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W Becker

Publications and source records attributed to W Becker.

At least 163 records · Page 9Linked to original sources
PubMed1998

[Effectiveness of goiter treatment with L-thyroxine in patients over 40].

AIM: We examined the effect of levothyroxine on thyroid size in elderly patients (an age > 40 y) with diffuse or nodular goitres. METHODS: 76 patients without relevant autonomy were treated with levothyroxine (2 micrograms/kg BW/d) over a period of 6-12 months. The elderly patients with diffuse goitres (group A, n = 33) and nodular goitres (group B, n = 21) were compared to 18-30 year old respective control groups (group C, n = 13, group D, n = 9). Laboratory parameters and ultrasonic determined goitre volumes were documented before levothyroxine treatment and after 6-12 months, respectively. All measured thyroid volume reductions were referred to the total goitre size. RESULTS: After 6-12 months levothyroxine treatment a significant thyroid reduction was observed in group A (14.8%, p < 0.001), group C (16.0%, p < 0.05) and in group D (19.8%, p < 0.05), whereas in group B thyroid volume was nearly unchanged (4.5%). The result of group B differed from that of group D (p < 0.05). CONCLUSION: These results suggest that levothyroxine can reduce diffuse goitres in elderly patients (group A), whereas in nodular goitres of elderly patients (group B) only a further thyroid growth can be provided.

Adult↗
PubMed1998

Crown lengthening: the periodontal-restorative connection.

Crown lengthening procedures are based on biologic principles that can be determinants for successful treatment. These procedures are fixed on an understanding of the biologic width. A few of the indications for crown lengthening are caries beneath the gingival margin, fractured teeth with insufficient clinical crown exposure, and teeth with excessive occlusal or incisal wear. This article describes flap designs, the use of a new bur probe for precise measurement of clinical crown exposure, and suturing methods for flap stabilization. Clinical documentation of patients with various clinical situations requiring crown lengthening is presented.

Crown Lengthening↗
PubMed1998

Clinical value of immunoscintigraphy in patients with fever of unknown origin.

UNLABELLED: The aim of our study was to evaluate the clinical value of immunoscintigraphy with the monoclonal antibody 99mTc-BW 250/183 in patients with fever of unknown origin (FUO). The antibody BW 250/183 is an immunoglobulin G1 subtype that binds to the antigen NCA-95, which is expressed on the cell membrane surface of granulocytes. METHODS: We studied 51 patients who were referred with the diagnosis of FUO. Thirty-five percent of the patients suffered from infection, 17% had autoimmune diseases, 14% had neoplasms and 8% had other diseases. The remaining 28% of the patients did not have a diagnosis. Planar imaging was performed in all patients, and 19 patients underwent SPECT. In our analysis, both cold and hot spots were considered diagnostic. RESULTS: Pyogenic infections were visualized correctly in 13 foci. The diagnosis of endocarditis (n = 4) could be determined only by SPECT. False-negative results were found in 4 patients and false-positive uptake was seen in 2 patients. No false-positive uptake or cold spots in the central bone marrow were found in patients with viral, granulomatous and autoimmune diseases or in those patients in whom no FUO cause was found in a 6-mo follow-up. In these patients, a negative scan did not change their diagnostic work-up. Cold spots in the central bone marrow were correctly interpreted in 5 of 6 patients. Sensitivity in detecting pyogenic foci was 73% and specificity was 97%. Positive and negative predictive values were 93% and 87%, respectively. Including areas of decreased uptake in the analysis, sensitivity for detecting an underlying inflammatory or malignant process for FUO was 81 % and specificity was 87%. Positive and negative predictive values were 81% and 87%, respectively. CONCLUSION: Immunoscintigraphy with 99mTc-BW 250/183 in patients with FUO has clinical potential for the diagnosis and exclusion of pyogenic causes of FUO. Metastatic malignant disease and high-grade spondylodiskitis could be diagnosed early in a diagnostic work-up by a characteristic cold spot pattern in the bone marrow. SPECT is indispensible for scintigraphic imaging of endocarditis.

Adult↗
PubMed1998

Rat antigen-induced arthritis: cartilage alterations assessed with iodine-123-antileukoproteinase.

UNLABELLED: Imaging of cartilage alterations was attempted in joints of rats with chronic antigen-induced arthritis (AIA) using the cationic 123I-labeled serine proteinase inhibitor antileukoproteinase (123I-ALP; pI > 10), which selectively accumulates in normal cartilage, presumably through interaction with negatively charged proteoglycans. METHODS: Iodine-123-ALP or 123I-myoglobin, a control protein of comparable size but with different isoelectric point (pI=7.3) was injected intravenously into normal or AIA rats. Joint accumulation was followed by scintigraphy for 14 hr. Tissue radioactivity was assessed by well-counter measurements after dissection. The content of charged molecules in articular cartilage was determined by toluidine blue staining; the degree of joint destruction was assessed in parallel by x-ray, ex vivo MRI and histopathology. RESULTS: In intact articular cartilage, ALP accumulated to a significantly higher degree than myoglobin. This preferential accumulation was lost in rats with chronic AIA. The target-to-background ratio for 123I-ALP negatively correlated with the loss of toluidine blue staining in cartilage, which documents depletion of charged matrix molecules (r=-0.92, p < 0.01 at 4 hr; r=-0.97, p < 0.01 at 13 hr). ALP scintigraphy was sensitive in detecting cartilage alterations, even though the degree of joint destruction and inflammatory infiltration was mild, as demonstrated by x-ray, MRI and histopathology. CONCLUSION: In rat AIA, loss of ALP accumulation appears to document proteoglycan depletion in mildly altered arthritic cartilage. ALP scintigraphy may represent a functional assay for early, premorphological cartilage alterations in human arthritis as well.

Animals↗
PubMed1998

Arthroscintigraphy in suspected rotator cuff rupture.

AIM: In order to evaluate the diagnostic efficiency of arthroscintigraphy in suspected rotator cuff ruptures this new imaging procedure was performed 20 times in 17 patients with clinical signs of a rotator cuff lesion. The scintigraphic results were compared with sonography (n = 20), contrast arthrography (n = 20) and arthroscopy (n = 10) of the shoulder joint. METHODS: After performing a standard bone scintigraphy with intravenous application of 300 MBq 99m-Tc-methylene diphosphonate (MDP) for landmarking of the shoulder region arthroscintigraphy was performed after an intraarticular injection of 99m-Tc microcolloid (ALBU-RES 400 MicroCi/5 ml). The application was performed either in direct combination with contrast arthrography (n = 10) or ultrasound conducted mixed with a local anesthetic (n = 10). Findings at arthroscopical surgery (n = 10) were used as the gold standard. RESULTS: In case of complete rotator cuff rupture (n = 5), arthroscintigraphy and radiographic arthrography were identical in 5/5. In one patient with advanced degenerative alterations of the shoulder joint radiographic arthrography incorrectly showed a complete rupture which was not seen by arthroscintigraphy and endoscopy. In 3 patients with incomplete rupture, 2/3 results were consistent. A difference was seen in one patient with a rotator cuff, that has been already revised in the past and that suffered of capsulitis and calcification. CONCLUSION: Arthroscintigraphy is a sensitive technique for detection of rotator cuff ruptures. Because of the lower viscosity of the active compound, small ruptures can be easily detected, offering additional value over radiographic arthrography and ultrasound, especially for evaluation of incomplete cuff ruptures.

Adult↗
PubMed1997

Anti-carcinoembryonic antigen antibodies versus somatostatin analogs in the detection of metastatic medullary thyroid carcinoma: are carcinoembryonic antigen and somatostatin receptor expression prognostic factors?

BACKGROUND: Surgery is currently the only potentially curative approach in the treatment of medullary thyroid carcinoma (MTC). In many instances however, postsurgically elevated or rising plasma calcitonin and/or carcinoembryonic antigen (CEA) levels indicate persistent metastatic disease, although conventional diagnostic procedures (computed tomography (CT), magnetic resonance imaging (MRI), and invasive venous catheterization) fail to localize the responsible lesions. Recently, anti-CEA antibodies and somatostatin analogs have shown promising results in the staging of MTC. The aim of this study was to compare the sensitivity of both methodologies, especially for the detection of occult MTC, and to assess whether there may be correlations between the scintigraphic behavior and the patients' prognosis. METHODS: A total of 26 patients with medullary thyroid carcinoma were examined at our institution between 1977 and 1996. Ten of them had known disease, 14 had occult metastatic MTC, and 2 were free of disease at the time of presentation. Fourteen patients were investigated with anti-CEA monoclonal antibodies (MAbs) (receiving a total of 35 injections: clones BW431/26, BW431/31, IMACIS, or F023C5, labeled with 99mTc, (111)In or (131)I), and 8 patients were studied with (111)In-labeled octreotide. Two patients received potentially therapeutic doses of (131)I-labeled anti-CEA antibodies. All patients underwent conventional radiologic evaluation (ultrasonography, CT, and MRI) and/or biopsy within 4 weeks. Additional imaging was performed with 99mTc-(V)-DMSA, (131)I-metaiodobenzylguanidine, 201thallium chloride, 99mTc-methylene diphosphate, and/or 18F-fluorodeoxyglucose-positron emission tomography. Clinical follow-up was obtained. RESULTS: All patients with established disease had elevated plasma CEA (range, 6.8-345 ng/mL; calcitonin levels between 92 and 11,497 pg/mL), whereas in 9 of 14 occult cases, levels were < or = 5 ng/mL (range, 0.6-829 ng/mL; calcitonin, 72-2920 pg/mL). In patients with known disease, the overall lesion-based sensitivity was 86% for the anti-CEA MAbs, whereas octreotide was unable to target any tumor in patients with rapidly progressing disease or distant metastases (overall sensitivity, 47%). In all patients with occult MTC, anti-CEA MAbs and octreotide were able to localize at least one lesion (patient-based sensitivity, virtually 100%). In patients with postsurgically persistent hypercalcitoninemia, cervical lymph nodes were identified as the most frequent site of metastases, whereas in patients with occult and slowly progressing disease several years after primary surgery, anti-CEA MAbs and octreotide showed bilateral involvement of mediastinal lymph nodes; however, tumor to nontumor ratios were usually higher with octreotide in these cases. With anti-CEA Mabs, the highest tumor to nontumor ratios were observed in clinically aggressive, rapidly progressing disease. The sensitivity of all other diagnostic modalities was, at < or = 50%, significantly lower. Indication for antitumor effects was observed in a patient receiving 65 mCi of (111)I-labeled F(ab')2 fragments of the clone F023C5. CONCLUSIONS: For the detection of occult MTC, anti-CEA MAbs and octreotide seem to have a sensitivity that is superior to conventional diagnostic modalities, especially also when used in combination. Better detectability with anti-CEA antibodies (which may result in higher CEA expression) seems to be associated with more aggressively growing forms of MTC, whereas somatostatin receptor expression at normal CEA plasma levels and weaker MAb targeting may be associated with a more benign clinical course. This is in accordance with the study of Busnardo et al. (Cancer 1984; 53:278-85), who showed higher CEA serum levels to be associated with a worse prognosis, as well as with the in vitro findings of Reubi et al. (Lab Invest 1991;64:567-73), who demonstrated lower somatostatin receptor expression in less differentiated MTC. Fu

Adult↗
PubMed1997

Improved treatment of medullary thyroid cancer in a nude mouse model by combined radioimmunochemotherapy: doxorubicin potentiates the therapeutic efficacy of radiolabeled antibodies in a radioresistant tumor type.

Whereas in advanced metastatic medullary thyroid cancer (MTC), a variety of chemotherapeutic regimens have achieved only limited success clinically, more recently, radioimmunotherapy (RIT) with 131I-labeled anti-carcinoembryonic antigen (CEA) monoclonal antibodies (MAbs) has shown promising results. The aims of this study were to compare, in an animal model, the therapeutic efficacy of RIT to clinically used "standard" chemotherapeutic regimens and to evaluate whether combination strategies of both modalities may be feasible and may help to improve therapeutic results in this rather radioresistant tumor type. Nude mice, bearing s.c. xenografts of the human MTC cell line, TT, were treated either with the 131I-labeled anti-CEA MAb, F023C5 IgG, or were administered chemotherapeutic regimens that had shown promising results in patients with metastatic MTC (doxorubicin and cisplatinum monotherapy, combinations of both agents, and a 5-fluorouracil/dacarbazine/streptozotocin scheme). Control groups were left untreated or were injected with an irrelevant radiolabeled antibody at equitoxic dose levels. The maximum tolerated dose (MTD) of each agent was determined. Combinations of chemotherapy and RIT were evaluated as well. Toxicity and tumor growth were monitored at weekly intervals. From the chemotherapeutic agents and schemes tested, doxorubicin monotherapy was the most effective; combination therapies did not result in an increased antitumor efficacy, but they did result in more severe toxicity. At equitoxic doses, no significant difference was found between the therapeutic efficacy of doxorubicin and that of RIT. Myelotoxicity was dose limiting with radiolabeled MAbs (MTD, 600 microCi), as well as with chemotherapeutic regimens containing alkylating agents (cisplatinum, dacarbazine, or streptozotocin). At its MTD (200 microg), doxorubicin caused only mild myelotoxicity, and despite signs of cardiac toxicity, gastrointestinal side effects were dose limiting. Accordingly, bone marrow transplantation (BMT) enabled dose intensification with RIT (MTD with BMT, 1100 microCi), which led to further increased antitumor efficacy, whereas BMT was unable to increase the MTD of doxorubicin. Due to the complementarity of toxic side effects but an anticipated synergism of antitumor efficacy, combinations of RIT with doxorubicin were tested. Administrations of 500 microCi of 131I-labeled anti-CEA and, 48 h later, 200 microg of doxorubicin (i.e., 83 and 100% of the respective single-agent MTDs), were the highest doses that did not result in an increased lethality; with bone marrow support, 1000 microCi of 131I-labeled anti-CEA could be combined with 200 microg of doxorubicin (i.e., 90 and 100% of the individual MTDs). Therapeutic results of this combined radioimmunochemotherapy were superior to equitoxic monotherapy with either agent, and indication for synergistic antitumor effects is given. At its respective MTD, radioimmunochemotherapy led to a 36% cure rate if it was given without bone marrow support and to a 85% permanent cure rate if it was given with bone marrow support. The animal model, as presented in this study, seems to be useful for the preclinical testing of therapeutic agents for the systemic treatment of MTC. At equitoxic doses, RIT with radiolabeled anti-CEA antibodies seems to be equally as effective as chemotherapy with doxorubicin. Combination of RIT and doxorubicin chemotherapy seems to have synergistic therapeutic efficacy, which may be due to a radiosensitizing effect of doxorubicin.

Animals↗
PubMed1997

[Antiviral therapy of HIV infection. A practice-based presentation 1997/1998].

New information on the pathogenesis of HIV infection and the possibility of viral quantification have resulted in significant advances in the treatment of this disease. The triple combination of antiviral medications comprising two reverse transcriptase inhibitors and a proteinase inhibitor has brought about an improvement in the quality of life of the patient together with a slowing down of disease progression. For successful patient management, cooperation based on trust and compliance are equally as important as continual observation of the clinical course and monitoring of the viral burden or the T-helper cells.

Antiviral Agents↗
PubMed1997

Visually-guided saccadic eye movements in adolescents at genetic risk for schizophrenia.

Visually-guided saccades of 21 offspring of schizophrenic parents and 21 individually matched controls were compared with regard to the frequency of occurrence of saccadic hypometria and hypermetria, non-fixations, and omissions of target jumps. Target steps ranged from 10 to 60 degrees, and interstimulus intervals averaged 2.5 s; subjects were promised financial reward depending on performance. Recordings were carried out at the subjects' homes. To screen for cognitive abilities and psychopathological behavior, subjects were tested by means of an intelligence scale and a behavioral checklist. With large target steps (40-60 degrees), the high-risk group made significantly more grossly hypometric saccades (gain < or = 0.8) than the control group; responses to small target steps (10-30 degrees) exhibited a similar, albeit statistically not significant, trend. There were no significant differences with regard to the occurrence of hypermetria. Non-fixations scored marginally higher in the high-risks as compared to controls, but this was again not a significant difference. The incidence of omissions of saccades was very low in both groups. The results of the study suggest that subjects at genetic risk for schizophrenia may differ from controls by an increased incidence of conspicuously hypometric saccades. Clearly, this difference is not caused by a deficit of the saccadic motor circuitry proper; comparison to control data obtained with a similar experimental protocol suggests that it probably reflects an impaired internal control of saccades in the presence of distraction and stress. The relevance of saccades as indicators of a possible schizophrenic vulnerability is discussed.

Adolescent↗
PubMed1997

[Clinical relevance of immunoscintigraphy with 99mTc-labelled anti-CEA antigen-binding fragments in the follow-up of patients with colorectal carcinoma. Assessment of surgical resectability with a combination of conventional imaging methods].

BACKGROUND AND OBJECTIVE: Conventional imaging modalities (e.g. ultrasound, computed tomography [CT] and magnetic resonance [MRI]) are used in the routine follow-up of patients with colorectal carcinoma. But they have only limited diagnostic reliability. This study was undertaken to evaluate immunoscintigraphy (IS) with 99mTc-labelled anti-CEA antigen-binding fragments (CEA-Scan) alone or combined with conventional imaging methods. PATIENTS AND METHODS: 22 patients, operated on for colorectal carcinoma and suspected of having a recurrence, underwent scintigraphy with CEA-scan and whole-body single-photon emission computed tomography (SPECT). All results were compared with those by computed tomography (CT) and, in 19 of the patients, with histological findings (surgical specimen or biopsy). The potential influence of the scintigraphic results on surgical management was analysed retrospectively with respect to the preoperative estimate of tumour resectability. RESULTS: Lesion-based sensitivity of IS was 94%, diagnostic accuracy 92%, both being unrelated to the CEA-serum level. When CT and IS were concordant regarding resectability, this estimate was correct in all instances. But in case of discordance the results of IS were verified operatively in 88% of cases. In no patient was there measurable immune reaction with formation of human-mouse-antibodies (HAMA). CONCLUSIONS: These results indicate that IS together with SPECT can achieve reliable and sensitive localisation of tumour lesions. CEA-Scan does not, contrary to other murine antibodies, cause the formation of HAMA. The combination of IS with conventional imaging techniques can improve noninvasively the estimate of surgical resectability.

Adult↗
PubMed1997

Thyroid autonomy with color-coded image-directed Doppler sonography: internal hypervascularization for the recognition of autonomous adenomas.

In a prospective study, we assessed the possibility of recognizing autonomous adenomas of the thyroid with color-coded image-directed Doppler sonography using internal hypervascularization in thyroid nodules for identification. Fifty-three patients with thyroid nodules underwent additional CCDS examination and nuclear scintigraphy (reference). Of 29 patients having autonomous adenomas, 28 patients presented internal hypervascularization in their nodules resulting in a sensitivity of 96% and a specificity was 75%. Interestingly CCDS detected six adenomas in patients showing normal laboratory data (bTSH, TT3, FT4). CCDS could be used to exclude focal adenomas with a negative predictive value of 94%. The positive predictive value for adenoma was 82%.

Adenoma↗
PubMed1997

Enhanced bilateral somatostatin receptor expression in mediastinal lymph nodes ("chimney sign") in occult metastatic medullary thyroid cancer: a typical site of tumour manifestation?

In medullary thyroid cancer (MTC), post-surgically elevated plasma calcitonin and/or carcinoembryonic antigen levels frequently indicate persisting metastatic disease, although conventional diagnostic procedures fail to localize the responsible lesions (occult disease). Somatostatin analogues have been used successfully in disease localization, but recently concerns have been raised that increased thoracic uptake of indium-111 pentetreotide in patients with previous external beam irradiation may represent a false-positive finding, caused by post-irradiation pulmonary fibrosis. We recently examined seven patients with metastatic MTC by somatostatin receptor scintigraphy (six with occult and one with established disease). In four patients, all of whom had stable or slowly rising tumour marker levels over several years, a chimney-like bilateral mediastinal uptake of indium-111 pentetreotide was found. In two patients with persisting hypercalcitonaemia immediately after primary surgery, supraclavicular lymph node metastases were identified as the responsible lesions. None of these seven patients had prior external beam radiation therapy. In two cases, histological confirmation was obtained. In one patient, disease progression could be shown during follow-up. These data suggest that bilateral mediastinal lymph node involvement is a typical site of disease in slowly progressing occult metastatic MTC; the "chimney sign" may represent a typical finding with somatostatin analogues in such cases. Therefore, we believe that even in the case of prior external beam irradiation, mediastinal uptake of octreotide might represent metastatic MTC rather than radiation fibrosis.

Aged↗
PubMed1997

Radiosynoviorthesis with rhenium-186 in rheumatoid arthritis: a prospective study of three treatment regimens.

The aim of this study was to evaluate the efficiency of radiation synovectomy with rhenium-186 in rheumatoid arthritis. In this prospective, randomized trial we compared three different treatment regimens for shoulder, elbow, wrist, hip and ankle joints: group 1, injection of rhenium-186; group 2, injection of rhenium-186 in combination with triamcinolone hexacetonide; group 3, injection of triamcinolone hexacetonide alone. Each treatment group included 50 joints. Patients included in the study had to fulfil the following criteria: (1) they had to have a diagnosis of rheumatoid arthritis (ARA criteria 1988), (2) their disease-modifying drug had to be methotrexate, started at least 6 months prior to injection therapy and given for the entire study time, (3) their nonsteroidal anti-inflammatory drug had to be diclofenac given at a dose of 150 mg/day or less and (4) they were also given prednisolone at a dose of 7.5 mg/day or less. After 3 years of follow-up, 79 joints met these criteria, i.e. 71 joints were excluded from the study: 26 joints because the patients changed the disease-modifying drug (12 joints from group 1, 4 joints from group 2 and 10 joints from group 3); 45 joints because of recurrent synovitis and second-stage treatment (21 joints from group 1, 5 joints from group 2 and 19 joints from group 3). During the follow-up period, joints were assessed for pain, synovitis, joint motion and stage of radiological destruction. Best clinical results and slowest progression in radiological destruction were achieved with the combined injection of rhenium-186 and triamcinolone hexacetonide. Therefore, we recommend this treatment for articulosynovitis with the exception of severe forms, the latter because of the effective penetration range of rhenium-186.

Adolescent↗
PubMed1997

Gaze stabilization by optokinetic reflex (OKR) and vestibulo-ocular reflex (VOR) during active head rotation in man.

Vestibulo-ocular reflex (VOR)-optokinetic reflex (OKR) interaction was studied in normal human subjects during active sine-like head movements in the horizontal plane for a variety of vestibular-optokinetic stimulus combinations (frequency range, 0.05-1.6 Hz). At low to mid frequencies (< 0.2 Hz) the eyes tended to be stabilized on the optokinetic pattern, independently of whether the head, the pattern, or both were rotated. At higher frequencies, the OKR gain was attenuated and, in each of the differing stimulus combinations, the eyes became increasingly stabilized in space. Qualitatively similar results were obtained when, for the same visual-vestibular combinations, the head was passively rotated at 0.05 and 0.8 Hz. The data could be simulated by a model which assumes a linear interaction of vestibular and optokinetic signals. It considers the OKR with its negative feedback loop of primordial importance for image stabilization on the retina and the VOR only as a useful addition which compensates for the limited bandwidth of the OKR during high frequency/velocity head rotations in a stationary visual environment.

Adult↗