Gamma-Irradiated Cornea in Combat-related Ocular Trauma.

Corneal injury is a known risk for deployed troops worldwide. To the authors' knowledge, there has been no reported use of gamma-irradiated corneas in the setting of severe corneal trauma. Our report highlights the case of a 36-year-old active duty solider who sustained bilateral penetrating ocular trauma from a nearby ordnance explosion. We propose that ocular surgeons should consider utilizing gamma-irradiated corneas in (1) a situation where the corneal tissue is so damaged that it would be challenging to accomplish an adequate repair while providing the opportunity for future visual rehabilitation and (2) remote and/or deployed environments where storage of fresh donor tissue is limited. The long shelf life of gamma-irradiated corneas reduces the need for specialized storage equipment and the need for continuous resupply, both potentially leading to significant cost savings for the Military Health System.

Carotid Endarterectomy for Ocular Ischemic Syndrome: A Case Report and Review of the Literature.

Ocular ischemic syndrome is a rare complication of carotid arterial disease that can lead to irreversible vision loss. The disease is related to ocular hypoperfusion secondary to carotid stenosis. Carotid endarterectomy (CEA) has been proven to reduce the risk of embolic stroke in specific patient populations; however, the role of CEA in the treatment of ocular ischemic syndrome or other flow-related symptoms is less well defined. We present a case of ocular ischemic syndrome successfully treated with carotid endarterectomy, and summarize the current literature regarding management of ocular ischemic syndrome.

The Role of Scent Marking in Mate Selection by Female Pumas (Puma concolor).

Mate selection influences individual fitness, is often based on complex cues and behaviours, and can be difficult to study in solitary species including carnivores. We used motion-triggered cameras at 29 community scrapes (i.e. scent marking locations used by multiple individuals) and home range data from 39 GPS-collared pumas (Puma concolor) to assess the relevance of communication behaviours for mate selection by female pumas in California. Female pumas visited community scrapes irregularly and visitation bouts appeared to be correlated with oestrus. Female pumas on average selected from 1.7 collared males, and selection was based on multiple cues that varied among the different time periods measured (i.e. the female's visitation bout and in 90 days previous to the consorting event). Female mate selection over the course of a visitation bout was based on frequency of the male visitation, mass, and age. In the 90 days previous to consorting, the number of scrapes a male created was the most important contributor to selection, which was likely related to his residency status. We also found that at least 14% of females mated with multiple males, thus possibly confusing paternity. Our findings provide a mechanistic understanding of how female pumas use scent and auditory communication at community scrapes to select dominant resident males to mate with.

Scale dependent behavioral responses to human development by a large predator, the puma.

The spatial scale at which organisms respond to human activity can affect both ecological function and conservation planning. Yet little is known regarding the spatial scale at which distinct behaviors related to reproduction and survival are impacted by human interference. Here we provide a novel approach to estimating the spatial scale at which a top predator, the puma (Puma concolor), responds to human development when it is moving, feeding, communicating, and denning. We find that reproductive behaviors (communication and denning) require at least a 4× larger buffer from human development than non-reproductive behaviors (movement and feeding). In addition, pumas give a wider berth to types of human development that provide a more consistent source of human interference (neighborhoods) than they do to those in which human presence is more intermittent (arterial roads with speeds >35 mph). Neighborhoods were a deterrent to pumas regardless of behavior, while arterial roads only deterred pumas when they were communicating and denning. Female pumas were less deterred by human development than males, but they showed larger variation in their responses overall. Our behaviorally explicit approach to modeling animal response to human activity can be used as a novel tool to assess habitat quality, identify wildlife corridors, and mitigate human-wildlife conflict.

Zebrafish msxB, msxC and msxE function together to refine the neural-nonneural border and regulate cranial placodes and neural crest development.

The zebrafish muscle segment homeobox genes msxB, msxC and msxE are expressed in partially overlapping domains in the neural crest and preplacodal ectoderm. We examined the roles of these msx genes in early development. Disrupting individual msx genes causes modest variable defects, whereas disrupting all three produces a reproducible severe phenotype, suggesting functional redundancy. Neural crest differentiation is blocked at an early stage. Preplacodal development begins normally, but placodes arising from the msx expression domain later show elevated apoptosis and are reduced in size. Cell proliferation is normal in these tissues. Unexpectedly, Msx-deficient embryos become ventralized by late gastrulation whereas misexpression of msxB dorsalizes the embryo. These effects appear to involve Distal-less (Dlx) protein activity, as loss of dlx3b and dlx4b suppresses ventralization in Msx-depleted embryos. At the same time, Msx-depletion restores normal preplacodal gene expression to dlx3b-dlx4b mutants. These data suggest that mutual antagonism between Msx and Dlx proteins achieves a balance of function required for normal preplacodal differentiation and placement of the neural-nonneural border.