Detection and identification of Ehrlichia, Borrelia burgdorferi sensu lato, and Bartonella species in Dutch Ixodes ricinus ticks. (17/1110)

A sensitive and specific PCR hybridization assay was developed for the simultaneous detection and identification of Ehrlichia and Borrelia burgdorferi sensu lato. In separate assays the 16S rRNA gene of Ehrlichia species and the 23S-5S rRNA spacer region of B. burgdorferi sensu lato were amplified and labeled by PCR. These PCR products were used in a reverse line blot hybridization assay in which oligonucleotide probes are covalently linked to a membrane in parallel lines. Hybridization of the samples with the oligonucleotide probes on this membrane enabled the simultaneous detection and identification of Ehrlichia, B. burgdorferi, and Bartonella species in 40 different samples. The application of the assay to DNA extracts from 121 Ixodes ricinus ticks collected from roe deer demonstrated that 45% of these ticks carried Ehrlichia DNA. More than half of these positive ticks carried species with 16S rRNA gene sequences closely related to those of E. phagocytophila and the human granulocytic ehrlichiosis agent. The majority of the other positive ticks were infected with a newly identified Ehrlichia-like species. In addition, 13% of the ticks were infected with one or more B. burgdorferi genospecies. In more than 70% of the ticks 16S rRNA gene sequences for Bartonella species or other species closely related to Bartonella were found. In five of the ticks both Ehrlichia and B. burgdorferi species were detected.  (+info)

Ultradian, circadian and seasonal rhythms in cortisol secretion and adrenal responsiveness to ACTH and yarding in unrestrained red deer (Cervus elaphus) stags. (18/1110)

Seasonal changes in the activity and responsiveness of the adrenal gland in red deer (Cervus elaphus) stags were quantified by measuring 24 h endogenous cortisol secretory profiles and plasma cortisol responses to either administration of exogenous ACTH or a standardised stressor during November (period of velvet growth), February (pre-rut), April (mid-rut) and July (post-rut) (southern hemisphere) using a remote blood sampling device (DracPac). Ultradian rhythms in the concentration of plasma cortisol were observed resulting from the episodic secretion of cortisol from the adrenal cortex at a mean rate of 0.8 pulses/h. Circadian rhythms in plasma cortisol concentrations were also found in 11 out of the 20 complete 24 h profiles (mean amplitude, 3.8+/-1.4 ng/ml). Seasonal rhythms in mean 24 h plasma cortisol concentrations and cortisol pulse parameters were also observed. Mean 24 h plasma cortisol concentrations were higher in November (12.5+/-1.0 ng/ml) than in February (6.3+/-1.0 ng/ml), April (4.0+/-1.0 ng/ml) or July (4.2+/-1. 0 ng/ml). Cortisol pulse height, nadir and amplitude were all significantly higher in November than at other times of the year (P<0.01). Peak cortisol concentrations following infusion of ACTH(1-24) (0.04 IU kg(-1)) were higher (P<0.05) in November (55.8+/-2.7 ng/ml) and lower (P<0.001) in April (33.7+/-1.8 ng/ml) than those in February and July (48.7+/-2.0 ng/ml and 45.4+/-2.0 ng/ml respectively). The area under the cortisol response curve was significantly smaller (P<0.05) in April (266.6+/-15.3 ng/ml/190 min) than at other times of the year (February, 366.1+/-15.3 ng/ml/190 min; July, 340.7+/-15.3 ng/ml/190 min and November, 387.8+/-21.2 ng/ml/190 min). These data demonstrate that the adrenal gland of the red deer stag exhibits ultradian, circadian and seasonal rhythms in activity, and that its responsiveness to ACTH varies with season. November, a period of reproductive quiescence in the southern hemisphere, with new antler growth and rapid weight gain, is associated with higher mean plasma cortisol concentrations and a greater responsiveness to exogenous ACTH. In contrast, the breeding season is associated with lower adrenal activity and responsiveness.  (+info)

Bone turnover associated with antler growth in red deer (Cervus elaphus). (19/1110)

Although it is known that skeletal bone depletion occurs during antler growth in deer, it is not clear whether repletion of the skeleton takes place before or after completion of antler development. This study attempted to correlate repeated scanning electron microscopic measures of ilium and rib bone porosity from six approximately 2-monthly biopsy samples (using back-scattered imaging) and biochemical markers of bone turnover (serum hydroxyproline and osteocalcin concentrations) taken for 11 months with antler growth in six red deer stags. No changes were detected in ilium samples but changes in porosity of rib bones and an elevation of the biochemical markers indicated that skeletal depletion occurred during the antler growth period. However, the decrease in rib bone porosity and decline in markers of bone turnover took place before completion of antler growth, indicating that a considerable amount of skeletal repletion could have occurred whilst antlers were also undergoing bone accretion. This latter finding extends the current view of antler growth being accompanied by a form of reversible osteoporosis in the skeleton by showing that there is a period when the antlers and skeleton are both undergoing net bone formation.  (+info)

Typing Listeria monocytogenes by random amplified polymorphic DNA (RAPD) fingerprinting. (20/1110)

Twenty epidemiologically unrelated Listeria monocytogenes strains isolated from different animals, locations and on different dates in Japan were classified into 18 types by the random amplified polymorphic DNA (RAPD) fingerprinting technique with four primers. Further, seven epidemiologically related L. monocytogenes strains isolated from raw milk and a bulk tank on a dairy farm represented the same RAPD type suggesting that they were all of the same origin. Therefore, RAPD-polymerase chain reaction (PCR) analysis, which is rapid, simple and inexpensive to perform, can be used in surveys as a convenient epidemiological technique.  (+info)

A focus of deer tick virus transmission in the northcentral United States. (21/1110)

We screened salivary glands from adult deer ticks collected near Spooner and Hayward, Wisconsin, to determine whether deer tick virus, a recently described flavivirus, occurs with other tickborne agents in the upper Midwest. Intraacinar inclusions suggestive of replicating virus were detected in 4 (4.6%) of 87 ticks. The virus was isolated by suckling-mouse inoculation.  (+info)

What determines the bending strength of compact bone? (22/1110)

The bending strength of a wide variety of bony types is shown to be nearly linearly proportional to Young's modulus of elasticity/100. A somewhat closer and more satisfactory fit is obtained if account is taken of the variation of yield strain with Young's modulus. This finding strongly suggests that bending strength is determined by the yield strain. The yield stress in tension, which might be expected to predict the bending strength, underestimates the true bending strength by approximately 40 %. This may be explained by two phenomena. (1) The post-yield deformation of the bone material allows a greater bending moment to be exerted after the yield point has been reached, thereby increasing the strength as calculated from beam formulae. (2) Loading in bending results in a much smaller proportion of the volume of the specimens being raised to high stresses than is the case in tension, and this reduces the likelihood of a weak part of the specimen being loaded to failure.  (+info)

Study of restriction fragment length polymorphism analysis and spoligotyping for epidemiological investigation of Mycobacterium bovis infection. (23/1110)

Restriction fragment length polymorphism (RFLP) analysis with probes derived from the insertion element IS6110, the direct repeat sequence, and the polymorphic GC-rich sequence (PGRS) and a PCR-based typing method called spacer oligonucleotide typing (spoligotyping) were used to strain type Mycobacterium bovis isolates from the Republic of Ireland. Results were assessed for 452 isolates which were obtained from 233 cattle, 173 badgers, 33 deer, 7 pigs, 5 sheep, and 1 goat. Eighty-five strains were identified by RFLP analysis, and 20 strains were identified by spoligotyping. Twenty percent of the isolates were the most prevalent RFLP type, while 52% of the isolates were the most prevalent spoligotype. Both the prevalent RFLP type and the prevalent spoligotype were identified in isolates from all animal species tested and had a wide geographic distribution. Isolates of some RFLP types and some spoligotypes were clustered in regions consisting of groups of adjoining counties. The PGRS probe gave better differentiation of strains than the IS6110 or DR probes. The majority of isolates from all species carried a single IS6110 copy. In four RFLP types IS6110 polymorphism was associated with deletion of fragments equivalent in size to one or two direct variable repeat sequences. The same range and geographic distribution of strains were found for the majority of isolates from cattle, badgers, and deer. This suggests that transmission of infection between these species is a factor in the epidemiology of M. bovis infection in Ireland.  (+info)

Genetic diversity of pestiviruses: identification of novel groups and implications for classification. (24/1110)

The complete Npro coding sequences were determined for 16 pestiviruses isolated from cattle, pig, and several wild ruminant species including reindeer, bison, deer, and bongo. Phylogenetic analysis enabled the segregation of pestiviruses into the established species bovine viral diarrhea virus-1 (BVDV-1), BVDV-2, border disease virus (BDV), and classical swine fever virus (CSFV). For BVDV-1 five distinct subgroups were identified, while BVDV-2, BDV, and CSFV were each subdivided into two subgroups. The virus isolates from bongo and deer as well as one porcine virus isolate belong to BVDV-1. Interestingly, the isolates from reindeer and bison are distinct from the established pestivirus species. The Npro sequences from these two viruses are more similar to BDV than to the other pestivirus species. Calculation of the pairwise evolutionary distances allowed a clear separation of the categories species, subgroup, and isolate only when the reindeer/bison viruses were considered as members of an additional pestivirus species. Furthermore, the entire E2 coding sequences of a representative set of virus isolates covering all recognized species and subgroups were studied. Segregation of pestiviruses based on the E2 region was identical with that obtained with the N(pro) sequences.  (+info)