Redescription of Flexophora ophidii Prost & Euzet, 1962 (Monogenea: Diclidophoridae) from Ophidion barbatum (Ophidiidae) off the Algerian coast,Mediterranean Sea

Systematic Parasitology - The diclidophorid Flexophora ophidii Prost & Euzet, 1962, the type- and only species of the genus Flexophora Prost & Euzet, 1962, has never been...     

Soil inoculation of lodgepole pine seedlings alters root-associated fungal communities but does not improve seedling performance in beetle-killed pine stands

Extensive tree mortality in forests can change the community composition of soil fungi altering seedling establishment, a process critical to forest restoration. Disturbances that result in the loss of ectomycorrhizal fungi, in particular, may impede the establishment of tree species reliant on these symbionts for their survival. Inoculation of seedlings with soil from intact forests may improve the establishment of seedlings in such disturbances but the method has rarely been tested in the field. Here, we assess whether soil inoculation improves lodgepole pine (Pinus contorta var. latifolia) seedling performance in conspecific stands with high levels of tree mortality caused by a mountain pine beetle (Dendroctonus ponderosae) outbreak and whether underlying soil type modifies inoculation effects. We first inoculated seedlings in a growth chamber with small amounts of soils (5% volume) originating from either intact (<10%) or “beetle-killed” (>70% pine basal area killed) conspecific stands or added no soil inoculum and, after 4 months, transplanted them into 15 beetle-killed stands. After two growing seasons, root-associated fungal communities of seedlings receiving inoculum from intact stands differed in composition from those receiving inoculum from beetle-killed stands or no inoculum. However, inoculation had no effect on seedling survival, height, or biomass. Site properties, including soil texture and the resident fungal community composition, overwhelmed the effect of soil inoculation on seedling performance. Seedling survival and shoot mass was higher in sandy than loamy soils. Restoration to improve seedling performance in beetle-killed stands should consider stand-level treatments as soil inoculation at the level evaluated was ineffective.     

Ocular disease in patients with ANCA-positive vasculitis

Anti-neutrophil cytoplasmic antibody (ANCA)-positive vasculitis—the term recently applied to Wegener's granulomatosis—is a rare multi-system inflammation characterized by necrotizing granulomas and vasculitis. We investigated the ocular manifestations of this disease in a group of patients drawn from five inflammatory eye disease clinics across the United States. Of 8,562 persons with ocular inflammation, 59 individuals were diagnosed with ANCA-positive vasculitis; 35 males and 21 females, aged 16 to 96 years, were included in this study. Ocular diagnoses were scleritis (75.0%), uveitis (17.9%), and other ocular inflammatory conditions (33.9%) including peripheral ulcerative keratitis and orbital pseudotumor. Mean duration of ocular disease was 4.6 years. Oral corticosteroids and other systemic immunosuppressive agents were used by 85.7% and 78.5% of patients, respectively. Over time, patients with ANCA-positive vasculitis experienced 2.75-fold higher mortality than other patients with inflammatory eye disease.     

Initiating dialogue between scientists and managers of biological invasions

We describe an initiative to improve the flow of information between researchers and managers as part of two international scientific symposia on biological invasions held in South Africa in 2008 and 2009. Formal workshops and information sessions for land managers were run during the symposia. At the end of each symposium, the managers ran dedicated question-and-answer sessions on the research they felt was needed to improve their work. We discuss the potential of such interventions to increase interaction and awareness between researchers and managers of biological invasions. The symposia certainly provided the managers with opportunities to think about broader issues and develop contacts, but problems with terminology use and the lack of solutions specific to their context tempered the value of their experience. Conversely, researchers at times under-estimated the managers perceived relevance of their presentations to management. The structured and facilitated attendance of managers of invasive plants at international conferences on invasion biology is one mechanism for at least narrowing “the gap” between science and management.     

Caloric restriction maintains OX40 agonist-mediated tumor immunity and CD4 T cell priming during aging

Immune responses wane during aging, posing challenges to the potential effectiveness of cancer immunotherapies. We previously demonstrated that in the context of a promising immunotherapeutic, OX40 agonist (αOX40), older animals exhibited impaired anti-tumor immune responses and diminished CD4 T cell effector differentiation. In this study, we hypothesized that tumor immune responses could be maintained during aging through caloric restriction (CR) or dietary supplementation with resveratrol (RES), a CR mimetic. Mice were placed on either a calorically restricted diet or a RES-formulated diet starting between 4 and 6 months of age and continued until mice reached 12 months of age. Tumor immune responses were assessed after challenging with either sarcoma or breast tumor cells followed by αOX40 treatment. Our results show that CR, but not RES, maintained OX40-mediated anti-tumor immunity. In addition, CR fully sustained antigen-specific CD4 T cell priming in aged hosts (12 months old), whereas tumor-specific CD8 T cell priming was not fully maintained compared to young reference animals (2 months old). Thus, CR appears to maintain immunological fitness of the CD4 T cell priming environment during aging, which is critical for optimal OX40-mediated responses.     

Frost-Associated Defoliation in Populus tremuloides Causes Repeated Growth Reductions Over 185 years

Ecosystems - Climate change is causing a shift to earlier spring budburst in deciduous temperate trees, which may predispose them to greater risk of damage from growing season frosts. Populus...     

Physiological stage drives fungal community dynamics and diversity in Leptospermum scoparium (mānuka) flowers

Flowers are an important niche for microbes, and microbes in turn influence plant fitness. As flower morphology and biology change rapidly over time, dynamic niches for microbes are formed and lost. Floral physiology at each life stage can therefore influence arrival, persistence and loss of microbial species; however, this remains little understood despite its potential consequences for host reproductive success. Through internal transcribed spacer 1 (ITS1) community profiling, we characterized the effect of transitioning through five floral stages of mānuka (Leptospermum scoparium), from immature bud to spent flower, and subsequent allocation to seed, on the flower-inhabiting fungal community. We found nectar-consuming yeasts from Aureobasidium and Vishniacozyma genera and functionally diverse filamentous fungi from the Cladosporium genus dominated the anthosphere. The candidate core microbiota persisted across this dynamic niche despite high microbial turnover, as observed in shifts in community composition and diversity as flowers matured and senesced. The results demonstrated that floral stages are strong drivers of anthosphere fungal community assembly and dynamics. This study represents the first detailed exploration of fungi through floral development, building on fundamental knowledge in microbial ecology of healthy flowers.     

The aflagellate spermatozoon of Diplozoon (Platyhelminthes: Monogenea: Polyopisthocotylea): a demonstrative case of relationship between sperm ultrastructure and biology of reproduction

Diplozoon is known to display an exceptional biology of reproduction: the hermaphroditic adults are permanently fused together and their genital ducts communicate. In contrast to all other polyopisthocotylean monogeneans in which the spermatozoa show an homogeneous biflagellate structure, the spermatozoon of Diplozoon is aflagellate. It is filiform, and composed of a cytoplasmic region and a nuclear region. The cytoplasmic region exhibits mitochondria, a well-developed smooth endoplasmic reticulum, and up to 450 longitudinal singlet microtubules. The microtubules show links between them; seen in cross section, they are arranged as rows or polygons. The spermatozoon nuclear region contains the nucleus surrounded by cortical longitudinal microtubules. The spermiogenesis shows no zone of differentiation, a typical structure found in all other parasitic Platyhelminthes. Diplozoon is the first case of aflagellate spermatozoon found in the parasitic Platyhelminthes. The atypical sperm structure is not linked with phylogeny, but is well correlated with the atypical biology of reproduction.     

Habitat use and movements of plains zebra (Equus burchelli) in response to predation danger from lions

Prey species must adapt their behavior to avoid predation. Asa key prey item for lions (Panthera leo), plains zebras (Equusburchelli) were expected to respond to immediate threats posedby lions in their area. In addition, zebras were predicted toexhibit behavior tuned to reduce the potential for encounterswith lions, by modifying their movement patterns in the timesof day and habitats of greatest lion danger. We studied a populationof approximately 600 plains zebra living in Ol Pejeta Conservancy,Kenya. We found that zebra abundance on or near a grasslandpatch was lower if lions had also been observed on that patchduring the same day. Predation danger was highest in grasslandhabitat during the night, when lions were more active. Zebrasightings and global positioning system radio collar data indicatedthat zebras also reduced their use of grassland at night, insteadusing more woodland habitat. Zebras moved faster and took sharperturns in grassland at night. It is hypothesized that these moreerratic movements assist zebras in avoiding detection or captureby lions.