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T Ebert

Publications and source records attributed to T Ebert.

At least 19 recordsLinked to original sources
PubMed2006

[Nutrition, lifestyle, physical activity, and supportive care during chemotherapeutic treatment].

With improvements in cancer survival rates, more patients with cancer are living longer and the influence of nutrition, lifestyle, physical activity as well as supportive care during and after chemotherapy is of increasing interest. In several malignancies smoking cessation increases cancer survival. Similar effects are expected by healthy nutrition. Regular physical activity of cancer patients reduces drug interactions of chemotherapy, decreases the number of comorbid conditions, and helps patients maintain independence as long as possible. For supportive care during chemotherapy the 5-HT3 receptor antagonists are more effective for the prevention of chemotherapy-induced nausea and vomiting. There are several colony-stimulating factors (e.g. GCSF, erythropoietin) for hematopoietic recovery post-chemotherapy. Altogether supportive care of chemotherapy reduces toxicity and increases efficacy.

Drug Therapy↗
PubMed2006

[Local recurrence of prostate cancer: hormone therapy].

BACKGROUND: The majority of patients receive HT after biochemical progression despite primary therapy of prostate cancer with curative intent. It is difficult to differentiate at a low rise in PSA level, e.g., <or=1 ng/ml, between local or systemic recurrence. MATERIAL AND METHODS: The PSA doubling time (DT) is the most reliable surrogate parameter to decide if HT should be initiated. In practice, however, the trigger PSA is used instead. The latter is closely related to the timing of HT. A high PSA is a contraindication for local salvage therapy. Intermittent HT is apparently as effective as continuous HT and shortens the time of HT exposure. RESULTS: Traditional HT employs a LHRH agonist, however, the side effect profile is a disadvantage due to the long duration of this treatment, e.g., sarcopenia, osteopenia, or even cognitive impairment. The alternative is nontraditional HT: nonsteroidal antiandrogen (AA) alone such as bicalutamide 150 mg or peripheral androgen blockade (AA plus 5alpha-reductase inhibitor). CONCLUSION: Even after a long duration of the latter HT the side effects are less pronounced (gynecomastia) and treatable. Particularly in patients with high-risk primary tumors [Gleason score 7(4+3)-10 or an initially high PSA], nontraditional HT may be followed by secondary HT.

Antineoplastic Agents, Hormonal↗
PubMed2005

[Lymph node dissection in patients with renal cell carcinoma].

The role of lymph node dissection in renal cell carcinoma has been controversial for decades. However, the results of the only prospective randomised study concerning this issue (EORTC 30881) are preliminary. Retrospective analyses were not able to demonstrate a diagnostic or therapeutic benefit of an extended lymph node dissection. Suspicious lymph nodes (imaging, palpation) should be excised during nephrectomy.

Carcinoma, Renal Cell↗
PubMed2005

[When is aftercare useful in renal cell cancer?].

Diagnosis of tumor recurrence and of therapy-related side effects as well as psychological support are the main goals of a surveillance program of cancer patients. While the latter may represent a time-consuming effort, most diagnostic procedures are expensive. Whether we can efficiently detect tumor recurrence in renal cell carcinoma depends on various parameters of the recurrent disease (e.g., frequency, localization, or therapeutic options). Available data lend support to "lean" follow-up strategies in patients with renal cell carcinoma.

Aftercare↗
PubMed2005

The current status of therapy for symptomatic late-onset hypogonadism with transdermal testosterone gel.

For over 50 years, testosterone therapy has been used for the treatment of hypogonadism. In recent years, there has been an increase in the use of testosterone therapy for men with late-onset hypogonadism, as more convenient and effective modes of application are developed. Testosterone therapy in these men can significantly improve their sense of well-being, and lead to increases in muscle and bone mass, upper body strength, virility and libido [Gruenewald, Matsumoto. J Am Geriatr Soc 2003;51:101; Morales. Aging Male 2004; in press]. However, ensuring that optimal testosterone therapy is achieved in men with hypogonadism remains challenging. Oral delivery of unmodified testosterone is not possible, due to rapid first-pass metabolism and its short half-life. Therefore, different derivatives and formulations of testosterone have been developed to enhance potency, prolong duration of action or improve bioavailability. In addition, several different routes of administration have now been evaluated, including intramuscular injections, oral formulations, transdermal patches, transbuccal systems and transdermal testosterone gel. Despite the broad range of testosterone therapy on offer, each form has its benefits and limitations, and some will suit one patient more than another. An important concern among clinicians is that testosterone therapy may cause or promote prostate cancer. While current evidence supports the safety of testosterone therapy, androgens are growth factors for pre-existing prostate cancer. Therefore, before therapy is initiated, careful digital rectal examination and determination of prostate-specific antigen (PSA) in serum should be performed, in order to exclude evident or suspected prostate cancer. The first 3-6 months after initiating testosterone therapy is the most critical time for monitoring effects on the prostate. Therefore, it is important to monitor PSA levels every 3 months for the first year of treatment; thereafter, regular monitoring (mostly for prostate safety but also for cardiovascular and haematological safety) during therapy is mandatory.

Administration, Cutaneous↗
PubMed2004

Clinical experiences with testosterone therapy: prostate safety.

Due to a decrease in Leydig cell function, a considerable proportion of men over 50 years of age will develop hypogonadism. Consequently, loss of libido and several other testosterone-dependent symptoms may become evident. When decreased levels of biologically available testosterone are found, and corresponding symptoms are present, these men could be eligible for testosterone substitution therapy. Testosterone treatment in testosterone-deprived men has been shown to improve general well-being, osteoporosis, muscle atrophy, libido and--if present--anemia. Despite these positive effects, testosterone treatment has to be performed with caution. Although it has not been proven that elevation of the serum testosterone level to the normal range results in a greater risk of developing prostate cancer, the effects of testosterone on a prostate cancer already present are well established. Several studies have demonstrated that testosterone treatment does not result in a significant increase in serum levels of prostate-specific antigen (PSA) or prostate volume. The long-term effects, however, are currently unknown. For these reasons, testosterone treatment should be performed only when the presence of prostate cancer is unlikely; i.e. when PSA levels are within normal limits and digital rectal examination does not reveal any suspicious findings. These examinations may still miss some small prostate cancers that could be promoted by testosterone treatment. The determination of PSA levels under testosterone treatment is necessary every 3 months, at least for the first year. Steadily rising PSA levels require immediate cessation of testosterone administration and the initiation of further diagnostic procedures (prostate biopsy), to rule out prostate cancer.

Androgens↗
PubMed2003

[Treatment of trochanteric fractures with the gamma nail].

The osteosynthesis of trochanteric fractures requires a minimal invasive technique to guarantee fully weight bearing and early rehabilitation in elderly patients. In this retrospective study we want to prove if the gamma nail meets all requirements and if the results improved after initiation of the new instrumentarium and standardization of the operative technique. From January 1992 until April 2000 we treated 387 patients with a gamma nail. The average age was 79.4 years. We used the new instrumentarium suitable for radiography since June 1996, the operative technique was standardized since the same time. The evaluation occurred on the basis of clinical and radiological findings included analysis of complications. We've seen intraoperative problems in 29% before June 1996, this rate could be reduced to 9%. General postoperative complications presented in equal frequency. After improvement of the technique dislocations of the neck screw and relevant sinking of the fractures were more rarely. The rate of reoperations after complications of the implant was 8% in both groups. In consideration of technical standards the postoperative full weight bearing and early mobilisation is possible even in old patients.

Adolescent↗
PubMed2002

FHIT expression in clear cell renal carcinomas: versatility of protein levels and correlation with survival.

Clear cell renal cell carcinomas (RCCs) are characterized by a deletion of chromosome 3p, which might result in the inactivation of the FHIT (fragile histidine triad) gene, a putative tumour suppressor gene. To explore the relevance of FHIT aberrations for tumour progression and prognosis in clear cell RCCs, FHIT protein expression was analysed in formalin-fixed tissue from 149 clear cell RCCs by immunohistochemistry. FHIT protein expression was found to be markedly reduced in all RCCs, when compared with adjacent non-neoplastic tubule epithelia. Although remaining below the FHIT levels of normal tubule epithelia, a significant increase of FHIT expression became evident from well (G1) to poorly (G3) differentiated clear cell RCCs (p=0.0001) and from low (pT1) to advanced (pT3) tumour stages (p=0.001). The log-rank test demonstrated a significant inverse correlation (p=0.0074) between FHIT expression and tumour aggressiveness as indicated by patient survival. Cox regression analysis revealed that FHIT expression is an independent prognostic parameter (p=0.0139) in clear cell RCCs. In conclusion, clear cell RCCs show a marked reduction of FHIT protein expression when compared with their putative cells of origin. In contrast to other tumour types, however, loss of FHIT protein expression is significantly less pronounced in poorly differentiated RCCs or advanced tumour stages. This versatility of FHIT expression during tumour progression suggests a role for reversible mechanisms of FHIT inactivation during the initiation and progression of clear cell RCCs.

Acid Anhydride Hydrolases↗
PubMed2001

Nutrition and prostate cancer.

Nutrition is apparently a major risk factor for the development and progression of prostate cancer. Based on experimental studies and epidemiologic data mainly from case-control studies or cohort studies, there is strong evidence that reduction of the total energy consumption, a diet comprising less than 30% fat, and increased intake of phytoestrogens, vitamins D and E and selenium could yield a decreased prostate cancer incidence. Furthermore, some of these measures appear to have antitumoral capacity even in the presence of the disease. These observations have provided a rationale to forward large prospective trials on dietary interventions to prove the efficacy of the concept and further delineate the correlation between nutritional compounds and prostate cancer risk. These chemoprevention trials are either aiming a reduction prostate cancer incidence or a decrease in tumor progression. Depending on the study design, large numbers of individuals need to be enrolled and long follow-up intervals are required thus making such trials highly complex and cost-intensive. However, regarding the potential relevance of chemoprevention on public health, further efforts to identify nutritional factors affecting prostate cancer growth are warranted.

Carotenoids↗
PubMed2001

Simultaneous diagnosis of a metanephric adenoma and a clear cell carcinoma of the contralateral kidney.

Metanephric adenoma of the kidney is a rare, newly recognized entity of a unique benign renal tumor. Clinically, pain, hematuria and palpable mass are the most common presenting signs. Females predominate by well over 2:1. A higher incidence of polycythemia is often found in these patients. Only a few cases of this type of adenoma have been reported in the literature. We report on a 78-year-old female patient with a metanephric adenoma of the left kidney, which showed typical clinical, radiologic, microscopic and immunohistochemical findings. A clear cell carcinoma of the contralateral kidney was also discovered and treated.

Adenocarcinoma, Clear Cell↗
PubMed2000

[Clinical value of scintigraphy for gastrointestinal bleeding. Experiences in a large community hospital].

BACKGROUND AND OBJECTIVE: In the majority of cases of gastrointestinal bleeding the site and cause can be determined by gastroscope. If this is unsuccessful, radiological and nuclear-medical tests are available. This study was undertaken to determine the value of scintigraphy in diagnosing of the site of gastrointestinal bleeding. PATIENTS AND METHODS: The data on 155 patients who, between 1984 and 1988, had undergone 161 scintigraphies (with 99mTc-labelled erythrocytes, 5 with 99mTc-Sn colloid) were retrospectively analysed. The results were compared with other diagnostic tests that had been performed, with the definitive diagnosis and, where applicable, the findings at surgery. RESULTS: 78 scintigrams (47%) provided positive results. The site of bleeding had been demonstrated ca. 20 hours after the diagnostic studies had begun. In 47 of the cases the diagnosis was confirmed by additional tests. The intestine was the most common site of bleeding. Localization of the source of bleeding by scintigraphy and other diagnostic tests succeeded in 34 cases, with a 82% concordance between the tests. No bleeding was demonstrated in 88 scintigrams (53%), including all those done with Sn-colloid. In 13 cases the final diagnosis suggested that there had been no previous bleeding and in 43 cases the source of bleeding could not be determined. In 32 scintigraphically negative cases the source of bleeding was demonstrated by other tests. But only 2 of the 13 angiograms and none of the 33 double-contrast studies of the small intestine gave positive results. Among the total number of cases in which bleeding was demonstrated, scintigraphy had a sensitivity of 71%. CONCLUSION: Because of the long duration of observation, scintigraphy with 99mTc-labelled erythrocytes proved superior to other diagnostic tests in the demonstration of the bleeding. By localizing the source of bleeding in a definite part of the gastrointestinal tract, scintigraphy points the way to choosing other diagnostic methods or treatment. If the initial endoscopy has failed, scintigraphy, a method of low invasiveness, should be included when further tests are planned.

Angiography↗
PubMed2000

Influence of cardiac output on dexmedetomidine pharmacokinetics.

Dexmedetomidine, a highly selective alpha(2)-adrenoceptor agonist, reduces the requirements for anesthetic, analgesic, sedative, and hypnotic drugs. Dexmedetomidine pharmacokinetics were characterized in healthy subjects after intravenous administration by means of a computer-controlled infusion pump. A series of seven stepwise increasing pseudo-steady-state plasma concentrations were targeted. The influence of cardiac output on the pharmacokinetics was investigated by use of a compartmental modeling approach in which the elimination clearance was characterized as being either cardiac output independent or dependent. At dexmedetomidine concentrations of 0, 0.6, and 1.2 ng/mL, mean (SD) estimated cardiac outputs were 5. 6 (0.85), 5.1 (0.67), and 4.5 (0.83) L/min, and mean (SD) clearances were 40 (10), 38 (9.0), and 35 (8.5) L/h, respectively. Dexmedetomidine V(SS) and elimination half-life were 72 (19) L and 1. 9 (0.62) h, respectively. The approximately 3 to 19% decrease in cardiac output observed within the anticipated therapeutic range of 0.3 to 1.2 ng/mL was similar to that observed for clonidine. The decrease in cardiac output with increasing plasma concentrations of dexmedetomidine resulted in a corresponding decrease in drug elimination clearance of < or =12% within the therapeutic range; however, this decrease in dexmedetomidine clearance is likely not clinically relevant.

Adolescent↗
PubMed2000

p53 immunohistochemistry as a prognostic marker in bladder cancer. Playground for urology scientists?

OBJECTIVES: Anomalies of the p53 tumor suppressor gene have been reported for a variety of different tumor types. Also in urothelial cancer accumulation of the P53 protein has been linked with an unfavorable prognosis of the patients. Despite the growing number of publications confusion remains because key questions regarding p53 accumulation in bladder cancer are still unanswered. The objective of this manuscript was to review all published literature on the association of p53 accumulation and prognosis of patients with bladder cancer. Furthermore, putative reasons for the conflicting results should be defined as a basis for future research. METHODS: The entry criteria for the analysis were met by 43 trials comprising 3,764 patients out of 138 publications found through Medline search. RESULTS: Comparison between the trials yielded considerable differences obviously due to technical aspects, e.g. the selection of the antibody and the use of different cut-off values, study design and patient selection. CONCLUSIONS: From this analysis it becomes evident that further retrospective investigations will not contribute to the solution of the problem and thus are obsolete. There is an obvious need for standardization of the assay procedure and the assessment of the specimens as well as for the initiation of a prospective multicenter trial to provide definite answers.

Carcinoma, Transitional Cell↗
PubMed1999

[Current status and perspectives of shoulder replacement].

Basis of the modern shoulder implants is the Neer II-system, a non constrained total shoulder prosthesis with conforming radii of curvature and improved protection against dislocation. The second generation of shoulder prosthesis is based on the geometric shaft design of the Neer II prosthesis and offers not only a variety of modular head- and shaft-sizes but also through different radii a physiologic rotation-translation-mechanism. The third generation of humeral head prosthesis carries the concept of an anatomic reconstruction one step further and enables the surgeon to adjust the inclination and the eccentric offset of the humeral head to restore the centre of rotation. The latest development in shoulder arthroplasty are humeral head prosthesis with a fully variable 3-dimensional modularity to independently adjust the prosthetic head position regardless of the individual shaft geometry. This achieves a 3-dimensional adaptability of the prosthetic head about the stem axis in the coronary and in the sagittal plane. Besides of the humeral shaft prosthesis an alternative concept of shoulder joint replacement is established - the replacement of the humeral head articular surface. A hemispheric surface prosthesis - cup arthroplasty - is cemented onto the residual humeral head, which eliminates the obligatory humeral head resection and the reaming of the medullary canal. Bipolar shoulder prosthesis are humeral shaft prosthesis with a bi-rotational head system. Their indication is limited to pre-existing lesions of the rotator cuff and/or the glenoid surface. The inverse total shoulder prosthesis reverses the articular surface morphology of the humeral head and the glenoid. The hemispheric glenoid component serves as the centre of rotation for the concave epiphyseal proximal humerus component. This implant is especially used in cases of massive rotator cuff deficiencies. The role of shoulder prosthesis in treating acute humeral head fractures needs special consideration. A fracture prosthesis has to restore the exact length of the humerus, the centre of rotation, and the anatomical retroversion. Positioning of the tubercula and their adequate osteosynthesis is most critical and fundamental to ensure a correct healing process. A failed consolidation of the tubercula does not lead to a satisfying result. The shoulder joint replacement can be sufficiently fixated in cemented, cementless or hybrid techniques. Today several component design variations of cemented glenoid implants exist. Their main distinction is the fixation system which can be divided into two main groups - the keel - and the peg-shaped glenoid components. The peg-shaped anchorage system shall guarantee a greater stability against shear-forces. Cementless glenoid components consist of a polyethylene inlay and a surface treated metal-back with an integrated fixation system. These fixation systems are object of intensive biomechanical research and range from conventional screw fixation to specialised cone systems and self-cutting cage-screw-systems. The critical area of cementless glenoid components is the transition zone of the PE-inlay and the metal-back because of high force development. The question of implanting a hemi- or total shoulder prosthesis is answered by the morphologic changes of the glenoid articular surface, which includes the size of the subchondral defect and the underlying etiology of the shoulder joint disease, and the age of the patient. Preoperative planning must consist of an adequate radiologic work-up - X-ray, CT or MRI - to accurately assess the glenoid morphology. G. Walch categorised the different glenoid lesions and developed a very important classification of possible glenoid deformations. To compare and evaluate the operative results one must consider the different shoulder prosthesis and the discrepancies between a hemi- and a total shoulder prosthetic replacement. Looking at the loosening and survival rate of the implant the results are

Equipment Failure Analysis↗
PubMed1999

[Reconstructive surgery of the efferent urinary tract in pelvic exenteration of gynecological tumors].

In locally advanced or recurrent tumors of the female genital tract anterior or total exenteration may be mandatory in case of tumor invasion into the lower urinary tract or if a second course of radiation therapy is not feasible. The management of resection and reconstruction of the affected lower urinary tract has to be well integrated into the gynecological therapeutic concept. In 11/32 patients the reconstruction of the partially resected lower urinary tract was feasible with preservation of a functionally intact urinary bladder. Urinary diversion following pelvic exenteration was achieved in 13/17 patients with a continent urinary reservoir and in 4/17 patients with an ileal conduit. Operative reinterventions were needed only in patients with continent urinary diversion in 5 cases. All these patients had a past history of primary radiation therapy of their gynecological tumor. In the remaining other 11 patients with a history of primary radiation therapy no complications occurred. 9 of 32 patients survived the operative procedure 40.8 (25-57) month with no evidence of recurrent tumor. Continent urinary diversion represents an excellent therapeutic option for replacement of function lost due to exenterative pelvic surgery. Stringent selection of patients is mandatory to consider the presented therapeutic concept a reasonable tool in the management of the described clinical situations.

Adult↗
PubMed1999

Loss of HNF1alpha function in human renal cell carcinoma: frequent mutations in the VHL gene but not the HNF1alpha gene.

Human renal cell carcinoma (RCC) is a common malignant disease of the kidney characterized by dedifferentiation of renal epithelial cells. Our previous experiments showed that most RCCs have a loss of function of the tissue-specific transcription factor hepatocyte nuclear factor (HNF) 1alpha. Detailed analyses of the 10 exons encoding HNF1alpha in 32 human RCCs by single-strand conformation polymorphism analysis and direct DNA sequencing revealed no tumor-associated mutation, whereas with the same probes we frequently found mutations in the von Hippel-Lindau tumor suppressor gene. No mutation leading to loss of HNF1alpha function was detected by analyzing the integrity of the HNF1alpha transcripts in the RNA derived from RCCs by the protein truncation test. Investigating human RCC cell lines by western blotting and gel retardation assays showed a dramatic loss in the expression of the tissue-specific transcription factor HNF1alpha in eight of 10 cell lines. As the HNF1alpha-related transcription factor HNF1beta was expressed in all these tumor cell lines, the loss of HNF1alpha expression was a specific event and was maintained in RCC cell lines. The loss of HNF1alpha expression in RCC cell lines on the RNA level was confirmed by reverse transcription polymerase chain reaction. We propose that tumor-associated mutations in the HNF1alpha gene do not occur in human RCC and that the loss of function is partially due to a transcriptional inactivation of the HNF1alpha gene.

Adenocarcinoma, Clear Cell↗