Radio harness system for bobcat kittens

Eight bobcat kittens were fitted with a specially designed harness system supporting a radio transmitter. These kittens were the youngest known to be radio-instrumented. This system was used successfully through two seasons, from June 1989 to January 1991. Litters of kittens were located soon after birth for weighing, marking, and aging (by tooth eruption). During the first year when kittens were at least eight weeks old and six weeks old the second year, attempts were made to radio-instrument kittens in each litter. This harness system allowed litters to be located periodically until their death or dispersal. We were able to collect important data during the most crucial and least known weeks of the lives of bobcat kittens.     

Salvage logging and replanting reduce understory cover and richness compared to unsalvaged unplanted sites at Mount St. Helens, Washington

The 1980 eruption of Mount St. Helens killed trees in a broad 600-km2 swath north of the crater. Over most of the blast zone, dead trees were salvage logged and Abies procera was planted, except in areas within the Mount St. Helens National Volcanic Monument. We compared salvage-replanted sites and unsalvaged sites in 1 area of the blast zone where the sites were adjacent by using twenty-five 200-m 2 plots for each treatment. Salvaged-replanted plots had significantly lower herb and shrub cover, richness, diversity, litter depth, downed woody debris, nitrate, and phosphate. Salvaged-replanted sites also had significantly more stumps, bare area, and moss cover than unsalvaged plots. Soil organic matter and nonnative species cover did not differ. Nonnative species were not important components of any plots. Nitrate, total nitrogen, organic matter, and litter were correlated with the major patterns of species distribution in a canonical correspondence analysis of the salvaged-replanted plots. In the unsalvaged plots, slope, downed woody debris, and elevation were correlated with the major patterns of species distribution.     

Pilfering of stored seeds and the relative costs of scatter-hoarding versus larder-hoarding in yellow pine chipmunks

Yellow pine chipmunks ( Tamias amoenus ) scatter-hoard food during summer and autumn but must form a larder as a winter food source before winter begins. Yellow pine chipmunks do not larder-hoard large quantities of food during the summer, apparently because a summer larder could not be defended from pilferers. We tested the assumption that the rate of pilferage from an unguarded larder would be significantly greater than the rate of pilferage from surface caches (which are also unguarded by yellow pine chipmunks) during the summer and autumn. Buried plastic buckets were used as artificial nests containing larders of 1000 sunflower seeds or 200 Jeffrey pine ( Pinus jeffreyi ) seeds. The pilferage of larder contents was monitored daily and compared to pilferage of surface caches. Animals (yellow pine chipmunks and deer mice, Peromyscus maniculatus ) removed sunflower seeds from caches much faster than from larders, but caches of Jeffrey pine seeds disappeared much more slowly than pine seeds in larders. Further, animals removed pine seeds from larders more quickly than they did sunflower seeds from larders. The difference between seed species was probably because sunflower seeds have much stronger odors, which rodents readily detect, and because chipmunks prefer pine seeds over sunflower seeds. Yellow pine chipmunks must spend a considerable portion of their time foraging for seeds and may not be able to defend a large larder during summer.     

Varying prevalence of Taenia taeniaeformis strobilocerci in Microtus pennsylvanicus of Montana

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Of 42 Microtus pennsylvanicus trapped 1 km from Bozeman, Montana, 14 (33.3 percent) were infected by strobilocerci of Taenia taeniaeformis, while only one (2.1 percent) of 47 was infected at a rural site 16 km from Bozeman. The higher incidence of the primary host, domestic cats, is believed to account for the higher rate of infection near Bozeman.     

Correlates of burrow location in Beechey ground squirrels

Partial correlation analysis indicates that Beechey ground squirrels show a strong preference for digging burrows under and around large objects, may show a weaker tendency to locate their burrows under the cover of tree canopies, and avoid digging burrows in areas with both treecanopy and ground cover (stones, logs). These relationships hold for large but not small burrow systems. The need for unobstructed visual surveillance and an autumn food supply are proposed to be determinants of these preferences.     

Lahontan sagebrush ( Artemisia arbuscula ssp. longicaulis ): a new taxon

A new subspecies of Artemisia arbuscula is described, A. arbuscula ssp. longicaulis Winward & McArthur, ssp. Nov. This taxon is a landscape dominant in portions of northwestern Nevada and adjacent California and Oregon at elevations from 1050 to 2000 m on shallow or argillic (clayey) soils. It differs from A. arbuscula ssp. arbuscula in its long floral stalks and large leaves. Morphological, chemical, ecological, and cytological data suggest that it is of hybrid origin. It is hexaploid (6x). We hypothesize that 2x A. arbusucla ssp. arbusucla and 4x A. tridentata ssp. wyomingensis are its parents.     

Shorebird predation on benthic macroinvertebrates in an irrigation reservoir

American Falls Reservoir in southeastern Idaho is an irrigation reservoir used as an inland feeding stopover by many shorebird species. Six exclosure experiments were conducted during the 1990 drawdown period to investigate shorebird predation impact on benthic macroinvertebrate populations. The study sites differed in sediment composition, sediment slope, invertebrate densities, and shorebird abundance. Shorebird predation significantly affected invertebrate densities in only 1 of 6 experiments (Aberdeen Mouth). This site had higher sediment slope and a lower water recedence than other study sites, resulting in concentration of shorebird predation on a small area of newly exposed sediment. Shorebird predation had the greatest impact on medium size class chironomid larvae at Aberdeen Mouth. Our results suggest that inland sites such as American Falls Reservoir represent viable shorebird habitat and may be managed to insure consistent prey availability. Drawdown rate, sediment slope, invertebrate densities, and shorebird abundance are all important factors influencing shorebird predation. Monitoring shorebird abundance and predation impact on invertebrate densities may help in manipulating drawdown rate to provide adequate shorebird prey. Management of inland sites for shorebird use may become more important in the future as human encroachment in coastal areas continues.     

Protein arginine deiminase 4: a target for an epigenetic cancer therapy

The recent approvals of anticancer therapeutic agents targeting the histone deacetylases and DNA methyltransferases have highlighted the important role that epigenetics plays in human diseases, and suggested that the factors controlling gene expression are novel drug targets. Protein arginine deiminase 4 (PAD4) is one such target because its effects on gene expression parallel those observed for the histone deacetylases. We demonstrated that F- and Cl-amidine, two potent PAD4 inhibitors, display micromolar cytotoxic effects towards several cancerous cell lines (HL-60, MCF7 and HT-29); no effect was observed in noncancerous lines (NIH 3T3 and HL-60 granulocytes). These compounds also induced the differentiation of HL-60 and HT29 cells. Finally, these compounds synergistically potentiated the cell killing effects of doxorubicin. Taken together, these findings suggest PAD4 inhibition as a novel epigenetic approach for the treatment of cancer, and suggest that F- and Cl-amidine are candidate therapeutic agents for this disease.     

Identification of a bacterial inhibitor against g-type lysozyme

Lysozymes are antibacterial effectors of the innate immune system in animals that hydrolyze peptidoglycan. Bacteria have evolved protective mechanisms that contribute to lysozyme tolerance such as the production of lysozyme inhibitors, but only inhibitors of chicken (c-) and invertebrate (i-) type lysozyme have been identified. We here report the discovery of a novel Escherichia coli inhibitor specific for goose (g-) type lysozymes, which we designate PliG (periplasmic lysozyme inhibitor of g-type lysozyme). Although it does not inhibit c- or i-type lysozymes, PliG shares a structural sequence motif with the previously described PliI and MliC/PliC lysozyme inhibitor families, suggesting a common ancestry and mode of action. Deletion of pliG increased the sensitivity of E. coli to g-type lysozyme. The existence of inhibitors against all major types of animal lysozyme and their contribution to lysozyme tolerance suggest that lysozyme inhibitors may play a role in bacterial interactions with animal hosts.     

Molecular basis of parathyroid hormone receptor signaling and trafficking: a family B GPCR paradigm

The parathyroid hormone (PTH) receptor type 1 (PTHR), a G protein-coupled receptor (GPCR), transmits signals to two hormone systems—PTH, endocrine and homeostatic, and PTH-related peptide (PTHrP), paracrine—to regulate different biological processes. PTHR responds to these hormonal stimuli by activating heterotrimeric G proteins, such as G_S that stimulates cAMP production. It was thought that the PTHR, as for all other GPCRs, is only active and signals through G proteins on the cell membrane, and internalizes into a cell to be desensitized and eventually degraded or recycled. Recent studies with cultured cell and animal models reveal a new pathway that involves sustained cAMP signaling from intracellular domains. Not only do these studies challenge the paradigm that cAMP production triggered by activated GPCRs originates exclusively at the cell membrane but they also advance a comprehensive model to account for the functional differences between PTH and PTHrP acting through the same receptor.