The relative importance for plant invasiveness of trait means, and their plasticity and integration in a multivariate framework

? Functional traits, their plasticity and their integration in a phenotype have profound impacts on plant performance. We developed structural equation models (SEMs) to evaluate their relative contribution to promote invasiveness in plants along resource gradients. ? We compared 20 invasive-native phylogenetically and ecologically related pairs. SEMs included one morphological (root-to-shoot ratio (R/S)) and one physiological (photosynthesis nitrogen-use efficiency (PNUE)) trait, their plasticities in response to nutrient and light variation, and phenotypic integration among 31 traits. Additionally, these components were related to two fitness estimators, biomass and survival. ? The relative contributions of traits, plasticity and integration were similar in invasive and native species. Trait means were more important than plasticity and integration for fitness. Invasive species showed higher fitness than natives because: they had lower R/S and higher PNUE values across gradients; their higher PNUE plasticity positively influenced biomass and thus survival; and they offset more the cases where plasticity and integration had a negative direct effect on fitness. ? Our results suggest that invasiveness is promoted by higher values in the fitness hierarchy -- trait means are more important than trait plasticity, and plasticity is similar to integration -- rather than by a specific combination of the three components of the functional strategy.     

Effectiveness of a Pilot Partner Notification Program for New HIV Cases in Barcelona,Spain

Background

An estimated 30% of HIV cases in the European Union are not aware of their serological status. This study aimed to assess the effectiveness of a pilot HIV partner notification program.

Methods

HIV cases diagnosed between January 2012 and June 2013 at two healthcare settings in Barcelona were invited to participate in a prospective survey. We identified process and outcome measures to evaluate this partner notification program, including the number of partners identified per interviewed index case, the proportion of partners tested for HIV as a result of the partner notification, and the proportion of new HIV diagnoses among their sex or needle-sharing partners.

Results

Of the 125 index cases contacted, 108 (86.4%) agreed to provide information about partners. A total of 199 sexual partners were identified (1.8 partners per interviewed index case). HIV outcome was already known for 58 partners (70.7% were known to be HIV-positive), 141 partners were tested as result of partner notification, and 26 were newly diagnosed with HIV. The case-finding effectiveness of the program was 18.4%.

Conclusion

This pilot program provides evidence of the effectiveness of a partner notification program implemented in healthcare settings. This active partner notification program was feasible, acceptable to the user, and identified a high proportion of HIV-infected patients previously unaware of their status.     

Use of liquid nitrogen during storage in a cell and tissue bank: contamination risk and effect on the detectability of potential viral contaminants

Cryopreservation is widely used for banking cells and tissues intended for transplantation. Liquid nitrogen provides a very stable ultra-low temperature environment. Thus, it is used for longterm storage. Unlike the exhaustive microbiological monitoring of the environmental conditions during tissue processing, storage is not usually considered as a critical point of potential contamination risk in professional standards for cell and tissue banking. We have analysed the presence of microbial agents inside our nitrogen tanks. We have mainly detected environmental and water-borne bacteria and fungi. In addition, we have studied the effect of liquid nitrogen exposure on virus detectability. Only differences for hepatitis C virus RNA were observed. Measures for contamination risk reduction during storage must be mandatory in cell and tissue banking.     

Efficient colonization of the endophytes Herbaspirillum huttiense RCA24 and Enterobacter cloacae RCA25 influences the physiological parameters of Oryza sativa L. cv. Baldo rice

Several important bacterial characteristics, such as biological nitrogen fixation, phosphate solubilization, 1-aminocyclopropane-1-carboxylate deaminase activity and production of siderophores and phytohormones, can be assessed as plant growth promotion traits. Our aim was to evaluate the effects of nitrogen fixing and indole-3-acetic acid (IAA) producing endophytes in two Oryza sativa cultivars (Baldo and Vialone Nano). Three bacteria, Herbaspirillum huttiense RCA24, Enterobacter asburiae RCA23 and Staphylococcus sp. 377, producing different IAA levels, were tested for their ability to enhance nifH gene expression and nitrogenase activity in Enterobacter cloacae RCA25. Results showed that H. huttiense RCA24 performed best. Improvement in nitrogen fixation and changes in physiological parameters such as chlorophyll, nitrogen content and shoot dry weight were observed for plants co-inoculated with strains RCA25 and RCA24 in a 10:1 ratio. Based on confocal laser scanning microscopy analysis, strain RCA24 was the best colonizer of the root interior and the only IAA producer located in the same root niche occupied by RCA25 cells. This work shows that the choice of a bio-inoculum having the right composition is one of the key aspects to be considered for the inoculation of a specific host plant cultivar with microbial consortia.     

In vivo site-specific recombination using the beta-rec/six system

The prokaryotic beta serine recombinase (beta-rec) catalyzes site-specific recombination between two directly oriented six sites (93 bp) in mammalian cells, both in episomal and in chromosomally integrated substrates. The beta-rec/six exclusive intramolecular site-specific recombination (SSR) system has been proposed as a suitable approach when several independently controlled recombination events are needed in a single cell. Here we explored the use of the beta-rec/six system for selective induction of genome-targeted modifications. We generated and analyzed mouse transgenic lines (Tgbeta) expressing beta-rec under the control of the Lck promoter. beta-rec activity was demonstrated, and there was no evidence of alterations to thymic or peripheral T cell development. We developed two transgenic mouse lines harboring different target sequences (Tgrec and KOsix) and analyzed the effect of beta-rec expression on these animals. The results indicate that the beta-rec/six SSR system is functional for in vivo gene-targeting applications.     

Cytologic features of clear cell carcinoma of the female genital tract. Diagnostic value of the "raspberry body" in nonexfoliative cytologic specimens

OBJECTIVE: To evaluate the presence of basement membrane stromal material in fine needle aspiration (FNA) and scrape cytologic specimens from patients with clear cell carcinoma (CCC) of the female genital tract. STUDY DESIGN: The study group consisted of 6 patients with CCC (5 ovarian and 1 cervical). Four samples corresponded to FNA specimens and 3 to scrape material obtained during intraoperative consultation for ovarian tumors. FNA was performed on a pelvic recurrence and on liver, pulmonary and lymph node metastases. The 6 cases had a complete histopathologic study. RESULTS: In addition to large, clear cells, all cases showed basement membrane stromal material that assumed several forms. The most common was globular, hyaline structures, either naked or surrounded by neoplastic epithelial cells ("raspberry bodies"). Other fragments were larger, with several spherules and elongated prolongations. Scrape material showed stromal material resembling reduplicated basement membrane material. In Diff-Quik-stained smears (QCA, Tarragana, Spain) it showed metachromatic staining with a pink to purple color. Its recognition on Papanicolaou-stained smears was more difficult since it did not stain or was gray. CONCLUSION: Basement membrane stromal material and, more precisely, "raspberry bodies," are a characteristic cytologic feature of CCC of the female genital tract. The combination of clear, atypical cells and basement membrane stroma is highly specific to this neoplasm and can be observed not only in exfoliative specimens but also in FNA and scrape samples.     

Growth in elevated CO2 enhances temperature response of photosynthesis in wheat

The temperature dependence of C₃ photosynthesis may be altered by the growth environment. The effects of long-term growth in elevated CO₂ on photosynthesis temperature response have been investigated in wheat ( Triticum aestivum L.) grown in controlled chambers with 370 or 700 μmol mol⁻¹ CO₂ from sowing through to anthesis. Gas exchange was measured in flag leaves at ear emergence, and the parameters of a biochemical photosynthesis model were determined along with their temperature responses. Elevated CO₂ slightly decreased the CO₂ compensation point and increased the rate of respiration in the light and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) V_cmax, although the latter effect was reversed at 15°C. With elevated CO₂, J_max decreased in the 15–25°C temperature range and increased at 30 and 35°C. The temperature response (activation energy) of V_cmax and J_max increased with growth in elevated CO₂. CO₂ enrichment decreased the ribulose 1,5-bisphosphate (RuBP)-limited photosynthesis rates at lower temperatures and increased Rubisco- and RuBP-limited rates at higher temperatures. The results show that the photosynthesis temperature response is enhanced by growth in elevated CO₂. We conclude that if temperature acclimation and factors such as nutrients or water availability do not modify or negate this enhancement, the effects of future increases in air CO₂ on photosynthetic electron transport and Rubisco kinetics may improve the photosynthetic response of wheat to global warming.