PubMed Health⌕ Search

Biomedical subjects

R Eckel

Publications and source records attributed to R Eckel.

At least 19 recordsLinked to original sources
PubMed2006

Theoretical analysis of single-molecule force spectroscopy experiments: heterogeneity of chemical bonds.

We show that the standard theoretical framework in single-molecule force spectroscopy has to be extended to consistently describe the experimental findings. The basic amendment is to take into account heterogeneity of the chemical bonds via random variations of the force-dependent dissociation rates. This results in a very good agreement between theory and rupture data from several different experiments.

Biomechanical Phenomena↗
PubMed2005

Survival for rectal cancer patients and international comparisons.

BACKGROUND: Population-based cancer registry data are important because they reflect routine care, present long-term follow-up, can show differences in treatment, outcomes and health care over time, and can be used for comparisons between regions and countries. PATIENTS AND METHODS: Details of all cancer patients in the Munich region are recorded by the Munich Cancer Registry. Rectal cancer patients with an invasive primary tumor diagnosed between 1996 and 1998 were included in this analysis (n=936). Observed and relative survival are presented. Observed survival was also investigated with a Cox proportional hazards regression model. RESULTS: Median follow-up time of survivors was 5.7 years. Five-year relative survival for the whole sample was 62.2%. International Union Against Cancer (UICC) stage was the most important prognostic factor in the multivariate analysis. Compared with the 1992-1999 Surveillance Epidemiology and End Results (SEER) data (62.4%), relative survival for each disease stage and the whole sample were very similar. In comparison with other European registries, Munich patients had slightly higher survival rates per stage (for example, 5-year relative survival in UICC III was 58.3% in Munich, 54.6% in South East Netherlands, 33.3% in Modena and 47.4% in Cote d'Or); however, more patients in Munich were in higher disease stages with worse prognoses, indicating poorer early detection. CONCLUSIONS: These results indicate that treatment of rectal cancer in Munich is good, but early detection could be improved. Cancer registries should publish their population-based stage data to ensure quality of care and provide regular feedback to health-care workers and decision makers. Comparisons between countries without stage data should be conducted cautiously.

Aged↗
PubMed2005

[Salivary gland carcinomas. 1. Epidemiology, etiology, malignancy criteria, prognostic parameters and classification].

Salivary gland carcinomas comprise a rare group of malignant tumors which are difficult to diagnose and treat due to their histopathologic diversity, variable clinical course and anatomic location, particularly with respect to the facial nerve. The present paper summarizes important features of these tumors, including recent advances in their management, i.e., diagnosis, surgery of the primary tumor, neck dissection, radiation therapy, and updates risk factors, criteria of malignancy, and prognostic variables, taking into account the relevant literature. Additionally, the present paper highlights briefly the survival rates of patients suffering from salivary gland carcinomas. The present overview is divided into two parts: the first is focused on epidemiology, etiology, criteria of malignancy, prognostic factors, and tumor classification, while part II discusses the diagnosis and therapy of salivary gland carcinomas.

Carcinoma↗
PubMed2005

[Salivary gland carcinomas Part II. Diagnosis and therapy].

Salivary gland carcinomas comprise a rare group of malignant tumors which are difficult to diagnose and treat due to their histopathologic diversity, variable clinical course and anatomic location, particularly with respect to the facial nerve. The present paper summarizes important features of these tumors, including recent advances in their management, i.e., diagnosis, surgery of the primary tumor, neck dissection, radiation therapy, and updates risk factors, criteria of malignancy, and prognostic variables, taking into account the relevant literature. Additionally, the present paper highlights briefly the survival rates of patients suffering from salivary gland carcinomas. The present overview is divided into two parts: the first is focused on epidemiology, etiology, criteria of malignancy, prognostic factors, and tumor classification, while part II discusses the diagnosis and therapy of salivary gland carcinomas.

Humans↗
PubMed2005

Influence of hospital volume on local recurrence and survival in a population sample of rectal cancer patients.

AIMS: To investigate the role of hospital volume and individual hospitals on long term outcomes (local recurrence and survival) of rectal cancer patients. METHODS: One thousand thirty-eight patients with rectal cancer were diagnosed between 1996 and 1998. From these, we analysed 884 patients with a resected invasive primary rectal cancer. Median follow-up was 5.7 years. The impact of hospital volume (<10, 10-30 and >30 rectal cancer patients annually) on local recurrence and survival was examined in a Cox model. Differences between the four largest clinics in the high volume group were also investigated. RESULTS: In the multivariate model predicting survival the following variables were significant: UICC stage, grade, age, local recurrence, and (neo-) adjuvant therapy treatment. In the multivariate model predicting local recurrence UICC stage, tumour localisation, and neoadjuvant therapy treatment were significant variables. Hospital volume was not a significant factor for survival or local recurrence. Within the high volume category one hospital showed significantly worse local recurrence rates than all other hospitals, but no survival difference could be seen between the four largest hospitals of the high volume group. CONCLUSIONS: This analysis of a rectal cancer population found that hospital volume did not determine survival or local recurrence. Detailed clinical data with long term follow-up from cancer registries are vital to demonstrate the quality of routine care.

Aged↗
PubMed2003

The process of metastasisation for breast cancer.

To investigate the process of metastasis, primary clinical data and disease events such as metastases, local recurrence and survival (median follow-up 9.4 years) from the Munich Cancer Registry from 1978 to 1996 were analysed. Since metastases, even from small tumours, may be initiated before the diagnosis of the primary tumour, the growth of the primary tumour and metastasisation may be two autonomous processes. In our data, survival following metastases was almost unrelated to primary tumour size. However, the number of M1 cases and the time to metastasisation depended on the tumour diameter at diagnosis. The time from initiation of metastases to its diagnosis was estimated as 5.8 years. The growth of metastases was almost homogeneous. However, the growth time following metastasisation-depending on the metastases-free time, receptor status and histological grade-only varied by approximately a factor of 2. Local recurrence, above all, was an indicator of metastases. Furthermore, local recurrence may also have the potential to metastasise. Excess mortality due to local recurrence was estimated up to 9.3 years after diagnosis. Our hypothesised metastases model illustrates the importance of early detection, the concept of breast-conserving therapy and additional metastases from local recurrence. It highlights the benefits of optimal local therapy of the primary tumour and the limitations of systemic therapy. It also questions the use of axilla dissection and lymph node irradiation. Its generalisation to solid tumours may help to clarify many of the current controversial debates.

Breast Neoplasms↗
PubMed2003

Comparison of breast and rectal cancer patients' quality of life: results of a four year prospective field study.

This paper compares quality of life in breast and rectal cancer patients. The Munich Cancer Registry records clinical details of all cancer patients in the region. Over a 2-year period, cooperating clinicians recruited patients who were sent quality of life questionnaires, including the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire - C30 over 4 years. Breast cancer patients were compared to both male and female rectal cancer patients. A total of 1315 patients returned questionnaires (988 breast cancer, 327 rectal cancer). More breast cancer patients were under 70 years old, received adjuvant therapy, had a good prognosis, took medication and rated psychological support as important. Breast cancer patients reported poorer quality of life than rectal cancer patients in more than half the variables. In particular, they suffered significantly worse emotional functioning, fatigue, pain and sleeplessness. Female rectal cancer patients did not suffer the same problems. Both age groups and those with or without adjuvant therapy indicated the same trend, with breast cancer patients reporting lower scores. Breast cancer patients, despite better prognoses, appear to suffer more psychological problems than rectal cancer patients. Gender, age and therapy did not seem to explain these differences. The negative public perception of breast cancer may play a role.

Adult↗
PubMed2003

Fat distribution is altered in HIV-infected men without clinical evidence of the HIV lipodystrophy syndrome.

OBJECTIVE: To determine if fat distribution is altered in HIV-infected men without clinical evidence of lipodystrophy. METHODS: In a cross-sectional design, 14 protease inhibitor (PI)-treated men with lipodystrophy and 12 PI-treated and five PI-naive men without clinical evidence of lipodystrophy underwent body composition and fat distribution analysis by dual-energy X-ray absorptiometry and computed tomography. Their fat distribution was compared to 43 uninfected male controls matched for age and BMI. RESULTS: The percent of body fat in the trunk of men with HIV lipodystrophy was significantly greater compared to both HIV-infected and healthy controls. The percentage of body fat in the extremities was significantly lower in men with HIV lipodystrophy compared to both HIV-infected and healthy controls. HIV-infected men without clinical evidence of lipodystrophy also had a significantly greater percentage of total body fat in the trunk and a significantly lower percent of body fat in the extremities compared to healthy controls. Among the HIV-infected men, age was an independent predictor of truncal and extremity adiposity. CONCLUSION: This study suggests that a continuum of change is present in the adipose organ of HIV-infected men on antiretroviral therapy. Physical examination alone can miss significant changes in body fat distribution in HIV-infected patients.

Abdomen↗
PubMed2002

Moderate progress for ovarian cancer in the last 20 years: prolongation of survival, but no improvement in the cure rate.

Although ovarian cancer treatment has advanced in the last 20 years, long-term survival remains stable. The purpose of this study was to determine whether survival has improved in line with treatment advances in a population-based prospective cohort of ovarian cancer patients (1978-1997, with a follow-up through to 2000). The 10-year overall survival rate for cancer patients was similar before and after 1988: 32.2% (n=1661) and 34.4% (n=2089). For patients after 1988, a 12-month prolongation of median survival was observed. In terms of stage according to the International Federation of Gynecology and Obstetrics (FIGO), only FIGO I and FIGO II patients showed, in addition to a prolongation in survival, an absolute improvement of 12.9 and 12.6% after 5 years and of 13.2 and 8.6% after 10 years. This hardly affected the survival of the total sample. For the most frequent stage FIGO III patients and for FIGO IV patients, a prolongation in survival time, but no improvement in survival rate, was seen after five or 10 years. The progress in FIGO I and II patients may be due to more accurate staging. More effective chemotherapy may also explain some of the improvement. The prolongation in FIGO-stages III-IV may be due to more radical surgery. Patient selection criteria, not only the treatment modalities, may be responsible for the superior results reported in clinical trials. Cancer registries are important for evaluating the quality of healthcare delivery.

Aged↗
PubMed2002

[Clinical and epidemiological data of patients with malignomas of the head and neck].

BACKGROUND: The present study describes clinical and epidemiological data of patients with malignomas of the head and neck documented in the Munich Cancer Register. PATIENTS AND METHODS: Data of head and neck cancer patients treated at four departments of head and neck surgery and one of oral-maxillo-facial surgery in the area of Munich from 1978 up to now are reported. RESULTS: Incidence and mortality as a function of age, sex, and tumor localization are described in comparison to clinical and epidemiological data as specified in tumor registers of the Saarland and the USA. Moreover, TNM stages, survival, recurrence, and metastasis rates are presented. CONCLUSION: Based on the documentation of the Munich Cancer Register our study is the first to present a detailed description of clinical and epidemiological data of patients suffering from head and neck malignomas.

Adult↗
PubMed1998

Lipid levels in anorexia nervosa.

OBJECTIVE: Anorexia nervosa is a chronic disorder characterized by the patient's refusal to maintain body weight and a myriad of medical complications. Two frequently cited and poorly understood complications are hypercholesterolemia and hypercarotenemia. We therefore measured fasting cholesterol and beta-carotene levels in a cohort of moderately severe anorectics. METHOD: All subjects were female and met DSM-IV criteria for anorexia nervosa. Lipid profiles and beta-carotene levels were determined in 23 female anorexics. RESULTS: The mean total cholesterol for this group of anorectics was 179.3 mg/dl. Low-density lipoprotein values (LDL) ranged from 47 to 173, with a mean of 104.1 mg/dl. The mean high-density lipoprotein value (HDL) was 51.5 mg/dl. Beta-carotene levels were all normal. DISCUSSION: We conclude that total and LDL cholesterol in anorexia are well within the range of normal, and HDL levels are favorably high. Further, hypercarotenemia was not associated with anorexia nervosa.

Adolescent↗
PubMed1996

Design elements of a telemedical medical record.

Computerized Patient Records are becoming telemedical and multimedia documents. They should accompany the patients their whole lifetime and collect data from many different sites. Special requirements are arising to fulfill these demands. A prototype of such a system was designed and implemented at the university hospital in Grosshadern, Germany to show its feasibility, discuss the design elements and demonstrate its capabilities. A Flexible data model, interpretable contents, open communication structures and physical compilation are the cornerstones of this approach that allows communication via Internet or Smart cards.

Computer Communication Networks↗
PubMed1987

Xanthogranulomatosis in an adult: lipid analysis of xanthomas and plasma.

Xanthomatosis in the absence of hyperlipidemia is unusual but has been associated with compositional abnormalities of lipoprotein particles. An adult who developed juvenile xanthogranulomatosis in association with oral contraceptive ingestion is reported. Plasma lipids and lipoprotein electrophoresis were normal, as in a few other patients reported with this disorder. However, analysis of cutaneous xanthoma and plasma by thin-layer and gas-liquid chromatography revealed that cholesterol was the principal lipid in xanthoma and that there were no unusual sterols in plasma or tissue. Possible mechanisms of xanthoma formation are discussed. Thus juvenile xanthogranulomatosis should be considered in adults with normolipemic xanthomatosis.

Adult↗
PubMed1985

Plasma decay of chylomicron remnants is not affected by heparin-stimulated plasma lipolytic activity in normal fasting man.

In an earlier study it was shown that retinyl palmitate appeared to be a satisfactory label for the core of chylomicrons and their remnants. When chylomicrons were endogenously labeled with retinyl palmitate and pulse-injected into healthy donors, retinyl palmitate was cleared from plasma by a first order process. Its fractional decay constant was very similar to the fractional catabolic rate of VLDL triglycerides, a lipoprotein lipase-dependent process, and 2-3 times slower than hepatic chylomicron remnant uptake in experimental animals. We, therefore, investigated whether plasma clearance of retinyl palmitate-labeled chylomicrons is accelerated by enhanced plasma triglyceride hydrolysis produced by heparin administration. Five healthy subjects took retinyl palmitate by mouth and 5-6 hr later two units of plasma were obtained by plasma-pheresis. After storage for 42 hr, the units were pooled and separated into two equal volumes. The first half was injected into the donor and plasma retinyl palmitate and chylomicron triglyceride were measured for 3.5 hr (control study). Heparin was then given intravenously as a bolus followed by an infusion for 7 hr. A second retinyl palmitate clearance (postheparin study) was performed during the heparin infusion. Plasma lipolytic activity and retinyl palmitate and chylomicron triglyceride concentrations were measured serially. Total plasma lipolytic activity and hepatic triglyceride lipase activity were increased approximately 500-fold during postheparin studies, enhancing triglyceride decay 2.5- to 3-fold. Retinyl palmitate plasma decay, however, was unaffected. Retinyl palmitate plasma decay was a biexponential concentration-dependent function in eighty of ten pre- and postheparin studies with the first, rapid exponential accounting for 90 +/- 4% of total plasma retinyl palmitate decay.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1978

Transcriptional capacity of rat liver nuclei and of isolated chromatin at different ammonium sulphate concentrations.

The transcription of freshly prepared nuclei and lysates from rat liver is stimulated by exogenous RNA polymerase B from calf thymus to an insignificant extent only. This also holds for chromatin isolated from nuclei lysates by separation on a Sepharose 4 B column. After removal of histone H1 by pretreatment with 0.2 M ammonium sulphate no further stimulation by added RNA polymerase has been found. If, however, the incubation time was extended, or the nuclei had been kept frozen at -20 degrees C for some time before use, a significant increase in RNA synthesis by the added RNA polymerase was obtained. In the freshly prepared nuclei as well as in the undamaged chromatin the template capacity was highly restricted. This can be seen from the fact that after pretreatment of the chromatin with 0.4 M ammonium sulphate the RNA synthesis was stimulated about 13fold.

Ammonium Sulfate↗