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G Stanek

Publications and source records attributed to G Stanek.

At least 19 recordsLinked to original sources

The elephant knee joint: morphological and biomechanical considerations.

Elephant limbs display unique morphological features which are related mainly to supporting the enormous body weight of the animal. In elephants, the knee joint plays important roles in weight bearing and locomotion, but anatomical data are sparse and lacking in functional analyses. In addition, the knee joint is affected frequently by arthrosis. Here we examined structures of the knee joint by means of standard anatomical techniques in eight African (Loxodonta africana) and three Asian elephants (Elephas maximus). Furthermore, we performed radiography in five African and two Asian elephants and magnetic resonance imaging (MRI) in one African elephant. Macerated bones of 11 individuals (four African, seven Asian elephants) were measured with a pair of callipers to give standardized measurements of the articular parts. In one Asian and three African elephants, kinematic and functional analyses were carried out using a digitizer and according to the helical axis concept. Some peculiarities of healthy and arthrotic knee joints of elephants were compared with human knees. In contrast to those of other quadruped mammals, the knee joint of elephants displays an extended resting position. The femorotibial joint of elephants shows a high grade of congruency and the menisci are extremely narrow and thin. The four-bar mechanism of the cruciate ligaments exists also in the elephant. The main motion of the knee joint is extension-flexion with a range of motion of 142 degrees . In elephants, arthrotic alterations of the knee joint can lead to injury or loss of the cranial (anterior) cruciate ligament.

Animals↗

The role of Chlamydia pneumoniae in human aortic disease-a hypothesis revisited.

BACKGROUND: The role of Chlamydia pneumoniae in the pathogenesis of aortic aneurysm is controversial. We investigated the presence of C. pneumoniae in tissue samples excised from patients and controls. METHODS: Aortic wall specimens were obtained from 17 patients with acute Stanford type A aortic dissection, 25 patients with thoracic aortic aneurysms (TAA) and 23 patients with abdominal aortic aneurysms (AAA). Eighty-three tissue samples of 73 control patients free of aortic disease were obtained either at surgery or autopsy. The presence of Chlamydia subspecies DNA (sequences specific for all known Chlamydiaceae) and DNA of C. pneumoniae, C. trachomatis and C. psittaci were assessed by a validated highly sensitive and specific real time polymerase chain reaction (PCR) analysis. Atherosclerotic risk factors were assessed in all patients. RESULTS: We failed to detect C. pneumoniae and C. psittaci-DNA in any of the 148 vessel specimens. C. trachomatis-DNA was detected in 1/65 patients and in none of 83 controls (P=0.43). Chlamydia subspecies DNA was found in samples of eight cases and in one control (P=0.01), however, no significant differences were found between the subgroups aortic dissection (P=0.09), TAA (P=0.99) and AAA (P=0.15) and respective controls. CONCLUSIONS: C. pneumoniae does not play a clinically relevant role in acute and chronic aortic disease. The impact of other organisms of the family Chlamydiaceae needs further evaluation.

Aged↗

Increase of chlamydial LPS antibodies in patients with acute coronary syndrome without detection of chlamydial DNA in atherectomy samples.

BACKGROUND: Chlamydia pneumoniae, a respiratory pathogen, has been connected with the pathogenesis of coronary artery disease (CAD). Previous studies indicated a correlation between antibodies to chlamydial LPS and the risk of cardiovascular disease. The aim of this study was to determine whether C. pneumoniae plays a direct role in the pathology of acute coronary syndromes (ACS). METHODS AND RESULTS: Twenty-five consecutive patients (median age 56 years) with ACS (17 acute myocardial infarction, 8 unstable angina) were included in the study and underwent directional coronary atherectomy. Tissue and blood samples were subjected to conventional and real time polymerase chain reaction (PCR) for C. pneumoniae. Antichlamydial immunoglobulin A (IgA) and IgG were examined by LPS enzyme immunoassay (EIA) and microimmunofluorescence (MIF) at intervention and on days 20, 45 and 180 thereafter. DNA of C. pneumoniae was detected neither in atherectomy samples nor in peripheral blood. Serologic results with LPS EIA showed a rapid and significant increase in specific IgA and IgG within 20 days including seroconversion in six cases (4 IgA, 2 IgG). Positive IgA and IgG MIF levels (30% and 87%) remained stable throughout the observation period. CONCLUSIONS: We conclude that negative detection of chlamydial DNA excludes a direct role of chlamydia in ACS. Our findings of rapid LPS antibody increase suggest a role of chlamydial LPS antigen which appears to be released during the acute event e.g. from damaged tissue, indicating a renewed accessibility to the immune system. An indirect role of chlamydia in the further aetiologic process of CAD seems possible.

Acute Disease↗

Importance of surveillance of tularemia natural foci in the known endemic area of Central Europe, 1991-1997.

INTRODUCTION AND PURPOSE: Marked activation of natural foci of tularemia in the known endemic area of Central Europe, comprising the borderland of Slovakia, Austria and the Czech Republic, led to an epidemic outbreak in western Slovakia and an increase in the number of human tularemia cases in the adjoining regions of northeastern Austria and southern Moravia from 1995 to 1997. The aim of this paper was to present the results of a longitudinal study on the prevalence of infection with Francisella tularensis in small mammals and ticks in six localities of western Slovakia and northeastern Austria from 1991 to 1997, and to draw attention to the importance of systematic surveillance of natural foci for epidemiologic prognoses and for taking preventive measures. METHODS: In Slovakia, three localities of the Záhorie lowland were monitored for 3 to 6 years (1991 to 1996) for the presence of F. tularensis in small terrestrial mammals. In Austria, small mammals and ticks from three localities were investigated for 1 to 3 years (1994 to 1997). Spleens of live-trapped animals (at 1- to 2-month intervals) and ticks collected by flagging (in 6- to 8-week intervals) were examined by inoculation of pools into white mice, or individually by cultivation. RESULTS: In four localities under investigation (three localities in western Slovakia and one in Austria), a nearly simultaneous flare-up of tularemia epizootics was recorded in the autumn of 1994. The highest mean prevalence of infection in small mammals was 3.9% in the last quarter of the year, which along with isolations of F. tularensis from Dermacentor reticulatus ticks collected from vegetation in the locality of Austria (1.3% positivity), indicated the high epizootic activity of foci. F. tularensis was isolated from five rodent species--Apodemus flavicollis, A. sylvaticus, Clethrionomys glareolus, Microtus arvalis and Sorex araneus. From 1995 to 1996, the persistent activity of the focus was repeatedly confirmed by isolations of F. tularensis from D. reticulatus ticks. In 1995 a natural focus of tularemia was detected in a further locality of Austria, where the agent was isolated from D. reticulatus. The increased epizootic activity of foci in the endemic region of Central Europe indicated a higher risk of acquiring tularemia for humans and was, in fact, followed by an epidemic outbreak in western Slovakia as well as by a large number of cases in Austria and the Czech Republic. CONCLUSION: Our findings clearly demonstrate that long-term surveillance of natural foci in endemic regions provides useful information on the activation of tularemia foci before the onset of epidemic outbreaks, thus permitting timely epidemiologic prognoses and the institution of preventive measures.

Animals↗

Myocarditis.

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Borrelia burgdorferi Group↗

Possible causes of symptoms in suspected coronary heart disease but normal angiograms.

BACKGROUND: In patients with suspected coronary heart disease and normal angiography, the causes of cardiac symptoms frequently remain undetermined. A correct diagnosis is desirable, however, since some of the underlying disorders may be curable, treatable, influence prognosis, or induce screening of the relatives. HYPOTHESIS: In such patients, the prevalence of arterial hypertension, hemochromatosis, hypothyroidism, hypoparathyroidism, tachycardiomyopathy, amyloidosis, and neuromuscular disorders as a possible cause for their symptoms and the seroprevalence of micro-organisms, known to cause myocardial damage, were assessed. METHODS: Consecutive patients with normal coronary angiograms were invited for two visits comprising clinical history and investigation, electrocardiograms, blood tests, and echocardiography. Patients were investigated neurologically if unexplained anginal chest pain or creatine kinase elevation persisted or if echocardiography showed isolated left ventricular abnormal trabeculations. RESULTS: In 71 patients (31 women, 40 men, mean age 60 years), the most common cause for cardiac symptoms was hypertension (66%), followed by neuromuscular disorders (13%), tachycardiomyopathy (9%), hypothyroidism (4%), and hemochromatosis (3%). The seroprevalence for Chlamydia species was 90%, Helicobacter pylori 70%, Chlamydia pneumoniae 63%, Borrelia burgdorferi sensu lato 15%, and Rickettsia conorii 10%. No possible cause was found in 24% of the patients. CONCLUSIONS: In patients with suspected coronary heart disease and normal angiograms, hypertension, neuromuscular disorders, tachycardiomyopathy, hypothyroidism, and hemochromatosis should be considered as possible causes.

Adult↗

Isolation and polymerase chain reaction typing of Borrelia afzelii from a skin lesion in a seronegative patient with generalized ulcerating bullous lichen sclerosus et atrophicus.

A 64-year-old woman presented with bullous and ulcerating lichen sclerosus et atrophicus (LSA) on the neck, trunk, genital and perigenital area and the extremities. Histology of lesional skin showed the typical manifestations of LSA; in one of the biopsies spirochaetes were detected by silver staining. Despite treatment with four courses of ceftriaxone with or without methylprednisone for up to 20 days, progression of LSA was only stopped for a maximum of 1 year. Spirochaetes were isolated from skin cultures obtained from enlarging LSA lesions. These spirochaetes were identified as Borrelia afzelii by sodium dodecyl sulphate--polyacrylamide gel electrophoresis and polymerase chain reaction (PCR) analyses. However, serology for B. burgdorferi sensu lato was repeatedly negative. After one further 28-day course of ceftriaxone the lesions stopped expanding and sclerosis of the skin was diminished. At this time cultures for spirochaetes and PCR of lesional skin for B. afzelii DNA remained negative. These findings suggest a pathogenetic role for B. afzelii in the development of LSA and a beneficial effect of appropriate antibiotic treatment.

Borrelia↗

Multicenter comparison trial of DNA extraction methods and PCR assays for detection of Chlamydia pneumoniae in endarterectomy specimens.

The reported rate of detection of Chlamydia pneumoniae DNA within atherosclerotic lesions by PCR varies between 0 and 100%. In this study, identical sets of coded experimental atheroma samples (n = 15) and spiked controls (n = 5) were analyzed by 16 test methods in nine centers by means of PCR. The positive controls were correctly identified to levels of 1, 0.1, and 0.01 inclusion bodies of C. pneumoniae/ml of tissue homogenate by 16 (100%), 11 (69%), and 3 (19%) of the test methods, respectively. Three out of 16 negative controls (19%) were rated positive. Positivity rates for atheroma samples varied between 0 and 60% for the different test methods, with the maximum concordant result for positivity being only 25% for one carotid artery sample. There was no consistent pattern of positive results among the various laboratories, and there was no correlation between the detection rates and the sensitivity of the assay used.

Arteriosclerosis↗

A European multicenter study of immunoblotting in serodiagnosis of lyme borreliosis.

A European multicenter study of immunoblotting for the serodiagnosis of Lyme borreliosis showed considerable variation in results obtained from tests with a panel of 227 serum samples. Six laboratories used different immunoblot methods, and a wide range of bands was detected in all the assays. Multivariable logistic regression analysis of data from individual laboratories was used to determine the most discriminatory bands for reliable detection of antibodies to Borrelia burgdorferi sensu lato. These bands were used to construct individual interpretation rules for the immunoblots used in the six laboratories. Further analysis identified a subset of eight bands, which were important in all the laboratories, although with variations in significance. Possible European rules, all closely related, were formulated from these bands, although there was no single rule that gave high levels of sensitivity and specificity for all the laboratories. This is a reflection of the wide range of methodologies used, especially the use of different species and strains of B. burgdorferi sensu lato. The panel of European rules provides a framework for immunoblot interpretation which may be adapted in relation to the characteristics of Lyme borreliosis in local areas.

Antibodies, Bacterial↗

Chronic granulomatous meningitis with multiple cranial nerve lesions hydrocephalus, stroke, sinus thrombosis, and epilepsy.

Most frequently, chronic granulomatous meningitis (CGM) is caused by infectious agents. However, in some cases the cause of CGM remains undetermined. It is unclear whether antimicrobial agents, including antituberculous drugs, are helpful in such cases. We describe a 61-year-old man who had multiple cranial nerve lesions, epilepsy, sinus thrombosis, stroke, and hydrocephalus attributable to CGM. Repeated extensive search for a causative agent in the cerebrospinal fluid (CSF) and the meninges remained negative. Only a single culture of the sputum revealed growth of Mycobacterium tuberculosis, which prompted antituberculous therapy with isoniazid, rifampicin, and ethambutol. After 6 months of therapy, neurologic abnormalities were slightly improved. We conclude that antimicrobial/ antituberculous agents have only a minor short-term effect in long-lasting CGM of undetermined cause.

Aged↗

Erythema migrans and serodiagnosis by enzyme immunoassay and immunoblot with three borrelia species.

There is wide divergence of opinion between physicians regarding the use of serological measures for the diagnosis and treatment of erythema migrans, the hallmark of Lyme borreliosis. We studied the outcome of an enzyme immunoassay and immunoblot (Western blot) used on the sera of patients who had suffered tick bite and erythema migrans, and had been subsequently treated with various antibiotics. Ninety-nine consecutive patients presenting with erythema migrans after tick bite were prospectively recruited at the outpatient department of two Vienna City hospitals and at the consultation office for Lyme borreliosis of the Institute of Hygiene. University Vienna. Blood samples were taken before antibiotic treatment and 3 and 6 months thereafter. Blood samples from 100 blood donors served as controls. Antibodies against Borrelia burgdorferi sensu lato were determined by enzyme immunoassay (IgG and IgM EIA) and by IgG immunoblot. The latter was performed with isolates of B. alzelii (H2) B. burgdorferi sensu stricto (Le) and B. garinii (W) from Austrian patients. The 4 interpretation criteria for immunoblot results were: A (3 bands out of 8), B (2 bands out of 9), C and D (1 band out of 6). In all patients, the erythema resolved within the treatment period. No complications secondary to the borrelia infection were registered. After treatment there was no significant change in titre, nor was there a difference in the immunoblot pattern between the first, second and third serum samples. Serum antibodies to B. burgdorferi were positive by EIA in 22.9% (IgG) and 2.5% (IgM). Immunoblot results offered by borrelia species and by the interpretation criteria, ranging between 8.3% (criterion A, strain Le) and 44.2% (criterion D, strain H2). By EIA, control samples were IgG and IgM positive in 5% and 1%, respectively. Positive immunoblot results with strain H2 were found in 9%, 13%, 18%, and 20% by the criteria A through D respectively. After antibiotic treatment of erythema migrans the immunological response appears to be abrogated. Thus, serological results are not supportive for the diagnosis of erythema migrans, not will they retrospectively prove successful antibiotic treatment of borrelia infection.

Adolescent↗

Chemoprophylaxis for Lyme borreliosis?

Chemoprophylaxis is a term which describes treatment with an antimicrobial chemotherapeutic before, during or shortly after an actual or suspected exposure to an infectious agent in order to prevent clinical disease, which may be severe or even fatal. Lyme borreliosis is considered the most frequent ixodid-tick-transmitted human bacterial infection in the northern hemisphere. For several years there has been a debate on the prophylactic application of antimicrobial chemotherapeutics after an attached Ixodes tick was removed. Would this measure prevent a subsequent borrelia infection and would it be practical? People are exposed to tick-bites mostly during leisure spent in recreational areas which are often tick infested. The proportion of I. ricinus ticks infected with B. burgdorferi s. l. varies from area to area and in a given area also from year to year (infection rate up to a maximum of 55%). The transmission rate strongly depends on the duration of feeding, but it could be shown that the critical time of feeding is much shorter for European I. ricinus than for the North American I. scapularis or I. pacificus ticks. Nevertheless, even the low risk of complications despite the very good chance of treating erythema migrans successfully seems to justify prophylactic treatment for some investigators whilst others do not see an argument for this. Double blinded studies in the USA showed a relatively low frequency of illness after vector tick-bite and absence of disseminated disease manifestations. The efficacy of prophylactic antibiotic treatment after tick-bites is not established. Suggestions to examine removed ticks for borrelia in order to obtain indication for prophylactic antibiotic treatment will fail in practice because of high costs and uncertainty in verifying the transmission. Do we need blinded studies in central Europe on a representative number of cases, although it is known that Lyme borreliosis can be treated effectively even in its second and third stage and has never caused a fatal outcome? We conclude that only a reliable diagnosis of symptoms is the basis for a rational antibiotic treatment, and that instead of chemoprophylaxis for Lyme borreliosis after a vector tick-bite the wait and watch policy is recommended.

Animals↗

Isolation of Borrelia afzelii from circumscribed scleroderma.

A 45-year-old man presented with circumscribed scleroderma (CS) on the extremities. Histology of lesional skin showed the typical manifestations of scleroderma including a perivascular and interstitial infiltrate of lymphocytes and plasma cells; in one of the biopsies spirochaetes could be detected. Despite treatment with penicillin, progression of CS was observed and spirochaetes were isolated from skin cultures obtained from active scleroderma lesions. These spirochaetes were identified as Borrelia afzelii by sodium dodecyl sulphate-polyacrylamide gel electrophoresis of outer surface proteins and polymerase chain reaction (PCR) analysis of their chromosome. After two courses with ceftriaxone the lesions stopped expanding and sclerosis of the skin was diminished. At this time cultures for spirochaetes and PCR of lesional skin for Borrelia afzelii DNA remained negative. The pathogenetic role of Borrelia afzelii in the development of CS is discussed.

Antibodies, Bacterial↗

Differential expression of tumor necrosis factor receptor subtypes on leukocytes in systemic inflammatory response syndrome.

OBJECTIVE: To determine the expression of tumor necrosis factor (TNF) receptor in patients with systemic inflammatory response syndrome (SIRS). DESIGN: Prospective study. SETTING: Intensive care unit and central laboratory. PATIENTS: Blood specimens from 18 healthy volunteers (controls) and 16 patients with SIRS. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Using monoclonal antibodies, fluorescence labeling, and high sensitivity flow cytometry, we measured the expression of membrane TNF receptor subtypes TNF-R55 and TNF-R75 on peripheral blood leukocytes. Receptor expression is expressed as mean fluorescence intensity +/- SD (units: detection channel number). In controls, TNF-R55 was only weakly expressed (monocytes: 2.5+/-1.8; neutrophils: 0.7+/-0.8), whereas expression of TNF-R75 was higher (monocytes: 28.6+/-9.0; neutrophils: 4.8+/-1.0) and was also found on lymphocytes (on CD8+ lymphocytes: 5.7+/-1.8; CD16+: 5.5+/-1.2; CD4+: 9.7+/-3.7). In SIRS, we observed increased expression of TNF-R55 on monocytes (6.9+/-3.4, p<.001) and neutrophils (2.2+/-1.9, p<.01), as well as decreased expression of TNF-R75 on monocytes (17.3+/-13.2; p<.001). The extent of TNF-R55 up-regulation did not correlate with that of TNF-R75 down-regulation. TNF-R55 on monocytes and neutrophils strongly correlated with body temperature but not with survival, whereas monocyte TNF-R75 was considerably lower in nonsurvivors, albeit not significantly (12.3+/-7.1 vs. 23.9+/-16.7; p = .07). CONCLUSIONS: These data indicate that leukocyte TNF-R55 and TNF-R75 react differentially and probably serve different functions in SIRS, which prompts the investigation of receptor subtype-specific therapeutic approaches.

Adult↗

Identification of Borrelia burgdorferi sensu lato species in Europe.

Characterisation at the species level of 142 Borrelia isolates obtained from ticks, humans and rodents in Western Europe was carried out and their geographical distribution was described. Borrelia garinii was the predominant species representing 44% of the isolates and B. afzelii and B. burgdorferi sensu stricto constituted 27% and 19% of isolates respectively. B. valaisiana, (formerly group VS116) constituted 10.5% of isolates. Some differences in the Borrelia species distribution were observed from one country to another, possibly linked to different sources of samples. In the human samples, which were mostly collected in Austria, B. afzelii was preferentially isolated from skin and B. garinii from CSF. B. afzelii was consistently isolated from rodents captured in Switzerland, but one isolate of B. garinii was obtained from a rodent in Austria. B. garinii was by far the most abundant species isolated from Ixodes ricinus ticks in all studied countries. B. valaisiana was isolated from I. ricinus ticks collected from vegetation and from I. ricinus engorged on birds.

Animals↗