Search PubMed⌕ Search

Biomedical subjects

T Wagner

Publications and source records attributed to T Wagner.

At least 343 records · Page 19Linked to original sources

Non-invasive determination of effective pulmonary blood flow: evaluation of a simplified rebreathing method.

PRIMARY OBJECTIVE: To evaluate a new technical approach to measuring effective pulmonary blood flow (PBF) in mechanically ventilated patients. RESEARCH DESIGN: Prospective clinical study; evaluation of accuracy and reproducibility. METHODS: Effective pulmonary blood flow was determined non-invasively in 32 mechanically ventilated patients by using a new rebreathing system (PBF(rb)). Cardiac output corrected for intrapulmonary shunt was taken as reference value (PBF(thd)). Bias, precision and reproducibility of the rebreathing method were calculated from duplicate measurements in each patient. MAIN RESULTS: The mean difference between PBF(rb) and PBF(thd) was - 0.67 +/- 0.83 l min(-1). The mean difference between duplicate measurements with the rebreathing system was 0.16 +/- 0.36 l min(-1). However, the accuracy of the rebreathing system tended to decrease in patients with PBF levels greater than 6 l min(-1). CONCLUSIONS: The new device appears to be reliable for determination of PBF values below 6 l min(-1). With this limitation, the present method may be used as a trend-indicator of PBF in mechanically ventilated patients.

Adult↗

Comorbid anxiety and affective disorder in alcohol-dependent patients seeking treatment: the first Multicentre Study in Germany.

The goals of this study were to describe demographic variables, drinking history, and the 6-month prevalence of Axis I comorbidity among alcohol-dependent subjects in GERMANY: The variables: amount of alcohol consumption, age at onset of the first alcohol consumed, age at onset of daily alcohol consumption, age at onset of withdrawal symptoms and number of detoxifications were related to the different comorbid disorders and gender. In this study, 556 patients from 25 alcohol treatment centres were enrolled between 1 January 1999 and 30 April 1999. After a minimum of 10 days of sobriety patients who fulfilled ICD-10 and DSM-IV criteria of alcohol dependence were interviewed for data collection using the Mini-DIPS (German version of the Anxiety Disorders Interview Schedule) and a standardized psychosocial interview. The 6-month prevalence of comorbid Axis I disorders was 53.1%. Among the patients with comorbidity, affective and anxiety disorders were most frequent. Comorbid stress disorder was associated with an early start of drinking, an early beginning of withdrawal symptoms, highest number of detoxifications, and the highest amount of alcohol consumed. Female patients with anxiety disorder consumed more alcohol and started earlier than females without this comorbid disorder. The data do not answer the question of the pathogenesis of comorbid disorders and alcoholism, but indicate that stress disorders in alcoholic patients and anxiety disorders in female alcoholics influence the course and severity of alcoholism.

Adult↗

Fluorescence assay for the detection of adherent Candida yeasts to target cells in microtest plates.

We describe an assay based on photometric analysis for the measurement of adherence of Candida species to epithelial target cells (Vero cell line). Adherent Candida cells were detected by staining the cells with the fluorescent dye Calcofluor white (CFW), which binds to chitin and glucan in the yeasts. The tests were performed on microtest plates, which were analysed automatically by fluorescence plate readers. The assay is based on the following steps: (i) coating of the microtest plates with target cells (e.g. Vero cells); (ii) infection with Candida: (iii) staining of Candida with CFW; (iv) rinsing to remove non-adherent Candida cells and unbound dye; (v) detection of adherent fluorescent Candida cells. The test was able to detect 4 x 10(4) cells ml-1. The standard deviation was +/- 8%. Day-to-day variation was +/- 10% at most. The adherence of strains of different Candida species was assayed by a standard procedure. The results confirmed the order of adherence, with C. albicans ranking first, followed by C. tropicalis, C. parapsilosis and C. glabrata.

Animals↗

Local hyperthermia, radiation, and chemotherapy in locally advanced malignancies.

Tumor size is a significant prognostic variable for attaining complete regression (CR) with local hyperthermia (HT) and radiation therapy (RT). The addition of weekly chemotherapy was evaluated to improve the efficacy of thermoradiotherapy in poor-prognosis lesions (i.e. > or = 7 cm2 or > or = 14 cm3) which have an expected CR rate of approximately 30 +/- 8%. Patients were entered into a two-arm phase-II study: arm 1 = breast cancer (10 patients), ifosfamide (1.5 g/m2) + epirubicin (20 mg/m2) + HT + RT; arm 2 = sarcoma (7 patients) and head and neck cancer (9 patients), cisplatin (40 mg/m2) + HT + RT. Therapy encompassing 106 triple-modality sessions was generally well tolerated for both arms; 2 instances of grade-3 and 1 of grade-4 (arm 2) local toxicity (WHO criteria) were observed. There were 4 instances of grade-3 myelosuppression (arm 1). The CR rates for arms 1 and 2 were 70 and 19%, respectively, suggesting that the combination of ifosfamide/epirubicin/HT/RT deserves further investigation in the context of localized breast cancer.

Adult↗

Portal vein thrombosis in a 17-year-old female adolescent with essential thrombocytosis.

A 17-year-old girl known to suffer from essential thrombocytosis (ET) was admitted with severe abdominal pain that was due to sonographically verified portal and hepatic vein thrombosis. ET is a well-documented disease and portal vein thrombosis has often been reported in adults but not in children and adolescents suffering from ET. Coincidence of ET, urinary tract infection, oral contraception, and cessation of acetylsalicylic acid therapy might be responsible for the early manifestation of portal and hepatic vein thrombosis in our patient.

Adolescent↗

A specific role for group I mGluRs in hippocampal LTP and hippocampus-dependent spatial learning.

Metabotropic glutamate receptors (mGluRs) have been implicated in long-term potentiation and in learning and memory formation. In this study, we tested the effects of group I mGluR inhibition on synaptic plasticity and learning of rats at different levels of organization (1) in the hippocampal slice preparation; (2) in freely moving animals implanted with chronic hippocampal electrodes; and (3) in different spatial learning paradigms. To allow a direct comparison of the effects obtained the same doses were used in all paradigms. Bath-application of the selective group I mGluR antagonist (S)4-carboxyphenylglycine (4-CPG) impaired a decremental long-term potentiation (LTP) induced by a weak tetanization paradigm, but failed to affect a robust LTP generated by strong tetanization. In contrast, 4-CPG impaired a robust LTP in freely moving animals if applied 30 min before tetanization. The same dose of 4-CPG only impeded spatial learning mildly in the eight-arm radial maze and had no effect on a simple configuration of the Y-maze spatial alternation task. In the more difficult configuration of this task, however, 4-CPG caused complete amnesia. The lack of state-dependent 4-CPG actions and the absence of any 4-CPG effects in the open-field test classify the obtained retention deficit as a selective impairment of memory storage. Our results indicate a specific role of group I mGluRs in certain types of synaptic plasticity and of spatial learning.

Animals↗

Trofosfamide in patients with pancreatic cancer.

BACKGROUND: In a previous phase II trial of ifosfamide (IFO) several patients with pancreatic cancer responded to therapy (1). Trofosfamide (TROFO) is an orally taken oxazaphosphorine prodrug. Metabolic products of TROFO include ifosfamide (IFO) and cyclophosphamide (CYCLO). In clinical pilot studies with TROFO against refractory malignancies mild toxicity was reported. PATIENTS AND METHODS: Since virtually all patients with advanced pancreatic cancer are symtomatic, we designed and conducted a prospective phase II trial to evaluate the activity of single agent therapy with TROFO given orally continuously (three times 50 mg daily), and to assess the toxicity, duration of remission, and overall survival of the treated patients. RESULTS: 16 patients were enrolled onto the study. In one patient a PR has been observed; the mayor response rate was 6%. The mayor toxicity was bone marrow toxicity with granulocytopenia (WHO grade II) and anemia (WHO grade II) in virtually all patients. CONCLUSION: Single agent therapy with TROFO in patients with pancreatic cancer is safe and well tolerated; however, it shows low clinical activity.

Adenocarcinoma↗

Bilateral ablation of auditory cortex in Mongolian gerbil affects discrimination of frequency modulated tones but not of pure tones.

This study examines the role of auditory cortex in the Mongolian gerbil in differential conditioning to pure tones and to linearly frequency-modulated (FM) tones by analyzing the effects of bilateral auditory cortex ablation. Learning behavior and performance were studied in a GO/NO-GO task aiming at avoidance of a mild foot shock by crossing a hurdle in a two-way shuttle box. Hurdle crossing as the conditioned response to the reinforced stimulus (CR+), as false alarm in response to the unreinforced stimulus (CR-), intertrial activity, and reaction times were monitored. The analysis revealed no effects of lesion on pure tone discrimination but impairment of FM tone discrimination. In the latter case lesion effects were dependent on timing of lesion relative to FM tone discrimination training. Lesions before training in naive animals led to a reduced CR+ rate and had no effect on CR- rate. Lesions in pretrained animals led to an increased CR- rate without effects on the CR+ rate. The results suggest that auditory cortex plays a more critical role in discrimination of FM tones than in discrimination of pure tones. The different lesion effects on FM tone discrimination before and after training are compatible with both the hypothesis of a purely sensory deficit in FM tone processing and the hypothesis of a differential involvement of auditory cortex in acquisition and retention, respectively.

Animals↗

Extrapulmonary location of sarcoidosis.

Two cases of sarcoidosis located outside the lungs are reported. In both cases the symptoms of the sicca syndrome were in the foreground. In the first case other clinical manifestations included mediastinal and retroperitoneal lymphadenopathy, and lacrimal gland impairment. In the other case the symptoms of the sicca syndrome were associated with polyneuropathy and maculopapular skin rash. The diagnosis of sarcoidosis was confirmed by histological examination of a biopsy specimen of lower lip mucosa in the first case, and biopsy of skin lesion in the second case. Abnormal results of laboratory tests included only raised erythrocyte sedimentation rate, in both cases and presence of circulating immune complexes in one case. Serological tests failed to demonstrate the presence of rheumatoid factor, antinuclear and anti-ds DNA antibodies. No decrease was observed also in the haemolytic activity of the complement, and cryoglobulins were absent. Regression of clinical signs was obtained in both cases after treatment with glucocorticosteroids.

Adult↗

[Value of thrombolytic therapy in deep venous thrombosis].

Thrombolytic therapy in a large number of patients may prevent post-thrombotic symptoms occurring as late consequences of deep vein thrombosis. In clinical studies, streptokinase either in conventional low dose, longterm, intravenous or in repeated intravenous short term ultra high dose regimens, urokinase and recombinant tissue-type plasminogen activators: all these plasminogen activators have been confirmed to successfully restore the patency of veins. As deep vein thrombosis generally extends over longer distances and are mostly older before being diagnosed, a lysing period of a couple of days must be taken into account. On the other hand, deep vein thromboses aged more than 2 weeks generally are no longer amenable to thrombolytic treatment. Due to their lack of short-term and long-term hazards, thromboses of the arms and the lower legs are not regarded an ideal indication for thrombolysis. Up to now, none of the currently available plasminogen activators has demonstrated superiority over the others, neither in respect of efficacy nor safety. With streptokinase intermittent intravenous ultra-high doses success rates of up to 80% (complete plus partial recanalization) can be achieved within a three-day treatment period. For its accompanying increased hazard of fatal pulmonary embolism, however, it is considered to be contraindicated in patients with pelvine thrombosis. Furthermore, contraindications to streptokinase such as streptococcal infections and prior lysis with streptokinase should always be kept in mind. In these cases streptokinase may be substituted by rt-PA, which, however, in the indication of deep vein thrombosis, is still not well documented today.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Tests↗