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R Prager

Publications and source records attributed to R Prager.

At least 19 recordsLinked to original sources
PubMed2006

Distribution of molecular subtypes within Salmonella enterica serotype Enteritidis phage type 4 and S. Typhimurium definitive phage type 104 in nine European countries, 2000-2004: results of an international multi-centre study.

This study investigates the distribution of pulsed-field gel electrophoresis (PFGE) profiles within Salmonella enterica serotype Enteritidis phage type (PT) 4 and S. Typhimurium definitive phage type (DT) 104, from cases of human infection in nine European countries from 2000 to 2004. Isolates were subtyped using standardized methods and gel images submitted by each participating country to the coordinating centre (Health Protection Agency Centre for Infections, London, UK), where they were entered into a central database, developed within BioNumerics software, and designated using an agreed nomenclature. S. Enteritidis PT4 (n=3637) was differentiated into 38 different profiles. Simpson's index of diversity (D) of profiles ranged from 0.2 to 0.4. Profile SENTXB.0001 represented at least 80% of all profiles in each country. S. Typhimurium DT104 (n=1202) was differentiated into 28 different profile types. Simpson's D was at least 0.6 in all countries except in Austria and Italy. In both these countries over 74% of S. Typhimurium DT104 profiles were STYMXB.0013. Profile STYMXB.0061, was predominant in Denmark, Spain, Finland and England and Wales where it represented between 36% and 45% of profiles. Profile STYMXB.0001 represented nearly half of all profiles in Scotland and 23% in England and Wales. PFGE is proving useful for further discrimination within S. Enteritidis PT4 and S. Typhimurium DT104. Ascertainment of international outbreaks involving common serotypes and phage types may be increased by the timely pooling of PFGE profiles within a central database readily accessible to all participating countries.

Bacteriophage Typing↗
PubMed2005

Stroke recurrences in patients with symptomatic vs asymptomatic middle cerebral artery disease.

BACKGROUND: Although the natural history of extracranial carotid artery disease has been investigated systematically, limited data are available on the course of middle cerebral artery (MCA) disease. METHODS: The authors observed 102 consecutive patients (67 men, 35 women; mean age 61.9 years) with significant MCA stenosis or occlusion as demonstrated by transcranial Doppler and transcranial color-coded duplex ultrasonography. Forty-six patients entered the study after TIA (n = 17) or stroke (n = 29); 56 patients were asymptomatic. Neurologic and ultrasound investigations were performed at regular intervals with a mean follow-up of 31 (range 6 to 117) months. Patients were continuously treated with either platelet inhibitors (n = 75) or anticoagulation (n = 27). RESULTS: Nineteen cerebral ischemic events (11 strokes, 8 TIAs) occurred during follow-up, resulting in an overall annual rate of 7.3%. Thirteen events (8 strokes, 5 TIAs) were attributable to the vascular territory ipsilateral to MCA disease. Patients with symptomatic MCA disease at study entry had an overall stroke risk of 12.5% per year (ipsilateral: 9.1%), whereas the annual incidence in primarily asymptomatic MCA disease was only 2.8% (ipsilateral: 1.4%; p < 0.01). Symptomatic MCA disease was an independent predictor for overall (hazard ratio [HR] 7.91, 95% CI 2.03 to 30.79; p < 0.01) and ipsilateral (HR 9.66, 95% CI 1.5 to 62.25; p = 0.02) cerebrovascular events. CONCLUSIONS: Compared with asymptomatic middle cerebral artery disease, there was a high and continuous recurrence rate of ischemic events in symptomatic patients, which was even higher than in patients with symptomatic extracranial carotid artery disease.

Aged↗
PubMed2005

Molecular epidemiology of Salmonella enterica serovar Agona: characterization of a diffuse outbreak caused by aniseed-fennel-caraway infusion.

During 2002-2003 increased numbers of notified salmonellosis due to S. enterica serovar Agona were observed in Germany. In order to understand the recent spread of this serovar and to trace the route of infection to its source, a new phage-typing scheme and pulsed field gel electrophoresis (PFGE) were used to analyse these isolates. By using 14 bacteriophages, 52 phage types were distinguished among the S. Agona strains. PFGE also differentiated 52 different patterns. A combination of both methods generated 94 clonal types among 165 S. Agona strains originating from Germany and other countries including the United States, United Arab Emirates, Turkey, India, Austria and Finland, indicating a great biological diversity within this serovar. However, 36 recent S. Agona isolates from infantile gastroenteritis in Germany, from an untreated batch of aniseed imported from Turkey and from fennel-aniseed-caraway infusion (packed in tea bags) revealed clonal identity indicating their epidemiological relatedness as a new source of infection. It is suggested that strains of S. Agona will continue to be of public health concern, and that phage typing together with PFGE typing should be applied as reliable and rapid tools for epidemiological subtyping and future monitoring.

Apiaceae↗
PubMed2005

[Nation-wide outbreak of Salmonella Give in Germany, 2004].

PURPOSE: In spring and summer 2004, a multistate outbreak of infections caused by Salmonella enterica serovar Give (S. Give), a relatively rare serovar in Germany, was detected. In order to identify a common exposure and to describe the characteristics of infections caused by S. Give, an outbreak investigation was performed. MATERIALS AND METHODS: In addition to passive surveillance through mandatory case-reporting, active case-finding was conducted. A case-control study was undertaken in order to identify the probable vehicle of infection. S. Give strains were isolated and molecular subtyping was performed by pulsed-field gel electrophoresis (PFGE). Rates of hospitalization were assessed in patients with S. Give infection, and compared to the rates found in patients infected by the most common serovar in Germany, S. enteritidis. RESULTS: From March to July 2004, 115 cases of gastroenteritis caused by S. Give were identified, with highest incidences being observed in the states of Lower Saxony and Saxony-Anhalt. Consumption of raw minced pork was strongly associated with S. Give infections (OR: 8.0; 95% CI 2.3-27.7; P = 0.001). This result was confirmed by the detection of common outbreak strains in isolates from both patients and pork, using PFGE. Infections caused by S. Give lead to hospitalization in 55% of patients > or = 60 years, but only in 17 % of younger patients (OR: 6.0; 95% CI 2.1-16.3; P < 0.001) and 33% in patients > or = 60 years with infections caused by S. enteritidis (OR: 2.5; 95% CI 1.1-5.4; P = 0.02). CONCLUSION: This is, to our knowledge, the first documented multistate outbreak of salmonellosis associated with the consumption of raw minced pork in Germany. Since contamination of pork meat with Salmonella cannot be avoided, people with risk factors for severe infection should generally avoid the consumption of raw minced pork. The high hospitalization rates in patients > or = 60 years infected with S. Give possibly indicate a higher virulence of this specific serovar. Even in non-typhoidal salmonellosis, early antibiotic therapy should be considered depending on infecting serovar, age and medical history of the patient.

Age Factors↗
PubMed2005

Improvement of glucose tolerance in type 2 diabetic patients: traditional vs. modern insulin regimens (results from the Austrian Biaspart Study).

OBJECTIVE: Major advantages of modern insulin regimens containing premixed insulin analogues in comparison to traditional insulin regimens have not been evaluated yet. The aim of the present study was to investigate whether meal-related (breakfast, lunch, dinner) application of biphasic insulin aspart 30 (BIAsp 30) provides better glycaemic control than administration of biphasic human insulin 30 (BHI 30) twice per day. RESEARCH DESIGN AND METHODS: In a multi-centre, randomized, open-label parallel trial, a total of 177 patients with type 2 diabetes mellitus were exposed to the two different insulin regimens described above over a study period of 24 weeks. HbA1c and glycemic exposure parameters were measured at predefined intervals. RESULTS: The mean difference between treatment groups in HbA1c after 24 weeks of treatment was 0.08% (p = 0.6419). Analysing the 7-point blood-glucose (BG) profiles, significant differences in BG levels were observed after lunch (156 vs. 176 mg/dl, p = 0.0289), before dinner (142 vs. 166 mg/dl p = 0.006) and after dinner (154 vs. 182 mg/dl p = 0.002) in favour of BIAsp 30 insulin. Prandial BG increment was lower in the BIAsp 30 group at breakfast (p = 0.057) and lunch (p < 0.0005). No difference was found regarding safety parameters in the two treatment groups. CONCLUSIONS: This study demonstrates that meal-related BIAsp 30-insulin maintains postprandial BG control more effectively than traditional BHI 30 insulin twice per day in type 2 diabetic patients.

Adult↗
PubMed2005

Efficacy and safety of insulin glulisine in patients with type 1 diabetes.

Insulin glulisine (glulisine), a human insulin analogue with a rapid-acting time-action profile, has been developed to fulfil the mealtime (bolus) insulin requirement in patients with diabetes. The aim of this multinational, multi-centre, controlled, open-label, randomized, parallel-group study was to compare the efficacy and safety of insulin glulisine (glulisine) to that of insulin lispro (lispro) in adults diagnosed with Type 1 diabetes. Of the 683 patients randomized, 672 received treatment (339 patients received glulisine, 333 patients received lispro). Over the 26-week study, a similar reduction in mean HbA1c occurred in both groups (adjusted mean change from baseline -0.14% in both groups). The basal insulin dose was relatively unchanged from baseline in the glulisine group but increased in the lispro group (glulisine: 0.12 IU vs. lispro: 1.82 IU; p = 0.0001). As a consequence, total daily insulin dose decreased in the glulisine group but increased in the lispro group (glulisine: -0.86 IU vs. lispro: 1.01 IU; p = 0.0123). There was no relevant difference between the two groups in the reporting of symptomatic hypoglycaemia (overall, nocturnal and severe). This study demonstrates that glulisine provides equivalent glycaemic control to lispro. The clinical relevance of any difference in total daily insulin dose remains to be established.

Adult↗
PubMed2005

Pilot study to evaluate microarray hybridization as a tool for Salmonella enterica serovar Typhimurium strain differentiation.

In developed countries, Salmonella enterica subspecies 1 serovars Enteritidis and Typhimurium range among the most common causes of bacterial food-borne infections. The surveillance and typing of epidemic Salmonella strains are important tools in epidemiology. Usually, Salmonella enterica subspecies 1 serovars are differentiated by serotyping for diagnostic purposes. Further differentiation is done by phage typing as well as molecular typing techniques. Here we have designed and evaluated a prototype DNA microarray as a tool for serovar Typhimurium strain differentiation. It harbors 83 serovar Typhimurium probes obtained by differential subtractive hybridization and from the public database. The microarray yielded reproducible hybridization patterns in repeated hybridizations with chromosomal DNA of the same strain and could differentiate five serovar Typhimurium reference strains (DT204, DT104, DT208, DT36, and LT2). Furthermore, the microarray identified two distinct groups among 13 serovar Typhimurium DT104 strains. This correlated with observations from pulsed-field gel electrophoresis analysis. Twenty-three further serovar Typhimurium strains were analyzed to explore future directions for optimization of the simple 83-probe DNA microarray. The data presented here demonstrate that DNA microarrays harboring small numbers of selected probes are promising tools for serovar Typhimurium strain typing.

Bacterial Typing Techniques↗
PubMed2005

An outbreak of Salmonella München in Germany associated with raw pork meat.

In summer 2001, an outbreak of Salmonella München occurred in Germany. We conducted descriptive epidemiology and hypothesis-generating interviews among case patients, two retrospective cohort studies, and a case-control study of suboutbreaks. We performed pulsed-field gel electrophoresis (PFGE) from selected patient isolates and a limited trace-back investigation for analytical purposes. Four states were consecutively affected: Saxonia (SX), Brandenburg (BB), Berlin (BE), and Baden-Württemberg (BW). Although hypothesis-generating interviews failed to identify a plausible food item, descriptive data and investigations of the suboutbreaks suggested pork meat as a probable source in three states (SX, BB, and BE) but not in BW. The PFGE profiles from isolates of case patients in the first three states were indistinguishable but differed from PFGE profiles of case patients in BW. Trace-back investigation suggested that contamination of pork meat occurred early in the rearing-production chain. This outbreak demonstrates how contamination early in the production process that can yield different end products may complicate multistate outbreaks. Investigation of suboutbreaks and use of the trace-back method as investigational tools may be useful adjuncts in solving the problem of multistate outbreaks.

Age Distribution↗
PubMed2004

Shigellosis - a re-emerging sexually transmitted infection: outbreak in men having sex with men in Berlin.

In December 2001, the Robert Koch-Institut (RKI) was informed about a cluster of 10 Shigella sonnei infections in men who have sex with men (MSM), diagnosed in Berlin since September 2001. A retrospective investigation on sexual risk factors for infection in all shigella cases from Berlin from 2001 was initiated by sending a questionnaire to all patients without known travel history. Simultaneously laboratories were asked to send new shigella isolates from patients to the National Reference Centre at the RKI. Out of 29 responders, 24 self-identified as MSM. Seventeen of these reported sexual contacts as the most likely potential risk of infection. Almost all MSM reported direct or indirect oral-anal sexual contacts in the week before they fell ill. Fifteen of 27 shigella isolates collected during the prospective sampling period showed identical plasmid profiles, PFGE- and resistance patterns and can therefore be regarded as clonally identical. Asymptomatic and/or prolonged shedding in the reconvalescent phase may contribute to the transmission risk of shigella infection during oral-anal sexual practices. Awareness among practitioners and among MSM about the risk of sexual transmission of orally transmitted agents needs to be raised.

Adult↗
PubMed2004

Processing and visualizing three-dimensional ultrasound data.

This paper describes techniques for the visualization and processing of three-dimensional (3D) ultrasound data. The nature of such data demands specialized algorithms, which differ from those employed for other medical imaging modalities. In this paper, the emphasis is placed on generic processing techniques, which are relevant across a wide range of 3D ultrasound application domains.

Algorithms↗
PubMed2004

Presence of sopE gene & its phenotypic expression among different serovars of Salmonella isolated from man & animals.

BACKGROUND & OBJECTIVES: Salmonellae cause a spectrum of diseases in man and animals but their virulence factors responsible for induction of gastroenteritis and/or systematic infection are still poorly understood. Also, the different subspecies and serovars of Salmonella differ considerably in their virulence for man and animals. There is increasing evidence that Salmonella possesses a dedicated protein secretion system denoted type III secretion system (TTSS) that is involved in the early stage of Salmonella infection. One such TTSS is Salmonella outer protein E (SopE) that helps in the invasion of Salmonella by stimulating membrane ruffling. In the present study the presence of sopE gene and its phenotypic expression (SopE protein) among different serovars of Salmonella enterica isolated from man and animals in India was investigated. METHODS: A total of 50 isolates of S. enterica belonging to 11 serovars were tested for the presence of sopE gene by polymerase chain reaction. The in vitro phenotypic expression of SopE protein was detected by Western blotting using anti-SopE serum. RESULTS: Of the 50 isolates of S. enterica belonging to 11 serovars tested for the presence of sopE,14 belonging to three serovars viz., Enteritidis, Gallinarum and Virchow were found to carry the sopE gene. Similarly, 13 isolates belonging to same three serovars were found to express SopE protein phenotypically as detected by Western blotting using anti-SopE serum. INTERPRETATION & CONCLUSION: The results indicated that sopE gene appeared to be distributed and conserved among only a few serovars of Salmonella (Enteritidis, Gallinarum and Virchow) irrespective of their source of isolation. The presence of sopE gene in Salmonella provides an important pathogenic means to invade epithelial cells.

Animals↗
PubMed2003

Strong association between shiga toxin-producing Escherichia coli O157 and virulence genes stx2 and eae as possible explanation for predominance of serogroup O157 in patients with haemolytic uraemic syndrome.

The aim of this study was to investigate the association between Shiga toxin-producing Escherichia coli (STEC) O157 and the simultaneous presence of the virulence genes stx2 and eae in STEC from patients with gastroenteritis. In Germany, the proportion of serogroup O157 is substantially higher among STEC isolates from patients with haemolytic uraemic syndrome (HUS) than among STEC isolates from patients with gastroenteritis. The reason for this is unknown. Independent of serogroup, the virulence genes stx2 and eae have been associated with severe disease. Data collected in 2000-2001 from a Germany-wide laboratory-based surveillance system for STEC-associated gastroenteritis in patients <15 years were analysed. Overall, 18% of the STEC isolates belonged to serogroup O157. Compared with non-O157 strains, 0157 isolates were strongly associated with the simultaneous presence of both an stx2 gene and the eae gene (OR, 76; 95%CI, 27-230). Within the subset of STEC isolates that carried both virulence genes, 60% belonged to serogroup O157, a proportion similar to that found in STEC isolates from pediatric patients with HUS in Germany and Austria (67%, P=0.35). These data suggest that the more frequent carriage of both virulence genes, i.e. stx2 and eae, forms the basis of why STEC O157 predominates in patients with HUS.

Adhesins, Bacterial↗
PubMed2003

Acute-phase response and immunological markers in morbid obese patients and patients following adjustable gastric banding.

OBJECTIVE: We measured markers of acute-phase response and immunological markers in morbid obese patients and in formerly morbid obese patients after a massive weight loss following adjustable gastric banding (GB). SUBJECTS: A total of 49 morbid obese female patients with a body mass index (BMI) above 40 kg/m(2) were investigated during a study period of 6 months. Of these, 24 patients received a gastric banding (GB) and lost a minimum of 20 kg in 1 y (GB group) and 25 patients maintained their weight (obese group). In sum, 13 normal weight subjects (BMI<24 kg/m(2)) were taken for controls. METHOD: Plasma concentration of the acute-phase proteins, C-reactive protein (CRP), orosomucoid, complement factors C3 and C4 and white blood cell count, lymphocyte subsets and serum immunoglobulins were analyzed. RESULTS: Acute-phase proteins were significantly lower in GB compared to morbid obese patients and remained significantly elevated in GB compared to controls. In addition, leukocytes, polymorphonuclear leukocytes and lymphocytes were significantly lower after GB and reached levels comparable to controls (except PMN). No difference in CD3 counts was observed in the three groups. CD4 increased and CD8 decreased in obese and GB patients when compared to controls whereas no statistical difference was found between obese and GB patients. CONCLUSION: Our results confirm the positive effect of GB followed by a massive weight loss without apparent malnutrition. Subclinical chronical inflammation in morbid obese patients leads to irregularities in leukocyte and lymphocyte subsets. These alterations can be positively influenced by GB.

Acute-Phase Proteins↗
PubMed2003

Inverse relation between amylin and glucagon secretion in healthy and diabetic human subjects.

BACKGROUND: The role of amylin, which is cosecreted together with insulin by the pancreatic B-cells, in the pathogenesis of type-2 diabetes is still unclear. To elucidate a possible relation between amylin and glucagon we directly evaluated the respective prehepatic secretions following administration of a 75-g oral glucose load (OGL) in humans. MATERIALS AND METHODS: We studied six healthy controls (C), six obese, insulin resistant subjects (O) and six patients with type 2 diabetes (D). Catheters were placed in the femoral artery and hepatic vein according to the hepatic vein catheterization technique. Splanchnic blood flow was assessed by infusion of indocyanine-green dye. The measured variables were analyzed by a general circulatory model for calculation of prehepatic secretion. RESULTS: The total amount of released glucagon was not different between the respective groups (20.5 +/- 2.3 in C, 27.7 +/- 5.1 in O and 27.9 +/- 5.4 micro g/4 h in D). When considered as the difference from the fasting profile, however, glucagon secretion was reduced by 3.5 +/- 14% in C, 25 +/- 12% in O and increased by 36 +/- 21% in D (P = 0.051, D vs. C). Amylin secretion was increased in O (1.10 +/- 0.15) vs. C (0.63 +/- 0.05, P < 0.05) and D (0.24 +/- 0.10 nmol, P < 0.01). Following glucose administration, glucagon secretion significantly inversely correlated with secretion of amylin (r = -0.6, P < 0.01), but not with that of insulin (r =-0.23, P = 0.36). CONCLUSIONS: The inverse correlation between amylin and glucagon secretion suggests that amylin modulates glucagon secretion following oral glucose administration. This study proves for the first time a role of endogenous amylin in the regulation of glucose homeostasis.

Adult↗
PubMed2002

Phage typing and PFGE pattern analysis as tools for epidemiological surveillance of Salmonella enterica serovar Bovismorbificans infections.

Some years ago, an increase in the number of sporadic cases and outbreaks of salmonellosis due to S. enterica serovar Bovismorbificans was observed in several European countries including Finland, Sweden, England/Wales, Austria, and Germany. In order to understand the recent spread of this serovar and to trace the route of infection back to its source, it was considered necessary to subtype S. Bovismorbificans isolates. Using phage typing (newly described here) and molecular fingerprinting (PFGE-pattern, plasmid profiles and ribotype) the isolates of European origin could be subtyped and compared to S. Bovismorbificans isolates that originated in overseas countries such as Australia, Thailand, India, etc. where this serovar was isolated more frequently. Significant clonal diversity was identified but some of the clonal types of S. Bovismorbificans dominated the epidemics and single cases in Europe as well as in overseas countries. The clonal identity among these isolates indicates an international distribution, new sources of infection, and highlights the urgent requirement for standardized laboratory based surveillance networks (e.g. Enter-Net). Moreover, it is suggested that strains of S. Bovismorbificans will continue to be of concern in public health and that phage typing together with PFGE typing can be applied as reliable and rapid tools for their future monitoring.

DNA Fingerprinting↗
PubMed2002

[Reduction of cardiovascular morbidity and mortality by combined antihypertensive drug therapy in patients with type 2 diabetes mellitus].

The coexistence of diabetes mellitus in hypertensive patients doubles the number of cardiovascular events (relative risk: 1.73-2.77) and cardiovascular mortality (relative risk: 2.25-3.66). Therapeutic interventions concentrating on elevated blood glucose alone for prevention of late complications were not effective in essential reduction of cardiovascular morbidity and mortality. For that reason therapies, focussing on other macrovascular risk factors, did increase significantly in the last decade. Strategies for reduction of the macrovascular risk include the aggressive treatment of hypertension. In the now published hypertension intervention studies in diabetic patients many different objectives were studied. As we already know, lowering of blood pressure does reduce cardiovascular risk. The optimal blood pressure threshold is not known yet, but of major interest. To find the most effective antihypertensive agent and the most effective combination therapy for diabetic patients, the most frequently used antihypertensive agents were compared with each other. Very interesting are the special effects of some substances, which exceed the lowering of blood pressure, like effects on the endothelinn or on coagulation disturbances. These protective and antiatherosclerotic effects could possibly get relevance even in normotensive patients. Concerning this special question, ACE-inhibitors and Angiotensin II receptor antagonists are getting more and more in the focus of interest and seem to be superior compared to other substances. Concluding the existing evidence from hypertension studies the following recommendations can be deduced: Diabetic patients with at least one additional cardiovascular risk factor should get an ACE-inhibitor in combination with other antihypertensive agents or as monotherapy. For combination therapy all the available antihypertensive agents are appropriate and can lower blood pressure adequately.

Angiotensin Receptor Antagonists↗
PubMed2002

Occurrence of Salmonella enterica serovar Dublin in Austria.

In Austria, Salmonella enterica subsp. enterica serovar Dublin, a bovine-adapted serovar, rarely causes infections in humans. In 2000, Austria was within the European mean with an incidence of 0.1 per million inhabitants. Our data show that the vast majority of all serovar Dublin infections (human and non-human) can be traced epidemiologically to two districts in the Tyrol. This concentration of cases can be explained by a particularly traditional aspect of cattle farming in this area, the alpine pasture. There is an increased risk of cross infection due to the communal keeping of animals from various farms. Infected cattle are a source of infection for humans, and transmission usually occurs from eating beef and drinking cows milk. Using pulsed field gel electrophoresis and automated ribotyping, three out of five isolates from human infections could be traced to characteristic Tyrolean Dublin clones. Bacteriological screening for faecal carriage before the transfer of cattle from risk-herds to the alpine pastures and before the return from risk-pastures to the farms would be a possible starting point to prevent cross-contamination of large mixed herds and contamination of pasture through latently infected cattle. Appropriate research is necessary.

Animals↗