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K Fleischer

Publications and source records attributed to K Fleischer.

At least 19 recordsLinked to original sources
PubMed2003

Hydrogen local vibrational modes in zinc oxide.

Using Raman backscattering spectroscopy we have observed six local vibrational modes in as-grown state-of-the-art nominally undoped zinc oxide single crystals. The local vibrational modes are located at nu=2854, 2890, 2918, 2948, 2988, and 3096 cm(-1). Some specimens were annealed up to 950 degrees C to remove hydrogen. A subsequent Raman backscattering measurement revealed that the local vibrational modes disappeared. This establishes that the observed local vibrational modes are caused by the presence of hydrogen in the ZnO crystals.

Journal Article↗
PubMed2003

Age as a risk factor for severe manifestations and fatal outcome of falciparum malaria in European patients: observations from TropNetEurop and SIMPID Surveillance Data.

Previous studies have indicated that age is a risk factor for severe falciparum malaria in nonimmune patients. The objectives of this study were to reevaluate previous findings with a larger sample and to find out how strongly clinical outcomes for elderly patients differ from those for younger patients. Results of adjusted analyses indicated that the risks of death due to falciparum malaria, of experiencing cerebral or severe disease in general, and of hospitalization increased significantly with each decade of life. The case-fatality rate was almost 6 times greater among elderly patients than among younger patients, and cerebral complications occurred 3 times more often among elderly patients. Antimalarial chemoprophylaxis was significantly associated with a lower case-fatality rate and a lower frequency of cerebral complications. Women were more susceptible to cerebral complications than were men. Our study provides evidence that falciparum malaria is more serious in older patients and demonstrates that clinical surveillance networks are capable of providing quality data for investigation of rare events or diseases.

Age Factors↗
PubMed2003

[Old age as risk factor for complications of malaria in non-immune travellers].

BACKGROUND: Malaria plays an important role as a dangerous imported infection in Europe. In addition, the number of elderly travellers is increasing. We examined the hypothesis, whether age can be considered as a risk factor for the development of complications in malaria. PATIENTS AND METHODS: We examined retrospectively 134 case records of patients of all age groups with a plasmodial infection. We analysed personal data, travel details and patient histories, the neurological status, respiratory function, as well as haematological, biochemical and parasitological parameters. RESULTS: There is significant evidence for a correlation between age and the frequency of complications in malaria like cerebral involvement, respiratory failure, renal failure, anaemia, and hyperparasitaemia. Out of 132 patients over 15 years of age, 49 (37.1 %) developed a severe course of malaria. In the age group of 60 years and above this percentage increased to 61.5 %. The age distribution in the group with severe malaria was significantly shifted towards the elderly (p = 0.016 in Mann-Whitney test). The duration of hospitalisation also increased with age from an average of five days for the group below 45 years to 21 days for the elderly of 60 years and above. CONCLUSION: Our findings suggest a higher risk for a severe course of malaria in the elderly. For this reason, extensive advice on the correct use of exposure- and chemoprophylaxis of malaria is especially important for travellers above the age of 60.

Adolescent↗
PubMed2002

Epidemiology and clinical features of imported dengue fever in Europe: sentinel surveillance data from TropNetEurop.

Travelers have the potential both to acquire and to spread dengue virus infection. The incidence of dengue fever (DF) among European travelers certainly is underestimated, because few centers use standardized diagnostic procedures for febrile patients. In addition, DF is currently not reported in most European public health systems. Surveillance has commenced within the framework of a European Network on Imported Infectious Disease Surveillance (TropNetEurop) to gain information on the quantity and severity of cases of dengue imported into Europe. Descriptions of 294 patients with DF were analyzed for epidemiological information and clinical features. By far the most infections were imported from Asia, which suggests a high risk of DF for travelers to that region. Dengue hemorrhagic fever occurred in 7 patients (2.4%) all of whom recovered. Data reported by member sites of the TropNetEurop can contribute to understanding the epidemiology and clinical characteristics of imported DF.

Adolescent↗
PubMed2002

Imported Falciparum malaria in Europe: sentinel surveillance data from the European network on surveillance of imported infectious diseases.

Malaria continues to have a high morbidity rate associated among European travelers. Thorough recording of epidemiological and clinical aspects of imported malaria has been helpful in the detection of new outbreaks and areas of developing drug resistance. Sentinel surveillance of data collected prospectively since 1999 has begun within TropNetEurop, a European network focusing on imported infectious diseases. TropNetEurop appears to cover approximately 10% of all patients with malaria seen in Europe. Reports of 1659 immigrants and European patients with Plasmodium falciparum malaria were analyzed for epidemiological information and data on clinical features. Regional data were quite diverse, reflecting local patterns of immigration and international travel. By far, the most infections were imported from West Africa. Europeans had more clinical complications; consequently, all deaths occurred in this group. Compared with European standards, the mortality rate was low (0.6% in Europeans). Data from TropNetEurop member sites can contribute to our understanding of the epidemiological and clinical findings regarding imported falciparum malaria.

Adolescent↗
PubMed2001

[What is effective in traveler's diarrhea? Current recommendations on prevention, therapy and after care].

Traveller's diarrhea is almost always due to an infection with intestinal bacteria, viruses or parasites. The leading agents are the ubiquitous enterotoxic E. coli bacteria. Prophylaxis is achieved primarily by the strict avoidance of fecally contaminated food and drink--advice which, however, is often ignored. Chemoprophylactic measures include the use of probiotics, in particular Saccharomyces boulardii, with antibiotics being given only in special cases. Treatment consists mainly in the replacement of lost fluids and electrolytes in the form of oral rehydration solutions. Second-line treatment includes probiotics and antimotility agents such as loperamide. Antibiotics (quinolones) should be reserved for severe febrile forms of the condition.

Diarrhea↗
PubMed2001

[Direct thrombin antagonists].

BACKGROUND: Inhibiting thrombin as a key enzyme of the coagulation cascade is therapeutically useful in thromboembolic diseases. In coronary thrombosis, direct thrombin inhibitors promise to be useful for an efficacious therapy. Hirudin and recombinant or synthetic mimetics like hirulog, argatroban and melagatran have proven their efficacy in clinical studies. CONCLUSION: Therapy with direct thrombin inhibitors such as hirudin and analogous substances reduces coronary events. Moreover, the agents are useful for therapy of thromboembolic diseases, especially in the case of heparin induced thrombocytopenia type II.

Acute Disease↗
PubMed2000

[Lassa fever].

UNLABELLED: A 22-year-old female German student was admitted with fever of unknown origin for 5 days to the hospital of her hometown immediately after returning from a 7-week journey under simple conditions through 4 West African countries. After exclusion of malaria and typhoid and nonrespondence to antibiosis, she was transferred on the 4th day to the Department of Tropical Medicine in Würzburg. After the clinical assumption of Lassa fever, the virus was confirmed by PCR within 3 hours (Bernhard Nocht Institute, Hamburg) on the 10th day of her illness. The assumption was based on travel history, continuous fever, cough, pharyngitis, thoracic pain, and exclusion of other acute infections. From the beginning, the patient was cared for with barrier nursing and after diagnosis under strict isolation in an intensive care unit reserved for her alone by a team of doctors and nurses specialized in tropical medicine and intensive care. The staff was protected through isolation suits with filters. Monitoring and therapy entailed all methods of intensive care and intravenous administration of ribavirin 16 mg/kg body weight = 900 mg every 6 hours. The patient died on the 14th day of her illness in a volume deficiency shock due to uncontrollable heavy hemorrhage from all organs including the skin, a so-called "leakage syndrome". CONCLUSION: Conclusions are drawn regarding training in tropical medicine, diagnostics of highly contagious infections, intensive care of patients affected with them under isolation, contact tracing, psychological crisis intervention for personnel, media information, care of the infectious corpse and disposal of infectious waste.

Adult↗
PubMed1998

[A patient with muscle pain after a journey to the tropics. Myocardial involvement in proximal myotonic myopathy].

HISTORY AND ADMISSION FINDINGS: A 36-year-old man reported feeling generally unwell and experiencing shooting and tearing pain, especially in the thighs and over the precordium, just after returning from a five-week holiday in Central Africa. An active sportsman in his youth (fencing) he was known to have incomplete right bundle branch block in the ECG and a raised concentration of gamma-glutamyl transferase, of unknown aetiology. Physical examination on admission was negative except for discrete weakness on head bending and slightly delayed finger stretching after making a fist. INVESTIGATIONS: Multiple tests excluded tropical diseases. There were abnormal T waves in leads III and V1 of the ECG. Serum concentrations of creatine kinase (CK; maximally 822 U/l), gamma-glutamyl transaminase (gamma-GT; 446 U/l), glutamyl-pyruvate transaminase (GPT; 510 U/l) and of glutamate-oxalate transaminase (GOT; 108 U/l) were all elevated. Erythrocyte sedimentation rate and C-reactive protein were within normal limits. TREATMENT AND COURSE: At first the suspected diagnosis was myocarditis and he was placed on bed-rest, monitored and treated symptomatically. Because the levels of CK, gamma-GT, GPT and GOT improved only transiently, there were no signs of inflammatory disease and the muscle pains continued, biopsies of skeletal muscle and the liver were done. They revealed nonspecific liver changes and a noninflammatory myopathy. As congenital myopathy was suspected he was transferred to the neurology department where the diagnosis of proximal myotonic myopathy (PROMM) was established. CONCLUSION: We assume that an unknown viral infection triggered the illness that, in addition to the usual nonspecific symptoms, accentuated the signs of the existing multi-system proximal myotonic myopathy.

Adult↗
PubMed1997

Exchange blood transfusion in severe falciparum malaria: retrospective evaluation of 61 patients treated with, compared to 63 patients treated without, exchange transfusion.

The rationale for exchange blood transfusion (ET) in severe falciparum malaria is threefold: reduction of parasitaemia, reduction of presumptive 'toxic' factors, and improvement of the rheological quality of the blood. We evaluated the records of 61 patients treated with ET to describe the present status of malaria treatment in Germany, Austria and Switzerland and to assess the efficacy of ET. Clinical data of 61 patients treated with ET were compared to data of 63 patients treated in 2 hospitals where ETs were generally not performed. We found that exchange transfusion is applied according to the clinician's subjective impression rather than strict guidelines. Logistic regression analysis adjusting for the differences in clinical parameters between patients treated with or without ET did not identify treatment as a prognostic indicator (odds ratio for relative risk of death with ET: 1.3; 95% CI: 0.4-4.9). Exchange transfusion did not significantly improve the unfavourable prognosis in cases of severe falciparum malaria. However, failure to reach statistical significance may be due to the retrospective design of the study and therefore non-systematic approach.

Adult↗
PubMed1997

Selective endothelial dysfunction in conscious dogs after cardiopulmonary bypass.

It has previously been demonstrated that cardiopulmonary bypass (CPB) causes prolonged pulmonary vascular hyperreactivity (D.P. Nyhan, J.M. Redmond, A.M. Gillinov, K. Nishiwaki, and P.A. Murray. J. Appl. Physiol. 77: 1584-1590, 1994). This study investigated the effects of CPB on endothelium-dependent (acetylcholine and bradykinin) and endothelium-independent (sodium nitroprusside) pulmonary vasodilation in conscious dogs. Continuous left pulmonary vascular pressure-flow (LP-Q) plots were generated in conscious dogs before CPB and again in the same animals 3-4 days post-CPB. The dose of U-46619 used to acutely preconstrict the pulmonary circulation to similar levels pre- and post-CPB was decreased (0.13 +/- 0.01 vs. 0.10 +/- 0.01 mg.kg-1.min-1, P < 0.01) after CPB. Acetylcholine, bradykinin, and sodium nitroprusside all caused dose-dependent pulmonary vasodilation pre-CPB. The pulmonary vasodilator response to acetylcholine was completely abolished post-CPB. For example, at left pulmonary blood flow of 80 ml.kg-1.min-1 acetylcholine (10 micrograms.kg-1.min-1) resulted in 72 +/- 15% reversal (P < 0.01) of U-46619 preconstriction pre-CPB but caused no change post-CPB. However, the responses to bradykinin and sodium nitroprusside were unchanged post-CPB. The impaired pulmonary vasodilator response to acetylcholine, but not to bradykinin, suggests a selective endothelial defect post-CPB. The normal response to sodium nitroprusside indicates that cGMP-mediated vasodilation is unchanged post-CPB.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗