Arbuscular Mycorrhizal Symbiosis with Arundo donax Decreases Root Respiration and Increases Both Photosynthesis and Plant Biomass Accumulation

The effect of arbuscular mycorrhiza (AM) symbiosis on plant growth is associated with the balance between costs and benefits. A feedback regulation loop has been described in which the higher carbohydrate cost to plants for AM symbiosis is compensated by increases in their photosynthetic rates. Nevertheless, plant carbon balance depends both on photosynthetic carbon uptake and respiratory carbon consumption. The hypothesis behind this research was that the role of respiration in plant growth under AM symbiosis may be as important as that of photosynthesis. This hypothesis was tested in Arundo donax L. plantlets inoculated with Rhizophagus irregularis and Funneliformis mosseae. We tested the effects of AM inoculation on both photosynthetic capacity and in vivo leaf and root respiration. Additionally, analyses of the primary metabolism and ion content were performed in both leaves and roots. AM inoculation increased photosynthesis through increased CO₂ diffusion and electron transport in the chloroplast. Moreover, respiration decreased only in AM roots via the cytochrome oxidase pathway (COP) as measured by the oxygen isotope technique. This decline in the COP can be related to the reduced respiratory metabolism and substrates (sugars and tricarboxylic acid cycle intermediates) observed in roots.     

Intravenous thrombolysis for acute ischemic stroke--our experiences

Intravenous (i.v.) thrombolysis with recombinant tissue plasminogen activator (rt-PA) is the only available pharmacological therapy to improve the outcome of acute ischemic stroke. We compared 71 patients presenting with ischaemic stroke and given intravenous rt-PA (0.9 mg/kg total dose) within 3 h with 71 patients who present to the hospital more than 3 hours after stroke symptom onset. The primary endpoint was the modified Rankin scale (mRS) at 90 days, dichotomised for favourable and unfavourable (score 2-6). Outcome measures were symptomatic intracerebral haemorrhage within 36 h (haemorrhage associated with National Institutes of Health Stroke Scale [NIHSS] > or = 4 points deterioration), and mortality at 3 months. More patients had favourable outcome with the rt-PA-treated group than with the control group (64.79% vs. 22.54%; p = 0.0001). The greater proportion of patients left with minimal or no deficit 90 days after rt-PA treatment, as compared with the control group. In the treated group symptomatic intracranial hemorrhage occurred in 1 patient who recovered to a level of functional independence, and asymptomatic intracranial hemorrhage was observed in 2 patients. Our experience of an acute stroke thrombolysis service shows that we are able to provide this treatment safely and in accordance with established treatment guidelines. We recommend thrombolytic treatment in acute ischemic stroke for selected population.     

Rapid production of functionalized recombinant proteins: marrying ligation independent cloning and in vitro protein ligation

Functional genomics and proteomics have been very active fields since the sequencing of several genomes was completed. To assign a physiological role to the newly discovered coding genes with unknown function, new generic methods for protein production, purification, and targeted functionalization are needed. This work presents a new vector, pCYSLIC, that allows rapid generation of Escherichia coli expression constructs via ligation-independent cloning (LIC). The vector is designed to facilitate protein purification by either Ni-NTA or GSH affinity chromatography. Subsequent proteolytic removal of affinity tags liberates an N-terminal cysteine residue that is then used for covalent modification of the target protein with different biophysical probes via protein ligation. The described system has been tested on 36 mammalian Rab GTPases, and it was demonstrated that recombinant GTPases produced with pCYSLIC could be efficiently modified with fluorescein or biotin in vitro. Finally, LIC was compared with the recently developed In-Fusion cloning method, and it was demonstrated that In-Fusion provides superior flexibility in choice of expression vector. By the application of In-Fusion cloning Cys-Rab6A GTPase with an N-terminal cysteine residue was generated employing unmodified pET30a vector and TVMV protease.     

Bone morphogenetic protein (BMP)1-3 enhances bone repair

Members of the astacin family of metalloproteinases such as human bone morphogenetic protein 1 (BMP-1) regulate morphogenesis by processing precursors to mature functional extracellular matrix (ECM) proteins and several growth factors including TGFβ, BMP2, BMP4 and GFD8. We have recently discovered that BMP1-3 isoform of the Bmp-1 gene circulates in the human plasma and is significantly increased in patients with acute bone fracture. We hypothesized that circulating BMP1-3 might have an important role in bone repair and serve as a novel bone biomarker. When administered systemically to rats with a long bone fracture and locally to rabbits with a critical size defect of the ulna, recombinant human BMP1-3 enhanced bone healing. In contrast, neutralization of the endogenous BMP1-3 by a specific polyclonal antibody delayed the bone union. Invitro BMP1-3 increased the expression of collagen type I and osteocalcin in MC3T3-E₁ osteoblast like cells, and enhanced the formation of mineralized bone nodules from bone marrow mesenchymal stem cells. We suggest that BMP1-3 is a novel systemic regulator of bone repair.     

Morphology and Phylogeny of Calyptospora paranaidji n. sp. (Eimeriorina: Calyptosporidae), an Apicomplexan Parasite of the Hepatic Tissue of Cichla piquiti Kullander & Ferreira, 2006, From a Reservoir in the Brazilian Amazon Region

The coccidians of the family Calyptosporidae are parasites of the tissue and organs of fish and aquatic invertebrates, in particular in the tropical region. In contrast with other apicomplexans of the suborder Eimeriorina, the diversity and ecology of the species of the genus Calyptospora have been poorly investigated, resulting in a lacuna that restricts the understanding of the distribution and prevalence of this group of eukaryote microparasites in the Amazon region. In the present study, the integrated comparative analysis of morphological characteristics, histological and structural traits, and the sequences of a fragment of the 18S rRNA gene, provides support for the identification of a new species of Calyptospora, found parasitizing the hepatic tissue of the piscivorous blue peacock bass, Cichla piquiti, captured in the reservoir of the Estreito hydroelectric dam on the middle Tocantins River in northern Brazil. This new species was named Calyptospora paranaidji n. sp.     

Evaluation of different chemical strategies for conjugation of oligonucleotides to peptides

We developed novel assays for high-throughput detection of one or many kinases or proteases. The assays use hundreds of different peptide substrates, each covalently linked to an oligonucleotide tag. After incubation with sample, the pool of substrates is hybridized to a microarray containing oligonucleotides complementary to the tag sequences. We screened several specific chemistries for the conjugation based on the following criteria: easy derivatization of oligonucleotides and peptides; high efficiency of the conjugation reaction; good stability of the conjugates; and satisfactory conjugate performance in our assays. We have validated selected method during the successful generation of thousands oligonucleotide-peptide conjugates.     

Genetic diversity among isolates of Paenibacillus larvae from Austria

Genetic diversity of 214 Paenibacillus larvae strains from Austria was studied. Genotyping of isolates was performed by polymerase chain reaction (PCR) with primers corresponding to enterobacterial repetitive intergenic consensus (ERIC), BOX repetitive and extragenic palindromic (REP) elements (collectively known as rep-PCR) using ERIC primers, BOX A1R and MBO REP1 primers. Using ERIC-PCR technique two genotypes could be differentiated (ERIC I and II), whereas using combined typing by BOX- and REP-PCR, five different genotypes were detected (ab, aB, Ab, AB and αb). Genotypes aB and αb are new and have not been reported in other studies using the same techniques.     

An Enhanced Adaptive Management Approach for Remediation of Legacy Mercury in the South River

Uncertainties about future conditions and the effects of chosen actions, as well as increasing resource scarcity, have been driving forces in the utilization of adaptive management strategies. However, many applications of adaptive management have been criticized for a number of shortcomings, including a limited ability to learn from actions and a lack of consideration of stakeholder objectives. To address these criticisms, we supplement existing adaptive management approaches with a decision-analytical approach that first informs the initial selection of management alternatives and then allows for periodic re-evaluation or phased implementation of management alternatives based on monitoring information and incorporation of stakeholder values. We describe the application of this enhanced adaptive management (EAM) framework to compare remedial alternatives for mercury in the South River, based on an understanding of the loading and behavior of mercury in the South River near Waynesboro, VA. The outcomes show that the ranking of remedial alternatives is influenced by uncertainty in the mercury loading model, by the relative importance placed on different criteria, and by cost estimates. The process itself demonstrates that a decision model can link project performance criteria, decision-maker preferences, environmental models, and short- and long-term monitoring information with management choices to help shape a remediation approach that provides useful information for adaptive, incremental implementation.     

Identification of Nedd4 E3 ubiquitin ligase as a binding partner and regulator of MAK-V protein kinase

MAK-V/Hunk is a scantily characterized AMPK-like protein kinase. Recent findings identified MAK-V as a pro-survival and anti-apoptotic protein and revealed its role in embryonic development as well as in tumorigenesis and metastasis. However molecular mechanisms of MAK-V action and regulation of its activity remain largely unknown. We identified Nedd4 as an interaction partner for MAK-V protein kinase. However, this HECT-type E3 ubiquitin ligase is not involved in the control of MAK-V degradation by the ubiquitin-proteasome system that regulates MAK-V abundance in cells. However, Nedd4 in an ubiquitin ligase-independent manner rescued developmental defects in Xenopus embryos induced by MAK-V overexpression, suggesting physiological relevance of interaction between MAK-V and Nedd4. This identifies Nedd4 as the first known regulator of MAK-V function.