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T Koch

Publications and source records attributed to T Koch.

At least 37 records · Page 2Linked to original sources

The challenge of Terri Schiavo: lessons for bioethics.

This essay reviews a range of issues arising from the complex case of Terri Schiavo and the lessons the case raises for bioethicists. It argues that embedded in the case is a broader controversy than is immediately evident, one involving the definitions by which bioethics judge cases of extreme physical and psychological limits, in its principled form of address. Further, it argues that bioethicists who assume the issues involved in the case are settled miss the point of the emotional responses it has brought forth.

Bioethical Issues↗

Possibilities to control the horse chestnut leaf miner (Cameraria ohridella) in urban environments.

The continuous epidemic infestation of horse chestnuts by C. ohridella is a serious aesthetic and economic problem in urban environments. The aim of the presented studies was therefore to develop control measures which meet the special needs of urban plant protection. Removal of infested leaves in autumn and appropriate disposal of the leaflitter is the only practicable measure to reduce infestation levels so far. Another two methods, which are currently in an experimental stage, had an impact on the leafminer populations. A gelformulated combination of the C. ohridella-pheromone with a contact insecticide as attract-and-kill-system proved to be efficient at low population levels. Easily applicable and safe banks of systemic insecticides turned out to be effective in killing preimaginal stages of the leafminer on young trees. The complex of parasitoids attacking C. ohridella is comparable to that of other leafminers. Nevertheless, parasitism rates are very low at present and far away from having any controlling effect on the pest insect.

Aesculus↗

A fine balance--one-lung ventilation in a patient with Eisenmenger syndrome.

A 38-yr-old woman with an atrial septum defect and Eisenmenger syndrome was scheduled for a lung biopsy via thoracoscopy during one-lung ventilation. Fluids were given to increase central venous pressure to 8 mm Hg, an epidural catheter was inserted at the sixth thoracic intervertebral space and ropivacaine 0.3%, 6 ml were given. Careful balance of systemic and pulmonary vascular resistance is crucial in Eisenmenger syndrome, so norepinephrine (0.14 mg kg(-1) min(-1)) was infused before general anaesthesia was started with fentanyl 4 mg kg(-1), ketamine 2 mg kg(-1), pancuronium 1 mg and succinylcholine 2 mg kg(-1). Anaesthesia was maintained with propofol 4-8 mg kg(-1) h(-1). To control pulmonary artery pressure, ventilation was performed with oxygen 100% and nitric oxide 20 ppm. Surgery and anaesthesia course were uneventful and the patient was extubated. However, pleural haemorrhage required treatment with blood components, re-intubation on the second postoperative day and removal of the haematoma by mini-thoracotomy. A step-by-step approach using a balanced combination of regional and general anaesthesia, controlled fluid administration, norepinephrine and inhaled nitric oxide preserved a stable circulation even during one-lung ventilation. The diagnostic value of lung biopsy must be weighed against the possibility of life-threatening haemorrhage.

Adult↗

[Reduction in the aggressiveness of ventilation by inhalation of perfluorohexane after therapy of oleic acid-induced respiratory failure].

INTRODUCTION: The application of perfluorohexane (PFH) vapor led to an improvement of oxygenation and mechanical lung function in a model of oleic acid-induced ARDS in sheep. The aim of this study was to investigate the effects of PFH on gas exchange over an extended time period and to reduce the invasiveness of ventilation. METHOD: ARDS was induced in sheep ( n=12) by injecting 0.1 ml/kg body weight oleic acid intravenously. Six sheep were treated for 30 min with 18 vol.% PFH (PFH-Tx) and followed up over a time period of 240 min while untreated sheep ( n=6) served as controls. Subsequently the F(I)O(2) was reduced to generate a p(a)O(2) between 100-140 mmHg. Gas exchange, respiratory and hemodynamic data were collected at regular intervals. Data were analysed using covariance analysis. RESULTS: PFH treatment led to an improvement in oxygenation ( p<0.01) and in mechanical lung function ( p<0.01). Furthermore, mean pulmonary artery pressure ( p<0.01) and shunt ( p<0.01) were lower in PFH-Tx. F(I)O(2) could be reduced in all PFH-treated animals ( p<0.01). CONCLUSION: Treatment of oleic acid-induced lung injury with PFH vapor improved oxygenation and mechanical lung function over a extended time period allowing a reduction in the invasiveness of ventilation.

Animals↗

Effect of LNA modifications on small molecule binding to nucleic acids.

Locked nucleic acid (LNA) is a conformationally constrained DNA analogue that exhibits exceptionally high affinity for complementary DNA and RNA strands. The deoxyribose sugar is modified by a 2'-O, 4'-C oxymethylene bridge, which projects into the minor groove. In addition to changing the distribution of functional groups in the groove and the overall helical geometry relative to unmodified DNA, the bridge likely alters the hydration of the groove. Each of these factors will impact the ability of small molecules, proteins and other nucleic acids to recognize LNA-containing hybrids. This report describes the ability of several DNA-intercalating ligands and one minor groove binder to recognize LNA-DNA and LNA-RNA hybrid duplexes. Using UV-vis, fluorescence and circular dichroism spectroscopies, we find that the minor groove binder as well as the intercalators exhibit significantly lower affinity for LNA-containing duplexes. The lone exception is the alkaloid ellipticine, which intercalates into LNA-DNA and LNA-RNA duplexes with affinities comparable to unmodified DNA-DNA and RNA-DNA duplexes.

Bisbenzimidazole↗

Unheard heroes.

Explore the source record for details and available documents.

Academic Medical Centers↗

Spleen involvement in Hodgkin's lymphoma: assessment and risk profile.

Diagnostic laparotomy is no longer routinely performed in Hodgkin's lymphoma and noninvasive diagnosis of spleen involvement remains uncertain. In order to assess the probability of splenic involvement based on clinical parameters, we retrospectively analyzed data on patients of the German Hodgkin's Lymphoma Study Group (GHSG) who underwent staging laparotomy and for whom splenic weight and size were available. Our study included 376 patients with Hodgkin's lymphoma who underwent staging laparotomy and splenectomy according to the treatment policy of the GHSG between February 1981 and January 1993. Univariate and multivariate analyses of pretherapeutic clinical characteristics and splenic weight were performed in order to predict the probability of splenic involvement. Computed tomographic (CT) images of 25 patients were available and used to correlate radiological splenic size and pathological splenic weight. In 171 of 376 patients spleen involvement was found. Average weight of the spleens was 258 g (+/-257) ranging from 55 to 3290 g. All spleens with a weight above 2000 g showed disease involvement, while those under 150 g were never involved. In the multivariate analysis, splenic weight ( p<0.001), erythrocyte sedimentation rate ( p<0.001), and clinical stage ( p<0.01) were found to be independently prognostic for spleen involvement. Splenic weight was highly correlated with a spleen index defined as the product of length, width, and thickness measured by CT (correlation coefficient: 0.93). By applying the identified risk factors in clinically staged patients spleen involvement can be determined. Spleen weight can be estimated with the help of a spleen index. Above an index of 1000 the probability of spleen involvement is higher than 90%. This might be of outstanding importance for patients being scheduled for involved field radiation.

Adolescent↗

14-day variant of the bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone regimen in advanced-stage Hodgkin's lymphoma: results of a pilot study of the German Hodgkin's Lymphoma Study Group.

PURPOSE: This multicenter pilot study assessed the feasibility and efficacy of a time-intensified bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) regimen given in 14-day intervals (BEACOPP-14) with granulocyte colony-stimulating factor (G-CSF) support in advanced Hodgkin's lymphoma. PATIENTS AND METHODS: From July 1997 until March 2000, 94 patients with Hodgkin's lymphoma stage IIB, III, and IV were scheduled to receive eight cycles of BEACOPP-14. Consolidation radiotherapy was administered to regions with initial bulky disease or residual tumor after chemotherapy. RESULTS: All patients were assessable for toxicity and treatment outcome. Eighty-six patients received the planned eight cycles of BEACOPP-14. Consolidation radiotherapy was given in 66 patients. Chemotherapy could generally be administered on schedule. Dose reductions varied among drugs but were generally low. Acute toxicity was moderate, with World Health Organization grade 3/4 leukopenia in 75%, thrombocytopenia in 23%, anemia in 65%, and infection in 12% of patients. A total of 88 patients (94%) achieved a complete remission. Four patients had progressive disease. At a median observation time of 34 months, five patients have relapsed, one patient developed a secondary non-Hodgkin's lymphoma, and three deaths were documented. The overall survival and freedom from treatment failure rates at 34 months were 97% (95% confidence interval [CI], 93% to 100%) and 90% (95% CI, 84% to 97%), respectively. CONCLUSION: Acceleration of the BEACOPP baseline regimen by shortening cycle duration with G-CSF support is feasible and effective with moderate acute toxicity. On the basis of these results, the German Hodgkin's Lymphoma Study Group will compare the BEACOPP-14 regimen with BEACOPP-21 escalated in a prospective multicenter randomized trial.

Adolescent↗

[Secondary cranial extension after spinal anesthesia with isobaric 0.5% bupivacaine following postural change].

Inadvertent cranial extension of sympathetic and sensory block following posture change during spinal anaesthesia has been reported for isobaric as well as for hyperbaric local anaesthetics. We present the case of a patient who underwent surgical repair of a refracture of the tibia under spinal anaesthesia with 17.5 mg of isobaric 0.5% bupivacaine. The maximum level of sensory block (MLSB) reached T8 after 15 min. Following posture change into a 15 degrees anti-Trendelenburg position 35 min after lumbar puncture, the MLSB increased cranially for 10 segments and reached the C6 level after 10 min of anti-Trendelenburg position. The patient suffered from severe bradycardia and arterial hypotension which were treated with 6% hydroxyethyl starch, atropine and Akrinor. In addition, the patient developed respiratory insufficiency and was therefore intubated and the lungs were mechanically ventilated. The operation was performed uneventfully with the patient under general anaesthesia. At the end of surgery the trachea was extubated, and the patient was awake with stable hemodynamics, sufficient spontaneous ventilation and free of pain. MLSB reached the second lumbar dermatome. This case shows that after assumed fixation of the local anaesthetic an inadvertent extension of the MLSB following posture change is possible. Close surveillance is recommended for patients with central neuraxial blocks until the block is in complete remission. The mechanisms for inadvertent high extension of the MLSB following posture change are discussed.

Anesthesia, General↗

Antibodies to heat-shock protein 65 and neopterin levels in patients with type 1 diabetes mellitus.

Antibodies to heat shock protein (hsp) are strongly associated with atherosclerotic cardiovascular disease in the non-diabetic population as well as in patients with type 2 diabetes mellitus. In type 1 diabetes increased antibody titers to hsp were found to be a symptom of the autoimmune disease leading to beta-cell damage. We asked whether hsp antibody titers are related to metabolic control and late complications in type 1 diabetic patients. Serum neopterin, also an indicator of chronic inflammation, was also evaluated. The hsp65 antibody titer was determined in 138 patients with type 1 diabetes, 47 women and 91 men, aged 35.5 +/- 12 years with a mean diabetes duration of 16.6 +/- 10.5 years. A history of diabetic late complications and cardiovascular disease was taken. A fundoscopy and a neurological examination were performed, nephropathy was assessed by measurement of the urinary albumin excretion rate. For the measurement of the hsp antibody titer an enzyme-linked immunosorbent assay (ELISA) was applied, for neopterin a radio-immuno assay (RIA) was used. The hsp65 antibody titer was found to be positively related to the patients' age (r = 0.237; p < 0.035). Patients with retinopathy revealed significantly higher hsp65 antibody titers (307.2 +/- 38.6) than those without retinopathy (150.0 +/- 18.5;p < 0.003). No correlation was found between hsp antibody titer and metabolic control. Serum neopterin levels revealed a trend towards a positive relationship with diabetes duration (r = 0.205; p < 0.0539) and a significant correlation with serum cholesterol levels (r = 0.436; p < 0.001), but not with HbA1 c values. Our data add further information to the role of inflammatory markers in the development of diabetic microangiopathy.

Adult↗

Absent virtues: the poacher becomes gamekeeper.

Since its inception, bioethics' principled stance has been to argue against paternalism and elitism, and for an inclusive ethical perspective. But at least in North America, the growth of bioethics as a special area of applied ethics has created conflicts within the field itself. Those who, a generation earlier, argued against paternalism and for both professional and public accountability in medical decision making are now part of the decision making process. Too often, it is argued in this paper, their allegiance is to the employer, or to a view of medicine that is institutionally based. As a result, it is suggested by this review, medical ethicists have adopted the perspective that, in the early 1970s, they most criticised. The answer, it is argued here, is to revisit a lexicographical ordering of responsibility in bioethics, one that recognises professionals as individuals with responsibilities, as citizens with a public posture, and finally, as professionals involved in the process of medical decision making.

Attitude of Health Personnel↗

Surveillance scheme for occupational skin disease in the Saarland, FRG. First report from BKH-S.

Occupational skin disease (OSD) is a significant public health concern. To keep OSDs under surveillance, a register of OSDs (BKH-S) was implemented in 1999 in the Saarland, FRG. We conducted a population-based register study to analyse all initial reports of OSDs reported to the BKH-S. 336 cases were prospectively assessed from July 1999 to June 2001. In 78% (n = 263) of the cases an occupational cause for the skin disease was stated, 91% (n = 240) of which fell within 16 occupational groups. This is equivalent to 6.8 cases per 10,000 workers per year within these occupational groups. Notably, young age groups (median age 35 years) were affected with a female predominance. The most frequent final diagnosis was irritant contact dermatitis (75%) followed by allergic contact dermatitis (34%) and atopic dermatitis (19%). The overall prevalence of occupationally relevant delayed-type reactors was 21% and of immediate-type reactors 17%. Work-related delayed-type sensitizations to potassium dichromate (n = 8) and immediate-type sensitizations to natural rubber latex (n = 11) were the most frequently observed. Questionnaire results showed frequent occupational skin contact with wet work (59%), detergents (48%), and disinfectants (38%). The second valid surveillance scheme for OSD in the FRG has been introduced and can be made available for further analysis.

Adult↗

[Demand for environmental medical advice at public health offices: experiences in the district aachen public health office].

Since November, 1999 environmental medical advice is offered to interested citizens in the Aachen district at the District Aachen Public Health Office in cooperation with the outpatient unit of environmental medicine (UEM) of the Institute of Hygiene and Environmental Medicine of the University Hospital at Aachen, Germany. Advisory cases are documented in a data bank of Microsoft(R) Access 97. Until now, all advisory cases between November, 1999 and March, 2001 have been descriptively analysed. In this period, 34 personal and two telephonic advices were performed. The frequency of advisory activities is in the lower rang of published experiences in environmental medicine. Age distribution, more frequent advice utilization by women than by men and predominance of unspecific health disorders are comparable with published environmental medical experiences. However, in respect of suspected exposures, unspecific indoor-related environmental factors are predominant. In the past this was true for wood preservatives. Judgement about possible relationships between suspected environmental factors and health disorders or diseases was positive among 11.8 % of the persons seeking advice. This percentage is higher than published experiences which mostly show values below 10 %. It must be considered that this judgement depends primarily on the physician. Other reasons may be the too small number of advice seeking persons and selective influences. Furthermore, a definite judgement can be made only after environmental medical diagnostics (biological monitoring, local inspection, ambient monitoring) and differential diagnostics. Conspicuously, 76.5 % of the advisory cases had no contact to environmental medicine prior to the environmental medical advice at the Aachen District Public Health Office. This points to an information deficit about possibilities to clarify questions concerning environmental medicine in the population. In this context a regional guide on environmental medicine may be helpful. The environmental medical advice for citizens is an excellent example of a successful cooperation between a public health office and an university, which have different special experience in environmental hygiene and environmental medicine. This cooperation brings selectively citizens seeking for advice in environment-related health risks and disorders to practitioners specialised in environmental medicine.

Adolescent↗

Impact of n-3 fatty acid supplemented parenteral nutrition on haemostasis patterns after major abdominal surgery.

In various diseases n-3 fatty acids exert anti-inflammatory properties. These effects seem to be related to the uptake and incorporation of eicosapentaenoic acid (EPA) into the cellular substrate pool after dietary intake of EPA, which is contained in fish oils (FO). In the state of inflammation EPA is released to compete with arachidonic acid (AA) for metabolism at the cyclo-oxygenase and the 5-lipoxygenase level. The metabolites of EPA have less inflammatory and chemotactic potency than the substances derived from AA. In addition to positive effects, early studies pointed towards prolonged bleeding times after dietary intake of n-3 fatty acids. This study was undertaken to address the issue of potential coagulation disturbances associated with postoperative parenteral FO administration. This was a prospective, randomised, double blinded clinical trial, carried out in two operative intensive care units (13 and 16 beds) in a university hospital. Forty-four patients undergoing elective major abdominal surgery participated in the trial. Patients were randomly assigned to receive total parenteral nutrition (TPN) supplemented with either soybean oil (SO, Lipovenoess 10% PLR; 1.0 g/kgBW per day; n = 20) for five days or with a combination of FO and SO (FO, Omegaven; 0.2 g/kgBW per day plus SO, Lipovenoes 10% PLR; 0.8 g/kgBW per day, n = 24), respectively. Blood samples were taken preoperatively (day -1), prior to (day 1) during (days 2-5) and after TPN (day 6). The coagulation parameters thromboplastin time (Quick), activated partial thromboplastin time (aPTT), fibrinogen and antithrombin III were measured. To differentially assess activation levels of extrinsic and intrinsic coagulation pathway, factors VIIa and XIIa were quantified. Moreover platelet function was determined by resonance thrombography. Baseline values of coagulation and platelet function were comparable in both groups, but coagulation activity dropped after surgery. Over the observation period of 6 days, however, physiological levels were regained. No clinically significant differences were observed between the SO- and SO + FO- group. These findings suggest that infusion of fish oil in doses up to 0.2 g/kgBW per day is safe regarding coagulation and platelet function.

Aged↗

One principle and three fallacies of disability studies.

A question between John Harris and I is the degree to which lessons may be learned, and insights gained, from a life distinguished by physical differences. He argues it as the "aborting Beethoven fallacy", I insist on the evidence that what we learn from physical differences may be critical and life enhancing.

Abortion, Eugenic↗

Human phosphatidylethanolamine-binding protein facilitates heterotrimeric G protein-dependent signaling.

In this study we report that human phosphatidylethanolamine-binding protein (hPBP) facilitates heterotrimeric G protein-coupled signaling. In Xenopus laevis oocytes, coexpression of hPBP with human mu opioid receptor, human delta opioid receptor, or human somatostatin receptor 2 evoked an agonist-induced increase in potassium conductance of G protein-activated inwardly rectifying potassium channels. This activation of heterotrimeric G protein signaling in oocytes could also be elicited by injection of bacterially overexpressed and purified hPBP. Stimulatory effect was pertussis toxin-sensitive and present even in the absence of coexpressed receptors. Additionally, an increase in G protein-mediated inhibition of adenylate cyclase activity, measured by the inhibition of forskolin-mediated cAMP accumulation, could be detected in HEK293 and NIH3T3 cells after expression of hPBP and in Xenopus oocytes after injection of hPBP. As [(35)S]guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) binding to membranes prepared from hPBP-expressing cells was significantly elevated and recombinant hPBP dose-dependently stimulated [(35)S]GTPgammaS binding to native membranes, the results presented provide strong evidence that hPBP-induced effects are G protein-dependent. These data suggest a novel function of hPBP in regulating G protein and G protein-coupled receptor signaling in vivo.

3T3 Cells↗