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This report describes a 49-year-old male construction worker who acquired a Bacillus anthracis infection after working on a sheep farm. He experienced a severe respiratory infection, septic shock, and hemorrhagic meningoencephalitis with severe intracranial hypertension. After several weeks with multiple organ dysfunction syndrome, he responded favorably to antibiotic treatment. Three weeks into his hospitalization, an intracranial hemorrhage and cerebral edema led to an abrupt deterioration in his neurological status. A single dose of raxibacumab was added to his antimicrobial regimen on hospital day 27. His overall status, both clinical and radiographic, improved within a few days. He was discharged 2 months after admission and appears to have fully recovered.

The objective of this work was to assess whether the injury mechanisms are responsible for histological arterial lesions. This prospective single-center study included adults with wrist or hand arterial injury. Arterial resection of at least 2 mm from the proximal and distal stumps was performed before the arterial anastomosis. Histological analysis of the arterial stumps was performed. An ultrasound was performed 1 month postoperatively to check arterial patency. A clinical and functional evaluation was done at 1 month postoperative, then every 3 months. From 2018 to 2020, 46 patients were included with a maximum follow-up of 13 months. There were 35 cuts, 2 crush injuries, 8 amputation and 1 blast injury. Macroscopically, 37% of the margins were considered damaged. Histological analysis showed significant damage in 59% of the sections (27 out of 46 patients) with 50% for crush injury, 55% for cuts by mechanical tool, 62% for cuts by power tool, 62% for amputations and 100% for blasts. The failure rate was 9%: 2 replantations and 2 asymptomatic thromboses diagnosed by ultrasound. Postoperative pain on VAS was 1.75/10, range of motion was 87%, Quick DASH was 8%, SF36 PCS was 69% and SF36 MCS was 70%. Factors influencing the success or failure of anastomosis were the mechanism of injury (p = 0.02), associated nerve damage (p = 0.014) and length of proximal arterial cut (p = 0.046). Histological arterial lesions seem to correlate with the injury mechanism. Cuts caused by glass or crush injuries do not seem to require arterial resections of more than 2 mm. A continuation of the study with a larger number of subjects may generate statistically significant results.

Bacillus anthracis has traditionally been considered the etiologic agent of anthrax. However, anthrax-like illness has been documented in welders and other metal workers infected with Bacillus cereus group spp. harboring pXO1 virulence genes that produce anthrax toxins. We present 2 recent cases of severe pneumonia in welders with B. cereus group infections and discuss potential risk factors for infection and treatment options, including antitoxin.

Distribution of Earth's biomes is structured by the match between climate and plant traits, which in turn shape associated communities and ecosystem processes and services. However, that climate-trait match can be disrupted by historical events, with lasting ecosystem impacts. As Earth's environment changes faster than at any time in human history, critical questions are whether and how organismal traits and ecosystems can adjust to altered conditions. We quantified the relative importance of current environmental forcing versus evolutionary history in shaping the growth form (stature and biomass) and associated community of eelgrass (Zostera marina), a widespread foundation plant of marine ecosystems along Northern Hemisphere coastlines, which experienced major shifts in distribution and genetic composition during the Pleistocene. We found that eelgrass stature and biomass retain a legacy of the Pleistocene colonization of the Atlantic from the ancestral Pacific range and of more recent within-basin bottlenecks and genetic differentiation. This evolutionary legacy in turn influences the biomass of associated algae and invertebrates that fuel coastal food webs, with effects comparable to or stronger than effects of current environmental forcing. Such historical lags in phenotypic acclimatization may constrain ecosystem adjustments to rapid anthropogenic climate change, thus altering predictions about the future functioning of ecosystems., This work was supported by the US NSF (OCE-1031061, OCE-1336206, OCE0-1336741, OCE-1336905) and the Smithsonian Institution. F.T. was supported by José Castillejo Award CAS14/00177. A.H.E. was supported by the FCT (Foundation for Science and Technology) through Project UIDB/04326/2020 and Contract CEECINST/00114/2018. This is Contribution 106 from the Smithsonian’s MarineGEO and Tennenbaum Marine Observatories Network and Contribution 4105 of the Virginia Institute of Marine Science, College of William & Mary.

Inhalation anthrax has three clinical stages: early-prodromal, intermediate-progressive and late- fulminant. The toxins produced during infection exert pathologic effects leading to death, but they have not been comprehensively characterized throughout the course of infection. Mass spectrometry methods for anthrax toxins, total-protective antigen (PA), total-lethal factor (LF), total-edema factor (EF), and toxin complexes, lethal toxin and edema toxin were used to characterize the stages of inhalation anthrax in 23 cynomolgus macaques. The target aerosol dose was 200 LD50B. anthracis Ames spores. 22 animals died during the study. Different patterns of toxemia and bacteremia were observed in 11 animals with the shortest survival times (fast progression), the 11 animals with longer survival (slow progression), and the one survivor. Toxemia and bacteremia were predominantly triphasic with an early rise (phase-1), a plateau/decline (phase-2), and a final rapid rise (phase-3). The patterns were consistent for all toxins. The end-of-phase-1 LF was higher in fast progression [median(lower quartile– upper quartile)] of [195(57.4–326)-ng/mL], than in slow progression [23.8(15.6–26.3)-ng/mL] (p=0.0001), or the surviving animal [11.1-ng/mL]. End-of-phase-1 EF was also higher in fast [22.2(2.7– 42.8)-ng/mL] than slow progression [0.17(0.064–0.066)-ng/mL] (p=0.0005), or the surviving animal [0.040-ng/mL]. Animals with slow progression and lower end-of-phase-1 toxemia, had an extended plateau/decline (≥24-hours), with low variability of PA, LF, and LTx across all animals. Its characterization revealed an upper threshold; a limit for exiting phase-2 and entering the critical phase-3, 342-ng/mL (PA), 35.8-ng/mL (LF), and 1.10-ng/mL (EF). The thresholds were exceeded early in animals with fast progression (38.3±7.4-hours) and later in slow progression (78.7±14.1-hours). Once the threshold was passed toxin levels rose rapidly, differences in toxemia were reduced, and the duration to terminal was rapid and similar; 21.0±7.3-hours for fast and 20.4±7.3-hours for slow. This first comprehensive evaluation of anthrax toxins defined all stages, providing insights into disease progression.Author SummaryThe comprehensive analysis of all major anthrax toxins and bacteremia in a non-human primate model of inhalation anthrax revealed a triphasic kinetics of toxemia that aligns with the three clinical stages, early-prodromal, intermediate-progressive and late-fulminant. End of phase-1 toxin levels may predict the subsequent speed of progression. Phase-2 toxemia helped define critical thresholds representing the entry to phase-3. Exceeding these thresholds was associated with a short remaining survival time (about 21 hours). This first comprehensive characterization of toxemia provides knowledge and guidance for better management of anthrax.

PurposeAchieving professional competence requires a wide-ranging approach of preparation through education. Instructional approaches to advance proper training of future clinicians should contain an array of academic and field experiences that translate into clinical competency; this includes immersion in varied sceneries and exposure to different contexts. For that end, it is crucial to embrace the most current societal paradigms.ConclusionsThis tutorial describes activities devised to promote higher education pursuits through intercontinental partnership, using recent and ongoing cooperation between two universities in different countries as a backdrop for reflections. The ultimate goal of this tutorial is to summarize collaborative efforts in order to promote similar pursuits. Activities devised to foster international scholastic partnerships aimed at increased professional competence are described.

Protective legislation and management have led to an increase in California’s sea otter Enhydra lutris nereis population. While sea otter recovery has been linked to ecosystem benefits, sea otter predation may negatively affect commercially valuable species. Understanding the potential influence of sea otters is of particular importance as their range expands into estuaries that function as nurseries for commercially valuable species like Dungeness crab Metacarcinus magister. We consider how sea otter predation has affected the abundance and size of juvenile Dungeness crab in Elkhorn Slough, California, USA, and analyzed cancrid crab abundance and size across 4 California estuaries with and without sea otters to understand how biotic and abiotic factors contribute to observed variation in crab size and abundance. We compared trends in southern sea otters relative to Dungeness crab landings in California to assess whether increasing sea otter abundance have negatively impacted landings. In Elkhorn Slough, juvenile Dungeness crab abundance and size have declined since 2012, coinciding with sea otter population growth. However, the impact of sea otters on juvenile Dungeness crab size was habitat-specific and only significant in unvegetated habitat. Across estuaries, we found that cancrid crab abundance and size were negatively associated with sea otter presence. While abiotic factors varied among estuaries, these factors explained little of the observed variation in crab abundance or size. Although we found evidence that sea otters can have localized effects on cancrid crab populations within estuaries, we found no evidence that southern sea otters, at recent population sizes, have negatively impacted Dungeness crab landings in California from 2000-2014.

Background Inhalational anthrax is rare and clinical experience limited. Expert guidelines recommend treatment with combination antibiotics including protein synthesis-inhibitors to decrease toxin production and increase survival, although evidence is lacking. Methods Rhesus macaques exposed to an aerosol of Bacillus anthracis spores were treated with ciprofloxacin, clindamycin, or ciprofloxacin + clindamycin after becoming bacteremic. Circulating anthrax lethal factor and protective antigen were quantitated pretreatment and 1.5 and 12 hours after beginning antibiotics. Results In the clindamycin group, 8 of 11 (73%) survived demonstrating its efficacy for the first time in inhalational anthrax, compared to 9 of 9 (100%) with ciprofloxacin, and 8 of 11 (73%) with ciprofloxacin + clindamycin. These differences were not statistically significant. There were no significant differences between groups in lethal factor or protective antigen levels from pretreatment to 12 hours after starting antibiotics. Animals that died after clindamycin had a greater incidence of meningitis compared to those given ciprofloxacin or ciprofloxacin + clindamycin, but numbers of animals were very low and no definitive conclusion could be reached. Conclusion Treatment of inhalational anthrax with clindamycin was as effective as ciprofloxacin in the nonhuman primate. Addition of clindamycin to ciprofloxacin did not enhance reduction of circulating toxin levels.

The poly-γ-glutamic acid (PGA) capsule produced by Bacillus anthracis is composed entirely of d-isomer glutamic acid, whereas nonpathogenic Bacillus species produce mixed d-, l-isomer PGAs. To determine if B. anthracis PGA confers a pathogenic advantage over other PGAs, we compared the responses of human innate immune cells to B. anthracis PGA and PGAs from nonpathogenic B. subtilis subsp. chungkookjang and B. licheniformis. Monocytes and immature dendritic cells (iDCs) responded differentially to the PGAs, with B. anthracis PGA being least stimulatory and B. licheniformis PGA most stimulatory. All three elicited IL-8 and IL-6 from monocytes, but B. subtilis PGA also elicited IL-10 and TNF-α, whereas B. licheniformis PGA elicited all those plus IL-1β. Similarly, all three PGAs elicited IL-8 from iDCs, but B. subtilis PGA also elicited IL-6, and B. licheniformis PGA elicited those plus IL-12p70, IL-10, IL-1β, and TNF-α. Only B. licheniformis PGA induced dendritic cell maturation. TLR assays also yielded differential results. B. subtilis PGA and B. licheniformis PGA both elicited more TLR2 signal than B. anthracis PGA, but only responses to B. subtilis PGA were affected by a TLR6 neutralizing Ab. B. licheniformis PGA elicited more TLR4 signal than B. anthracis PGA, whereas B. subtilis PGA elicited none. B. anthracis PGA persisted longer in high m.w. form in monocyte and iDC cultures than the other PGAs. Reducing the m.w. of B. anthracis PGA reduced monocytes’ cytokine responses. We conclude that B. anthracis PGA is recognized less effectively by innate immune cells than PGAs from nonpathogenic Bacillus species, resulting in failure to induce a robust host response, which may contribute to anthrax pathogenesis.

While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass (Zostera marina) spanning 30° of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change., This research was funded by National Science Foundation grants to J.E.D., J.J.S. and K.A.H. (NSF-OCE 1336206, OCE 1336905, and OCE 1336741). C.B. was funded by the Åbo Akademi University Foundation.

The global decline of marine foundation species (kelp forests, mangroves, salt marshes, and seagrasses) has contributed to the degradation of the coastal zone and threatens the loss of critical ecosystem services and functions. Restoration of marine foundation species has had variable success, especially for seagrasses, where a majority of restoration efforts have failed. While most seagrass restorations track structural attributes over time, rarely do restorations assess the suite of ecological functions that may be affected by restoration. Here we report on the results of two small-scale experimental seagrass restoration efforts in a central California estuary where we transplanted 117 0.25-m2 plots (2,340 shoots) of the seagrass species Zostera marina. We quantified restoration success relative to persistent reference beds, and in comparison to unrestored, unvegetated areas. Within three years, our restored plots expanded ˜8,500%, from a total initial area of 29 to 2,513 m2 . The restored beds rapidly began to resemble the reference beds in (1) seagrass structural attributes (canopy height, shoot density, biomass), (2) ecological functions (macrofaunal species richness and abundance, epifaunal species richness, nursery function), and (3) biogeochemical functions (modulation of water quality). We also developed a multifunctionality index to assess cumulative functional performance, which revealed restored plots are intermediate between reference and unvegetated habitats, illustrating how rapidly multiple functions recovered over a short time period. Our comprehensive study is one of few published studies to quantify how seagrass restoration can enhance both biological and biogeochemical functions. Our study serves as a model for quantifying ecosystem services associated with the restoration of a foundation species and demonstrates the potential for rapid functional recovery that can be achieved through targeted restoration of fast-growing foundation species under suitable conditions.

In addition to its high biodiversity, the California Floristic Province contains over 1600 rare taxa, including many endemics restricted to specific soil types and habitats. In the highly urbanized San Francisco Estuary, these narrow endemics face additional limitations from habitat destruction and modification, prompting an interest in their conservation and management. One such taxon, the Federally listed Cirsium hydrophilum (Greene) Jeps. var. hydrophilum (Suisun thistle), is restricted to two or three populations, and may face limitations beyond past habitat loss. In this study, we investigated life history limitations that may contribute to rarity in C. hydrophilum var. hydrophilum. We documented low seed set, high seed predation by beetle larvae, low localized wind dispersal of seeds, and possible inbreeding in smaller patches. Because seeds did not have a stringent germination requirement in the lab, however, restoration or introduction of new populations from seed is possible. Using seeds from larger source populations could increase success of reseeding, as could adding seeds to augment potentially low genetic diversity in existing smaller subpopulations. Further study is needed to understand the ecology of seed predators, the relative importance of seed set and seed germination in the field, and to confirm our potential finding of reduced genetic diversity and inbreeding. Though the causes and consequences of rarity may differ for each species, this study explores several research directions that could be productive for understanding other California endemic Cirsium and rare wetland endemics.

Less than 5% of US veterinary school graduates go on to practice predominantly food animal medicine, contributing to a serious shortage of veterinarians practicing in rural areas. Exposing students to clinical and farm experiences while in veterinary school is an effective way to recruit them to various types of veterinary careers. Students at the University of Minnesota College of Veterinary Medicine (UMN CVM) were not always aware of food animal course options within the curriculum. Additionally, food animal faculty had noted that while face-to-face mentoring was the most effective way to help students select courses, it was too dependent upon faculty availability and students’ comfort level in reaching out for advice. Consequently, it was decided to develop an online catalog of course options focusing on food animal topics. This course catalog, called the Food Animal Curriculum Roadmap, was designed as an interactive roadmap similar to a map of subway lines, where each line represents a species of interest (beef, dairy, small ruminant, swine, and poultry) and each station is a course. The roadmap was made available to all students at the college. A user survey showed that 96% of the respondents ( n = 30) indicated that they had a better understanding of course offerings after using the Food Animal Curriculum Roadmap.

Inhalation of Bacillus anthracis spores can cause a rapidly progressing fatal infection. B. anthracis secretes three protein toxins: lethal factor (LF), edema factor (EF), and protective antigen (PA). EF and LF may circulate as free or PA-bound forms. Both free EF (EF) and PA-bound-EF (ETx) have adenylyl cyclase activity converting ATP to cAMP. We developed an adenylyl cyclase activity-based method for detecting and quantifying total EF (EF+ETx) in plasma. The three-step method includes magnetic immunocapture with monoclonal antibodies, reaction with ATP generating cAMP, and quantification of cAMP by isotope-dilution HPLC-MS/MS. Total EF was quantified from 5PL regression of cAMP vs ETx concentration. The detection limit was 20 fg/mL (225 zeptomoles/mL for the 89 kDa protein). Relative standard deviations for controls with 0.3, 6.0, and 90 pg/mL were 11.7–16.6% with 91.2–99.5% accuracy. The method demonstrated 100% specificity in 238 human serum/plasma samples collected from unexposed healthy individuals, and 100% sensitivity in samples from 3 human and 5 rhesus macaques with inhalation anthrax. Analysis of EF in the rhesus macaques showed that it was detected earlier post-exposure than B. anthracis by culture and PCR. Similar to LF, the kinetics of EF over the course of infection were triphasic, with an initial rise (phase-1), decline (phase-2), and final rapid rise (phase-3). EF levels were ~ 2–4 orders of magnitude lower than LF during phase-1 and phase-2 and only ~ 6-fold lower at death/euthanasia. Analysis of EF improves early diagnosis and adds to our understanding of anthrax toxemia throughout infection. The LF/EF ratio may also indicate the stage of infection and need for advanced treatments.