; 62%). The pathological complete response rate was 6% (n = 2) and the partial response rate was 47% (n = 16). A local failure was observed in six patients after median time of 16 months (range 7-36 months). Patients with R0 resection achieved a 5-year disease-free survival rate of 55% and a survival rate of 71%. The overall 5-year survival rate for all patients with advanced uT4 rectal cancer was 49%. CONCLUSIONS: Our data on preoperative combined treatment in locally advanced T4 rectal cancer revealed encouraging downstaging, local control, and survival rates.

Adult↗
PubMed2002

Hyperthermia in combined treatment of cancer.

Hyperthermia, the procedure of raising the temperature of tumour-loaded tissue to 40-43 degrees C, is applied as an adjunctive therapy with various established cancer treatments such as radiotherapy and chemotherapy. The potential to control power distributions in vivo has been significantly improved lately by the development of planning systems and other modelling tools. This increased understanding has led to the design of multiantenna applicators (including their transforming networks) and implementation of systems for monitoring of E-fields (eg, electro-optical sensors) and temperature (particularly, on-line magnetic resonance tomography). Several phase III trials comparing radiotherapy alone or with hyperthermia have shown a beneficial effect of hyperthermia (with existing standard equipment) in terms of local control (eg, recurrent breast cancer and malignant melanoma) and survival (eg, head and neck lymph-node metastases, glioblastoma, cervical carcinoma). Therefore, further development of existing technology and elucidation of molecular mechanisms are justified. In recent molecular and biological investigations there have been novel applications such as gene therapy or immunotherapy (vaccination) with temperature acting as an enhancer, to trigger or to switch mechanisms on and off. However, for every particular temperature-dependent interaction exploited for clinical purposes, sophisticated control of temperature, spatially as well as temporally, in deep body regions will further improve the potential.

Animals↗
PubMed2002

Monitoring arterial blood pressure during whole body hyperthermia.

BACKGROUND: For monitoring of arterial blood pressure (ABP) during whole body hyperthermia (WBH) different methods have been recommended. This investigation was performed to evaluate the agreement of invasive measurements at various sites, and to compare invasive and non-invasive methods of ABP monitoring under conditions of a heat-induced extreme vasodilation. METHODS: In 19 patients, 48 treatments with WBH were performed. Measurements of ABP in the radial and femoral artery by oscillometry and by sphygmomanometry were taken at four temperature levels during WBH (37, 40, 41.8 and 39 degrees C). RESULTS: Significant differences were observed between invasive and non-invasive methods for systolic ABP, with higher values for non-invasive measurements. When compared with both invasive measurements for diastolic blood pressures, sphygmomanometry gave higher values and oscillometry gave lower values. Sphygmomanometry also showed higher values for mean ABP compared with all other techniques, while measurements in radial and femoral artery and by oscillometry only differed by approximately 5 mmHg. CONCLUSION: The mean arterial pressure and not the systolic and/or diastolic pressure should guide hemodynamic management during WBH. The sphygmomanometric technique is not recommended for use during hyperthermia.

Adult↗
PubMed2002

Phase I study of gemcitabine in combination with cisplatin, 5-fluorouracil and folinic acid in patients with advanced esophageal cancer.

The prognosis for advanced esophageal carcinoma is poor with a median survival of 9-12 months and 5-year-survival rate of 10-20%. Combination chemotherapy with cisplatin and 5-fluorouracil (5-FU) is considered to be the standard therapy, but has a high potential of side effects and is usually not given on an ambulatory basis. This phase I study was designed to find the maximum tolerated dose (MTD) of weekly cisplatin in combination with standard doses of gemcitabine (1,000 mg/m(2), 30 min) and 5-FU (750 mg/m(2), 24 h)/folinic acid (200 mg/m(2), 30 min). All drugs were to be given on a day 1, 8, 15 and 22 of a 6-weekly cycle in an outpatient setting. Nineteen chemonaive patients with inoperable stage IIa, III and IV squamous cell carcinoma and adenocarcinoma of the esophagus were enrolled into the study. Eight, six and five patients were enrolled at cisplatin dose levels 0 (20 mg/m(2) ), I (25 mg/m(2) ) and II (30 mg/m(2)), respectively. One hundred and eighty-one out of 187 treatments (55 cycles) were given on an outpatient basis. The dose-limiting toxicities of this schedule were leukopenia and thrombocytopenia. Other side effects were mild. Dose level II (30 mg/m(2)) was defined as the MTD for cisplatin when used in this combination and schedule. Partial responses were observed in 10 of the 19 enrolled patients. The side effect profile seen in this study in combination with the preliminary evidence of efficacy justifies further testing in a phase II setting with a cisplatin dose of 25 mg/m(2) and offers a treatment option for patients in an outpatient setting.

Adenocarcinoma↗
PubMed2001

[Radiochemotherapy plus hyperthermia in rectal carcinoma].

In locally advanced rectal cancer (uT3/uT4) resectability as well as local control is reduced. In the patients combined preoperative radiochemotherapy demonstrated an increase of resectability and a reduction of local recurrence. Radiotherapy was applied in standard blocks, 5 x 1.8 Gy up to 45 Gy. Chemotherapy consisted out of two cycles of 5-Fluorouracil (300-350 mg/m2/d) and Leucovorin (50 mg). Prior to radiotherapy additionally thermotherapy was carried out using the SIGMA 60 applicator BSD 2000 once a week. The hyperthermia method is based on heating up affected tissue compartments to temperature above 42 degrees Celsius without damaging surrounding tissue compartments. In regional hyperthermia tumors in the abdominal region are treated by emitting radio waves into the patient. 4-6 weeks after radiochemotherapy, surgery was performed. The therapeutic toxicity was acceptable and the resectability rate was up to 90%. Response rate to treatment was 60%. Our data with preoperative combined treatment in locally advanced rectal cancer revealed encouraging downstaging, local control, and survival rates.

Chemotherapy, Adjuvant↗
PubMed2001

[Secondary osteoporosis induced by anticoagulants?].

Generalized osteoporosis is a result of different causes and pathogenic mechanisms, which often combine forces to become clinically relevant. Among the different exogenic factors, drugs play an important role, frequently in connection with other factors such as immobilization or pregnancy. It has been suggested that anticoagulation therapy with heparins or coumarins may induce osteoporotic changes or enhance the development of osteoporosis for other reasons. According to in vitro experiments, preclinical trials, and clinical investigations, it seems reasonable to assume that heparins induce increased bone loss in a time- and dose-related manner. Low-molecular-weight heparins most likely have less effect on bone turnover when compared to unfractionated heparin. Oral anticoagulation therapy with vitamin K-antagonists is believed to have a weak effect on induction of osteoporosis, but clinical studies are contradictory. In spite of the fact that a relevant effect of these drugs on the induction of osteoporosis is questionable, it must be taken into consideration that anticoagulant drugs may enhance the negative effects on bone density of other risk factors capable of inducing osteoporosis such as immobilization, pregnancy, or endocrinological disorders.

Administration, Oral↗
PubMed2001

Recombinant human erythropoietin in the treatment of head and neck tumour anaemia.

At the time of first diagnosis, patients with squamous cell carcinoma in the head and neck are often in the advanced stage of their disease, therefore surgery is not a viable option for treatment. These patients also present frequently a high grade of anaemia as a result of either the malignant process itself or of the following therapy. The incidence of anaemia and the need for transfusion depends on several factors, such as the type and intensity of radiotherapy and radiochemotherapy. Multimode therapeutic concepts such as radio-chemotherapy are being applied with increasing frequency, resulting in an ever increasing need for transfusion with great effects on the patient's quality of life. Even more important to tumour patients is the role of the haemaglobin (Hb) value as a prognostic factor for survival and/or local tumour control. A large number of studies show that recombinant human erythropoietin (r-HuEPO) is effective in the treatment of tumour-induced anaemia and prevention and correction of chemotherapy and radiotherapy-induced anaemia. The simultaneous application of r-HuEPO with chemotherapy can prevent patients with head and neck tumours from developing anaemia or can reduce the extent of the anaemia and the need for transfusion. Comparable effects were observed both in patients undergoing platinum-based and non-platinum-based chemotherapy. The direct correlation between anaemia, tumour hypoxia and poor response to radio and/or chemotherapy has been clinically proven. Recombinant human erythropoietin administration improves the therapeutic outcome and the patients' prognosis.

Anemia↗
PubMed2001

Platelet activation through triathlon competition in ultra-endurance trained athletes: impact of thrombin and plasmin generation and catecholamine release.

The aims of this study were to evaluate whether platelets are activated during strenuous exercise in healthy athletes. Also, to determine the impact of plasmin and thrombin activity and catecholamine release. Previous studies have shown activation of the hemostatic system after competitive exercise, but platelet activation was thought to be absent in trained athletes. The impact of thrombin and other potent platelet activators is still a matter for debate. We examined 30 healthy triathletes during a triathlon competition. Flow cytometric detection of CD62p (P-selectin) was used to measure in vivo activation of platelets. Platelet-leukocyte aggregates were also determined. Thrombin concentration was assessed by the thrombin-antithrombin III complex (TAT) and the fibrinolytic state was characterised by the plasmin-alpha2-antiplasmin complex (PAP). Catecholamines were measured by means of high-pressure liquid chromatography. CD62p rose from baseline (2.3%) to 3.4% and was still elevated after 2 hours (3.1%, p = 0.0133). Platelet-leukocyte aggregates were elevated 30 min after exercise (4.3 % vs 3.6%) and decreased significantly after 60 min (2.9 %, p = 0.008). TAT increased from 3.9 microg/l to 8.3 microg/l after competition and to 5.4 microg/l 2 hours later (p < 0.001). PAP increased 10-fold from 350 microg/l to 3,267 microg/l after the triathlon and was still elevated after 2 hours (1,074 microg/l, p<0.001). No linear correlation was found between the hemostatic markers, catecholamines and platelet activation. Platelets, coagulation and fibrinolysis are activated by competitive exercise in athletes, whereby fibrinolytic changes are pronounced. Mechanisms of platelet activation during exercise include phenomena other than plasmatic hemostatic factors and catecholamines.

Adult↗
PubMed2001

[Radiological-guided liver-port implantation: Evaluation, technical approach, interventional procedure and follow up].

UNLABELLED: Radiological-guided liver-port implantation: Evaluation, technical approach, interventional procedure and follow up. PURPOSE: Description of evaluation, technical approach, interventional procedure and follow up of radiological-guided liver-port implantation. METHOD: Percutaneous implantation of a liver-port system was performed in twelve patients through a transfemoral approach and in one patient via the superficial epigastric artery after surgical exploration. In four patients we used port systems which are accessible via ventral puncture. Strecker-port systems were implanted in the remaining nine patients. RESULTS: The liver-port implantation was technically successful in all cases. No dislocation of the distal catheter tip, no thrombosis of the hepatic or splenic artery, no leakage near connections of the catheters or connections of catheter and port system and no thrombosis of the femoral arteries were observed. Correction of a kink in the catheter was performed in one patient. Another patient showed prolonged healing of the subcutaneous pocket. CONCLUSIONS: Interventional liver-port implantation is a safe procedure and leads to good clinical results. From the view of the radiologist the Strecker-system shows a good performance. The approach via the superficial epigastric artery demands excellent interdisciplinary cooperation.

Angiography↗
PubMed2001

Anticoagulation: the present and future.

Thrombin is a central bioregulator of coagulation and is therefore a key target in the therapeutic prevention and treatment of thromboembolic disorders, including deep vein thrombosis and pulmonary embolism. The current mainstays of anticoagulation treatment are heparins, which are indirect thrombin inhibitors, and coumarins, such as warfarin, which modulate the synthesis of vitamin K-dependent proteins. Although efficacious and widely used, heparins and coumarins have limitations because their pharmacokinetics and anticoagulant effects are unpredictable, with the risk of bleeding and other complications resulting in the need for close monitoring with their use. Low-molecular-weight heparins (LMWHs) provide a more predictable anticoagulant response, but their use is limited by the need for subcutaneous administration. In addition, discontinuation of heparin treatment can result in a thrombotic rebound due to the inability of these compounds to inhibit clot-bound thrombin. Direct thrombin inhibitors (DTI) are able to target both free and clot-bound thrombin. The first to be used was hirudin, but DTIs with lower molecular weights, such as DuP 714, PPACK, and efegatran, have subsequently been developed, and these agents are better able to inhibit clot-bound thrombin and the thrombotic processes that take place at sites of arterial damage. Such compounds inhibit thrombin by covalently binding to it, but this can result in toxicity and nonspecific binding. The development of reversible noncovalent DTIs, such as inogatran and melagatran, has resulted in safer, more specific and predictable anticoagulant treatment. Oral DTIs, such as ximelagatran, are set to provide a further breakthrough in the prophylaxis and treatment of thrombosis.

Administration, Oral↗
PubMed2000

[Adjuvant therapy of pancreatic carcinoma].

The poor prognosis in pancreatic carcinoma has been increased especially by improved diagnostic procedures and decreasing perioperative mortality. Median survival after complete resection is commonly less than 20 months and the 5 years survival is in the range of about 20%. Postoperative radiochemotherapy reduces the local recurrence rate but not the overall survival however. Pancreatic carcinoma is characterized by a low chemosensitivity of the drugs commonly used like 5-FU. More aggressive chemotherapy protocols are limited by the reduced status of the patient. Multimodal and prolonged adjuvant schedules did not show a prognostic benefit. The current ESPAC--study investigates the role of simultaneous radiotherapy and 5-FU alone or in combination with neoadjuvant 5-FU and folic acid for 6 months. New protocols will investigate the value of regional adjuvant chemotherapy ESPAC 2) [44] and of gemcitabine, 5-FU or control in a three arm study.--In a multicenter German trial the benefit of gemcitabene as weekly monotherapy for 6 months is investigated. The treatment starts soon after resection due to low toxicity and good patient compliance.

Combined Modality Therapy↗
PubMed2000

Preoperative radiochemotherapy in locally advanced or recurrent rectal cancer: regional radiofrequency hyperthermia correlates with clinical parameters.

PURPOSE: Preoperative radiochemotherapy (RCT) is a widely used means of treatment for patients suffering from primary, locally advanced, or recurrent rectal cancer. We evaluated the efficacy of treatment due to additional application of regional hyperthermia (HRCT) to this conventional therapy regime in a Phase II study, employing the annular phased-array system BSD-2000 (SIGMA-60 applicator). The clinical results of the trial were encouraging. We investigated the relationship between a variety of thermal and clinical parameters in order to assess the adequacy of thermometry, the effectiveness of hyperthermia therapy, and its potential contribution to clinical endpoints. METHODS AND MATERIALS: A preoperative combination of radiotherapy (1.8 Gy for 5 days a week, total dose 45 Gy applied over 5 weeks) and chemotherapy (low-dose 5-fluorouracil [5-FU] plus leucovorin in the first and fourth week) was administered to 37 patients with primary rectal cancer (PRC) and 18 patients with recurrent rectal cancer (RRC). Regional hyperthermia (RHT) was applied once a week prior to the daily irradiation fraction of 1.8 Gy. Temperatures were registered along rectal catheters using Bowman thermistors. Measurement points related to the tumor were specified after estimating the section of the catheter in near contact with the tumor. Three patients with local recurrence after abdominoperineal resection, had their catheters positioned transgluteally under CT guidance, where the section of the catheter related to the tumor was estimated from the CT scans. Index temperatures (especially T(max), T(90)) averaged over time, cumulative minutes (cum min) (here for T(90) > reference temperature 40.5 degrees C), and equivalent minutes (equ min) (with respect to 43 degrees C) were derived from repetitive temperature-position scans (5- to 10-min intervals) utilizing software specially developed for this purpose on a PC platform. Using the statistical software package SPSS a careful analysis was performed, not only of the variance of thermal parameters with respect to clinical criteria such as toxicity, response, and survival but also its dependency on tumor characteristics. RESULTS: The rate of resectability (89%) and response (59%) were high for the PRC group, and a clear positive correlation existed between index temperatures (T(90)) and thermal doses (cum min T(90) >/= 40.5 degrees C). Even though the overall 5-year survival was encouraging (60%) and significantly associated with response, there was no statistically significant relationship between temperature parameters and long-term survival for this limited number of patients. However, nonresectable tumors with higher thermal parameters (especially cum min T(90) >/= 40.5 degrees C) had a tendency for better overall survival. We found even higher temperatures in patients with recurrences (T(90) = 40.7 degrees C versus T(90) = 40.2 degrees C). However, these conditions for easier heating did not involve a favorable clinical outcome, since surgical resectability (22%) and response rate (28%) for the RRC group were low. We did not notice any other dependency of thermal parameters to a specific tumor or patient characteristics. Finally, neither acute toxicity (hot spots) induced by hyperthermia or RCT nor perioperative morbidity were correlated with temperature-derived parameters. Only a higher probability for the occurrence of hot spots was found during treatment with elevated power levels. CONCLUSION: In this study with two subgroups, i.e., patients with PRC (n = 37) and RRC (n = 18), there exists a positive interrelationship between thermal parameters (such as T(90), cum min T(90) >/= 40,5 degrees C) and clinical parameters concerning effectiveness. Additional hyperthermia treatment does not seem to enhance toxicity or subacute morbidity. Procedures to measure temperatures and to derive thermal parameters, as well as the hyperthermia technique itself appear adequate enough to classify heat treatments in

Age Factors↗
PubMed2000

[The importance of delay in patients with tumors exemplified by pretreatment of locally advanced rectal carcinoma].

BACKGROUND: With the intention to achieve tumor reduction and thereby increase R0-resection rate, preoperative radiochemotherapy is increasingly applied in locally advanced rectum cancer. Along with the advantages of prior therapy, a delay of surgical treatment occurs which might despite continuing therapy give way to local tumor progression or metastatic disease. PATIENTS AND METHODS: Since 1993 we have treated locally advanced rectum carcinomas by preoperative radiotherapy according to a preoperative study protocol. We analyzed the incidence of local tumor progression or metastases during the 12 weeks of preoperative treatment. Hundred and fifteen patients with histologically proven primary rectum carcinoma without evidence of regional or distant metastases and endosonographically determined infiltration depth of stage T3 or more underwent preoperative radiochemotherapy between 3/1993 and 10/1999. Hundred and eight patients (88 times uT3 and (20 times uT4) have been operated and examined afterwards with respect to response to prior treatment. Before and after preoperative therapy, endorectal ultrasound was performed to evaluate local response. Distant metastatic manifestations were excluded by radiography and ultrasound scanning. RESULTS: A reduction of the infiltration depth was observed in 55 patients (51%). Tumor size remained unchanged in 50 patients (46%). Only 3 patients (3%) showed tumor growth in histological assessment. Fifty-seven patients (53%) showed no change in lymph node status after preoperative therapy, whereas lymph node metastases were detected in 11 patients (10%) who were judged uN0 preoperatively. We discovered metastases in 6 patients (6%) after preoperative therapy. CONCLUSION: During preoperative therapy, tumor progress is not entirely evitable. Considering the lack of precision in pretherapeutic staging diagnostics, we conclude that delays due to therapeutic regimen are responsible for prognostic disadvantage in only a small number of patients.

Antimetabolites, Antineoplastic↗