Isolation, purification, and characterization of pregnancy-specific protein B from elk and moose placenta. (25/1110)

Pregnancy-specific protein B (PSPB) was isolated, purified, and partially characterized from elk and moose placenta. The procedure, which was monitored by bovine PSPB (bPSPB) RIA, included homogenization and extraction in aqueous solution, acidic and ammonium sulfate precipitation, and ion exchange, gel filtration, and affinity chromatographies. The estimated molecular sizes of moose PSPB (mPSPB) were 58 kDa and 31 kDa, and of elk PSPB (ePSPB) were 57 kDa, 45 kDa, and 31 kDa by SDS-PAGE. The isoelectric points of mPSPB were 4.8, 6.6, and 6.7, and of ePSPB were 4.8, 4.9, 6.1, and 6.2 as determined by isoelectric focusing and two-dimensional gel electrophoresis. The carbohydrate contents of mPSPB and ePSPB were approximately 3.15% and 4.98%, respectively. Although ePSPB and mPSPB were recognized by anti-bPSPB in an Ouchterlony double immunodiffusion test, they were found to share identical epitopes and partial identities compared to bPSPB. After treatment at different temperatures (20-60 degrees C) for 1 h, the immunoreactivities of ePSPB and mPSPB in serum were very stable. Only ePSPB in serum treated at 60 degrees C lost some immunoreactivity. After alteration of serum pH (pH 3-11) for 2 h, the immunoreactivities of ePSPB and mPSPB became lower at pH 3 and 4, and remained stable from pH 5 to 11. These data show that moose and elk PSPB have properties similar to those of bovine and ovine PSPB.  (+info)

Early determinants of lifetime reproductive success differ between the sexes in red deer. (26/1110)

In polygynous, sexually dimorphic species, sexual selection should be stronger in males than in females. Although this prediction extends to the effects of early development on fitness, few studies have documented early determinants of lifetime reproductive success in a natural mammal population. In this paper, we describe factors affecting the reproductive success of male and female red deer (Cervus elaphus) on the island of Rum, Scotland. Birthweight was a significant determinant of total lifetime reproductive success in males, with heavier-born males being more successful than lighter ones. In contrast, birthweight did not affect female reproductive success. High population density and cold spring temperatures in the year of birth decreased several components of fitness in females, but did not affect the breeding success of males. The results confirm the prediction that selection on a sexually dimorphic trait should be greater in males than in females, and explain the differential maternal expenditure between sons and daughters observed in red deer. Differences between the sexes in the effects of environmental and phenotypic variation on fitness may generate differences in the amount of heritable genetic variation underlying traits such as birthweight.  (+info)

Neanderthal cannibalism at Moula-Guercy, Ardeche, France. (27/1110)

The cave site of Moula-Guercy, 80 meters above the modern Rhone River, was occupied by Neanderthals approximately 100,000 years ago. Excavations since 1991 have yielded rich paleontological, paleobotanical, and archaeological assemblages, including parts of six Neanderthals. The Neanderthals are contemporary with stone tools and faunal remains in the same tightly controlled stratigraphic and spatial contexts. The inference of Neanderthal cannibalism at Moula-Guercy is based on comparative analysis of hominid and ungulate bone spatial distributions, modifications by stone tools, and skeletal part representations.  (+info)

The molecular genetics of red and green color vision in mammals. (28/1110)

To elucidate the molecular mechanisms of red-green color vision in mammals, we have cloned and sequenced the red and green opsin cDNAs of cat (Felis catus), horse (Equus caballus), gray squirrel (Sciurus carolinensis), white-tailed deer (Odocoileus virginianus), and guinea pig (Cavia porcellus). These opsins were expressed in COS1 cells and reconstituted with 11-cis-retinal. The purified visual pigments of the cat, horse, squirrel, deer, and guinea pig have lambdamax values at 553, 545, 532, 531, and 516 nm, respectively, which are precise to within +/-1 nm. We also regenerated the "true" red pigment of goldfish (Carassius auratus), which has a lambdamax value at 559 +/- 4 nm. Multiple linear regression analyses show that S180A, H197Y, Y277F, T285A, and A308S shift the lambdamax values of the red and green pigments in mammals toward blue by 7, 28, 7, 15, and 16 nm, respectively, and the reverse amino acid changes toward red by the same extents. The additive effects of these amino acid changes fully explain the red-green color vision in a wide range of mammalian species, goldfish, American chameleon (Anolis carolinensis), and pigeon (Columba livia).  (+info)

Loading conditions and cortical bone construction of an artiodactyl calcaneus. (29/1110)

Customary nonuniform distributions of physiological bone strains are thought to evoke heterogeneous material adaptation in diaphyseal cortices of some limb bones. Recent studies of artiodactyl calcanei have suggested that the regional prevalence of specific mechanical strain features such as mode and magnitude correlate with specific variations in cortical bone ultrastructure, microstructure and mineralization. These data are also consistent with predictions of current algorithms of mechanically induced bone adaptation. However, detailed characterization of the customary functional strain environment of these bones is needed to understand better the mechanisms of these adaptations. An in vitro loading method and rosette strain gauges were used to record principal strains, maximum shear strains and principal strain angles at multiple locations on ten calcanei of adult male mule deer (Odocoileus hemionus hemionus). Each hind limb was fixed in an apparatus to mimic the mid-support phase of the gait and loaded via the Achilles tendon over a broad range of functional loads (0 to 2943 N). Strains were recorded on the craniolateral, craniomedial, caudal, medial and lateral cortices at mid-diaphysis. Loading variations included the progressive elimination of the ligament and tendon along the caudal calcaneus. The results showed that the cranial cortex experiences longitudinal compressive strains that are nearly equal to the principal minimum strains and that the caudal cortex receives longitudinal tensile strains that are nearly equal to the principal maximum strains. With a 981 N load, the mean principal compressive strain on the cranial cortex was -636+/-344 micro(&egr;) (mean +/- s.d., N=9) and the mean principal tensile strain on the caudal cortex was 1112+/-68 micro;(&egr;)x (N=9). In contrast to the cranial and caudal cortices, principal strains in the medial and lateral cortices displayed relatively large deviations from the longitudinal axis (medial, 24 degrees cranial; lateral, 27 degrees caudal). Although shear strains predominated at all gauge sites, variations in maximum shear strains showed no apparent regional pattern or consistent regional predominance. The plantar ligament and tendon of the superficial digital flexor muscle were shown to have important load-sharing functions. These results demonstrate that the functionally loaded artiodactyl calcaneus generally behaves like a cantilevered beam with longitudinal compression and tension strains predominating in opposing cranial and caudal cortices, respectively. Differences in osteon remodeling rates, osteon morphology and mineral content reported previously between the cranial and caudal cortices correlate, in part, with the magnitudes of the principal compressive and tensile strains, respectively. However, material differences that distinguish the medial and lateral cortices from the cranial and caudal cortices could not be primarily attributed to locally increased shear strains as previously suggested. Variations in osteon and/or collagen fiber orientation may correlate more strongly with principal strain direction.  (+info)

Application of a DNA hybridization-hydrophobic-grid membrane filter method for detection and isolation of verotoxigenic escherichia coli. (30/1110)

Verotoxigenic Escherichia coli (VTEC) strains were isolated from food and animal fecal samples by using PCR to screen for the presence of VTEC after broth enrichment and then filtering VTEC-positive cultures through hydrophobic-grid membrane filters (HGMFs) which were incubated on MacConkey agar. The filters were probed with a digoxigenin-labeled PCR product generated by amplification of a conserved verotoxin gene sequence. Replication of the growth on filters allowed probe-positive colonies to be picked. When ground beef samples were inoculated with VTEC strains, 100% of the strains were recovered, and the detection limit was 0.1 CFU per g. Similar results were obtained with seven types of artificially contaminated vegetables. A survey of 32 packages of vegetables and 23 samples of apple cider obtained at the retail level did not reveal the presence of VTEC. However, the intestinal fecal contents of a moose, 1 of 35 wild mammals and birds examined, contained E. coli O157:H7. The DNA hybridization-HGMF method was also used in a prevalence survey of 327 raw and 744 ready-to-eat products; VTEC strains were recovered from 4.9% of the raw products and 0.7% of the ready-to-eat products. No serotype O157:H7 strains were detected. This method is particularly suited for surveys in which low numbers of VTEC-positive samples are expected and isolates are required.  (+info)

Oral transmission and early lymphoid tropism of chronic wasting disease PrPres in mule deer fawns (Odocoileus hemionus). (31/1110)

Mule deer fawns (Odocoileus hemionus) were inoculated orally with a brain homogenate prepared from mule deer with naturally occurring chronic wasting disease (CWD), a prion-induced transmissible spongiform encephalopathy. Fawns were necropsied and examined for PrPres, the abnormal prion protein isoform, at 10, 42, 53, 77, 78 and 80 days post-inoculation (p.i.) using an immunohistochemistry assay modified to enhance sensitivity. PrPres was detected in alimentary-tract-associated lymphoid tissues (one or more of the following: retropharyngeal lymph node, tonsil, Peyer's patch and ileocaecal lymph node) as early as 42 days p.i. and in all fawns examined thereafter (53 to 80 days p.i.). No PrPres staining was detected in lymphoid tissue of three control fawns receiving a control brain inoculum, nor was PrPres detectable in neural tissue of any fawn. PrPres-specific staining was markedly enhanced by sequential tissue treatment with formic acid, proteinase K and hydrated autoclaving prior to immunohistochemical staining with monoclonal antibody F89/160.1.5. These results indicate that CWD PrPres can be detected in lymphoid tissues draining the alimentary tract within a few weeks after oral exposure to infectious prions and may reflect the initial pathway of CWD infection in deer. The rapid infection of deer fawns following exposure by the most plausible natural route is consistent with the efficient horizontal transmission of CWD in nature and enables accelerated studies of transmission and pathogenesis in the native species.  (+info)

PrP genotypes of captive and free-ranging Rocky Mountain elk (Cervus elaphus nelsoni) with chronic wasting disease. (32/1110)

The PrP gene encodes the putative causative agent of the transmissible spongiform encephalopathies (TSEs), a heterogeneous group of fatal, neurodegenerative disorders including human Creutzfeldt-Jakob disease, bovine spongiform encephalopathy, ovine scrapie and chronic wasting disease (CWD) of North American deer and elk. Polymorphisms in the PrP gene are associated with variations in relative susceptibility, pathological lesion patterns, incubation times and clinical course of TSEs of humans, mice and sheep. Sequence analysis of the PrP gene from Rocky Mountain elk showed only one amino acid change (Met to Leu at cervid codon 132). Homozygosity for Met at the corresponding polymorphic site (Met to Val) in humans (human codon 129) predisposes exposed individuals to some forms of Creutzfeldt-Jakob disease. In this study, Rocky Mountain elk homozygous for PrP codon 1 32 Met were over-represented in both free-ranging and farm-raised CWD-affected elk when compared to unaffected control groups.  (+info)