Primary cell wall composition of pteridophytes and spermatophytes.

•  Primary cell walls (PCWs) of major vascular plant taxa were analysed as a contribution towards understanding wall evolution. •  Alcohol-insoluble residues from immature shoots were acid- or enzyme-hydrolysed and the products analysed chromatographically and electrophoretically. •  There were phylogenetic differences in abundance of mannose, galacturonate and glucuronate residues, mixed-linkage glucan (MLG) and tannins.

Change in XET activities, cell wall extensibility and hypocotyl elongation of soybean seedlings at low water potential.

In dark-grown soybean (Glycine max [L.] Merr.) seedlings, exposing the roots to water-deficient vermiculite (psi(w)=-0.

The cell wall-modifying xyloglucan endotransglycosylase/hydrolase LeXTH1 is expressed during the defence reaction of tomato against the plant parasite Cuscuta reflexa.

A suppressive subtractive hybridization technique was used to identify genes, which were induced during the early phases of the interaction between dodder (Cuscuta reflexa), a phanerogamic parasite, and its incompatible host plant tomato. One of the identified genes encodes a tomato xyloglucan endotransglycosylase/hydrolase (XTH)--an enzyme involved in cell wall elongation and restructuring. The corresponding LeXTH1 mRNA accumulated 6 h after attachment of the parasite.

Control of xyloglucan endotransglucosylase activity by salts and anionic polymers.

Crude extracts of cauliflower florets had high xyloglucan endotransglucosylase (XET) activity, but this was largely lost after partial purification and de-salting. Activity was restored (promoted up to 40-fold) by any of a wide variety of inorganic and organic salts. Optimum concentrations for Na+, K+ and NH4+ salts were typically approximately 300 mM.

Patterns and universals of mate poaching across 53 nations: the effects of sex, culture, and personality on romantically attracting another person's partner.

As part of the International Sexuality Description Project, 16,954 participants from 53 nations were administered an anonymous survey about experiences with romantic attraction. Mate poaching--romantically attracting someone who is already in a relationship--was most common in Southern Europe, South America, Western Europe, and Eastern Europe and was relatively infrequent in Africa, South/Southeast Asia, and East Asia. Evolutionary and social-role hypotheses received empirical support.

Context-dependent stimulus presentation to freely moving animals in 3D.

The presentation of controllable, dynamic sensory stimuli provides a powerful experimental paradigm, which has been extensively applied to explore sensory processing in walking and tethered flying insects. Recent advances in computer hardware and software technology provide the opportunity to track the 3D flight path of free-flying insects and process these data in real-time, opening up the possibility to present dynamic stimuli to free-flying animals. To accommodate for the increased complexity relating to 3D space, we partitioned experimental design, real-time data acquisition and stimulus control into multiple self-contained modules.

Primary cell wall metabolism: tracking the careers of wall polymers in living plant cells.

Numerous examples have been presented of enzyme activities, assayed in vitro, that appear relevant to the synthesis of structural polysaccharides, and to their assembly and subsequent degradation in the primary cell walls (PCWs) of higher plants. The accumulation of the corresponding mRNAs, and of the (immunologically recognized) proteins, has often also (or instead) been reported. However, the presence of these mRNAs, antigens and enzymic activities has rarely been shown to correspond to enzyme action in the living plant cell.

Extracellular cross-linking of xylan and xyloglucan in maize cell-suspension cultures: the role of oxidative phenolic coupling.

Cell-suspension cultures of maize ( Zea mays L.) released soluble extracellular polysaccharides (SEPs) into their medium. Some or all of the SEPs had feruloyl ester groups.

Sp2 DNA binding activity and trans-activation are negatively regulated in mammalian cells.

Previous studies have indicated that Sp2 binds poorly to GC-rich sequences bound by Sp1 and Sp3, and further functional analyses of Sp2 have been limited. To study Sp2-mediated transcription, we employed a PCR-based protocol to determine the Sp2 consensus DNA-binding sequence (5'-GGGCGGGAC-3') and performed kinetic experiments to show that Sp2 binds this consensus sequence with high affinity (225 pm) in vitro. To determine the functional consequence of Sp2 interaction with this sequence in vivo, we transformed well characterized Sp-binding sites within the dihydrofolate reductase (DHFR) promoter to consensus Sp2-binding sites.

Ethics and human rights issues experienced by nurses in leadership roles.

The aims of this study were to identify (1) the ethics and human rights issues experienced by nurses in leadership roles (NLs); (2) how frequently these issue occurred in the NLs'practices; and (3) how disturbed the NLs were by the issues. Dillman's Total Design Method (1978) for mailed surveys guided the study design. Data analysis was performed on 470 questionnaires from New England RNs in nursing leadership roles.

alpha-D-Glucuronosyl-(1-->3)-L-galactose, an unusual disaccharide from polysaccharides of the hornwort Anthoceros caucasicus.

Acid hydrolysis of cell wall-rich material from thalli of the hornwort Anthoceros caucasicus yielded substantial amounts of an unusual disaccharide (1). Hydrolysis of 1 yielded only GlcA, Gal and unhydrolysed 1. Compound 1 was identified as alpha-D-GlcpA-(1-->3)-L-Gal by 1H and 13C NMR spectroscopic analysis and by the susceptibility of its monosaccharide units to phosphorylation by enantiomer-specific kinases.

Universal sex differences in the desire for sexual variety: tests from 52 nations, 6 continents, and 13 islands.

Evolutionary psychologists have hypothesized that men and women possess both long-term and short-term mating strategies, with men's short-term strategy differentially rooted in the desire for sexual variety. In this article, findings from a cross-cultural survey of 16,288 people across 10 major world regions (including North America, South America, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, South/Southeast Asia, and East Asia) demonstrate that sex differences in the desire for sexual variety are culturally universal throughout these world regions. Sex differences were evident regardless of whether mean, median, distributional, or categorical indexes of sexual differentiation were evaluated.

Factors related to providers' decisions for and against withholding or withdrawing nutrition and/or hydration in adult patient care.

Decisions that are made near the end of life include consideration of withholding or withdrawing nutrition and/or hydration. These decisions present ethical challenges to health care providers who are caring for terminally ill patients. Clinical studies published during the last twenty years provide empirical data about the many factors that influence these decisions.

Factors related to adult patient decision making about withholding or withdrawing nutrition and/or hydration.

End-of-life decisions that focus on withholding or withdrawing nutrition and/or hydration present difficult choices at particularly vulnerable times for patients and families. Clinical ethics studies published in the last twenty years provide insight about the decision making process that can be useful to all parties involved. The purpose of the systematic research review is to synthesize empirical data about patient/surrogate decision making related to withholding or withdrawing nutritional sustenance toward the end of life, and contextual factors that influence their decision making.

Solubilisation of tomato fruit pectins by ascorbate: a possible non-enzymic mechanism of fruit softening.

The aim of this work was to test the hypothesis that endogenous ascorbate, released into the apoplast by membrane permeabilisation early in fruit ripening, could promote the solubilisation and depolymerisation of polysaccharides, and thus contribute to fruit softening. In vitro, ascorbate (1 mM), especially in the presence of traces of either Cu2+ or H2O2, solubilised up to 40% of the total pectin from the alcohol-insoluble residue of mature-green tomato (Lycopersicon esculentum Mill.) fruit.

The aerodynamics of free-flight maneuvers in Drosophila.

Using three-dimensional infrared high-speed video, we captured the wing and body kinematics of free-flying fruit flies as they performed rapid flight maneuvers. We then "replayed" the wing kinematics on a dynamically scaled robotic model to measure the aerodynamic forces produced by the wings. The results show that a fly generates rapid turns with surprisingly subtle modifications in wing motion, which nonetheless generate sufficient torque for the fly to rotate its body through each turn.

Pre-formed xyloglucans and xylans increase in molecular weight in three distinct compartments of a maize cell-suspension culture.

Cultured cells of maize ( Zea mays L.) were pulse-labelled with l-[1-(3)H]arabinose (Ara) and then monitored for 7 days. The (3)H-hemicelluloses present in three compartments (protoplasm, cell wall and culture medium) were size-fractionated and the fractions assayed for [(3)H]xyloglucans and [(3)H]xylans.

Gentiobiose: a novel oligosaccharin in ripening tomato fruit.

Two neutral disaccharides, gentiobiose [beta- D-Glc p-(1-->6)- D-Glc] and nigerose [alpha- D-Glc p-(1-->3)- D-Glc], were detected in tomato ( Lycopersicon esculentum Mill.) pericarp and locule. Gentiobiose was present in the locule of green fruit and ripe fruit at 0.

The XTH family of enzymes involved in xyloglucan endotransglucosylation and endohydrolysis: current perspectives and a new unifying nomenclature.

The polysaccharide xyloglucan is thought to play an important structural role in the primary cell wall of dicotyledons. Accordingly, there is considerable interest in understanding the biochemical basis and regulation of xyloglucan metabolism, and research over the last 16 years has identified a large family of cell wall proteins that specifically catalyze xyloglucan endohydrolysis and/or endotransglucosylation. However, a confusing and contradictory series of nomenclatures has emerged in the literature, of which xyloglucan endotransglycosylases (XETs) and endoxyloglucan transferases (EXGTs) are just two examples, to describe members of essentially the same class of genes/proteins.

Primary cell wall composition of bryophytes and charophytes.

Major differences in primary cell wall (PCW) components between non-vascular plant taxa are reported. (1) Xyloglucan: driselase digestion yielded isoprimeverose (the diagnostic repeat unit of xyloglucan) from PCW-rich material of Anthoceros (a hornwort), mosses and both leafy and thalloid liverworts, as well as numerous vascular plants, showing xyloglucan to be a PCW component in all land plants tested. In contrast, charophycean green algae (Klebsormidium flaccidium, Coleochaete scutata and Chara corallina), thought to be closely related to land plants, did not contain xyloglucan.

Xyloglucan endotransglucosylase action is high in the root elongation zone and in the trichoblasts of all vascular plants from Selaginella to Zea mays.

The endotransglucosylase action of the enzyme xyloglucan endotransglucosylase/hydrolase (XTH) was localized in the roots of diverse vascular plants: club-mosses (lycopodiophytes), ferns, gymnosperms, monocots, and dicots. High action was always found in the epidermis cell wall of the elongation zone and in trichoblasts in the differentiation zone. Clearly XTH and its action in root development evolved before the evolutionary divergence of ferns and seed plants and also of the lycopodiophytes and euphyllophytes.

Echocardiography improves detection of rejection after heterotopic mouse cardiac transplantation.

Background: Current assessments of cardiac rejection in murine transplant models rely on subjective estimates of the force of the palpable heart beat that have limited sensitivity and precision.

Methods: We used 2-dimensional echocardiography to evaluate changes in left ventricular posterior wall thickness (PWT) in a heterotopic cardiac mouse transplant model of rejection. Nine allografts and 6 isografts were imaged daily for 6 days and harvested.

Formation of Di-Isodityrosine and Loss of Isodityrosine in the Cell Walls of Tomato Cell-Suspension Cultures Treated with Fungal Elicitors or H2O2.

About 84% of the hydroxyproline residues in a cell culture of tomato (Lycopersicon esculentum x Lycopersicon peruvianum) were present in phenol-inextractable (i.e. covalently wall-bound) material.

Development of a model of moral distress in military nursing.

The purpose of this article is to describe the development of a model of moral distress in military nursing. The model evolved through an analysis of the moral distress and military nursing literature, and the analysis of interview data obtained from US Army Nurse Corps officers (n = 13). Stories of moral distress (n = 10) given by the interview participants identified the process of the moral distress experience among military nurses and the dimensions of the military nursing moral distress phenomenon.