Predilection Muscles and Physical Condition of Raccoon Dogs (Nyctereutes procyonoides) Experimentally Infected with Trichinella spiralis and Trichinella nativa

The predilection muscles of Trichinella spiralis and T. nativa were studied in 2 experimental groups of 6 raccoon dogs (Nyctereutes procyonoides), the third group serving as a control for clinical signs. The infection dose for both parasites was 1 larva/g body weight. After 12 weeks, the animals were euthanized and 13 sampling sites were analysed by the digestion method. Larvae were found in all sampled skeleton muscles of the infected animals, but not in the specimens from the heart or intestinal musculature. Both parasite species reproduced equally well in the raccoon dog. The median density of infection in positive tissues was 353 larvae per gram (lpg) with T. spiralis and 343 lpg with T. nativa. All the infected animals had the highest larvae numbers in the carpal flexors (M. flexor carpi ulnaris). Also tongue and eye muscles had high infection levels. There were no significant differences in the predilection sites between these 2 parasite species. Trichinellosis increased the relative amount of fat, but not the body weight in the captive raccoon dogs. Thus, Trichinella as a muscle parasite might have catabolic effect on these animals

Persistence of Trichinella spiralis in Rat Carcasses Experimentally Mixed in Different Feed

Trichinella spiralis infected rat carcasses were incubated for 6 weeks in several animal feeds to assess how long Trichinella can present a risk for an outbreak in contaminated feeds. In groups of 6, 24 infected target rats were placed in silage, grained barley, propionic acid-preserved feed, and also into simulated pasture conditions. Test environments were sampled after one-, 2-, 4-, and 6-week-incubations. Trichinella larvae were recovered by digestion, and their infectivity was evaluated in rats. A two-week incubation reduced the number of recovered larvae, but still after 6 weeks low numbers were isolated from all feeds except from the experimental group simulating pasture conditions. After 2 weeks storage, the larvae were infective in all storage environments. However, up to 4 weeks, they survived only in the propionic acid-fermented feed and there in small numbers with reduced reproductive capability. This indicates the possibility of farm animals to get infection from rats or other infected material being hazardously mixed with hay or other feed. If silage is stored for at least one month before use, however, the risk from this forage appears to be minimized

Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial

© Cuzick et al. Open Access article distributed under the terms of CC BY.http://dx.doi.org/10.1016/S1470-2045(14)71171-

Classification of the nucleolytic ribozymes based upon catalytic mechanism

The nucleolytic ribozymes carry out site-specific RNA cleavage reactions by nucleophilic attack of the 2’-oxygen atom on the adjacent phosphorus with an acceleration of a million-fold or greater. A major part of this arises from concerted general acid-base catalysis. Recent identification of new ribozymes has expanded the group to a total of nine and this provides a new opportunity to identify sub-groupings according to the nature of the general base and acid. These include nucleobases, hydrated metal ions, and 2’-hydroxyl groups. Evolution has selected a number of different combinations of these elements that lead to efficient catalysis. These differences provide a new mechanistic basis for classifying these ribozymes

Evaluation of two PCR-based techniques for molecular epidemiology in Finland, a high-endemic area with four sympatric Trichinella species

Trichinella larvae collected from wildlife, domestic and synanthropic animals in Finland were identified to species by two molecular techniques: Random amplified polymorphic DNA (RAPD) polymerase chain reaction (PCR) and the recently described multiplex PCR. The RAPD-PCR was very sensitive to the sub-optimal preservation muscle larvae and resulting in weak and smeared bands on the gels for such material. However, the same samples yielded easily recognizable bands in the multiplex PCR; this latter technique is then recommended for epidemiological studies, especially when the preservation of the samples is sub-optimal. For larvae in good condition the unequivocal bands obtained by multiplex was the easiest identifiable. Four species of Trichinella were identified in the material: T. spiralis, T. nativa, T. britovi, and T. pseudospiralis. Trichinella britovi is a new record for Finland, and T. pseudospiralis is a new record for Northern Europe. Mixed infections between T. britovi and T. spiralis, T. nativa and T. spiralis, and between T. britovi and T. nativa were detected; this is the first record of a mixed infection between T. spiralis and T. nativa in a naturally infected host. Raccoon dogs were the only host species from which all of the four Trichinella species were detected. Trichinella spiralis was found in both domestic animals and wildlife, but none of the sylvatic Trichinella species were detected in domestic pig