A complex population structure of the cassava pathogen Xanthomonas axonopodis pv. manihotis in recent years in the Caribbean Region of Colombia.

Cassava bacterial blight, caused by Xanthomonas axonopodis pv. manihotis (Xam), is the most important bacterial disease affecting this crop. A continuous surveillance of the pathogen population dynamics is required to develop an efficient disease management program.

Triosephosphate isomerase is dispensable in vitro yet essential for Mycobacterium tuberculosis to establish infection.

ABSTRACT Triosephosphate isomerase (TPI) catalyzes the interconversion of dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (G3P). This reaction is required for glycolysis and gluconeogenesis, and tpi has been predicted to be essential for growth of Mycobacterium tuberculosis. However, when studying a conditionally regulated tpi knockdown mutant, we noticed that depletion of TPI reduced growth of M.

An outer membrane channel protein of Mycobacterium tuberculosis with exotoxin activity.

The ability to control the timing and mode of host cell death plays a pivotal role in microbial infections. Many bacteria use toxins to kill host cells and evade immune responses. Such toxins are unknown in Mycobacterium tuberculosis.

A Sedna-like body with a perihelion of 80 astronomical units.

The observable Solar System can be divided into three distinct regions: the rocky terrestrial planets including the asteroids at 0.39 to 4.2 astronomical units (AU) from the Sun (where 1 AU is the mean distance between Earth and the Sun), the gas giant planets at 5 to 30 AU from the Sun, and the icy Kuiper belt objects at 30 to 50 AU from the Sun.

Common causes for unsatisfactory Pap tests in a high-risk population: insights into a yet unresolved problem in gynecologic cytology.

Introduction: Although the rates are generally low (0.2%-10%), unsatisfactory Papanicolaou (Pap) tests are associated with an increased risk of epithelial lesions on subsequent follow-up. Therefore, some studies have recommended extra laboratory processing, resampling of patients, and more recently, human papillomavirus testing.

The EvoDevoCI: a concept inventory for gauging students' understanding of evolutionary developmental biology.

The American Association for the Advancement of Science 2011 report Vision and Change in Undergraduate Biology Education encourages the teaching of developmental biology as an important part of teaching evolution. Recently, however, we found that biology majors often lack the developmental knowledge needed to understand evolutionary developmental biology, or "evo-devo." To assist in efforts to improve evo-devo instruction among undergraduate biology majors, we designed a concept inventory (CI) for evolutionary developmental biology, the EvoDevoCI.

Genomic survey of pathogenicity determinants and VNTR markers in the cassava bacterial pathogen Xanthomonas axonopodis pv. Manihotis strain CIO151.

Xanthomonas axonopodis pv. manihotis (Xam) is the causal agent of bacterial blight of cassava, which is among the main components of human diet in Africa and South America. Current information about the molecular pathogenicity factors involved in the infection process of this organism is limited.

Adjuvant chemoradiation for resected gallbladder cancer: Treatment strategies for one of the leading causes of cancer death in Chilean women.

Background: Gallbladder cancer (GBC) is the second leading cause of cancer death in women in Chile. Even after curative surgery, prognosis is grim. To evaluate acute and late toxicity and efficacy of adjuvant chemoradiation (CRT) after curatively resected GBC.

Getting to evo-devo: concepts and challenges for students learning evolutionary developmental biology.

To examine how well biology majors have achieved the necessary foundation in evolution, numerous studies have examined how students learn natural selection. However, no studies to date have examined how students learn developmental aspects of evolution (evo-devo). Although evo-devo plays an increasing role in undergraduate biology curricula, we find that instruction often addresses development cursorily, with most of the treatment embedded within instruction on evolution.

Non-covalent interactions: complexes of guanidinium with DNA and RNA nucleobases.

Considering that guanidine-based derivatives are good DNA minor groove binders, we have theoretically studied, using the Polarizable Continuum model mimicking water solvation, the complexes formed by the biologically relevant guanidinium cation and the DNA and RNA nucleobases (adenine, guanine, cytosine, thymine, and uracil). The interactions established within these complexes both by hydrogen bonds and by cation-π interactions have been analyzed by means of the Atoms in Molecules and Natural Bond Orbital approaches. Moreover, maps of electron density difference have been produced to understand the cation-π complexes.

Rescue of amyloid-Beta-induced inhibition of nicotinic acetylcholine receptors by a peptide homologous to the nicotine binding domain of the alpha 7 subtype.

Alzheimer's disease (AD) is characterized by brain accumulation of the neurotoxic amyloid-β peptide (Aβ) and by loss of cholinergic neurons and nicotinic acetylcholine receptors (nAChRs). Recent evidence indicates that memory loss and cognitive decline in AD correlate better with the amount of soluble Aβ than with the extent of amyloid plaque deposits in affected brains. Inhibition of nAChRs by soluble Aβ40 is suggested to contribute to early cholinergic dysfunction in AD.

Orthogonal interactions between nitryl derivatives and electron donors: pnictogen bonds.

Pnictogen complexes between nitryl derivatives (NO2X, X = CN, F, Cl, Br, NO2, OH, CCH, and C2H3) and molecules acting as Lewis bases (H2O, H3N, CO, HCN, HNC and HCCH) have been obtained at the MP2/aug-cc-pVTZ computational level. A total of 53 minima have been located. Their energy, geometry, DFT-SAPT energy terms, electronic properties (NBO, AIM, ELF, and NCI) and NMR shieldings have been calculated and analyzed.

Intramolecular pnicogen interactions in PHF-(CH2)(n)-PHF (n=2-6) systems.

A computational study of the intramolecular pnicogen bond in PHF-(CH2)n-PHF (n=2-6) systems was carried out. For each compound, two different conformations, (R,R) and (R,S), were considered on the basis of the chirality of the phosphine groups. The characteristics of the closed conformers, in which the pnicogen interaction occurs, were compared with those of the extended conformer.

Accelerated numerical processing of electronically recorded holograms with reduced speckle noise.

The numerical reconstruction of digitally recorded holograms suffers from speckle noise. An accelerated method that uses general-purpose computing in graphics processing units to reduce that noise is shown. The proposed methodology utilizes parallelized algorithms to record, reconstruct, and superimpose multiple uncorrelated holograms of a static scene.

Glucose phosphorylation is required for Mycobacterium tuberculosis persistence in mice.

Mycobacterium tuberculosis (Mtb) is thought to preferentially rely on fatty acid metabolism to both establish and maintain chronic infections. Its metabolic network, however, allows efficient co-catabolism of multiple carbon substrates. To gain insight into the importance of carbohydrate substrates for Mtb pathogenesis we evaluated the role of glucose phosphorylation, the first reaction in glycolysis.

In ADHD patients performing the Counting Stroop task: a social neuroscience approach.

Attention Deficit/Hyperactivity Disorder (ADHD) symptoms are manifested in social dynamics. In this study, the brain activity of eight child and adolescent patients diagnosed with ADHD was examined while they performed the Counting Stroop task and results were interpreted using social neuroscience premises. Brain activity was identified in frontal, parietal, and temporal regions related to the orienting system of attention and with linguistic, facial recognition, and mnemonic processes.

In utero and childhood polybrominated diphenyl ether (PBDE) exposures and neurodevelopment in the CHAMACOS study.

Background: California children's exposures to polybrominated diphenyl ether flame retardants (PBDEs) are among the highest worldwide. PBDEs are known endocrine disruptors and neurotoxicants in animals.

Objective: Here we investigate the relation of in utero and child PBDE exposure to neurobehavioral development among participants in CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas), a California birth cohort.

Kinin-B2 receptor activity determines the differentiation fate of neural stem cells.

Bradykinin is not only important for inflammation and blood pressure regulation, but also involved in neuromodulation and neuroprotection. Here we describe novel functions for bradykinin and the kinin-B2 receptor (B2BkR) in differentiation of neural stem cells. In the presence of the B2BkR antagonist HOE-140 during rat neurosphere differentiation, neuron-specific β3-tubulin and enolase expression was reduced together with an increase in glial protein expression, indicating that bradykinin-induced receptor activity contributes to neurogenesis.

Stem cells and modeling of autism spectrum disorders.

Human neurons, generated from reprogrammed somatic cells isolated from live patients, bring a new perspective on the understanding of Autism Spectrum Disorders (ASD). The new technology can nicely complement other models for basic research and the development of therapeutic compounds aiming to revert or ameliorate the condition. Here, we discuss recent advances on the use of stem cells and other models to study ASDs, as well as their limitations, implications and future perspectives.

Cholinesterase and paraoxonase (PON1) enzyme activities in Mexican-American mothers and children from an agricultural community.

Exposure to organophosphate and carbamate pesticides can lead to neurotoxic effects through inhibition of cholinesterase enzymes. The paraoxonase (PON1) enzyme can detoxify oxon derivatives of some organophosphates. Lower PON1, acetylcholinesterase, and butyrylcholinesterase activities have been reported in newborns relative to adults, suggesting increased susceptibility to organophosphate exposure in young children.

Interactions between the NO-citrulline cycle and brain-derived neurotrophic factor in differentiation of neural stem cells.

The diffusible messenger NO plays multiple roles in neuroprotection, neurodegeneration, and brain plasticity. Argininosuccinate synthase (AS) is a ubiquitous enzyme in mammals and the key enzyme of the NO-citrulline cycle, because it provides the substrate L-arginine for subsequent NO synthesis by inducible, endothelial, and neuronal NO synthase (NOS). Here, we provide evidence for the participation of AS and of the NO-citrulline cycle in the progress of differentiation of neural stem cells (NSC) into neurons, astrocytes, and oligodendrocytes.

Absence of FKBP10 in recessive type XI osteogenesis imperfecta leads to diminished collagen cross-linking and reduced collagen deposition in extracellular matrix.

Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.

Weak interactions between hypohalous acids and dimethylchalcogens.

The complexes formed between dimethylchalcogens X(CH(3))(2) (X = S, Se, and Te) and hypohalous acids YOH (Y = F, Cl, Br, and I) have been studied at the MP2/aug'-cc-pVTZ computational level, five minima structures being located. Two of them correspond to hydrogen bonds (HB), another two to halogen bonds (XB) with the chalcogen acting as an electron donor, the last one showing a C-H···O contact. The most stable complexes of IOH and BrOH acids present halogen···chalcogen interactions with interaction energies, E(i), up to -49 kJ mol(-1).

The expression of irx7 in the inner nuclear layer of zebrafish retina is essential for a proper retinal development and lamination.

Irx7, a member in the zebrafish iroquois transcription factor (TF) family, has been shown to control brain patterning. During retinal development, irx7's expression was found to appear exclusively in the inner nuclear layer (INL) as soon as the prospective INL cells withdraw from the cell cycle and during retinal lamination. In Irx7-deficient retinas, the formation of a proper retinal lamination was disrupted and the differentiation of INL cell types, including amacrine, horizontal, bipolar and Muller cells, was compromised.

Competition and interplay between σ-hole and π-hole interactions: a computational study of 1:1 and 1:2 complexes of nitryl halides (O2NX) with ammonia.

Quantum calculations at the MP2/cc-pVTZ, MP2/aug-cc-pVTZ, and CCSD(T)/cc-pVTZ levels have been used to examine 1:1 and 1:2 complexes between O(2)NX (X = Cl, Br, and I) with NH(3). The interaction of the lone pair of the ammonia with the σ-hole and π-hole of O(2)NX molecules have been considered. The 1:1 complexes can easily be differentiated using the stretching frequency of the N-X bond.