Computational Design of Phosphotriesterase Improves V-Agent Degradation Efficiency.

Organophosphates (OPs) are a class of neurotoxic acetylcholinesterase inhibitors including widely used pesticides as well as nerve agents such as VX and VR. Current treatment of these toxins relies on reactivating acetylcholinesterase, which remains ineffective. Enzymatic scavengers are of interest for their ability to degrade OPs systemically before they reach their target. Here we describe a library of computationally designed variants of phosphotriesterase (PTE), an enzyme that is known to break down OPs. The mutations G208D, F104A, K77A, A80V, H254G, and I274N broadly improve catalytic efficiency of VX and VR hydrolysis without impacting the structure of the enzyme. The mutation I106 A improves catalysis of VR and L271E abolishes activity, likely due to disruptions of PTE's structure. This study elucidates the importance of these residues and contributes to the design of enzymatic OP scavengers with improved efficiency.

Assessment of multiple herbicide protection seed treatments for seed-based restoration of native perennial bunchgrasses and sagebrush across multiple sites and years.

The invasion of exotic, annual plant species is a leading contributor to ecological degradation in drylands globally, and the use of pre-emergent herbicide to control these species is common. Pre-emergent herbicides pose challenges for seed-based restoration due to toxicity to the seeds of desired species. Herbicide protection (HP) technologies pose a potential solution by using activated carbon seed treatments to protect desirable seeds from herbicide exposure. In the sagebrush steppe ecosystem of North America, we used an adaptive small plot design over three planting years to test for effects on seeding outcomes (seedling density and size) of large and small multi-seed HP pellets, several single-seed HP coatings, and carbon banding treatments at geographically dispersed sites for several perennial bunchgrasses and the keystone perennial shrub, Wyoming big sagebrush. We also compared different methods of seed delivery and litter pre-seeding management. Seeding success was low overall, especially for sagebrush, and it was clear that other, often less predictable barriers to establishment than herbicide exposure, such as inadequate spring moisture, were strong drivers of seeding outcomes. Despite this, HP treatments were associated with higher seedling density than bare seed in multiple instances, most notably for grasses. The large HP pellet occasionally outperformed the small HP pellet, and several HP coatings performed similarly to the small pellet. Surprisingly, we did not see consistent negative effects of pre-emergent herbicide on unprotected bare seed. We conclude that HP seed treatments show some promise to improve seeding success in the presence of herbicide, but that consistent success will require further improvements to HP treatments as well as integration with other innovations and approaches.

Spinal cord infarction attributed to SARS-CoV-2, with post-acute sequelae of COVID-19: A case report.

BACKGROUND: While stroke and lower extremity venous thromboemboli have been commonly reported following acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spinal cord infarction or ischemia has been extremely rare. Findings of long coronavirus disease (COVID) in this select population have not been studied. CASE SUMMARY: We present the case of a 70-year-old female with sudden onset of trunk and lower extremity sensorimotor loss due to spinal cord infarction, attributed to acute infection with SARS-CoV-2. Diagnostic work up confirmed a T3 complete (ASIA impairment Scale A) paraplegia resulting from a thrombotic infarct. Her reported myalgias, neuropathic pain, spasticity, bladder spasms, and urinary tract infections exceeded the frequency and severity of many spinal cord injury (SCI) individuals of similar age and degree of neurologic impairment. In her first year after contracting COVID-19, she underwent 2 separate inpatient rehabilitation courses, but also required acute hospitalization 6 additional times for subsequent infections or uncontrolled pain. Yet other complications of complete non-traumatic SCI (NTSCI), including neurogenic bowel and temperature hypersensitivity, were mild, and pressure injuries were absent. She has now transitioned from the acute to chronic phase of spinal cord injury care, with subsequent development of post-acute sequelae of SARS-CoV-2 infection (PASC). CONCLUSION: This individual experienced significant challenges with the combined effects of acute T3 NTSCI and acute COVID-19, with subsequent progression to PASC.

Next-generation technologies unlock new possibilities to track rangeland productivity and quantify multi-scale conservation outcomes.

Historically, relying on plot-level inventories impeded our ability to quantify large-scale change in plant biomass, a key indicator of conservation practice outcomes in rangeland systems. Recent technological advances enable assessment at scales appropriate to inform management by providing spatially comprehensive estimates of productivity that are partitioned by plant functional group across all contiguous US rangelands. We partnered with the Sage Grouse and Lesser Prairie-Chicken Initiatives and the Nebraska Natural Legacy Project to demonstrate the ability of these new datasets to quantify multi-scale changes and heterogeneity in plant biomass following mechanical tree removal, prescribed fire, and prescribed grazing. In Oregon's sagebrush steppe, for example, juniper tree removal resulted in a 21% increase in one pasture's productivity and an 18% decline in another. In Nebraska's Loess Canyons, perennial grass productivity initially declined 80% at sites invaded by trees that were prescriptively burned, but then fully recovered post-fire, representing a 492% increase from nadir. In Kansas' Shortgrass Prairie, plant biomass increased 4-fold (966,809 kg/ha) in pastures that were prescriptively grazed, with gains highly dependent upon precipitation as evidenced by sensitivity of remotely sensed estimates (SD ± 951,308 kg/ha). Our results emphasize that next-generation remote sensing datasets empower land managers to move beyond simplistic control versus treatment study designs to explore nuances in plant biomass in unprecedented ways. The products of new remote sensing technologies also accelerate adaptive management and help communicate wildlife and livestock forage benefits from management to diverse stakeholders.

Delays in the Identification and Assessment of in-Hospital Stroke Patients.

OBJECTIVES: In-hospital stroke is associated with poor outcomes. Reasons for delays, use of interventions, and presence of large vessel occlusion are not well characterized. MATERIALS AND METHODS: A retrospective single center cohort of 97 patients with in-hospital stroke was analyzed to identify factors associated with delays from last known normal to symptom identification and to stroke team alerting. Stroke interventions and presence of large vessel occlusion were also assessed. RESULTS: Strokes were predominantly on surgery services (70%), ischemic (82%), and severe (median NIHSS 16; interquartile range [IQR] 6-24). There were long delays from last known normal to symptom identification (median 5.1 hours, IQR 1.0-19.7 hours), symptom identification to stroke team alerting (median 2.1 hours, IQR 0.5-9.9 hours), and total time from last known normal to alerting (median 11.4 [IQR 2.7-34.2] hours). In univariable analysis, being on a surgical service, in an ICU, intubated, and higher NIHSS were associated with delays. In multivariable analysis only intubation was independently associated with time from last known normal to symptom identification (coefficient 20 hours, IQR 0.2 - 39.8, p=0.047). Interventions were given to 17/80 (21%) ischemic stroke patients; 3 (4%) received IV tPA and 14 (18%) underwent thrombectomy. Vascular imaging occurred in 57/80 (71%) ischemic stroke patients and 21/57 (37%) had large vessel occlusion. CONCLUSIONS: Hospitalized patients with stroke experience long delays from symptom identification to stroke team alerting. Intubation was strongly associated with delay to symptom identification. Although stroke severity was high and large vessel occlusion common, many patients did not receive acute interventions.

Tracking spatial regimes as an early warning for a species of conservation concern.

In this era of global environmental change and rapid regime shifts, managing core areas that species require to survive and persist is a grand challenge for conservation. Wildlife monitoring data are often limited or local in scale. The emerging ability to map and track spatial regimes (i.e., the spatial manifestation of state transitions) using advanced geospatial vegetation data has the potential to provide earlier warnings of habitat loss because many species of conservation concern strongly avoid spatial regime boundaries. Using 23 yr of data for the lek locations of Greater Prairie-Chicken (Tympanuchus cupido; GPC) in a remnant grassland ecosystem, we demonstrate how mapping changes in the boundaries between grassland and woodland spatial regimes provide a spatially explicit early warning signal for habitat loss for an iconic and vulnerable grassland-obligate known to be highly sensitive to woody plant encroachment. We tested whether a newly proposed metric for the quantification of spatial regimes captured well-known responses of GPC to woody plant expansion into grasslands. Resource selection functions showed that the grass:woody spatial regime boundary strength explained the probability of 80% of relative lek occurrence, and GPC strongly avoided grass:woody spatial regime boundaries at broad scales. Both findings are consistent with well-known expectations derived from GPC ecology. These results provide strong evidence for vegetation-derived delineations of spatial regimes to serve as generalized signals of early warning for state transitions that have major consequences to biodiversity conservation. Mapping spatial regime boundaries over time provided interpretable early warnings of habitat loss. Woody plant regimes displaced grassland regimes starting from the edges of the study area and constricting inward. Correspondingly, the relative probability of lek occurrence constricted in space. Similarly, the temporal trajectory of spatial regime boundary strength increased over time and moved closer to the observed limit of GPC lek site usage relative to grass:woody boundary strength. These novel spatial metrics allow managers to rapidly screen for early warning signals of spatial regime shifts and adapt management practices to defend and grow habitat cores at broad scales.

Biomanufacturing of value-added products from oils or fats: A case study on cellular and fermentation engineering of Yarrowia lipolytica.

The United States produces more than 10 million tons of waste oils and fats each year. This paper aims to establish a new biomanufacturing platform that converts waste oils or fats into a series of value-added products. Our research employs the oleaginous yeast Yarrowia lipolytica as a case study for citric acid (CA) production from waste oils. First, we conducted the computational fluid dynamics (CFD) simulation of the bioreactor system and identified that the extracellular mixing and mass transfer is the first limiting factor of an oil fermentation process due to the insolubility of oil in water. Based on the CFD simulation results, the bioreactor design and operating conditions were optimized and successfully enhanced oil uptake and bioconversion in fed-batch fermentation experiments. After that, we investigated the impacts of cell morphology on oil uptake, intracellular lipid accumulation, and CA formation by overexpressing and deleting the MHY1 gene in the wild type Y. lipolytica ATCC20362. Fairly good linear correlations (R2 > 0.82) were achieved between cell morphology and productivities of biomass, lipid, and CA. Finally, fermentation kinetics with both glucose and oil substrates were compared and the oil fermentation process was carefully evaluated. Our study suggests that waste oils or fats can be economical feedstocks for biomanufacturing of many high-value products.

Mismatch between automated CTP and ASPECTS score in patients with anterior large vessel occlusion.

OBJECTIVES: To evaluate the relationship between delay to computed tomography perfusion and estimated core infarct volumes in patients with large vessel occlusion (LVO). PATIENTS AND METHODS: A retrospective registry of consecutive adults >18 years old who underwent CTP in clinical practice for suspected LVO within 24 h of LKN at 3 academic hospitals was queried (06/2017 - 12/2017). CT and CTP findings were compared over time as a continuous variable, and dichotomized by ≤6 h or 6-24 h from LKN. RESULTS: Of 410 screened patients, 75 had LVO, of whom 60 (14.6 %) met inclusion criteria (median age 78y [IQR 64-84], 36 were female [60 %]), and 39 (65.0 %) underwent thrombectomy. Thirty (50 %) presented in the extended window (6-24 h) and had lower ASPECTS scores compared to patients in the early window (median 7 vs. 9, p < 0.01). Perfusion core (rCBF <30 %) volumes were similar (median 8 vs. 25, p = 0.10). After adjustment for age, NIHSS, and thrombolysis, there was a trend for lower ASPECTS for every hour after LKN (proportional OR 0.92, 95 %CI 0.84-1.00, p = 0.06), but no change in perfusion core (p = 0.37) or Tmax>6 s volumes (p = 0.29), or mismatch ratios (p = 0.48) after adjusting for age, NIHSS, ASPECTS, and thrombolysis. CONCLUSION: As time progresses in anterior LVO, the unenhanced CT is more sensitive than CTP for detecting irreversibly damaged tissue. These results underscore the importance of carefully reviewing the unenhanced and perfusion CT when considering a patient for thrombectomy.

Computed tomography perfusion in stroke mimics.

OBJECTIVE: To describe the prevalence and patterns of abnormal findings on automated computed tomography perfusion in patients with stroke mimic. METHODS: We reviewed a retrospective multi-site cohort of consecutive patients undergoing computed tomography perfusion for suspected acute ischemic stroke within 24 h from last normal (June 2017 to December 2017). The primary outcome was the diagnosis of stroke mimic. Hypoperfusion abnormalities on iSchemaView RAPID automated computed tomography perfusion were compared between patients with stroke/transient ischemic attack and stroke mimic using mixed-effects multivariable logistic regression, focusing on absence of perfusion abnormalities and discordance with clinical symptoms and computed tomography angiography findings. RESULTS: Of 410 consecutive patients who underwent computed tomography perfusion, 348 met inclusion criteria (178 (51%) stroke, 19 (6%) transient ischemic attack, and 151 (43%) mimic). Time-to-maximum of the tissue residue function (Tmax>6s) abnormalities were seen in 42 (28%) patients with stroke mimic and 122 (62%) patients with stroke/transient ischemic attack (p < 0.001). Patients with stroke mimic were more likely to have a normal Tmax pattern (volume = 0mL; adjusted OR: 2.2, 95% CI: 1.1-4.3, p = 0.02). When the Tmax pattern was abnormal, a higher proportion of patients with stroke mimic had Tmax patterns fully discordant with clinical symptoms than patients with stroke/transient ischemic attack (28/39 (71%) vs. 10/115 (9%), p < 0.001). Fully discordant Tmax abnormalities were strongly associated with stroke mimic (adjusted OR: 48.6, 95% CI: 7.0-336, p < 0.001), with a negative predictive value for identifying mimic of 91% (95% CI: 85-94%). CONCLUSION: While one-quarter of patients with stroke mimic show Tmax abnormalities on automated RAPID computed tomography perfusion imaging, the majority of patterns were discordant with symptoms and vessel status. Normal or fully discordant Tmax abnormalities are were more common with stroke mimic and may inform stroke treatment decision making.

Pancreatic Islets Accumulate Cadmium in a Rodent Model of Cadmium-Induced Hyperglycemia.

Cadmium (Cd) is an anthropogenic as well as a naturally occurring toxicant associated with prediabetes and T2DM in humans and experimental models of Cd exposure. However, relatively few studies have examined the mechanism(s) of Cd-induced hyperglycemia. The purpose of this study was to examine the role of pancreatic islets in Cd-induced hyperglycemia. Male Sprague-Dawley rats were given daily subcutaneous doses of Cd at 0.6 mg/kg over 12 weeks. There was a resulting time-dependent increase in fasting blood glucose and altered insulin release in vitro. Islets isolated from control (saline-treated) and Cd-treated animals were incubated in low (0.5 mg/mL) or high (3 mg/mL) glucose conditions. Islets from 12 week Cd-treated animals had significantly less glucose-stimulated insulin release compared to islets from saline-treated control animals. The actual Cd content of isolated islets was 5 fold higher than the whole pancreas (endocrine + exocrine) and roughly 70% of that present in the renal cortex. Interestingly, islets isolated from Cd-treated animals and incubated in high glucose conditions contained significantly less Cd and zinc than those incubated in low glucose. These results show that within whole pancreatic tissue, Cd selectively accumulates in pancreatic islets and causes altered islet function that likely contributes to dysglycemia.

Multicenter Volumetric Assessment of Artifactual Hypoperfusion Patterns using Automated CT Perfusion Imaging.

BACKGROUND AND PURPOSE: Automated computed tomography perfusion (CTP) is recommended to inform selection of stroke patients for thrombectomy >6 hours from last known normal (LKN). However, artifacts on automated perfusion output may overestimate the tissue at risk leading to misclassification of thrombectomy eligibility in some patients. METHODS: We conducted a retrospective multisite study of consecutive patients with anterior large vessel occlusion (LVO) undergoing CTP (6/2017-12/2017). The primary outcome was the RAPID automated Tmax  > 6 seconds volume that was discordant with clinical symptoms and vessel imaging, manually assessed by two independent readers. The discordant penumbral volume was compared to the automated output and corrected mismatch ratios were generated. RESULTS: Of 410 consecutive patients who underwent CTP for suspected stroke, 60 (15%) had acute anterior circulation LVO. Of these, 26 (43%) had Tmax > 6 seconds abnormalities discordant with clinical symptoms and vessel imaging. There was strong interrater agreement on artifact volume (r2 = 0.927). Among patients with discordant Tmax imaging, the median artifactual volume was 12cc (IQR 3-21cc), accounting for a median of 8% of the automated Tmax > 6 seconds volume (IQR 3-16%, range 1-64%). Recalculation of the Tmax > 6 seconds volume resulted in 1 patient being reclassified as having an "unfavorable" mismatch ratio (2.04-1.40). CONCLUSION: Nearly half of patients had evidence of artifactual penumbral imaging on automated CTP, which rarely lead to misclassification of thrombectomy eligibility. Although artifactual findings are reliably identified by trained raters, our results emphasize the need to evaluate CTP results with knowledge of the patient's clinical symptoms and vascular imaging.

Is there any diagnostic value of anteroposterior chest radiography in predicting cardiac chamber enlargement?

The anteroposterior (AP) portable chest radiograph is routinely performed to evaluate cardiopulmonary status, however heart size can be misrepresented by inherent technical factors. Our aim was to determine diagnostic accuracy of cardiothoracic ratio (CTR) on AP chest radiographs relative to echocardiography, as well as relative to axial computed tomography (CT) and frontal CT scout images in predicting cardiac chamber enlargement. 200 subjects with both chest CT and AP chest radiograph within 1 month were retrospectively identified. Patients with pericardial effusion or obscured heart borders were excluded. 130 of these subjects had also undergone echocardiography. Transverse diameters of the heart and thorax were used to calculate CTRs on AP chest radiograph, scout CT, and axial CT images. A second reader was used to verify measurement accuracy and reproducibility. Statistical analysis of CTRs for AP chest radiograph, CT scout, and axial CT images were calculated using echocardiography as gold standard. AP chest radiographs had higher CTR values than axial and scout CT images (by 0.075, p < 0.001), larger measured heart diameters by approximately 3 cm (p < 0.001), and larger thoracic diameters by approximately 2 cm (p < 0.001). CTRs on AP chest radiographs calculated with a cutoff of 0.50 had sensitivity of 86% and specificity of 32%. Sensitivity and specificity were 61% and 66% respectively when using a cutoff of 0.55, and 34% and 92% respectively when using a cutoff of 0.60. A CTR of 60% is more appropriate than 50-55% when evaluating an AP chest radiograph for cardiac chamber enlargement due to its much higher specificity.

Protein Engineered Triblock Polymers Composed of Two SADs: Enhanced Mechanical Properties and Binding Abilities.

Recombinant methods have been used to engineer artificial protein triblock polymers composed of two different self-assembling domains (SADs) bearing one elastin (E) flanked by two cartilage oligomeric matrix protein coiled-coil (C) domains to generate CEC. To understand how the two C domains improve small molecule recognition and the mechanical integrity of CEC, we have constructed CL44AECL44A, which bears an impaired CL44A domain that is unstructured as a negative control. The CEC triblock polymer demonstrates increased small molecule binding and ideal elastic behavior for hydrogel formation. The negative control CL44AECL44A does not exhibit binding to small molecule and is inelastic at lower temperatures, affirming the favorable role of C domain and its helical conformation. While both CEC and CL44AECL44A assemble into micelles, CEC is more densely packed with C domains on the surface enabling the development of networks leading to hydrogel formation. Such protein engineered triblock copolymers capable of forming robust hydrogels hold tremendous promise for biomedical applications in drug delivery and tissue engineering.

Impact of timing of ventriculoperitoneal shunt placement on outcome in posttraumatic hydrocephalus.

OBJECTIVE Posttraumatic hydrocephalus (PTH) is a frequent sequela of traumatic brain injury (TBI) and complication of related cranial surgery. The roles of PTH and the timing of cerebrospinal fluid (CSF) shunt placement in TBI outcome have not been well described. The goal of this study was to assess the impact of hydrocephalus and timing of ventriculoperitoneal (VP) shunt placement on outcome during inpatient rehabilitation after TBI. METHODS In this cohort study, all TBI patients admitted to Craig Hospital between 2009 and 2013 were evaluated for PTH, defined as ventriculomegaly, and hydrocephalus symptoms, delayed or deteriorating recovery, or elevated opening pressure on lumbar puncture. Extent of ventriculomegaly was quantified by the Evans index from CT scans. Outcome measures were emergence from and duration of posttraumatic amnesia (PTA) and functional status as assessed by means of the Functional Independence Measure (FIM). Findings in this group were compared to findings in a group of TBI patients without PTH (controls) who were admitted for inpatient rehabilitation during the same study period and met specific criteria for inclusion. RESULTS A total of 701 patients were admitted with TBI during the study period. Of these patients, 59 (8%) were diagnosed with PTH and were included in this study as the PTH group, and 204 who were admitted for rehabilitation and met the criteria for inclusion as controls constituted the comparison group (no-PTH group). PTH was associated with initial postinjury failure to follow commands, midline shift or cistern compression, subcortical contusion, and craniotomy or craniectomy. In multivariable analyses, independent predictors of longer PTA duration and lower FIM score at rehabilitation discharge were PTH, emergency department Glasgow Coma Scale motor score < 6, and longer time from injury to rehabilitation admission. PTH accounted for a 51-day increase in PTA duration and a 29-point reduction in discharge FIM score. In 40% of PTH patients with preshunt CT brain imaging analyzed, ventriculomegaly (Evans index > 0.3) was observed 3 or more days before VP shunt placement (median 10 days, range 3-102 days). Among PTH patients who received a VP shunt, earlier placement was associated with better outcome by all measures assessed and independently predicted better FIM total score and shorter PTA duration. CONCLUSIONS Posttraumatic hydrocephalus predicts worse outcome during inpatient rehabilitation, with poorer functional outcomes and longer duration of PTA. In shunt-treated PTH patients, earlier CSF shunting predicted improved recovery. These results suggest that clinical vigilance for PTH onset and additional studies on timing of CSF diversion are warranted.

Impact of phenylalanines outside the dimer interface on phosphotriesterase stability and function.

We explore the significance of phenylalanine outside of the phosphotriesterase (PTE) dimer interface through mutagenesis studies and computational modeling. Previous studies have demonstrated that the residue-specific incorporation of para-fluorophenylalanine (pFF) into PTE improves stability, suggesting the importance of phenylalanines in stabilization of the dimer. However, this comes at a cost of decreased solubility due to pFF incorporation into other parts of the protein. Motivated by this, eight single solvent-exposed phenylalanine mutants are evaluated viarosetta and good correspondence between experiments and these predictions is observed. Three residues, F304, F327, and F335, appear to be important for PTE activity and stability, even though they do not reside in the dimer interface region or active site. While the remaining mutants do not significantly affect structure or activity, one variant, F306L, reveals improved activity at ambient and elevated temperatures. These studies provide further insight into role of these residues on PTE function and stability.

HELMINTH INFECTIONS IN NORTHERN BOBWHITES (COLINUS VIRGINIANUS) FROM A LEGACY LANDSCAPE IN TEXAS, USA.

The Northern Bobwhite ( Colinus virginianus ) has declined across its range. The primary cause of this decline is thought to be habitat loss and fragmentation. However, there is speculation that factors such as parasites may play a role. South Texas recently was designated a Legacy Landscape of National Significance for Northern Bobwhite Conservation and is a region with some of the highest bobwhite densities in the US. Limited studies on bobwhite parasites have been conducted in this crucial landscape. We documented helminth parasites infecting bobwhites in South Texas, identified those that are known to be pathogenic to quail, documented pathologic responses to infection, and evaluated infections related to host intrinsic and extrinsic factors. We examined 209 bobwhites and found nine species of helminths including two known to cause tissue damage in bobwhites: Tetrameres pattersoni and Oxyspirura petrowi. The cecal nematode Aulonocephalus pennula was numerically dominant and had the greatest prevalence, intensity, and abundance. Prevalence and abundance of A. pennula were significantly greater in adult than juvenile bobwhites, whereas host sex was not an important factor. Prevalence of A. pennula was significantly greater during the 2012-13 hunting season than the 2013-14 season. The abundance of A. pennula also was significantly greater in bobwhites with greater mass within each age cohort. This research provides insight regarding the factors that influence helminth infections in bobwhites from South Texas and highlights the importance of broad-scale surveys when assessing helminth infections across large regions.

Nickel-catalyzed reductive arylation of activated alkynes with aryl iodides.

The direct, regioselective, and stereoselective arylation of activated alkynes with aryl iodides using a nickel catalyst and manganese reductant is described. The reaction conditions are mild (40 °C in MeOH, no acid or base) and an intermediate organomanganese reagent is unlikely. Functional groups tolerated include halides and pseudohalides, free and protected anilines, and a benzyl alcohol. Other activated alkynes including an amide and a ketone also reacted to form arylated products in good yields.

Reducing surgical site infections following craniotomy: examination of the use of topical vancomycin.

OBJECT: Although the use of topical vancomycin has been shown to be safe and effective for reducing postoperative infection rates in patients after spine surgery, its use in cranial wounds has not been studied systematically. The authors hypothesized that topical vancomycin, applied in powder form directly to the subgaleal space during closure, would reduce cranial wound infection rates. METHODS: A cohort of 150 consecutive patients who underwent craniotomy was studied retrospectively. Seventy-five patients received 1 g of vancomycin powder applied in the subgaleal space at the time of closure. This group was compared with 75 matched-control patients who were accrued over the same time interval and did not receive vancomycin. The primary outcome measure was the presence of surgical site infection within 3 months. Secondary outcome measures included tissue pH from a subgaleal drain and vancomycin levels from the subgaleal space and serum. RESULTS: Vancomycin was associated with significantly fewer surgical site infections (1 of 75) than was standard antibiotic prophylaxis alone (5 of 75; p < 0.05). Cultures were positive for typical skin flora species. As expected, local measured vancomycin concentrations peaked immediately after surgery (mean ± SD 499 ± 37 µg/ml) and gradually decreased over 12 hours. Vancomycin in the circulating serum remained undetectable. Subgaleal topical vancomycin was associated with a lower incidence of surgical site infections after craniotomy. The authors attribute this reduction in the infection rate to local vancomycin concentrations well above the minimum inhibitory concentration for antimicrobial efficacy. CONCLUSIONS: Topical vancomycin is safe and effective for reducing surgical site infections after craniotomy. These data support the need for a prospective randomized examination of topical vancomycin in the setting of cranial surgery.

Improved stability and half-life of fluorinated phosphotriesterase using Rosetta.

Recently we demonstrated that incorporating p-fluorophenylalanine (pFF) into phosphotriesterase dramatically improved folding, thereby leading to enhanced stability and function at elevated temperatures. To further improve the stability of the fluorinated enzyme, Rosetta was used to identify multiple potential stabilizing mutations. One such variant, pFF-F104A, exhibited enhanced activity at elevated temperature and maintained activity over many days in solution at room temperature.

The harm-made mind: observing victimization augments attribution of minds to vegetative patients, robots, and the dead.

People often think that something must have a mind to be part of a moral interaction. However, the present research suggests that minds do not create morality but that morality creates minds. In four experiments, we found that observing intentional harm to an unconscious entity--a vegetative patient, a robot, or a corpse--leads to augmented attribution of mind to that entity. A fifth experiment reconciled these results with extant research on dehumanization by showing that observing the victimization of conscious entities leads to reduced attribution of mind to those entities. Taken together, these experiments suggest that the effects of victimization vary according to victims' preexisting mental status and that people often make an intuitive cognitive error when unconscious entities are placed in harm's way. People assume that if apparent moral harm occurs, then there must be someone there to experience that harm-a harm-made mind. These findings have implications for political policies concerning right-to-life issues.