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J Eckert

Publications and source records attributed to J Eckert.

At least 37 records · Page 2Linked to original sources
PubMed2001

Veterinary aspects of alveolar echinococcosis--a zoonosis of public health significance.

Human alveolar echinococcosis (AE), caused by the metacestode stage of Echinococcus multilocularis, is a serious zoonosis which caused up to 100% lethality in untreated patients before the 1970s, when modern methods of treatment were not yet established. AE occurs in large areas of the northern hemisphere mostly with low country-wide prevalences, but high prevalences of up to 4% have been reported from small population groups in highly endemic foci, e.g. from China. AE includes many veterinary aspects which are the topic of this review. Recent studies have shown that E. multilocularis has a wider geographic range than previously anticipated. There is evidence for growing populations of red foxes (Vulpes vulpes) in some areas, for increasing invasion of cities by foxes and also for establishment of the parasite cycle in urban areas. These and other factors may lead to an increased infection risk for humans. Significant progress has been made in the development of sensitive and specific new techniques for the intra vitam and post mortem diagnosis of intestinal E. multilocularis infection in definitive hosts, notably the detection of coproantigen by enzyme-linked immunosorbent assay and of copro-DNA by PCR. Both tests can also be used for the identification of E. multilocularis in faecal samples collected in the environment. Recommendations are given for chemotherapy and chemoprophylaxis of the intestinal infection in definitive hosts. In recent years, infections with the metacestode stage of E. multilocularis have not only been diagnosed in humans in several regions, including at least eight countries in central Europe, but also in animal species which do not play a role in the transmission cycle (wild and domestic pigs, dogs etc.). From 1987 to 2000 our group in Zurich has diagnosed 10 cases of AE in dogs and 15 in captive monkeys. In 2 dogs, concurrent infections of the intestine and of the liver with adult and larval stages of E. multilocularis, respectively, were observed for the first time. Clinical data are presented, and methods of diagnosis and treatment (surgery, chemotherapy) are described. Furthermore, small liver lesions caused by E. multilocularis were diagnosed in 10% of 90 slaughter pigs, and 2.9% of 522 breeding sows had specific serum antibodies against parasite antigens. In view of the unpredictable epidemiological situation, all possible measures for preventing E. multilocularis infections in humans and in domestic animals should be initiated by the veterinary and health authorities.

Animals↗
PubMed2001

Topological-histological investigation of the pterygium.

BACKGROUND: It is a wide-spread assumption, never proven scientifically, that the pterygium is a duplication of the conjunctiva, with an intervening gap at the limbus. We therefore conducted a histological reinvestigation, primarily to clarify the topological relation between normal bulbar tissue and lesion. METHODS: Excised pterygia were prepared for light microscopy and embedding in paraffin. Two pterygia were serially sectioned, and samples of 49 others were removed, sectioned and stained (stains: H&E, alcian blue, toluidine blue, PAS; antibody: cytokeratin 18). RESULTS: The pterygium is an epithelium-covered protuberance of connective tissue, projecting over the normal surface of the eyeball; it consists of a base, which extends in the direction of growth, and lateral lobes. It is therefore impossible to insert a probe all the way under a pterygium. The bulbar tissue adjacent to the pterygial protuberance can likewise be histologically altered. That is, a narrow layer of connective tissue, well supplied with capillaries, may be present in the corneal section of the pterygium between Bowman's layer and the epithelium. CONCLUSION: Histological alterations of the stroma predominate quantitatively over those of the epithelium. The topographical anatomy of the lesion and the fact that bulbar tissue is modified along with the pterygium should be taken into account when excision is undertaken. We predict that if all the altered tissue is removed, the rate of recurrence will be reduced.

Aged↗
PubMed2001

Catalysis research of relevance to carbon management: progress, challenges, and opportunities.

The goal of the "Opportunities for Catalysis Research in Carbon Management" workshop was to review within the context of greenhouse gas/carbon issues the current state of knowledge, barriers to further scientific and technological progress, and basic scientific research needs in the areas of H2 generation and utilization, light hydrocarbon activation and utilization, carbon dioxide activation, utilization, and sequestration, emerging techniques and research directions in relevant catalysis research, and in catalysis for more efficient transportation engines. Several overarching themes emerge from this review. First and foremost, there is a pressing need to better understand in detail the catalytic mechanisms involved in almost every process area mentioned above. This includes the structures, energetics, lifetimes, and reactivities of the species thought to be important in the key catalytic cycles. As much of this type of information as is possible to acquire would also greatly aid in better understanding perplexing, incomplete/inefficient catalytic cycles and in inventing new, efficient ones. The most productive way to attack such problems must include long-term, in-depth fundamental studies of both commercial and model processes, by conventional research techniques and, importantly, by applying various promising new physicochemical and computational approaches which would allow incisive, in situ elucidation of reaction pathways. There is also a consensus that more exploratory experiments, especially high-risk, unconventional catalytic and model studies, should be undertaken. Such an effort will likely require specialized equipment, instrumentation, and computational facilities. The most expeditious and cost-effective means to carry out this research would be by close coupling of academic, industrial, and national laboratory catalysis efforts worldwide. Completely new research approaches should be vigorously explored, ranging from novel compositions, fabrication techniques, reactors, and reaction conditions for heterogeneous catalysts, to novel ligands and ligation geometries (e.g., biomimetic), reaction media, and activation methods for homogeneous ones. The interplay between these two areas involving various hybrid and single-site supported catalyst systems should also be productive. Finally, new combinatorial and semicombinatorial means to rapidly create and screen catalyst systems are now available. As a complement to the approaches noted above, these techniques promise to greatly accelerate catalyst discovery, evaluation, and understanding. They should be incorporated in the vigorous international research effort needed in this field.

Journal Article↗
PubMed2000

WAAVP/Pfizer award for excellence in teaching veterinary parasitology: teaching of veterinary parasitology--quo vadis?

Some thoughts on training and recruitment of academic teachers and future trends in teaching veterinary parasitology are presented with emphasis on the European situation. It is underlined that research is an indispensable basis for academic teaching. Besides a broad scientific background of the teacher, motivation and teaching methods are also important. Many academic teachers do not receive formal training in teaching methods. In order to improve future education, training of staff members in teaching methods should be promoted. Quality control of teaching and research, already established in many schools, should generally be introduced. Teaching is mostly underestimated in relation to research. Therefore, more weight should be placed on the former both in selecting scientists for the career as academic teachers and in evaluating and ranking departments for their academic activities. In the future veterinary medicine will have to cope with profound changes in the society and the veterinary profession, and the progressing European unification will enhance trends for internationalizing teaching curricula. Therefore, veterinary medicine has to reconsider the teaching subjects and methods and to lay more emphasis on flexibility, skills of problem-solving and self-learning and on training for life-long learning. At present there is an ongoing discussion on the question how to teach veterinary medicine, including veterinary parasitology. There are various options, and some of them are discussed, namely, the disciplinary and the problem-based/organ-focussed approaches. It is concluded that for teaching of veterinary parasitology and related disciplines a combined disciplinary and problem-based approach offers the best chances for fulfilling the requirements of teaching for the future. In the curriculum of undergraduate teaching of veterinary medicine at least 70-90 h should be dedicated to veterinary parasitology using a disciplinary and taxonomic approach. Additional hours are required for instructions on clinical cases in approaches focussed on animal species and/or organ diseases. As there is a need for discussing teaching issues, post-graduate specialization, and continuing education in parasitology and related disciplines on national and international levels, it is recommended to WAAVP to include regular workshops on teaching in the programmes of the biannual conferences, and to establish a permanent committee which should collect information and submit proposals for improvement of teaching veterinary parasitology.

Animals↗
PubMed2000

Echinococcosis: an emerging or re-emerging zoonosis?

The aim of this review is a critical discussion of factors actually or potentially contributing to persistence or emergence of echinococcosis in humans. Alveolar echinococcosis (AE), a life-threatening infection of humans, is caused by a larval stage of Echinococcus multilocularis. The adult parasite inhabits the intestine of foxes and other carnivores and has a wide distribution in the northern hemisphere (North America and northern and central Eurasia). Recent surveys in central Europe have extended the known geographical occurrence of E. multilocularis in foxes from four countries at the end of the 1980s to at least 11 countries in 1999. Cases of human AE previously regularly reported from only four countries are now recorded from seven countries, but the annual incidences are low. Since adequate information from earlier surveys is not available, it is not possible to conclude if the new findings reflect a recent extension of the parasite's range or just the first identification of hitherto unnoticed endemic areas. Evidence of parasite spreading has been reported from North America and Japan. Factors with the potential of enhancing the infection risk for humans in the future include increasing fox populations and parasite prevalences, progressing invasion of cities by foxes, the establishment of urban cycles of the parasite, and the spill-over of the E. multilocularis infection from wild carnivores to domestic dogs and cats. In view of the potential severity and fatality of AE in humans health authorities should initiate internationally coordinated countermeasures. Although control programmes against human cystic echinococcosis (CE), caused by E. granulosus, have been established in some countries and effective control strategies are available, the parasite has still a wide geographical distribution affecting many countries of all continents. Thus, human CE is persisting in many parts of the world with high incidences, and in some areas it is a re-emerging problem. For example, alarming increases of the number of human cases have been reported from Bulgaria and Kazakhstan, and the People's Republic of China. Progress in control can only be expected if health authorities attribute a higher priority to this disease and if all modern diagnostic and control options (for example vaccination of intermediate host animals) can be used.

Adult↗
PubMed2000

The "galloping" history of intermittent claudication.

Intermittent claudication (IC) due to arterial occlusive disease was first diagnosed by the French veterinary surgeon Jean-François Bouley jeune in a horse drawing a cabriolet in the streets of Paris as early as 1831. The animal was repeatedly exercised and always started to limp with the hind legs at similar work loads. Autopsy revealed partially thrombosed aneurysm of the abdominal aorta and occlusions of both femoral arteries which were correctly identified as the cause of IC. In 1858 the famous neurologist Jean-Martin Charcot working at the Salpêtrière in Paris first discovered the condition in a patient, who was wounded by a bullet during the conquest of Algery and developed iliac artery aneurysm obliterated by a thrombus. He was aware of the first description in veterinary medicine. In Germany IC was also first mentioned in horses (Rademacher, 1838). 13 reports of patients were contributed by the neurologist Heinrich Erb in 1898 and 1904. Some interesting features of the phenomenon of IC like the amount of exercise necessary to provoke it, localization, social relevance, prolongation of the Achilles tendon reflex, decrease of maximal plantar flexion force of the foot and production of "Lewis factor p" are summarized. In human patients arteriosclerosis is the well recognized principal cause of arterial obstructions, in horses, however, the lesions are due to infection by the roundworm Strongylus vulgaris. In the fascinating life cycle the larvae migrate into the intima of small and large arteries and provoke aneurysms and intravascular thrombosis.

Animals↗
PubMed2000

Evidence for a parasite-mediated inhibition of abomasal acid secretion in sheep infected with Ostertagia leptospicularis.

The acid secretory capacity of the abomasal mucosa was studied in sheep experimentally infected with Ostertagia leptospicularis. The acidity of the abomasal contents, permanently recorded by a pH probe located inside the abomasum, decreased markedly to mean levels between pH 5 and 6. Subcutaneous administration of histamine or carbachol successfully stimulated acid secretion (pH 3.4). The results indicate that the abomasal mucosa harboured a population of functional parietal cells which were also identified immunohistochemically (H(+)/K(+)-ATPase). Ultrastructural investigation before stimulation revealed that the majority of these cells was in a resting state. Despite high serum gastrin levels, the acid secretion was blocked either at the level of the parietal cell or the enterochromaffin-like cell by an unknown factor, possibly mediated by the parasites. This is the first report of a parietal cell dysfunction associated with a nematode infection in the abomasum. It is suggested that the parasites induce changes in their environment which favour their survival and/or increase their reproduction.

Abomasum↗
PubMed2000

Use of CT scan in the diagnosis of pediatric acute appendicitis.

BACKGROUND: The efficacy of CT scan in the diagnosis of pediatric appendicitis has hot been established. METHODS: Every patient under the age of 18 who was diagnosed and treated for acute appendicitis in the 1 year period from March 1998-March 1999 at Lakeland Regional Medical Center were included. The presentation, laboratory evaluation, imaging evaluation, hospital course, and pathologic evaluation were reviewed. Selected imaging studies were reviewed by an independent radiologist. RESULTS: Forty-six patients were treated for appendicitis; 17 of them received CT scans (37%). The CT scans predicted appendicitis in 9 of 17 cases (sensitivity = 53%). False-negative studies resulted in some morbidity but no mortality. The radiology review indicated that three cases clearly did not demonstrate appendicitis. The other false-negative studies were secondary to either technical or professional factors. CONCLUSION: The efficacy of CT imaging in the diagnosis of acute appendicitis in children has still not been demonstrated. This limited series indicates that if CT scanning is to be used in pediatric patients, more attention to technical and professional factors may be required. Some of these factors, particularly the ingestion of oral contrast, are particularly problematic in small children and may limit the effectiveness of this modality.

Adolescent↗
PubMed1999

[Swiss study of chemotherapy of alveolar echinococcosis--review of a 20-year clinical research project].

Alveolar echinococcosis (A. E.), caused by Echinococcus multilocularis, behaves biologically like a malignant tumour of the liver which is best treated by radical surgery. However, radical surgery can be performed only in about 20-30% of A. E. cases. The efficacy of chemotherapy with benzimidazole derivatives for inoperable cases is debated. The results of a prospective Swiss chemotherapy trial, which started in 1976, are reviewed. In the last 20 years a total of 110 patients has been included in our protocol and 74 of these patients had inoperable or palliatively operated A. E. (average observation time 12.8 years). The efficacy of long-term chemotherapy was documented by increase of 10-year survival compared to historical (untreated) A. E. cases (80 vs 6%) and by reduction or stabilisation of the liver lesions in 83% of cases during long-term chemotherapy. Several relevant problems remain to be clarified, e.g. optimal duration of chemotherapy, the controversy as to whether chemotherapy is parasitostatic or parasitocidal, the establishment of reliable routine methods for short-term assessment of therapeutic efficacy, and comparative studies between mebendazole and albendazole. Furthermore, additional studies are necessary in collaboration with basic science, for example on the impact of the increasing fox population, with invasion of large agglomerations, on infection risk in the Swiss population, and the importance of individual immune competence for susceptibility or resistance to A. E.

Albendazole↗
PubMed1999

Catatonia as a psychomotor syndrome: a rating scale and extrapyramidal motor symptoms.

BACKGROUND: Catatonia was first described by Kahlbaum as a psychomotor disease with motor, behavioral, and affective symptoms. In keeping with this concept, we developed a rating scale for catatonia (Northoff Catatonia Scale [NCS]) with three different categories of symptoms (i.e., motor, behavioral, affective). Furthermore, the question of the relationship among catatonic symptoms, extrapyramidal motor symptoms, and neuroleptics was addressed in the present study. METHOD: 34 acute catatonic patients and 68 age-, sex-, diagnosis-, and medication-matched psychiatric control subjects were investigated on days 0, 1, 3, 7, and 21 with the NCS, with other already validated catatonia rating scales by Rosebush, Bush (BFCRS), and Rogers (MRS), as well as with scales for hypokinetic (SEPS) and dyskinetic (AIMS) extrapyramidal motor features. Validity and reliability of the new scale, factor analysis, correlational analysis, and differences between catatonic patients and psychiatric control subjects were statistically calculated. RESULTS: NCS showed high validity (i.e., significant positive correlations [p <0.0001] with the other scales, significant differences between catatonic and control subjects), high intra-and interrater reliabilities (r = 0.80-0.96), and high affective subscores. Factor analysis revealed four factors best characterized as affective, hypoactive, hyperactive, and behavioral. Catatonic scores in NCS correlated significantly with AIMS on day 0 and SEPS on days 7 and 21. There were no significant differences in catatonic (i.e., NCS, MRS, BFCRS) and extrapyramidal (i.e., AIMS, SEPS) scores between neuroleptically treated and untreated catatonic subjects. CONCLUSIONS: The following conclusions were drawn: (1) the NCS has to be considered as a valid and reliable rating instrument for catatonia; (2) catatonia can be characterized by psychomotor symptoms encompassing motor, affective, and behavioral alterations; and (3) extrapyramidal hyperkinesias like dyskinesias are apparently closely related to catatonic symptoms which, in general, seem to be relatively independent of previous neuroleptic medication.

Acute Disease↗
PubMed1999

Alveolar echinococcosis in humans: the current situation in Central Europe and the need for countermeasures.

Alveolar echinococcosis (AE) in humans is caused by a larval stage (metacestode) of Echinococcus multilocularis, which exhibits a tumor-like growth, initially in the liver, with the potential to induce serious disease. At the end of the 1980s, E. multilocularis was known to occur in four countries of Central Europe, but has now been identified in ten countries. Red foxes are the principal definitive hosts of E. multilocularis and sources of human infection, but dogs and cats can also be infected. Growing populations of foxes and their increasing immigration to urban areas are new risk factors. Human AE is rare but its potential high fatality rate, considerable costs of treatment and the persisting infection risk should be reasons for health authorities in European countries to establish coordinated systems of surveillance and risk assessment in combination with measures to reduce morbidity and mortality of AE in the human population. Here, J. Eckert and P. Deplazes outline the current epidemiological situation in Central Europe, and discuss options for surveillance, prevention and control.

Animals↗
PubMed1999

Reduced activation and altered laterality in two neuroleptic-naive catatonic patients during a motor task in functional MRI.

BACKGROUND: Catatonia, a symptom complex with motor, affective and cognitive symptoms seen in a variety of psychotic conditions and with organic disease, was examined using a motor task using functional magnetic resonance imaging (fMRI). METHODS: Two acute catatonic patients and two age- and sex-matched healthy controls performed sequential finger opposition (SFO) after being medicated with 2 mg of lorazepam (i.v.). Functional magnetic resonance images were collected using a gradient echo pulse sequence (EPI). RESULTS: Patients with catatonia showed reduced motor activation of the contralateral motor cortex during SFO of the right hand, ipsilateral activation was similar for patients and controls. There were no differences in the activation of the SMA. During left hand activation the right-handed catatonic patients showed more activation in the ipsilateral cortex, a reversal from the normal pattern of activation in which the contralateral side shows four to five times more activation than the ipsilateral side. CONCLUSIONS: In catatonic patients there is a decreased activation in motor cortex during a motor task compared to matched medicated healthy controls. In addition activation of the non-dominant side, left-handed activity in right-handed patients, results in a total reversal of the normal pattern of lateral activation suggesting a disturbance in hemispheric localization of activity during a catatonic state.

Acute Disease↗
PubMed1999

Echinococcus multilocularis coproantigen detection by enzyme-linked immunosorbent assay in fox, dog, and cat populations.

A sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of Echinococcus multilocularis coproantigens (EM-ELISA) was developed with polyclonal rabbit (solid phase) and chicken egg (catching) antibodies that were directed against E. multilocularis coproantigens and somatic worm antigens, respectively. In experimentally infected dogs and cats, coproantigens were first detectable 6-17 days postinfection (PI) in samples of 8 dogs (worm burdens at necropsy: 6,330-43,200) and from 11 days PI onward in samples of 5 cats infected with 20-6,833 worms. After anthelmintic treatment of 4 dogs and 5 cats at day 20 PI, coproantigen excretion disappeared within 3-5 days. The sensitivity of the ELISA was 83.6% in 55 foxes infected with 4-60,000 E. multilocularis, but reached 93.3% in the 45 foxes harboring more than 20 worms. The EM-ELISA was used in surveys of "normal" dog and cat populations in Switzerland. Among 660 dogs and 263 cats, 5 dogs and 2 cats exhibited a positive reaction. In 2 of these dogs (0.30%) and 1 cat (0.38%), intestinal E. multilocularis infections were confirmed by necropsy, polymerase chain reaction PCR, or both. The specificites of the ELISA in these groups were found to be 99.5% and 99.6%, respectively, if positive ELISA results that could not be confirmed by other methods were classified as "false positive" reactions.

Animals↗
PubMed1999

[Epidemiological studies on Echinococcus multilocularis in red foxes in north-west Poland].

The studies were carried out in 15 provinces of North-West part of Poland in the years 1994 - 1997 under a regime of strict laboratory safety regulation. The intestine of 1909 red foxes were examined for the presence of Echinococcus multilocularis according to the method of Eckert et al (1991). The intestines were divided finto four to six sections and fifteen smears were prepared from each animal under study. Foxes infected with E. multilocularis were detected in 8 provinces. The average prevalence rate in these provinces was 1.20 per cent. Of special interest fis the finding in Slupsk and Gdafisk regions, where 9.6 per cent of foxes were infected with E. multilocularis. In comparison with some other European endemic regions the prevalence rates of E. multilocularis in Poland was low, except for the Stupsk-Gdańsk area.

Animals↗
PubMed1999

[Studies on the incidence of echinococcus multilocularis in red foxes (Vulpes vulpes) in north-east, central and south of Poland].

During the year 1994-1997, a total number of 1042 red foxes orginating from the 33 provinces North-East, Central and South of Poland under special safety procautions for intestinal stages of Echinococcus multilocularis using the mucosal-smer technique were examined. An average of 5.09% (53 foxes) from 10 provinces was infected. In those provinces, the prevalance varied between 1.19% to 35.71%. The infection varied from low to very high but mostly harboured gravid E. multilocularis parasites with thick-shelled eggs. Our data indicate that E. multilocularis in foxes has a surprisingly wide distribution in Poland. These new epidemiological data indicate that a potential risk of infection for humans may exists in all areas where foxes infected with E. multilocularis have been identified. It has been assumed that E. multilocularis might also occur in other provinces in which foxes examination have not yet been undertaken or number examined of animals was low. This study was supported by a two grands from the Swiss National Foundation (projects No 7PLPJ038414 and 7PLPJ041302).

Animals↗
PubMed1998

Canine leishmaniosis in Cyprus due to Leishmania infantum MON 1.

During a serological survey in 1996, a total of 601 dogs (group I) distributed all over the government controlled southern area of Cyprus was examined using an enzyme-linked immunosorbent assay (ELISA) for the presence of specific antibodies directed against soluble antigens of promastigote stages of Leishmania infantum. The overall seroprevalence rate in this group was 1.7%. A second group (group II) of dogs was selected from regions where seropositive dogs where determined within the first group. In group II specific anti-Leishmania antibodies could be detected in 30 of 301 dogs investigated (10%). The highest seroprevalence rates were found in the regions of Agios Georgios (26.2%) and Limnatis (12.2%). Ten parasite isolates from ten dogs (six with typical symptoms of canine leishmaniosis and four without symptoms) originating from five locations could be characterised by zymodeme analysis. All ten isolates were identified as L. infantum zymodeme MON 1.

Animals↗