Molecular data confirm the validity of the Portuguese blenny (Parablennius ruber, Valenciennes, 1836) and its presence in Western Europe

DNA sequence analysis confirms the distinction between Parablennius ruber and Parablennius gattorugine , simultaneously validating the presence of the former species in Western Europe where it has been reported for >150 years. A possible scenario involving speciation of P. ruber at the Azores and subsequent transport of larvae to Europe, a process that may be still occurring nowadays, could explain this pattern of occurrence.     

New Insights from the Oyster Crassostrea rhizophorae on Bivalve Circulating Hemocytes

Hemocytes are the first line of defense of the immune system in invertebrates, but despite their important role and enormous potential for the study of gene-environment relationships, research has been impeded by a lack of consensus on their classification. Here we used flow cytometry combined with histological procedures, histochemical reactions and transmission electron microscopy to characterize the hemocytes from the oyster Crassostrea rhizophorae. Transmission electron microscopy revealed remarkable morphological characteristics, such as the presence of membranous cisternae in all mature cells, regardless of size and granulation. Some granular cells contained many cytoplasmic granules that communicated with each other through a network of channels, a feature never previously described for hemocytes. The positive reactions for esterase and acid phosphatase also indicated the presence of mature cells of all sizes and granule contents. Flow cytometry revealed a clear separation in complexity between agranular and granular populations, which could not be differentiated by size, with cells ranging from 2.5 to 25 µm. Based on this evidence we suggest that, at least in C. rhizophorae, the different subpopulations of hemocytes may in reality be different stages of one type of cell, which accumulates granules and loses complexity (with no reduction in size) as it degranulates in the event of an environmental challenge.     

Habitat-related differences in recruitment and survival of early recruits of the invasive <Emphasis Type="Italic">Sargassum muticum</Emphasis> (Phaeophyta,Sargassaceae) in northern Portugal

Habitat-related differences in recruitment and early survival of the invasive seaweed Sargassum muticum were investigated in relation to the lunar phase (gamete release trigger) and meso-grazing between mid-intertidal and low-intertidal pools in northern Portugal. In situ experiments were performed to determine recruitment and to test the effect of intertidal level (mid-intertidal and low-intertidal pools), grazing (no cage, cage and open cage), and lunar phase (full, new and each quarter moon) on recruit survival during reproductive seasons in two consecutive years. Our results show clearly that recruitment and survival were higher in the mid-intertidal than in low-intertidal environment in both study periods. Caging treatments affected recruit survival in both environments, however, differences in patterns suggesting differences in grazing pressure due to differences in grazer density and/or the assemblages. It therefore seems that grazing on early recruits of this invader might contribute to the resistance to proliferation. Mid-intertidal pools constitute a more favourable environment for recruits of S. muticum than the low-intertidal, which may explain the mainly mid-intertidal distribution of the species in Portugal.     

Molecular Features Contributing to Virus-Independent Intracellular Localization and Dynamic Behavior of the Herpesvirus Transport Protein US9

Reaching the right destination is of vital importance for molecules, proteins, organelles, and cargoes. Thus, intracellular traffic is continuously controlled and regulated by several proteins taking part in the process. Viruses exploit this machinery, and viral proteins regulating intracellular transport have been identified as they represent valuable tools to understand and possibly direct molecules targeting and delivery. Deciphering the molecular features of viral proteins contributing to (or determining) this dynamic phenotype can eventually lead to a virus-independent approach to control cellular transport and delivery. From this virus-independent perspective we looked at U_S9, a virion component of Herpes Simplex Virus involved in anterograde transport of the virus inside neurons of the infected host. As the natural cargo of U_S9-related vesicles is the virus (or its parts), defining its autonomous, virus-independent role in vesicles transport represents a prerequisite to make U_S9 a valuable molecular tool to study and possibly direct cellular transport. To assess the extent of this autonomous role in vesicles transport, we analyzed U_S9 behavior in the absence of viral infection. Based on our studies, Us9 behavior appears similar in different cell types; however, as expected, the data we obtained in neurons best represent the virus-independent properties of U_S9. In these primary cells, transfected U_S9 mostly recapitulates the behavior of U_S9 expressed from the viral genome. Additionally, ablation of two major phosphorylation sites (i.e. Y₃₂Y₃₃ and S₃₄ES₃₆) have no effect on protein incorporation on vesicles and on its localization on both proximal and distal regions of the cells. These results support the idea that, while U_S9 post-translational modification may be important to regulate cargo loading and, consequently, virion export and delivery, no additional viral functions are required for U_S9 role in intracellular transport.     

Cadmium toxicity affects photosynthesis and plant growth at different levels

In this article we discuss and update some of the effects of Cd toxicity on the photosynthetic apparatus in a model crop Lactuca sativa. Seeds of L. sativa were germinated in solutions with 0, 1, 10 and 50 μM of Cd(NO₃)₂ and then transferred to a hydroponic culture medium. After 28 days, the effects of Cd on the photosynthetic apparatus of lettuce were analysed. Exposure of lettuce to 1 μM Cd(NO₃)₂ affected already plant growth (dry biomass), but, did not induce serious damages in the photosynthetic apparatus. However, increasing concentrations of this metal to 10 and 50 μM promoted a strong reduction of the maximum photochemical efficiency of PSII and an impairment of net CO₂ assimilation rate, putatively due to Rubisco activity decrease. This ultimately results in a strong inhibition of plant growth. Nutrient uptake and carbohydrate assimilation were also severely affected by Cd.     

Liquid vs Solid Culture Medium to Evaluate Proportion and Time to Change in Management of Suspects of Tuberculosis—A Pragmatic Randomized Trial in Secondary and Tertiary Health Care Units in Brazil

Background

The use of liquid medium (MGIT960) for tuberculosis (TB) diagnosis was recommended by WHO in 2007. However, there has been no evaluation of its effectiveness on clinically important outcomes.

Methods and Findings

A pragmatic trial was carried out in a tertiary hospital and a secondary health care unit in Rio de Janeiro City, Brazil. Participants were 16 years or older, suspected of having TB. They were excluded if only cerebral spinal fluid or blood specimens were available for analysis. MGIT960 technique was compared with the Lowenstein-Jensen (LJ) method for laboratory diagnosis of active TB. Primary outcome was the proportion of patients who had their initial medical management changed within 2 months after randomisation. Secondary outcomes were: mean time for changing the procedure, patient satisfaction with the overall treatment and adverse events. Data were analysed by intention-to-treat. Between April 2008 and September 2011, 693 patients were enrolled (348 to MGIT, 345 to LJ). Smear and culture results were positive for 10% and 15.7% of participants, respectively. Patients in the MGIT arm had their initial medical management changed more frequently than those in the LJ group (10.1% MGIT vs 3.8% LJ, RR 2.67 95% CI 1.44–.96, p = 0.002, NNT 16, 95% CI 10–39). Mean time for changing the initial procedure was greater in LJ group at both sites: 20.0 and 29.6 days in MGIT group and 52.2 and 64.3 in LJ group (MD 33.5, 95% CI 30.6–36.4, p = 0.0001). No other important differences were observed.

Conclusions

This study suggests that opting for the MGIT960 system for TB diagnosis provides a promising case management model for improving the quality of care and control of TB.

Trial Registration

Controlled-Trials.com ISRCTN79888843