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A total of 325 Listeria monocytogenes isolates from human, food and environmental sources were ribotyped with the Qualicon Automated Riboprinter Microbial Characterization System, using the enzyme EcoR1. The human isolates (n=137) represented all isolates from clinical cases in Norway from 1992 to 2005. The food and environmental isolates (n=188) were collected from different food related sources in Norway in the period 1989-2002. A total of 37 ribotypes were differentiated. Most common ribotypes (i.e., ribotypes represented by >5 isolates) were isolated from human as well as food and environmental sources. The exceptions were ribotypes DUP-1062D and 1058A, which were found only among food and environmental samples (14 and 5 times, respectively), and DUP-1042A, which was identified only among human clinical isolates. DUP-1030A, the most frequent ribotype among the human isolates, as well as ribotypes DUP-1042B, DUP-1042C, DUP-1049B and DUP-1062B were identified from both foods, environmental and human sources. DUP-1039C (n=54) and DUP-1045B (n=27) were frequently isolated from patients, food and environmental samples. The isolates were classified into lineages based on ribotyping results. The lineage I strain DUP-1038B was isolated every year from 1992 to 2005 from the human clinical samples. Out of 137 listeriosis cases, 76 (55.6%) were caused by lineage II strains. We found a considerable overlap between ribotypes, lineages and isolation sources. It does not seem possible to establish food strain specific regulations for L. monocytogenes based on ribotyping. [ABSTRACT FROM AUTHOR]

Five salmon processing plants were investigated for periods of eight (plants A and B) and four (plants C, D and E) months for the occurrence of Listeria monocytogenes. A total of 226 strains of L. monocytogenes were isolated and subtyped. Automated ribotyping with DuPont Qualicon RiboPrinter® system with the enzyme EcoR1 was used to differentiate and characterize isolates for simple molecular tracking. The isolated strains could be divided into 16 DuPont ribotypes. The ribotypes DUP-1023C, DUP-1039C, DUP-1044E, DUP-1045B, DUP-1046A, DUP-1062B and 1062C were found to be persistent in the plants, as they were found through the whole sampling period. The remaining 9 ribotypes were isolated sporadically. Five of the persistent subtypes (DUP-1023C, DUP-1039C, DUP-1046A, DUP-1062B and 1062C) where isolated in high numbers. Ribotype DUP-1045B and DUP-1039C were found in four of the five investigated plants. [ABSTRACT FROM AUTHOR]

The purpose of this study was to use automated ribotyping procedure to track Listeria monocytogenes transmission in the cold smoked fish production chain and to characterize L. monocytogenes subtypes associated with the salmon processing industry. A total of 104 isolates, which had previously been obtained from a raw fish slaughter and processing plant (plant B) and an adjacent, downstream, salmon smoking operation (plant A), were characterized. These isolates had been obtained through a longitudinal study on Listeria presence, which covered a 31-week period, in both plants. Isolates had been obtained from samples taken from different machinery used throughout the production process. In addition, six isolates obtained from products produced in plant A two years after the initial study were included, so that a total of 110 isolates were characterized. Automated ribotyping was performed using both the restriction enzymes EcoRI and PvuII to increase the discriminatory power. The 110 L. monocytogenes isolates could be divided into 11 EcoRI ribotypes; PvuII ribotype data yielded multiple subtypes within 7 EcoRI ribotypes for a total of 21 subtypes based on both EcoRI and PvuII ribotyping. A total of three EcoRI ribotypes (DUP-1023C, DUP-1045B, and DUP-1053E) were isolated at multiple sampling times from both plants. In addition, one subtype (DUP-1053B) was isolated at multiple sampling times in only plant A, the salmon smoking operation. These data not only support that L. monocytogenes can persist throughout the salmon production system, but also showed that L. monocytogenes may be transmitted between slaughter and smoking operations or may be unique to smoking operations. While the majority of subtypes isolated have been rarely or never linked to human listeriosis cases, some subtypes have previously caused human listeriosis outbreaks and cases. Molecular subtyping thus is critical to identify L. monocytogenes transmission and niches in order to allow design and implementation of control strategies at the appropriate stage of production and in order to reduce the prevalence of L. monocytogenes linked to human disease. [ABSTRACT FROM AUTHOR]

Two plants processing salmon fillets and cold smoked salmon were investigated for occurrence of Listeria in products and the environment. Analyses were conducted for a period of 31 weeks. At plant A, 252 samples were examined of which 97 were from unprocessed fish and 155 from cold-smoked fish. At plant B, 189 samples of unprocessed fish were investigated. The first examination of unprocessed fish at plant A showed a presence of L. monocytogenes and L. spp. in 81% and 19% of the samples respectively. For cold-smoked fish the figures were 43% and 23%. At plant B, L. monocytogenes was isolated in 63% of the samples. During the test period, management at the processing plant initiated various hygiene precautions to improve the sanitary situation. The last batch of analyses of unprocessed fish at plant A showed a presence of L. monocytogenes and L. spp. in 42% and. 33% of the samples respectively. For cold-smoked fish, the figures were 6% and 11%. The isolation figures at plant B for L. monocytogenes and L. spp. were 50% and 17% respectively. The hygienic precautions did not have a significant effect on the presence of L. monocytogenes and L. spp. We suggest that Listeria bacteria are a part of the resident flora and are not eliminated by current cleaning and sanitation programmes. Cold-smoking, however, gave a significant reduction in the isolation of L. monocytogenes (P?=?0.0082), while the isolation of L. spp. did not decrease after this process. [ABSTRACT FROM AUTHOR]

Hydrologi er læren om vannets (ferskvannets) sirkulasjon, forekomst og bevegelse, og de årsaker som ligger til grunn herfor. For å kunne nyttiggjøre seg og ha kontroll over de muligheter og krefter som vannet er i besittelse av, og for å kunne møte alle de problemer som oppstår i forbindelse med vannets utnyttelse til de forskjellige formål, må man søke å utforske og forstå de forutsetninger og lover som ligger til grunn for alle fenomener i forbindelse med vannets forekomst både over, på og under jordens overflate, slik at nyttevirkningen for samfunnet blir den størst mulige. Som det vil forståes er Hydrologien en geofysisk vitenskap, og som sådan nær beslektet med Meteorologien, idet den behandler forholdet mellom nedbør og avløp og de forandringer i avløpet som forårsakes av variasjoner i temperatur, fordunstning og i de atmosfæriske forhold i sin alminnelighet. Det er også en vekselvirkning tilstede mellom de hydrologiske forhold på den ene side og de geografiske og geologiske på den annen, idet det rennende vann som bekjent øver innflytelse på. jordskorpens utformning i og med sin eroderende, oppløsende og transporterende evne. [ABSTRACT FROM PUBLISHER]

Bifurkasjon, egentlig todeling eller gaffeldeling, vil si at et vassdrag deler sig i to grener som går til hver sin kant uten senere å løpe sammen igjen. Bifurkasjon forekommer hyppig i smavassdrag, fjellbekker f. eks., men er en forholdsvis sjelden foreteelse i større elver. Den mest kjente bifurkasjon-optrer i den sydamerikanske flod Orinoco som ca. 500 km fra sitt utspring sender 1/3 av sin vannmengde over i Amazonflodens vannsystem. Her i Norge har man et velkjent eksempel på bifurkasjon i Lesjaskogsvannet som har avløp både nordover til Romsdalen og sydover til Gudbrandsdalen. Om denne bifurkasjon har naturlige årsaker eller skyldes kunstige inngrep er vel for øvrig et åpent spørsmål. At også Glomma kan fremvise et eksempel på bifurkasjon er kanskje mindre kjent, men ikke desto mindre tilfelle. Under flom vil nemlig en del av elvens vann gjennem Vingersjøen renne over til Vrangselven som har avløp til Sverige. [ABSTRACT FROM PUBLISHER]

A total of 49 isolates of Campylobacter lari from human, poultry, ducks, pigs, and water were genetically characterized. The species were identified by biotyping and multiplex polymerase chain reaction (PCR). Automatic riboprints were performed with the PstI restriction enzyme and RiboPrinter. The identification of the isolates was predicted when the corresponding pattern matched one of the patterns of the DuPont identification (DUP-ID) library and was then assigned an identification number. Thirty-five (71.4%) of the isolates were given a DUP-ID number. The isolates from water and animals showed a high degree of similarity to the human strains represented by DUP-PST1-1010, DUP-PST1-1166, DUP-PST1-1178, and DUP-PST1-1081. Some profiles (i.e., DUP-PST1-2021 and DUP-PST1-1184) were found only among the human isolates. Dendrogram analysis using BioNumerics grouped isolates into three main clusters. One of those clusters contained DUP-PST1-2021, DUP-PST1-1184, and DUP-PST1-1081, which was found in both humans and ducks. A second cluster generated DUP-PST1-1010, found in both humans and poultry, and DUP-PST1-1079, found in water. The third cluster consisted of two strains, DUP-PST1-1066 and DUP-PST1-1078, originating in humans, animals, and water. Three human strains and two poultry strains were diverse and formed their own clusters and could not be assigned a DUP-ID number. Because of the similarity of C. lari isolated from humans, poultry, ducks, pigs, and water, as well as the limited knowledge of environmental survival and its virulence factors, special hygienic precautions should be taken to avoid the risk of transmitting Campylobacter.

The purpose of this study was to use automated ribotyping procedure to track Listeria monocytogenes transmission in the cold smoked fish production chain and to characterize L. monocytogenes subtypes associated with the salmon processing industry. A total of 104 isolates, which had previously been obtained from a raw fish slaughter and processing plant (plant B) and an adjacent, downstream, salmon smoking operation (plant A), were characterized. These isolates had been obtained through a longitudinal study on Listeria presence, which covered a 31-week period, in both plants. Isolates had been obtained from samples taken from different machinery used throughout the production process. In addition, six isolates obtained from products produced in plant A two years after the initial study were included, so that a total of 110 isolates were characterized. Automated ribotyping was performed using both the restriction enzymes EcoRI and PvuII to increase the discriminatory power. The 110 L. monocytogenes isolates could be divided into 11 EcoRI ribotypes; PvuII ribotype data yielded multiple subtypes within 7 EcoRI ribotypes for a total of 21 subtypes based on both EcoRI and PvuII ribotyping. A total of three EcoRI ribotypes (DUP-1023C, DUP-1045B, and DUP-1053E) were isolated at multiple sampling times from both plants. In addition, one subtype (DUP-1053B) was isolated at multiple sampling times in only plant A, the salmon smoking operation. These data not only support that L. monocytogenes can persist throughout the salmon production system, but also showed that L. monocytogenes may be transmitted between slaughter and smoking operations or may be unique to smoking operations. While the majority of subtypes isolated have been rarely or never linked to human listeriosis cases, some subtypes have previously caused human listeriosis outbreaks and cases. Molecular subtyping thus is critical to identify L. monocytogenes transmission and niches in order to allow design and implementation of control strategies at the appropriate stage of production and in order to reduce the prevalence of L. monocytogenes linked to human disease.

Two plants processing salmon fillets and cold smoked salmon were investigated for occurrence of Listeria in products and the environment. Analyses were conducted for a period of 31 weeks. At plant A, 252 samples were examined of which 97 were from unprocessed fish and 155 from cold-smoked fish. At plant B, 189 samples of unprocessed fish were investigated. The first examination of unprocessed fish at plant A showed a presence of L. monocytogenes and L. spp. in 81% and 19% of the samples respectively. For cold-smoked fish the figures were 43% and 23%. At plant B, L. monocytogenes was isolated in 63% of the samples. During the test period, management at the processing plant initiated various hygiene precautions to improve the sanitary situation. The last batch of analyses of unprocessed fish at plant A showed a presence of L. monocytogenes and L. spp. in 42% and. 33% of the samples respectively. For cold-smoked fish, the figures were 6% and 11%. The isolation figures at plant B for L. monocytogenes and L. spp. were 50% and 17% respectively. The hygienic precautions did not have a significant effect on the presence of L. monocytogenes and L. spp. We suggest that Listeria bacteria are a part of the resident flora and are not eliminated by current cleaning and sanitation programmes. Cold-smoking, however, gave a significant reduction in the isolation of L. monocytogenes (P = 0.0082), while the isolation of L. spp. did not decrease after this process.