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Biomedical subjects

T Wagner

Publications and source records attributed to T Wagner.

At least 145 records · Page 8Linked to original sources
PubMed1997

Coaxial technique: approach to breast core biopsies.

PURPOSE: To assess the feasibility of the coaxial core breast biopsy technique performed under stereotactic and ultrasound (US) guidance in vitro and in vivo. MATERIALS AND METHODS: Biopsies were performed in vitro and in vivo with a coaxial technique. In vitro, the true needle-tip deviation was measured with a breast phantom on a stereotactic device with alteration of x and y axes. In vitro US studies were performed to evaluate the optimal technique for harvesting sufficient material for histologic work-up. In 205 patients, coaxial biopsy was performed in 210 suspicious lesions under US (61 lesions) or stereotactic (patient in the sitting position, n = 67; patient in the prone position, n = 82) guidance. In addition, the coaxial system was used for preoperative localization. Surgery and histologic work-up were performed in all cases. RESULTS: In vitro, the true needle-tip deviation was found to be less than indicated on the stereotactic device. A factor was introduced to correct this error. For US guidance, angulation or rotation of the coaxial needle within the lesion proved to be the best technique to increase the size of histologic specimen. Of the 210 lesions, 112 were benign and 98 were malignant. Agreement between biopsy results and final postsurgical histologic analysis was found in 205 cases (98%). CONCLUSION: The coaxial breast biopsy technique is an accurate, simple, and time-saving method performed under stereotactic or US guidance.

Adult↗
PubMed1997

A somatic cell hybrid panel for distal 17q: GDIA1 maps to 17q25.3.

A somatic cell hybrid panel was constructed consisting of seven hybrids with translocation breakpoints spanning the region 17q23-->q25. Hybrid clones carrying the longarm derivative of chromosome 17 in the absence of the normal chromosome 17 and of the derivative 17 were initially identified by PCR typing for a proximal and distal 17q marker. The translocation breakpoints of the hybrids were then mapped in more detail by PCR analysis for a number of microsatellite markers from chromosome 17q as well as for five gene loci (CACNLG, GH1, SOX9, TIMP2, TK1) previously mapped to the region 17q23-->q25. In addition, the locus for GDIA1 was mapped by FISH to 17q25.3 and fine mapped with the help of the hybrid panel. These seven new hybrids complement the existing somatic cell hybrid panel for the long arm of chromosome 17q.

Animals↗
PubMed1997

[Angiosarcoma of the spleen. Case report and review of the literature].

Angiosarcoma of the spleen is a very rare but highly malignant vascular neoplasm. So far only 140 cases have been reported. A 42-year-old patient is presented in which the radiologic imaging misled to the diagnosis of infiltrating echinococcosis. After splenectomy histological and immunohistochemical staining gave proof of metastatic angiosarcoma. The patient died three months later as a consequence of multiple organ dysfunction syndrome. The literature is reviewed in regard to clinical features, diagnosis and therapy.

Adult↗
PubMed1996

The metabolic impact of rapamycin (sirolimus) in chronic canine islet graft recipients.

The objective of this study was to analyze the impact of rapamycin and/or cyclosporine on the metabolic efficiency of intrasplenic islet autografts in dogs. An insulin modified frequently sampled intravenous glucose tolerance test was carried out before, on the last of 30 days treatment with drug and 30 days after cessation of drug therapy in dogs with stable function 1 to 7 years after total pancreatectomy and intrasplenic islet autografting. Analyses were performed for glucose clearance, insulin release, insulin sensitivity, and other variables. Rapamycin treatment was associated with increased glucose clearance, increased total and stimulated insulin release in response to glucose, and increased fasting plasma insulin level, as well as reduced insulin clearance. Cyclosporine at 300 micrograms/L had little impact on the measured variables. Treatment with rapamycin and cyclosporine showed a similar (although less-marked) pattern of changes to rapamycin alone. Rapamycin, with or without concomitant cyclosporine, was not associated with adverse impact on islet function or glucose metabolism in this canine model of pancreatic islet transplantation.

Animals↗
PubMed1996

Efferent neurons of the lateral line system and their innervation of lateral line branches in a euteleost and an osteoglossomorph.

The efferent neurons of the lateral line system of the euteleost Aplocheilus lineatus and the osteoglossomorph Pantodon buchholzi, both surface feeding fish, were examined by neuronal tract tracing. Besides horse-radish peroxidase, fluorescent dextrans were used as tracers to allow simultaneus visualization of projections from different lateral line branches. Labeled efferent neurons were found in nuclei situated in the medulla ventral of ventricle IV. This position resembles the octa-volateralis efferent nucleus of previous studies. The number of labeled cells in the efferent nucleus is low in both species. Most neurons were found ipsilaterally to the application site, some along the midline and only very few contralaterally. The size of efferent cells differs distinctly between Aplocheilus, possessing small cell-bodies (length 16.5 microm), and Pantodon, which has very large efferent cells (length 47.0 micron). Efferent axon bundles course rostrally in both species, leaving the brain at the level of the anterior lateral line nerve. Only Aplocheilus has in addition lateral axon bundles leaving the brain at the level of the posterior lateral line nerve. After application of one fluorescent tracer to the lateral ramus and a different fluorescent tracer to the superficial ophtalmic ramus in a given animal, double-labeling of efferent cells hardly ever occurs. If the neuromasts I and IV of the dorsal skull of Pantodon are applied with one fluorescent tracer each, approximately 10% of centrally labeled cells are double-labeled. Considering the results of double-labeling, the concept of a differential innervation of lateral line branches is supported and discussed.

Animals↗
PubMed1996

Translocation breakpoints in three patients with campomelic dysplasia and autosomal sex reversal map more than 130 kb from SOX9.

Campomelic dysplasia (CMPD1) and autosomal XY sex reversal (SRA1) are caused by mutations in the SRY-related gene SOX9 on 17q. Unexpectedly, the 17q breakpoints in four CMPD1 translocation cases previously analyzed by us and others map 50 kb or more from SOX9. Here, we present clinical, cytogenetic, and molecular data from a new CMPD1/SRA1 patient with t(6;17)(q14;q24). Fluorescence in situ hybridization has shown that the 17q breakpoint in this case maps to the same region as the breakpoints in the other translocation cases, at least 130 kb from SOX9. Likewise, the breakpoints in two of the previously described cases also map more than 130 kb and, as shown by pulsed field gel electrophoresis analysis, at most 400 kb or 690 kb from SOX9. By using a SOX9 coding sequence polymorphism, expression of both SOX9 alleles has been demonstrated by the reverse transcriptase polymerase chain reaction in lymphoblastoid cells from one of the translocation cases.

Alleles↗
PubMed1996

In-vivo evaluation of random donor platelet concentrates from pooled buffy coats.

Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis. PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus. PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2-3) and long-stored PC (day 4-5). For analysis, platelet increment in the recipient was determined immediately and 16-22 h (mean 20 h) after transfusion, corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly were excluded from the study. Mean platelet content of the PC was 262 x 10(9) for BC-PC and 251 x 10(9) for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9; p = 0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased with further storage by 30% (10.2; p = 0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient platelet increment even when stored for up to 5 days.

Adult↗
PubMed1996

Ifosfamide, carboplatin and etoposide (ICE) combined with 41.8 degrees C whole body hyperthermia in patients with refractory sarcoma.

Two earlier studies resulted in the design of a phase II trial of 41.8 degrees C (x 60 min) extracorporeal whole body hyperthermia (WBH) with ICE, i.e. ifosfamide (5 g/m2), carboplatin (300 mg/m2), and etoposide given with WBH, as well as, day 2 and 3 post-WBH (100 mg/m2) for adult patients with refractory sarcoma. 12 patients entered this trial; all were evaluable. 8 patients had a history of prior chemotherapy associated with disease progression. Following WBH/ICE, 7 partial remissions were observed (58%); 3 patients experienced disease stabilisation; the aforementioned 10 patients each received four cycles of therapy. 2 patients exhibited progressive disease. Episodes of WHO graded (grade 3; grade 4) toxicity observed included: anaemia (2;2); leucopenia (5;7); thrombocytopenia (1;6); renal (0;1). Other toxicities (grade 1 and 2) included: anasarca, diarrhoea, ventricular arrhythmias, pressure sores, and perioral herpes simplex.

Adolescent↗
PubMed1996

Hemostaseologic and hematologic parameters with aspirin and ticlopidine treatment in patients with cerebrovascular disease: a cross-over study.

No direct comparisons of the effects of ticlopidine and aspirin on platelet aggregability, clotting parameters, and blood count are available in a cross-over study design in humans. We investigated 45 patients with cerebrovascular disease. Twenty-one patients received 300 mg aspirin once daily for 2 weeks and then for 2 more weeks received 250 mg ticlopidine twice daily. In 24 other patients, the scheme was reversed. ADP-induced aggregability was lower during ticlopidine treatment; epinephrine- and collagen-induced aggregabilities were lower with aspirin treatment. Platelet counts were higher during ticlopidine than during aspirin treatment (199.6/ nl with aspirin, 213.0/nl with ticlop dine, p = 0.008), probably reflecting less platelet activation and degradation and a longer platelet survival time induced by ticlopidine treatment.

Adenosine Diphosphate↗
PubMed1996

Lemniscal input to identified neurons of the central nucleus of mouse inferior colliculus: an intracellular brain slice study.

Intracellular recordings were performed in 34 neurons in the central nucleus of the inferior colliculus in brain slice preparations of the mouse. Sixteen neurons recorded were stained intracellularly by injection of biocytin and identified as multipolar. After electrical stimulation of the lateral lemniscus, 32 of 34 neurons exhibited postsynaptic potentials (PSPs). Onset latencies of the PSPs were 5.0 +/- 2.8 ms (range 2-12 ms), presumably reflecting the lack of a significant monosynaptic input to most of the neurons recorded. An excitatory PSP (EPSP), often followed by a late inhibitory PSP (IPSP), was present in all neurons which received synaptic input. The IPSPs usually had a reversal potential positive to the cell's resting membrane potential, thus working as shunting inhibitors. Superfusion of the slice with the GABAA antagonist bicuculline resulted in blockade of the IPSP and pronounced prolongation of the EPSP. In 50% of these cases, paroxysmal depolarizing shifts were observed in the presence of bicuculline. Blocking the non-NMDA glutamate receptors with 6,7-dinitroquinoxaline-2,3-dione resulted not only in the total disappearance of EPSPs but also of late IPSPs, indicating that the latter depend on the glutamatergic EPSPs. Furthermore, all neurons recorded must receive substantial innervation from sources within the inferior colliculus, together constituting a complex neuronal network in the inferior colliculus with an important role of the inhibitory neurotransmitter GABA in controlling network properties.

Animals↗
PubMed1996

Influence of cataract surgery on the diabetic eye: a prospective study.

The course of diabetic retinopathy following phacoemulsification and in-the-bag implantation of an intraocular lens (IOL) was studied prospectively in 223 patients (223 eyes). A total of 205 eyes were followed for 6 months. The nonoperated fellow eyes served as a control group. At the time of surgery, 158 patients had no diabetic retinopathy, 45 showed untreated background retinopathy, and 20 had more serious retinopathy with previous coagulation therapy. At 6 months of follow-up, 18.4% of the operated eyes without preoperative retinopathy developed background retinopathy, as did 14.3% of the untreated fellow eyes. Worsening of preexisting diabetic retinopathy during the observation period occurred in 27.6% of the operated eyes and in 29.3% of the non-operated eyes. Although the final visual acuity achieved in our patients was poorer than that reported for nondiabetics, our functional results were satisfying: 94.1% of the operated eyes showed improved visual acuity 6 months postoperatively, 2.4% deteriorated, and 3.4% were unchanged. We therefore conclude that cataract surgery in diabetic patients can be performed with an acceptable risk of complications. Furthermore, worsening of diabetic retinopathy seems to be correlated not with the cataract surgery but with the natural course of diabetic vascular disease.

Cataract↗
PubMed1996

Detection of a hypercoagulable state in nonvalvular atrial fibrillation and the effect of anticoagulant therapy.

The purpose of the study was to evaluate alterations of the hemostatic system and the effect of anticoagulant therapy in nonvalvular atrial fibrillation. A set of molecular hematologic markers was measured prospectively in 69 patients with atrial fibrillation and 28 age-matched patients in sinus rhythm. Significantly elevated levels of thrombin-antithrombin III complex (8.5 +/- 1.6 vs. 2.5 +/- 0.3 micrograms/l; p < 0.001), fibrin monomers (27.1 +/- 3.2 vs. 13.4 +/- 3.7 nM; p < 0.001), D-dimers (788 +/- 76 vs. 405 +/- 46 micrograms/l; p < 0.005), and tissue-type plasminogen activator (9.6 +/- 0.5 vs. 7.2 +/- 0.5 micrograms/l; p < 0.05) were observed in patients with atrial fibrillation compared to those in sinus rhythm. In a subgroup of patients in whom anticoagulant therapy with oral coumadin or standard intravenous heparin was established after the initial study, hemostatic activation decreased significantly. In conclusion, molecular hematologic markers indicate a hypercoagulable state in atrial fibrillation which may characterized a group of patients at elevated risk of thromboembolic disease.

Aged↗
PubMed1995

Open field behaviour in rats: role of metabotropic glutamate receptors.

Previous studies have shown that spatial memory retention is affected by the metabotropic glutamate receptor (mGluR) influencing agents (R,S)-alpha-methyl-4-carboxyphenylglycine (MCPG) and trans-azetidine-2,4-dicarboxylic acid (tADA). In the present investigation we examined whether the mGluR antagonist MCPG (20 mM and 200 mM/5 microliters, respectively) and the agonist tADA (20 mM/5 microliters) have other behavioural effects using the open field test on two successive days. Only minor effects of MCPG (decrease of crossings during the 1st min on day 1) and tADA (increase of rearings on both days) were found. These results suggest that memory influencing doses of MCPG and tADA have no or only little behavioural effects in the open field situation.

Animals↗
PubMed1995

Cytokine production and lymphocyte subpopulations in aged humans. An assessment during nocturnal sleep.

The view of a general impairment of immune functions associated with aging has been challenged by recent studies including a more detailed evaluation of various cytokines and lymphocyte subsets. In the present human study, effects of age on the production of cytokines by T cells and monocytes were assessed, together with age-dependent changes in subset populations of mononuclear cells (MNC). Blood was collected every 30 min during nocturnal sleep in 16 aged (mean: 79.6 +/- 7.5 years) and in 16 young controls (mean: 24.6 +/- 3.1 years). Nocturnal sleep was chosen as a well-defined period within the 24-h cycle with minimal exogenous influences. The in vitro production of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) was measured after mitogen stimulation with lipopolisaccharide from E. coli (LPS). Production of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) was measured after stimulation with phytohemagglutinin (PHA). Regarding MNC subsets, monocytes, lymphocytes, CD3+, CD4+, CD8+, HLA-DR, CD16+, CD25+, and CD19+ were determined. Advanced age was associated with a decreased number of T cells (CD3+) and decreases in the major T cell subsets (CD4+, CD8+, P < 0.001). Production of IL-2 was not affected. However, production of IFN-gamma tended to be enhanced, and numbers of activated T cells (HLA-DR/CD3+), natural killer cells (CD16+), and T cells expressing IL-2 receptors (CD25+/CD3+) were markedly increased in the aged. While monocyte counts were unchanged in the elderly production of IL-1 beta and TNF-alpha mainly derived from these cells, was enhanced (p < 0.05). Results indicate a state of enhanced responsiveness of the T cell compartment and of monocytes in aged which may compensate for the substantial decrease in T cells.

Adult↗