Anomalies of a nonequilibrium spinor polariton condensate in a magnetic field.

We observe a strong variation of the Zeeman splitting of exciton polaritons in microcavities when switching between the linear regime, the polariton lasing, and photon lasing regimes. In the polariton lasing regime the sign of Zeeman splitting changes compared to the linear regime, while in the photon lasing regime the splitting vanishes. We additionally observe an increase of the diamagnetic shift in the polariton lasing regime. These effects are explained in terms of the nonequilibrium "spin Meissner effect."

Kaempferol-3,4'-di-O-beta-glucopyranoside-7-O-alpha-rhamnopyranoside as a new flavonoid from Iberis amara L.

A new flavonol glycoside, kaempferol-3,4'-di-O-beta-glucopyranoside-7-O-alpha-rhamno-pyranoside, was isolated from the ethanolic extract of the whole fresh plant of Iberis amara L., an European plant used in gastrointestinal medicine. The structure was established by a combination of 1D and 2D NMR techniques (COSY, HSQC, HMBC, NOESY) as well as UV, IR and mass spectral data.

Outbreak of acute gastroenteritis in an Austrian boarding school, September 2006.

An outbreak of acute gastroenteritis occurred in September 2006 in a boarding school in eastern Austria. Of 113 cases, 101 were hospitalised. In order to identify the outbreak source, a retrospective cohort study on the group at risk was performed, including 222 pupils and 30 staff members. Food exposure in the canteen of the school was identified as the most relevant common link among the cases in the case series investigation. Although the preliminary microbiological investigation made Norovirus infections possible, an in-depth descriptive epidemiological investigation later pointed to food intoxication rather than a viral infection as the cause of the outbreak. The analytical epidemiological investigation implicated boiled rice and chicken wings served in the canteen as the most likely source of the outbreak. Staphylococcus aureus was identified as the causative agent. Further molecular characterisation revealed that the predominant S. aureus type in this outbreak was a new spa type, t2046. The same spa type was isolated from stool specimens of the majority of the cases investigated, from samples of the incriminated boiled rice, and also from a swab of a palmar skin lesion of one of the healthy kitchen workers, who is therefore the most likely source of contamination. This outbreak underlines again the importance of compliance with the basic guidelines for kitchen hygiene.

Occurrence of Salmonella Enteritidis phage type 29 in Austria: an opportunity to assess the relevance of chicken meat as source of human Salmonella infections.

Assuming that the various phage types of Salmonella Enteritidis (S. Enteritidis) are largely equally virulent, the importance of certain foods as sources of infection for human salmonellosis can be deduced from differences in the distribution of phage types in human and non-human samples. In 2002, S. Enteritidis phage type 29 (PT29) was first isolated from non-human test samples in Austria. S. Enteritidis PT29 accounted for 44 (27.7%) of 159 S. Enteritidis strains, derived from veterinary samples of chicken (e.g. meat, giblets) or chicken habitations (e.g. swabs from the coop and excrement). At the food retail level (chicken meat, chicken liver), five (13.1%) of 38 S. Enteritidis isolates were PT29. The proportion of S. Enteritidis PT29 in human samples was much lower. Only 0.4% (30 human primary isolates) of all S. Enteritidis isolates in the year 2002, and 0.33% (23 human primary isolates) of all human S. Enteritidis strains in 2003 were PT29. In our opinion, the discrepancy between the high prevalence of S. Enteritidis PT29 in broilers and chicken meat and the low number of PT29 cases in humans indicates that chicken meat of Austrian origin is currently only a minor source of human S. Enteritidis infections.

Occurrence of Salmonella Enteritidis phage type 29 in Austria : an opportunity to assess the relevance of chicken meat as source of human salmonella infections.

Assuming that the various phage types of Salmonella Enteritidis (S. Enteritidis) are largely equally virulent, the importance of certain foods as sources of infection for human salmonellosis can be deduced from differences in the distribution of phage types in human and non-human samples. In 2002, S. Enteritidis phage type 29 (PT29) was first isolated from non-human test samples in Austria. S. Enteritidis PT29 accounted for 44 (27.7%) of 159 S. Enteritidis strains, derived from veterinary samples of chicken (e.g. meat, giblets) or chicken habitations (e.g. swabs from the coop and excrement). At the food retail level (chicken meat, chicken liver), five (13.1%) of 38 S. Enteritidis isolates were PT29. The proportion of S. Enteritidis PT29 in human samples was much lower. Only 0.4% (30 human primary isolates) of all S. Enteritidis isolates in the year 2002, and 0.33% (23 human primary isolates) of all human S. Enteritidis strains in 2003 were PT29. In our opinion, the discrepancy between the high prevalence of S. Enteritidis PT29 in broilers and chicken meat and the low number of PT29 cases in humans indicates that chicken meat of Austrian origin is currently only a minor source of human S. Enteritidis infections.

Foodborne gastroenteritis outbreak in an Austrian healthcare facility caused by asymptomatic, norovirus-excreting kitchen staff.

An outbreak of norovirus GGII.4 2006b affected an Austrian 600-bed healthcare facility from 15 to 27 March 2009. A total of 204 patients, residents and staff fitted the outbreak case definition; 17 (8.3%) were laboratory-confirmed. Foodborne origin was suspected in the 114 patient and resident cases with onset 15-18 March. A case-cohort study was performed to test the hypothesis that consumption of dishes offered on 14, 15 and 16 March (risk days) was associated with increased risk of infection. Data on food exposure of 62% (317/510) of the patient and resident cohort were available for a simultaneous retrospective cohort study. The case-cohort analysis revealed that consumption of sliced cold sausage offered on 15 March [odds ratio (OR): 3.98; 95% confidence interval (CI): 1.18-14.1], a meat dish with salad (adjusted OR: 2.2; 95% CI: 1.19-4.08) and a rolled spinach pancake (adjusted OR: 2.17; 95% CI: 1.27-3.71) on 16 March were independent risk factors. It is likely that one of the five asymptomatic excretors among the kitchen staff on duty on the risk days was the source of food contamination. The case-cohort study design was found to be a valid alternative to the retrospective cohort study design for the investigation of a suspected foodborne outbreak in a large cohort.

A foodborne norovirus outbreak due to manually prepared salad, Austria 2006.

BACKGROUND: Norovirus is increasingly being recognized as a leading cause of foodborne disease. Nevertheless, well documented foodborne outbreaks due to norovirus are rarely found in the literature. MATERIAL AND METHODS: A retrospective cohort study was conducted for identifying the source of a gastroenteritis outbreak. A total of 325 persons were identified as the at risk group. RESULTS: The overall attack rate was 56% (182/325). Of the four working days of possible foodborne exposure to norovirus (Monday till Thursday), Wednesday (risk ratio [RR]: 18.82; 95%CI 11.82-29.96) and Thursday (RR 2.14; 95%CI 1.65-2.79) turned out to be the most likely days on which infections with norovirus occurred. The day-by-day food specific cohort analyses yielded consumption of salad on Wednesday (adjusted RR 2.82; 95%CI 1.0-7.94) to be associated with highest risk of illness. The most likely source of food contamination is a kitchen assistant having prepared salad manually. She fell ill with symptoms of gastroenteritis on Wednesday during the early working hours and continued working. Human stool samples obtained from five out of six outbreak cases, including the sick kitchen assistant, were RT-PCR positive for norovirus genotype GGII.7 (Leeds-like). CONCLUSION: This foodborne norovirus outbreak underlines the drastic consequences of neglecting the rules of basic kitchen hygiene. Food handlers working despite manifest diarrhea or vomiting--often in fear of job loss--are a common cause of foodborne norovirus outbreaks.

Relationship of pulsed-field profiles with key phage types of Salmonella enterica serotype Enteritidis in Europe: results of an international multi-centre study.

Salmonella is one of the most common causes of foodborne infection in Europe with Salmonella enterica serovar Enteritidis (S. Enteritidis) being the most commonly identified serovar. The predominant phage type for S. Enteritidis is phage type (PT) 4, although PT 8 has increased in incidence. Within these phage types, pulsed-field gel electrophoresis (PFGE) provides a method of further subdivision. The international project, Salm-gene, was established in 2001 to develop a database of PFGE profiles within nine European countries and to establish criteria for real-time pattern recognition. It uses DNA fingerprints of salmonellas to investigate outbreaks and to evaluate trends and emerging issues of foodborne infection within Europe. The Salm-gene database contains details of about 11 700 S. Enteritidis isolates, demonstrating more than 65 unique PFGE profiles. The clonal nature of S. Enteritidis is evidenced by the high similarity and distribution of PFGE profiles. Over 56% (6603/11 716) of the submitted isolates of several different phage types were profile SENTXB.0001, although this profile is most closely associated with PT 4. The next most common profiles, SENTXB.0002 and SENTXB.0005, were closely associated with PT 8 and PT 21 respectively. Studies to investigate the relationship of profile types with outbreaks and possible vehicles of infection suggest that the incidence of PFGE profile SENTXB.0002, and thus PT 8, in some countries may be due to importation of foods or food production animals from Eastern Europe, where PT 8 is amongst the most frequently identified phage types. Collation of subtyping data, especially in the commonly recognized phage types, is necessary in order to evaluate trends and emerging issues in salmonella infection.

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.

Importance of environmental transmission in cases of EHEC O157 causing hemolytic uremic syndrome.

A local outbreak of Shiga toxin (Stx)-producing enterohemorrhagic Escherichia coli (EHEC) O157:H7 causing severe hemolytic-uremic syndrome (HUS) was found to be caused by environmental transmission. Automated ribotyping and pulsed-field gel electrophoresis revealed that four stx2-positive EHEC isolates obtained from two unrelated children, one mother and one cow were identical. Results of an epidemiological investigation strongly suggest that both children were infected via a meadow strewn with manure containing EHEC-positive feces from the infected cow a few days prior to the onset of illness. The cow belonged to a cattle farm neighboring the meadow. This report highlights the risk of acquiring EHEC O157 through indirect contact with a farm environment.

Some aspects of immunodiagnosis in amebiasis.

Antigen from axenically and with crithidia monoxenically grown amebae are compared in complement fixation test and indirect hemagglutination test. While similar reactivity was observed in indirect hemagglutination monoxenic antigen yielded extremely higher titers in complement fixation tests. Transient latex agglutinations of severely ill malaria tropica patients proved to be spontaneous in nature. It is recommended that extra latex is added to the test kits to provide for a check of positive sera for spontaneous agglutination. Glutaraldehyde treated and sensitized sheep red cells were stored under different conditions and their reactivity assessed over various periods of time. No loss of reactivity was found to occur under either condition after the respective times of observation, the longest of which lasted 12 months.

[Immunodiagnostic results of amoebiasis. The value of counter immunoelectrophoresis in comparison to three other immunotests (author's transl)]. / Immundiagnostische Ergebnisse bei der Amöbiasis. Die Leistung der Gegenstrom-Immunelektrophorese im Vergleich zu drei anderen Immuntests.

63 cases of extraintestinal amoebiasis, 17 cases of intestinal amoebiasis, and 25 selected control persons were examined for serum antibodies to antigen from E. histolytica using the counter-immunoelectrophoresis, the complement fixation test, the indirect haemagglutination test and the latex agglutination test. In addition counter-immunoelectrophoresis was applied to 41 sera from patients with extraintestinal amoebiasis whose other serological results were included in a previous study. Even with the employment of our immunological methods, the test results can be used for diagnostic purposes only when they are in accordance with the clinical picture and the exposure. Complete failures of the immuno-diagnostic tests did not occur in our study. On the other hand, there are persons with no symptoms of amoebiasis who have antibodies in two tests, among them sometimes the counter-immunoelectrophoresis, with levels corresponding to those of intestinal or extra-intestinal amoebiasis.

Immunodiagnosis of human paragonimiasis by an enzyme immunoassay.

An enzyme immunoassay was applied to stepless antibody determination in sera from patients with paragonimiasis africanus, paragonimiasis uterobilateralis, paragonimiasis ecuadoriensis, other helminthic infestation, non parasitic diseases and healthy individuals. Crude extracts from adult P. africanus, P. uterobilateralis, P. ecuadoriensis and P. westermani worms served as antigen. The most distinct cross reactivity occurred with sera containing F. hepatica antibodies. Cross reaction was observed to least extent when P. westermani antigen was utilized. By comparison of results obtained by homologous and heterologous Paragonimus antigen it was demonstrated that even species-specific diagnosis of paragonimiasis may be possible when using this system.

[Immunodiagnostic findings in patients with kala-azar]. / Immundiagnostische Befunde bei Kala-Azar-Patienten.

Using three immunoreactions (complement-fixation reaction; enzyme immune test; indirect immunofluorescence), antibody formation was tested in 66 patients with kala-azar and 74 controls (blood donors; accident patients). Moderately elevated and high antibody levels for each of three reactions were defined to provide diagnostic criteria. Moderately high or high antibody concentrations against Leishmania antigen were found in one of the three immunoreactions in 9 patients, in two of the three in 21, and in all three in 36 (55%). No Leishmania antigen was found in the serum of the controls. Similar results were obtained for 80% of those serum samples which had been sent in over a period of seven months to check for Leishmania antibodies (455 of 566 samples). In 25 of the remaining 111 serum samples moderate or high antigen concentrations were demonstrated, but in 21 of them in only one test. Leishmania antibodies were found to persist for several months after the clinical symptoms had disappeared. In 22 kala-azar patients the IgG concentrations were clearly elevated (greater than 3000 mg/dl), in five the IgM concentrations were elevated (greater than 400 mg/dl), while the IgA concentrations were normal or slightly decreased. The data indicate that kala-azar cases can be diagnosed with three appropriate immunoreactions which measure antibody concentrations.

[Contributions to the immunodiagnosis of echinococcosis (author's transl)]. / Beiträge zur Immundiagnostik der Echinokokkose des Menschen.

Serum samples of 49 patients with echinococcosis, 32 of whom were diagnosed parasitologically (demonstration of protoscolices) and 17 of whom were diagnosed clinically (scintigram, histology), were examined for the presence of antibodies. The control group included sera from 74 patients with liver disease and tumors, 10 sera from blood donors, and 1330 sera for which serological tests for echinococcosis had been requested. The antigens used were two types of hydatid fluid, and aqueous extract from E. multilocularis cyst material, and protoscolices from E. granulosus and E. multilocularis. The results showed that the indirect immunofluorescence test with vital protoscolices was the most specific reaction whereas the indirect hemagglutination test with hydatid fluid and the extract from E. multilocularis was the most sensitive reaction. The latex turned out to be the least specific of the methods used. The sensitivity and specificity of our own results are compared with those of other investigators to emphasize the limitations of the immunodiagnosis of echinococcosis.

[Serum antibodies in cystic and alveolar hydatid disease (author's transl)]. / Serum-Antikörper bei der zystischen und alveolären Echinokokkose.

Serum samples of 107 patients with cystic and 30 with alveolar hydatid disease were tested for antibodies with hydatid fluid and extract from cyst material of E. alveolaris as antigens. Complement-fixation, indirect haemagglutination and an indirect enzyme immune (ELISA) technique were employed. The results indicate an antibody picture which confirms the value of serum-antibodies in the diagnosis of hydatid disease. Diagnostically insufficient antibody formation was present in seven patients with cystic and two with alveolar hydatid disease. The indirect haemagglutination test with alveolaris antigen proved to be the most sensitive reaction for antibody demonstration of both echinococci, while the same antigen in the ELISA technique gave species-specific results in patients with E. alveolaris.

Species-specific immunodiagnosis of human echinococcosis with crude antigens.

Crude soluble antigens were evaluated with indirect haemagglutination and ELISA for their specificity in the immunodiagnosis of alveolar and cystic echinococcosis. Using a combination of heterologous crude antigens, the ELISA method made a correct species-specific diagnosis in 96.3% of the patients. These results are similar to those obtained by immunodiagnosis with purified antigens.

[Serum-antibodies in patients with extra-intestinal amoebiasis (amoebic liver abscess) and healthy persons (author's transl)]. / Serum-Antikörper bei Patienten mit extraintestinaler Amöbiasis (Amöbenleberabszess) und Kontrollpersonen

Tests for serum antibodies against two amoeba antigens were performed on serum samples from 70 patients with amoebic liver abscesses, 204 travellers returning from tropical countries and 136 inhabitants of an endemic region without evidence of amoebiasis. Suspicious or borderline results in the complement-fixation, indirect haemagglutination, latex-agglutination, and double-gel diffusion tests occurred in 73.3%-90.4% of patients with amoebic liver abscess, in the same reactions (except double-gel diffusion test) in 12.1-18.9% of travellers in the trophics, and 16.2%-46.3% of inhabitants of endemic regions. There was evidence for the need of performing several tests: patients with amoebic liver abscesses gave diagnostically useful results the more frequently the more tests were performed on a given serum sample. Negative results in the three tests occurred in only one case of multiple liver abscesses, but the sample had been obtained very early.

[Antibody pattern in patients with different forms of leishmaniasis (author's transl)]. / Das Antikörperbild bei Patienten mit Leishmaniosen.

Using the indirect fluorescent antibody test, leishmanial antibodies could be demonstrated in patients with Leishmaniasis. In 18 of 22 cases of kala-azar the titers ranged between 1:160 and 1:1280. In the complement fixation test the titers in patients with kala-azar varied between greater than 1:4 in one case and less than or equal to 1:512 in twelve of the 22 patients. Complement fixing antibodies could not be detected in five of the nine patients with cutaneous or mucocutaneous leishmaniasis. The indirect haemagglutination test proved to be not suitable for diagnostic purposes because it did not detect antibodies in nine out of 22 cases with kala-azar. The IgG fraction of the serum immunoglobulins was increased in most patients with kala-azar. Sensitivity and specificity of the three immunological methods are discussed with reference to the results in 832 undefined sera submitted for routine diagnosis.