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Biomedical subjects

G W Sybrecht

Publications and source records attributed to G W Sybrecht.

At least 37 records · Page 2Linked to original sources

[Brain metastases of lung cancer: diagnostic accuracy of positron emission tomography with fluorodeoxyglucose (FDG-PET)].

The value of FDG-PET in oncology is currently investigated in clinical studies. There is only limited information on the usefulness of FDG-PET in the evaluation of distant metastases of lung cancer. The purpose of the present prospective investigation was to determine the diagnostic accuracy of FDG-PET in the detection of brain metastases of lung cancer. After intravenous injection of 220 +/- 50 MBq F-18-deoxyglucose PET acquisition was carried out using an ECAT ART scanner (CTI Siemens). Images were reconstructed using a filtered backprojection with a Hanning filter. PET data were analyzed by visual interpretation of coronal, sagittal and transversal slices. PET scans were interpreted by two experienced nuclear medicine physicians without prior knowledge of the results of other imaging studies or clinical data. Between March 1997 and July 1998 whole-body PET was performed in 417 patients with suspected lung cancer. 402 patients were used for statistical analysis. Based on conventional brain imaging with CT (occasionally MRI), brain metastases were suspected in 17 patients (prevalence 4.2%). For FDG-PET alone, sensitivity was 82% (14/17) and specificity 38% (14/37). Therefore, diagnostic accuracy of FDG-PET in detection of brain metastases was 93.5%. The low specificity of FDG-PET can be explained by reduced tracer uptake mainly due to brain infarction or vascular encephalopathy in this group of elderly patients. Our results indicate that due to its low specificity FDG-PET is not useful for the evaluation of brain metastases in the primary staging of patients with lung cancer.

Adult↗

[Abscessed pneumonia caused by Pseudomonas aeruginosa as an occupational disease in a metal driller].

We report the case of a 29-year-old man without immunodeficiency who acquired Pseudomonas aeruginosa pneumonia complicated by pulmonary abscess. The source of infection could be identified as aerosolized metalworking fluid at his workplace contaminated with Pseudomonas aeruginosa. A high titer of specific IgG antibodies (type-III-sensitization, Gell & Coombs) against Pseudomonas aeruginosa has been identified in the patients serum as an indicator for longstanding occupational airborne exposure to contaminated metalworking fluid. This community-acquired pneumonia has been reported to the industrial injuries insurance as an occupational disease for discussion of legal consequences and development of effective measures of prevention.

Adult↗

Clinical significance of sleep-related breathing disorders in patients with implantable cardioverter defibrillators.

The prevalence and clinical significance of sleep-related breathing disorders (SRBDs) in patients with cardiac disease and a history of life-threatening ventricular tachyarrhythmias is unclear. Forty consecutive recipients of implantable cardioverter defibrillators (ICDs) with cardiac disease and a documented history of spontaneous, life-threatening, ventricular tachyarrhythmias underwent full night polysomnography. SRBDs were diagnosed if the apnea/hypopnea index was > 10. SRBD were diagnosed in 16 of 40 patients (40%): central sleep apnea (CSA) was present in 9 of these 16 patients (56%), 8 of whom had associated Cheyne-Stoke respiration. Seven of the 16 patients with SRBD (44%) had obstructive sleep apnea (OSA). Patients with and without SRBDs were comparable with respect to left ventricular ejection fraction, NYHA classification, underlying heart disease, ICD indications, and concomitant antiarrhythmic drug and beta-blocker therapy. Patients were followed prospectively for 2 years. ICD-treated ventricular tachyarrhythmias occurred in 10 of 24 patients (42%) without SRBD, in 4 of 9 patients (44%) with CSA, and in 3 of 7 patients (44%) with OSA (NS). The numbers and circadian distributions of episodes recorded during follow-up in patients without SRBD versus with CSA or OSA were not significantly different (14 +/- 25, median = 4 vs 4 +/- 5, median = 2.5 vs 15 +/- 15, median = 7, respectively). The 2-year mortality, which was entirely attributable to nonsudden cardiac events, was highest in patients with CSA (4/9 [44%], vs 0/7 [0%] with OSA, vs 3/24 patients (12.5%) without SRBD; P < 0.05).

Aged↗

[Effect of oxygen (FI02: 0.35) on the aerobic capacity in patients with COPD].

BACKGROUND: Disability in patients with chronic obstructive pulmonary disease has led to the development of rehabilitation programs to increase exercise tolerance. OBJECTIVE: To determine, if the effect of training can be improved by giving supplemental oxygen during exercise. MEASUREMENTS: Ten male patients with COPD (mean FEV1 = 43.2 +/- 17.1% pred) underwent a five day per week cycle ergometer training program for four weeks at least 45 minutes per day at a constant workload of 80% of their highest achieved workrate--measured in an incremental exercise test before training. At this workrate all patients performed exercise above their anaerobic threshold. Five patients were breathing 35% oxygen during exercise, five were breathing roomair (randomised, single blind). To evaluate and compare the results of training before and after the program all patients performed an incremental exercise test (continuously increasing workrate) with roomair. RESULTS: In the group breathing 35% O2 during training the maximally achieved power in the incremental exercise test after training was 15.9% higher. In the group breathing roomair during training the maximally achieved power after training was 36.3% higher than before (p < 0.05). This group also showed significant reductions in lactate levels (p < 0.05) after training at the maximum workload achieved in the pre-training test. CONCLUSIONS: Training in the roomair-group resulted in a significant increase in the maximum power and total amount of work. In this group training could induce a physiologic response (increase of aerobic capacity), which was shown by significantly lower lactate levels at a comparable workload.

Exercise↗

[Thoracic actinomycosis--a case report].

BACKGROUND: Actinomycosis is caused by a variety of gram-positive anaerobic or microaerophilic rods belonging to the genus Actinomyces or Propionibacterium. The production of suppurative abscesses or granulomas that eventually develop draining sinuses are hallmarks of the disease. We describe the case of a 55 year old smoker who presented himself 4 months ago with right thoracic pain and an unproductive cough. He developed a warm, red mass in the lower part of the right thorax. We performed an ultrasound guided needle aspiration and the pathologic examination revealed typical sulfur granules and masses of neutrophils in the aspirate. After surgical resection of the abscess and under high-dose therapy with penicillin G the further course of disease was uneventful. CONCLUSIONS: Although uncommon, thoracic actinomycosis should always taken into account in the differential diagnosis of chronic inflammatory processes that involve the pulmonary parenchyma or pleural space.

Actinomycosis↗

[Palliative accelerated irradiation for advanced non-small-cell lung bronchial carcinoma: results of a pilot study].

In order to reduce the aggressivity of radiotherapy of very advanced non-small-cell lung cancer (NSCLC), and to shorten treatment time, a palliative accelerated irradiation regimen (PAIR) was developed. Before the onset of a randomised study, we performed a one-year pilot study, of which the paper presented here gives the results after complete follow-up. 34 patients (S) with locally inoperable advanced NSCLC stage III (74%) and IV (26%) were irradiated with accelerated fractionation schedule, focussing on tumour and mediastinum, with a total dose of 32 Gy (PAIR, 2 x 2 Gy/d). Treatment results were compared to those of a group of 178 controls (K) treated conventionally, who were selected from a preexisting database according to study inclusion criteria (tab. 2-5 stage III 65%, IV 35%). 105 of them had been treated with a total dose of 60 Gy (K60). After complete follow-up a final evaluation was made. Local control did not differ significantly between both groups, and not between groups S and K60 (tab. 6, fig. 2). Median survival for all patients (S + K) was 6 months. With 8.7 months, that of the study patients (S) was significantly longer than that of the controls (K, fig. 1). This was also true of stage III. Comparison with the 60-Gy-controls (K60) did not reveal significant survival differences. In Cox regression analysis independent prognostic factors were: Karnofsky index, UICC stage, and N stage. Concerning the palliation of tumour-related symptoms, both therapies were comparable (tab. 7). The side-effects were moderate and also comparable. These results induced us start a randomized study comparing both regimens in respect of prognosis and palliation.

Carcinoma, Non-Small-Cell Lung↗

[Pneumology].

Explore the source record for details and available documents.

Forecasting↗

[Clinical significance of sleep apnea disorders after implantation of a cardioverter-defibrillator in patients with cardiac disease and sustained ventricular tachyarrhythmia].

The purpose of our study was to determine the prevalence of sleep related breathing disorders (SRBD) in patients with an implantable cardioverter-defibrillator (ICD) and to evaluate prospectively the possible influence of SRBD on arrhythmia recurrence and circadian arrhythmia variation as well as on cardiac mortality during long-term follow-up. Forty consecutive ICD recipients with cardiac disease and a documented history of spontaneous, life-threatening, ventricular tachyarrhythmias underwent full-night polysomnography and were followed for 2 years. In 16 of 40 patients (40%), SRBD were diagnosed (Apnea/Hypopnea Index (AHI) > 10); in 9 of these 16 patients (56%) central sleep apneas (CSA) occurred (in 8 of these 9 patients in combination with Cheyne-Stokes respiration). Seven of the 16 patients with SRBD (44%) revealed obstructive sleep apneas (OSA). AHI was 32 +/- 15 (12-60) in patients with CSA and 32 +/- 27 (11-86) in patients with OSA. Patients with and without SRBD were comparable concerning left ventricular ejection fraction, NYHA classification, cardiac disease, ICD indication, and concomitant medication. ICD registered ventricular tachyarrhythmias occurred in 10 of 24 patients (42%) without SRBD, in 4 of 9 patients (44%) with CSA, and in 3 of 7 patients (44%) with OSA. The numbers and circadian variation of episodes registered during follow-up in patients without SRBD, with OSA or CSA were comparable (14 +/- 25, median 4 vs 15 +/- 15, median 7 vs 4 +/- 5, median 2.5). The 2-year cardiac mortality was highest in patients with CSA (4/9 (44%) vs. 0/7 patients (0%) with OSA vs 3/24 patients (12.5%) without SRBD. Thus, the prevalence of SRBD in patients with chronic heart failure and a history of malignant ventricular tachyarrhythmias is high (40%) and the occurrence of CSA seems to be predictive for cardiac mortality in these patients. An influence of moderate SRBD on arrhythmia recurrence and circadian variation of spontaneous sustained tachyarrhythmic events could not be demonstrated.

Aged↗

A phase I study of paclitaxel in combination with etoposide in patients with stage IIIB/IV non-small cell lung cancer (NSCLC).

Paclitaxel is a new antineoplastic agent with activity in lung cancer. This phase I clinical trial was designed to determine the maximum tolerated dose (MTD) of paclitaxel in combination with etoposide in previously untreated patients with non-small cell lung cancer (NSCLC). Doses of paclitaxel were in the range of 150-225 mg/m2 (d1) and of etoposide in the range of 100-120 mg/m2 (d2-4). The drugs were administered by i.v. infusion over 3 h (paclitaxel) and 2 h (etoposide). The patients received four courses at 21-day intervals. Twenty-four patients (six female, 18 male) entered the trial. The characteristics of the patients were as follows: median age 64 (55-73) years; Karnofsky index 80% (70-90%); stage IIIB n = 7, IV n = 17; histology, 14 adenocarcinoma, 10 squamous carcinoma. Hypersensitivity reactions after paclitaxel were not observed. The most relevant toxic effect observed was neutropenia (WHO grade 3-4). Three episodes of febrile neutropenia, two episodes of absolute neutropenia (< 100/microliter for > 3 days), and one case of mucositis (WHO grade > or = 3 for > 7 days) occurred. It can be concluded that the MTD of paclitaxel in combination with etoposide was reached at doses of 200 mg/m2 paclitaxel (d1) and 100 mg/m2 etoposide (d2-4).

Aged↗

[Diagnostic value of somatostatin receptor scintigraphy with indium-111 pentetreotide in small-cell bronchial carcinoma].

Small-cell lung cancer (SCLC) cells may express somatostatin receptors [14]. Receptor-positive tissue can be visualised in vivo by scintigraphy with radiolabelled somatostatin analogues. In a prospective study we examined 18 patients with histologically proven SCLC for the diagnostic value of somatostatin receptor scintigraphy using indium-111 pentetreotide. Planar whole body scanning was performed 4 and 24 hours after administration. Additional SPECT imaging of the thorax and the abdomen was done at 24 hours. The results were compared with conventional staging procedures: ultrasound, x-ray, computed tomography and bone scintigraphy. In all 18 patients the primary tumour was correctly identified. Out of 13 patients with mediastinal lymphoma formation 10 patients showed positive SRS. In 2 more patients SRS showed mediastinal uptake while CT scanning was negative. The detection of distant metastases in patients with extensive disease was true positive in 8 cases (OSS, HEP, BRA), false negative in 4 cases (PLE, ADR, HEP), corresponding to a sensitivity of 67%. In 2 patients cerebral metastases were no longer detectable by SRS after previous local irradiation. Even though the method is limited in respect of revealing distant metastases in the upper abdominal area due to physiological uptake in liver, spleen and kidneys, differentiation between limited disease (LD) and extensive disease (ED) was possible in all cases. We conclude that [111In]pentetreotide scintigraphy is a suitable method for the detection of SCLC primary tumours and a substantial tool for differentiation between LD and ED if combined with ultrasonography of the upper abdomen.

Adult↗

[Unusual metastasis of a malignant pleural mesothelioma].

Usually malignant pleural mesothelioma causes pain and dyspnoea due to local invasion of the chest wall and compression of the lung. Distant metastases rarely cause symptoms. We report on a patient with an epithelial subtype of malignant pleural mesothelioma who presented himself after chemo- and immunotherapy with shortness of breath and loss of weight due to a temporo-mandibular joint and a new nodular shadow in the contralateral lung. The prior diagnosis of an epithelial subtype of pleural mesothelioma was confirmed histologically in a pleural biopsy as well as in the resected orofacial metastases.

Aged↗

Amplification of the genes BCHE and SLC2A2 in 40% of squamous cell carcinoma of the lung.

Gene amplification is a common genetic change in human cancer cells. Previously, we provided the first evidence for gene amplification at chromosome band 3q26 in squamous cell lung carcinoma. In this study, the following analyses were performed: (a) we evaluated biopsies and paraffin-embedded tissues of 16 additional squamous cell lung carcinomas for gene amplification using reverse chromosome painting. Of the 16 tumors, 3 tumors showed an amplification of the entire long arm of chromosome 3, and 3 tumors showed various amplifications on 3q, all of which involved chromosome band 3q26; (b) we tested eight genes encompassing region 3q25-qter in two different tumors to identify amplified genes on chromosome 3q. The genes SI, BCHE, and SLC2A2 were amplified in both tumors; and (c) we analyzed 15 additional paraffin-embedded tissues to determine the amplification frequency of these genes. Of the 15 squamous cell lung carcinomas, 6 showed amplification for at least 1 of the genes, with BCHE and SLC2A2 as the genes most frequently amplified. Together, our reverse chromosome painting data and our PCR analysis indicate gene amplification at 3q26 in 40% of all squamous cell lung carcinomas with BCHE and SLC2A2 as possible target genes of the amplification unit in squamous cell lung carcinoma.

Blotting, Southern↗

A new method for data presentation in incremental cardiorespiratory exercise testing.

In incremental cardiopulmonary exercise testing, the averaging of data is usually performed to provide group mean data for statistical purposes. They are usually presented as averaged maximum values, or as averaged data at different exercise levels. However, during incremental exercise testing the change in metabolic status may vary between subjects, thus averaging data may not classify the metabolic status accurately. We present an averaging method using a segmented ordinal scale based on individual maximal work performance and the anaerobic threshold (AT). Individual exercise data are grouped into ten classes ranging from unloaded exercise to maximal exercise. The classes are defined in relation to the AT, resulting in an ordinal scale of four classes for exercise data below the AT, one class at the AT and five classes beyond the AT. Resting and unloaded pedalling are treated as separate classes. For evaluation, this method of classification is compared to one based on an absolute scale of oxygen uptake (Cabs) and to another based on a relative scale in 10% steps of maximal oxygen uptake (Crel). Ten healthy male subjects (mean age 23.3 years) performed a ramp cycle ergometer test. When using the Cabs classification method for mean data averaging, mean values for performance at high-intensity exercise were calculated using data from only two of the ten subjects because of variations in individual work capacity. In addition, the AT data were distributed across four classes, thus anaerobic and aerobic exercise data were mixed. Using the Crel classification method enabled data for all ten subjects to be included in the calculation of every data point, but the AT values were still distributed across three classes, resulting in the mixing of anaerobic and aerobic exercise data. However, using the segmented ordinal scale method of classification enabled data from all ten subjects to be included in the calculation of all data points, and it permitted the grouping of the AT values into one class. Thus, this latter method more accurately represents the data of the whole group under study and it allows the metabolic status of the subjects to be taken into consideration.

Adult↗

Translation initiation factor eIF-4gamma is encoded by an amplified gene and induces an immune response in squamous cell lung carcinoma.

Amplification of cellular oncogenes is an important mechanism of altered gene expression in human cancers. Using comparative genomic hybridization we recently identified an amplification at 3q26.1-q26.3 in 30% of squamous cell carcinomas of the lung. A variety of methods including microdissection-mediated procedures permit cloning of genes encoded within amplified domains but do not directly lead to the identification of biologically relevant genes. In this study, we have circumvented this problem by combining an immunological and molecular genetic approach to analyze squamous cell lung carcinoma. To identify both amplified and tumor relevant genes, we generated a cDNA expression library from a tumor with the 3q amplification and hybridized the expressed recombinant polypeptides with the autologous serum. Of 400000 cDNA clones we identified 17 antigens which induce an immune response in a patient with squamous cell lung carcinoma. While most clones represent individual genes sequence analysis revealed that four of the 17 cDNAs are nearly identical with the eukaryotic translation initiation factor (eIF)-4gamma recently assigned on 3q. We demonstrated that the gene for eIF-4gamma was amplified within 3q26-q27 in independent squamous cell lung carcinomas. In this study, we report the identification of several antigens which elicit an immune response in a squamous cell lung carcinoma patient including eIF-4gamma. eIF-4gamma is encoded by an amplified gene and possibly plays a crucial part in the development of squamous cell lung carcinoma.

Base Sequence↗