bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between clinical indicators, coping styles, perceived support and diabetes‐related distress among adults with type 2 diabetes
Authors: Karlsen Bjørg , Oftedal Bjørg , Bru Edvin
Published: June 2011

karlsen b., oftedal b. & bru e. (2012) The relationship between clinical indicators, coping styles, perceived support and diabetes‐related distress among adults with type 2 diabetes.Journal of Advanced Nursing 68(2), 391–401.

Aim: This article is a report of a cross‐sectional study examining the degree to which clinical indicators, coping styles and perceived support from healthcare professionals and family are related to diabetes‐related distress.

Background: Many people with type 2 diabetes experience high levels of distress stemming from concerns and worries associated with their disease. Diabetes‐related distress has predominantly been studied in relation to diabetes management and metabolic control, and to some extent in relation to coping styles and perceived social support. To date, little is known about the relative contribution of clinical indicators, coping styles and perceptions of social support to perceived distress among people with type 2 diabetes.

Methods: A sample comprising 425 Norwegian adults, aged 30–70, with type 2 diabetes, completed questionnaires assessing coping styles, perceived social support from health professionals and family and diabetes‐related distress assessed by the Problem Areas in Diabetes Scale. Demographical and clinical data were collected by self‐report. Data were collected in October 2008.

Findings: Results from the regression analyses showed a greater variance in emotional distress accounted for by coping styles (21·3%) and perceived support (19·7%) than by clinical indicators (5·8%).

Conclusion: Findings may indicate that healthcare providers should pay more attention to non‐clinical factors such as coping styles and social support, when addressing diabetes‐related distress. They should also be aware that interventions based on psychosocial approaches may primarily influence distress, and not necessarily metabolic control.
Reduced size and starvation resistance in adult mosquitoes,Aedes notoscriptus, exposed to predation cues as larvae
Authors: van Uitregt Vincent O. , Hurst Timothy P. , Wilson Robbie S.
Published: June 2011

1. Many prey organisms exhibit adaptive phenotypic plasticity in life‐history traits that facilitate a better chance of survival in the presence of predators. The evolution of such plastic traits requires that the defensive phenotype incurs a cost in the absence of predation.

2. Model systems that are used to examine predator‐induced defences are often organisms with complex life histories that only induce defences during the larval stage. While many studies have detected costs of inducible defences during the larval stage, detecting the costs of larval defences after metamorphosis is also important.

3. We examine the benefits and costs of inducible larval defences in the urban mosquito,Aedes notoscriptus, by rearing them in the presence and absence of predation cues. We compared survival of larvae inducing behavioural defences, when exposed to predation cues, in predation trials with predatory fishHypseleotris galiito that of larvae reared in the absence predation cues. We also compared life‐history traits of predator‐exposed larvae to larvae reared in control conditions.

4. Larvae exposed to chemical predation cues limited activity and were able to avoid predation for longer in trials withH. galii. However, predator‐exposed larvae suffered retarded larval growth and development, were smaller at metamorphosis and less resistant to starvation as adults.

5. While it is difficult to understand the ‘fitness costs’ that poorer starvation resistance might confer to adult mosquitoes, it is likely that smaller adult size of predator‐exposed individuals would reduce fitness, particularly for females where body size limits the size of blood meal they could take to facilitate egg production. We suggest that the demonstrable costs of inducible defences in mosquito larvae make this a good system for testing theoretical models for the evolutionary maintenance of adaptive phenotypic plasticity.
Evaluation of the psychometric properties of a modified Chinese version of the Caregiver Task Inventory – refinement and psychometric testing of the Chinese Caregiver Task Inventory: a confirmatory factor analysis
Authors: Lee Regina LT , Mok Esther SB
Published: June 2011

Aim.  To test the reliability and validity of the modified Chinese version of the Caregiver Task Inventory.

Background.  The original Caregiver Task Inventory was developed in 1983 by Clark and Rakowski in the USA. It was used to measure Chinese family caregivers’ needs in Hong Kong. Its failure to evaluate the psychometric properties of the instrument measuring the needs of family caregivers across cultures limited its scientific rigor.

Design.  A quantitative study method was used to test the psychometrics of the modified Chinese version of the Caregiver Task Inventory.

Methods.  A convenience sample of 114 family caregivers completed the Caregiver Task Inventory in 2005 to test different aspects of the validity and reliability and confirm items of the short form of the Chinese Caregiver Task Inventory‐25.

Results.  The content validity of the 25 items of the Chinese Caregiver Task Inventory was validated by six experts, who assessed the correlation between caregiving tasks and the five refined sub‐scales. The construct validity was determined by confirmatory factor analysis (CFA). The χ2 goodness‐of‐fit, χ2: df ratio, goodness‐of‐fit index (GFI), adjusted GFI and root mean square residual were obtained and used to assess the fit of the model. The internal consistency and stability of the Chinese Caregiver Task Inventory‐25 were determined by Cronbach’s method (0·93) and the internal reliability (item total correlation) for the five refined sub‐scales ranged from 0·67–0·86. CFA and internal consistency analysis showed a strong degree of fit between the conceptualisation and the development of the measurement.

Conclusions.  The Chinese Caregiver Task Inventory‐25 is a relevant and culturally appropriate research instrument to measure the needs of Chinese family caregivers.

Relevance to clinical practice.  This study reveals that stroke nurses should assess the impacts of caregiving tasks on caregivers’ physical and psychological stress levels prior to planning relevant interventions.
A systematic review of the effects of e‐health on chronically ill patients
Authors: Eland‐de Kok Petra , van Os‐Medendorp Harmieke , Vergouwe‐Meijer Aly , Bruijnzeel‐Koomen Carla , Ros Wynand
Published: June 2011

Aims and objectives.  We aimed to investigate whether e‐health is equal to or better than usual face‐to‐face care with regard to outcomes on health, quality of life, patient satisfaction and costs. Therefore, we systematically reviewed the literature on e‐health in chronically ill patients compared with or as an addition to usual care.

Background.  Interactive websites on internet are increasingly used to inform and treat patients. This type of contact between patients and health care providers, which is called e‐health, is easily accessible and particularly interesting for chronically ill patients.

Design.  A systematic review.

Methods.  We searched the databases PubMed, CINAHL, the Cochrane Database of systematic reviews, DARE and CENTRAL for articles published between January 2000–July 2009.

Results.  The search strategy yielded in total 695 possibly relevant references, which resulted in 12 RCTs after application of the in‐ and exclusion criteria. Most of the studies were well designed according to the Cochrane criteria for RCTs. The studies are divided into e‐health vs. usual care and e‐health as addition to usual care. e‐Health consisted of monitoring, treatment instructions, self‐management training and general information and communication between patient and caregiver. Most of the studies showed small to moderate positive effects on health outcomes. Cost‐effectiveness, quality of life and patient satisfaction were rarely investigated in the included studies.

Conclusions.  e‐Health interventions for chronically ill patients, offered instead of usual care or in addition to usual care, lead to small to moderate positive effects on primary health outcomes. However, the evidence was not fully convincing, because of the limited number of studies available and the methodological limitations. Further research is needed to confirm the cost‐effectiveness of e‐health interventions for patients with chronic diseases.

Relevance to clinical practice.  e‐Health is a promising tool for treatment and self‐management training of chronically ill patients.
Narratives of the heart: telling the story of children with a cardiac condition through a bead program
Authors: Redshaw Sarah , Wilson Valerie , Scarfe Gabrielle , Dengler Lexi
Published: June 2011

Aims. To present and discuss the significance of a bead program in assisting families to put together the story of a child’s journey through cardiac intervention. The main focus of the article is the importance to families of developing a narrative in making sense of the experience of discovering their child has a cardiac condition and how this is enhanced by the bead program.

Background. The Heart Beads Program involved giving families beads related to procedures and processes the children undergo while they are in hospital. Research on narratives related to illness suggests that forming a narrative that incorporates the health condition facilitates the ability to talk about these experiences and helps to make sense of and deal with the stressors related to such traumatic life events.

Design. A qualitative methodology was used to evaluate the program employing semi‐structured interviews and content analysis following a grounded theory approach.

Methods. Interviews were undertaken with 11 families to highlight their experiences of being involved in the Heart Beads Program. Themes were identified from the interviews and critical discussion was used to structure and connect the themes.

Results. The major theme that emerged from the analysis of the interviews was the importance of the beads in enabling the telling of the child’s story. Five subthemes were identified in this theme: symbolism, encouraging/uplifting, acknowledgement, connection with others and imagining the future. The themes are outlined and expressed through specific comments from interviews.

Conclusions. The Heart Beads are seen as presenting a significant way for children and families to comprehend their time in hospital as part of the child’s life story.

Relevance to clinical practice. The program can offer the opportunity for health care professionals to relate to the child and family’s story and to engage with that story in a person centred way.
Comparison of 1:1 and 1:m CSCL environment for collaborative concept mapping
Authors: Lin C.‐P. , Wong L.‐H. , Shao Y.‐J.
Published: June 2011

This paper reports an investigation into the effects of collaborative concept mapping in a digital learning environment, in terms of students' overall learning gains, knowledge retention, quality of student artefacts (the collaboratively created concept maps), interactive patterns, and learning perceptions. Sixty‐four 12‐year‐old students from two 6th grade classes (32 from each class) participated in the study. Guided by the methodology of quasi‐experimental research, group scribbles 1.0 was adopted in which students carried out collaborative concept mapping activities for social studies in two different settings: (1) 1:1 (one‐device‐per‐student) – students working in pairs with one Tablet PC assigned to each of them; and (2) 1:m (one‐device‐to‐many‐students) – multiple students sharing a Tablet PC. Both settings were evaluated and the interactional patterns of the student groups' concept mapping were identified. The results indicated that in both 1:1 and 1:m settings, students had improved their learning results and retention. Nevertheless, while 1:1 groups had demonstrated more consistency in group participation, improved communication and interaction, the 1:m groups had instead generated superior artefacts as all the notes were well discussed among the group members. The findings suggest that a higher quality of collaborative processes does not necessarily lead to improved student artefacts.
Use of a collaborative database for epidemiological analyses and professional practice evaluation
Authors: Decullier Evelyne , Juillard Laurent , Bailly Mathilde , Maurice Christelle , Favé Sophie , Roux Adeline , Favre Hélène , Laville Maurice
Published: June 2011

Rationale  In nephrology, the NEOERICA project assessed the feasibility of the diagnosis scheme based on a general practice database. This approach opened a new area where routinely collected data could be used for purposes other than patient management, such as epidemiological analysis and professional practice evaluation. In Lyon, the TIRCEL network is made up of a coordination team and an online database. In 2008, a total of 468 professionals participated and 983 patients were in the database corresponding to 4114 consultations and 9250 biological assessments.

Objective  To investigate the impact of a quality control process on the data from operational databases.

Methods  We set up a quality control process and we described the impact of this process on data. We also specifically investigated the role of measurement scales in error frequency and we studied the impact of data quality on variables which could be used for professional practice evaluation.

Results  Quality control allowed us to detect as inconsistent data 7.5% of tested data. This rate is linked to the parameters and varied from less than 1% (weight, diastolic blood pressure and urinary sodium) to more than 30% (serum iron and ferritin). Quality control led mainly to the validation of the identified data for 80.4%, a direct correction was realized for 12.9%, 5.6% by the lab and only 1.2% were set to missing. Average proteinuria was modified with the quality control process (2.09 g per 24 hours vs. 0.82 g per 24 hours); however, the median remained stable (0.21 g per 24 hours).

Conclusion  Specialty databases such as TIRCEL could not be used for epidemiological research or for the extraction of indicators for professional practice evaluation without strict quality control or the set‐up of data‐entering limits and alarms.
Digital image processing versus visual assessment of chewed two‐colour wax in mixing ability tests
Authors: Van Der BILT A. , SPEKSNIJDER C. M. , De LIZ POCZTARUK R. , ABBINK J. H.
Published: June 2011

Summary  Two‐colour chewing gum and wax have been widely used as test foods to evaluate the ability to mix and knead a food bolus. The mixing of the colours has been assessed by computer analysis or by visual inspection. Reports contradict each other about whether computer analysis and visual assessment could equally well discriminate between the masticatory performances of groups of participants with different dental status. This study compares the results of computer analysis of digital images of chewed two‐colour wax with the results of visual assessment of these images. Sixty healthy subjects participated and chewed on red–blue wax for 5, 10, 15 and 20 chewing strokes. The subjects were divided into three groups of 20, matched for age and gender, according to their dental status: natural dentition, full dentures and maxillary denture plus implant‐supported mandibular overdenture. Mixing of the chewed wax was determined by computer analysis of images of the wax and by visual assessment of the images by five examiners. Both the computer method and the observers were able to distinguish the mixing abilities of the dentate subjects from the two denture wearer groups. Computer analysis could also discriminate the mixing abilities of the two denture groups. However, observers were not able to distinguish the mixing abilities of the two denture groups after 5, 10 and 15 chewing strokes. Only after 20 chewing strokes, they could detect a significant difference in mixing ability.
Comparison of ambulatory and polysomnographic recording of jaw muscle activity during sleep in normal subjects
Authors: YAMAGUCHI T. , ABE S. , ROMPRÉ P. H. , MANZINI C. , LAVIGNE G. J.
Published: June 2011

Summary  Clinicians and investigators need a simple and reliable recording device to diagnose or monitor sleep bruxism (SB). The aim of this study was to compare recordings made with an ambulatory electromyographic telemetry recorder (TEL‐EMG) with those made with standard sleep laboratory polysomnography with synchronised audio‐visual recording (PSG‐AV). Eight volunteer subjects without current history of tooth grinding spent one night in a sleep laboratory. Simultaneous bilateral masseter EMG recordings were made with a TEL‐EMG and standard PSG. All types of oromotor activity and rhythmic masseter muscle activity (RMMA), typical of SB, were independently scored by two individuals. Correlation and intra‐class coefficient (ICC) were estimated for scores on each system. The TEL‐EMG was highly sensitive to detect RMMA (0·988), but with low positive predictive value (0·231) because of a high rate of oromotor activity detection (e.g. swallowing and scratching). Almost 72% of false‐positive oromotor activity scored with the TEL‐EMG occurred during the transient wake period of sleep. A non‐significant correlation between recording systems was found (r = 0·49). Because of the high frequency of wake periods during sleep, ICC was low (0·47), and the removal of the influence of wake periods improved the detection reliability of the TEL‐EMG (ICC = 0·88). The TEL‐EMG is sensitive to detect RMMA in normal subjects. However, it obtained a high rate of false‐positive detections because of the presence of frequent oromotor activities and transient wake periods of sleep. New algorithms are needed to improve the validity of TEL‐EMG recordings.
Reduced sleep quality in healthy girls at risk for depression
Authors: CHEN MICHAEL C. , BURLEY HANNAH W. , GOTLIB IAN H.
Published: June 2011

Depression is characterized by sleep difficulties, but the extent to which subjective and objective sleep disturbances precede depression are unclear. This study was designed to examine perceptions of sleep quality in addition to actigraphy‐ and diary‐measured sleep variables in healthy girls at low and high familial risk for major depressive disorder. Forty‐four healthy daughters and their mothers completed a week of daily sleep diary and actigraphy; 24 girls had mothers with no history of psychopathology (low risk, mean age 14.92 years), and 20 girls had mothers with recurrent depression during the daughter’s lifetime (high risk, mean age 14.12 years). All daughters had no current or past psychopathology. High‐risk girls reported significantly poorer subjective sleep quality than did low‐risk girls (P = 0.001). The two groups of participants did not differ in actigraphy‐ or diary‐measured sleep duration, onset latency or snooze duration. Healthy girls at high familial risk for depression report poorer sleep quality than do girls at low risk for depression, despite the absence of group differences in objective sleep disturbances as measured by actigraphy or daily diary. This pattern of findings may reflect a broader cognitive or physiological phenotype of risk for depression.
Role for Sit4p‐dependent mitochondrial dysfunction in mediating the shortened chronological lifespan and oxidative stress sensitivity of Isc1p‐deficient cells
Authors: Barbosa António Daniel , Osório Hugo , Sims Kellie J. , Almeida Teresa , Alves Mariana , Bielawski Jacek , Amorim Maria Amélia , Moradas‐Ferreira Pedro , Hannun Yusuf A. , Costa Vítor
Published: June 2011

Saccharomyces cerevisiae cells lacking Isc1p, an orthologue of mammalian neutral sphingomyelinase 2, display a shortened lifespan and an increased sensitivity to oxidative stress. A lipidomic analysis revealed specific changes in sphingolipids that accompanied the premature ageing of Isc1p‐deficient cells under severe calorie restriction conditions, including a decrease of dihydrosphingosine levels and an increase of dihydro‐C26‐ceramide and phyto‐C26‐ceramide levels, the latter raising the possibility of activation of ceramide‐dependent protein phosphatases. Consequently, deletion of the SIT4 gene, which encodes for the catalytic subunit of type 2A ceramide‐activated protein phosphatase in yeast, abolished the premature ageing and hydrogen peroxide sensitivity of isc1Δ cells. SIT4 deletion also abolished the respiratory defects and catalase A deficiency exhibited by isc1Δ mutants. These results are consistent with catabolic derepression associated with the loss of Sit4p. The overall results show that Isc1p is an upstream regulator of Sit4p and implicate Sit4p activation in mitochondrial dysfunction leading to the shortened chronological lifespan and oxidative stress sensitivity of isc1Δ mutants.
The secretion ATPase ComGA is required for the binding and transport of transforming DNA
Authors: Briley Jr Kenneth , Dorsey‐Oresto Angella , Prepiak Peter , Dias Miguel J. , Mann Jessica M. , Dubnau David
Published: June 2011

Transformation requires specialized proteins to facilitate the binding and uptake of DNA. The genes of the Bacillus subtilis comG operon (comGA–G) are required for transformation and to assemble a structure, the pseudopilus, in the cell envelope. No role for the pseudopilus has been established and the functions of the individual comG genes are unknown. We show that among the comG genes, only comGA is absolutely required for DNA binding to the cell surface. ComEA, an integral membrane DNA‐binding protein plays a minor role in the initial binding step, while an unidentified protein which communicates with ComGA must be directly responsible for binding to the cell. We show that the use of resistance to DNase to measure ‘DNA uptake’ reflects the movement of transforming DNA to a protected state in which it is not irreversibly associated with the protoplast, and presumably resides outside the cell membrane, in the periplasm or associated with the cell wall. We suggest that ComGA is needed for the acquisition of DNase resistance as well as for the binding of DNA to the cell surface. Finally, we show that the pseudopilus is required for DNA uptake and we offer a revised model for the transformation process.
Duodenal ulcer disease, gastroduodenal motor function and reflux esophagitis – a cross‐sectional survey in a subset of Taiwanese patients
Authors: Su Y.‐C. , Chen Y.‐W. , Wu D.‐C. , Wang W.‐M. , Jan C.‐M.
Published: June 2011

Background  To investigate the association between the gastric emptying rate and the presence of erosive esophagitis in duodenal ulcer (DU) patients among a population with high prevalence of Helicobacter pylori infection.

Methods  Cross‐sectional survey was performed in a cohort of 60 male patients with either active or healed DU, with or without the presence of erosive esophagitis. Clinical and social‐demographic data, blood level of fasting gastrin, pepsinogen I & I/II ratio, and scintigraphic measurement of half emptying time (t1/2) of the solid phase gastric emptying were evaluated.

Key Results  Patients with active DU and erosive esophagitis tended to have higher plasma level of fasting gastrin than those without erosive esophagitis (75.11 ± 13.74 vs 45.81 ± 5.06 pg mL−1, P = 0.059). In the absence of H. pylori infection, patients with healed DU and erosive esophagitis had a trend to have longer half‐emptying time (t1/2: 96.5 ± 6.4 vs 69.1 ± 11.3 min, P = 0.0572) than those without erosive esophagitis, and statistically significant longer after excluding those diagnosed with hiatal hernia (t1/2: 100.8 ± 7.9 min vs 69.1 ± 11.3 min, P < 0.05) from the former group. Among the healed DU patients, those with negative H. pylori infection, hiatal hernia and overweight (body mass index ≥24) had significantly increased risk of severe esophagitis.

Conclusions & Inferences  Presence of erosive esophagitis in a subset of Taiwanese patients with healed DU and negative H. pylori status was associated with slower solid phase gastric emptying.
Producing parasitic helminth reference and draft genomes at the Wellcome Trust Sanger Institute
Authors: HOLROYD N. , SANCHEZ‐FLORES A.
Published: June 2011

The Wellcome Trust Sanger Institute (WTSI) is producing de novo reference quality genomes for parasitic helminth species from platyhelminth tapeworms (cestodes), flukes (trematodes) and roundworms (nematodes) primarily using second‐generation (Illumina and 454) sequencing technologies. The reference genomes will be followed with draft coverage from a number of related strains or species. Comparing species‐ or strain‐specific differences will help to unravel the genomic basis for differences in the organism’s biology and ultimately contribute towards identifying potential novel targets for vaccine therapies. Second‐generation sequencing technologies are revolutionizing parasite genomics. This article reviews the impact that sequencing technologies has had on genomics and how it has shaped the parasitic helminth genome sequencing initiative at WTSI.
Modulations of high‐voltage activated Ca2+ channels in the central neurones of Spodoptera exigua by chlorantraniliprole
Authors: LI YUXIN , MAO MINGZHEN , LI YIMING , XIONG LIXIA , LI ZHENGMING , XU JUNYING
Published: June 2011

The modulation of voltage‐gated calcium channels by chlorantraniliprole in the central neurones isolated from third‐instar larvae of Spodoptera exigua is studied by the whole‐cell patch‐clamp technique. The current of calcium in the third‐instar larvae of S. exigua is identified as a high‐voltage activated Ca2+ current. During the 10‐min recording, the current–voltage relationship curves of whole‐cell calcium channels are shifted in a negative direction by 10 mV compared with the control group. The fact that the gravity rundown of calcium current in the treated group is more apparent than in the control group demonstrates that the open channels are constantly inactivated. In addition, chlorantraniliprole inhibits the recorded calcium currents in a concentration‐dependent manner, which is irreversible on washout.
Spatial variation in photosynthetic CO2 carbon and oxygen isotope discrimination along leaves of the monocot triticale (Triticum × Secale) relates to mesophyll conductance and the Péclet effect
Authors: KODAMA NAOMI , COUSINS ASAPH , TU KEVIN P. , BARBOUR MARGARET M.
Published: June 2011

Carbon and oxygen isotope discrimination of CO2 during photosynthesis (Δ13Cobs and Δ18Oobs) were measured along a monocot leaf, triticale (Triticum × Secale). Both Δ13Cobs and Δ18Oobs increased towards the leaf tip. While this was expected for Δ18Oobs, because of progressive enrichment of leaf water associated with the Péclet effect, the result was surprising for Δ13Cobs. To explore parameters determining this pattern, we measured activities of key photosynthetic enzymes [ribulose bis‐phosphate carboxylase‐oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEPC) and carbonic anhydrase) as well as maximum carboxylation and electron transport rates (Vcmax and Jmax) along the leaf. Patterns in leaf internal anatomy along the leaf were also quantified. Mesophyll conductance (gm) is known to have a strong influence on Δ13Cobs, so we used three commonly used estimation methods to quantify variation in gm along the leaf. Variation in Δ13Cobs was correlated with gm and chloroplast surface area facing the intercellular air space, but unrelated to photosynthetic enzyme activity.

The observed variation could cause errors at higher scales if the appropriate portion of a leaf is not chosen for leaf‐level measurements and model parameterization. Our study shows that one‐third of the way from the base of the leaf represents the most appropriate portion to enclose in the leaf chamber.
Mycorrhizal symbiosis stimulates endoreduplication in angiosperms
Authors: BAINARD L. D. , BAINARD J. D. , NEWMASTER S. G. , KLIRONOMOS J. N.
Published: June 2011

Symbiotic and parasitic relationships can alter the degree of endoreduplication in plant cells, and a limited number of studies have documented this occurrence in root cells colonized by arbuscular mycorrhizal (AM) fungi. However, this phenomenon has not been tested in a wide range of plant species, including species that are non‐endopolyploid and those that do not associate with AM fungi. We grew 37 species belonging to 16 plant families, with a range of genome sizes and a range in the degree of endopolyploidy. The endoreduplication index (EI) was compared between plants that were inoculated with Glomus irregulare and plants that were not inoculated. Of the species colonized with AM fungi, 22 of the 25 species had a significant increase in endopolyploid root nuclei over non‐mycorrhizal plants, including species that do not normally exhibit endopolyploidy. Changes in the EI were strongly correlated (R2 = 0.619) with the proportion of root length colonized by arbuscules. No change was detected in the EI for the 12 non‐mycorrhizal species. This work indicates that colonization by symbiotic fungi involves a mechanism to increase nuclear DNA content in roots across many angiosperm groups and is likely linked to increased metabolism and protein production.
Physiological impact of mitochondrial alternative oxidase on photosynthesis and growth in Arabidopsis thaliana
Authors: YOSHIDA KEISUKE , WATANABE CHIHIRO K. , TERASHIMA ICHIRO , NOGUCHI KO
Published: June 2011

The mitochondrial alternative oxidase (AOX) has been suggested to have a beneficial role in illuminated leaves, but its function has not yet been fully elucidated. In this study, we investigated the effects of a knockout of the AOX1a gene on photosynthesis and growth under several light conditions in Arabidopsis thaliana. The AOX‐deficient aox1a mutant showed a lowered operating efficiency of photosystem II and an enhanced activity of cyclic electron transport around photosystem I (CET‐PSI) at high irradiance. To further address the physiological association of AOX with CET‐PSI, we crossed aox1a with the pgr5 mutant, which is impaired in CET‐PSI activity. In the pgr5 mutant background, AOX deficiency did not affect the apparent photosynthetic efficiency, indicating that the direct contribution of AOX to photosynthesis is not so large compared with CET‐PSI. Nevertheless, the growth of the aox1a pgr5 double mutant was significantly impaired depending on the light intensity under growth conditions. The possibility of a synergistic function of AOX with CET‐PSI in supporting plant growth is discussed.
Understanding the role of H2O2 during pea seed germination: a combined proteomic and hormone profiling approach
Authors: BARBA‐ESPÍN GREGORIO , DIAZ‐VIVANCOS PEDRO , JOB DOMINIQUE , BELGHAZI MAYA , JOB CLAUDETTE , HERNÁNDEZ JOSÉ ANTONIO
Published: June 2011

In a previous publication, we showed that the treatment of pea seeds in the presence of hydrogen peroxide (H2O2) increased germination performance as well as seedling growth. To gain insight into the mechanisms responsible for this behaviour, we have analysed the effect of treating mature pea seeds in the presence of 20 mm H2O2 on several oxidative features such as protein carbonylation, endogenous H2O2 and lipid peroxidation levels. We report that H2O2 treatment of the pea seeds increased their endogenous H2O2 content and caused carbonylation of storage proteins and of several metabolic enzymes. Under the same conditions, we also monitored the expression of two MAPK genes known to be activated by H2O2 in adult pea plants. The expression of one of them, PsMAPK2, largely increased upon pea seed imbibition in H2O2, whereas no change could be observed in expression of the other, PsMAPK3. The levels of several phytohormones such as 1‐aminocyclopropane carboxylic acid, indole‐3‐acetic acid and zeatin appeared to correlate with the measured oxidative indicators and with the expression of PsMAPK2. Globally, our results suggest a key role of H2O2 in the coordination of pea seed germination, acting as a priming factor that involves specific changes at the proteome, transcriptome and hormonal levels.
Redox regulation in plant programmed cell death
Authors: DE PINTO M. C. , LOCATO V. , DE GARA L.
Published: June 2011

Programmed cell death (PCD) is a genetically controlled process described both in eukaryotic and prokaryotic organisms. Even if it is clear that PCD occurs in plants, in response to various developmental and environmental stimuli, the signalling pathways involved in the triggering of this cell suicide remain to be characterized. In this review, the main similarities and differences in the players involved in plant and animal PCD are outlined. Particular attention is paid to the role of reactive oxygen species (ROS) as key inducers of PCD in plants. The involvement of different kinds of ROS, different sites of ROS production, as well as their interaction with other molecules, is crucial in activating PCD in response to specific stimuli. Moreover, the importance is stressed on the balance between ROS production and scavenging, in various cell compartments, for the activation of specific steps in the signalling pathways triggering this cell suicide process. The review focuses on the complexity of the interplay between ROS and antioxidant molecules and enzymes in determining the most suitable redox environment required for the occurrence of different forms of PCD.
Glycinebetaine enhances the tolerance of tomato plants to high temperature during germination of seeds and growth of seedlings
Authors: LI SHUFEN , LI FENG , WANG JIANWEI , ZHANG WEN , MENG QINGWEI , CHEN TONY H. H. , MURATA NORIO , YANG XINGHONG
Published: June 2011

Tomato (Lycopersicon esculentum cv. ‘Moneymaker’) was transformed with a codA gene, from Arthrobacter globiformis, for choline oxidase that had been modified to allow targeting to both chloroplasts and the cytosol. Glycinebetaine (GB) accumulated in seeds of transformed plants up to 1 µmol g−1 dry weight (DW), while no detectable GB was found in wild‐type (WT) seeds. The codA‐transgenic seeds germinated faster and at higher frequency than WT seeds with high temperature treatment. After heat stress, levels of expression of a mitochondrial small heat‐shock protein (MT‐sHSP), heat‐shock protein 70 (HSP70) and heat‐shock cognate 70 (HSC70) were higher in transgenic seeds than in WT seeds during heat stress, and the accumulation of HSP70 was more prominent in codA‐transgenic seeds than in WT seeds. Addition of GB to the germination medium or imbibition of seeds in a solution of GB enhanced the tolerance of WT seeds to high temperatures. WT seeds treated with exogenous GB also expressed heat‐shock genes at elevated levels and accumulated more HSP70 than controls. Our results suggest that GB, either applied exogenously or accumulated in vivo in codA‐transgenic seeds, enhanced the expression of heat‐shock genes in and improved the tolerance to high temperature of tomato seeds during germination.
An Arabidopsis (malectin‐like) leucine‐rich repeat receptor‐like kinase contributes to downy mildew disease
Authors: HOK SOPHIE , DANCHIN ETIENNE G. J. , ALLASIA VALÉRIE , PANABIÈRES FRANCK , ATTARD AGNÈS , KELLER HARALD
Published: June 2011

Biotrophic filamentous plant pathogens frequently establish intimate contact with host cells through intracellular feeding structures called haustoria. To form and maintain these structures, pathogens must avoid or suppress defence responses and reprogramme the host cell. We used Arabidopsis whole‐genome microarrays to characterize genetic programmes that are deregulated during infection by the biotrophic' oomycete downy mildew pathogen, Hyaloperonospora arabidopsidis. Marked differences were observed between early and late stages of infection, but a gene encoding a putative leucine‐rich repeat receptor‐like kinase (LRR‐RLK) was constantly up‐regulated. We investigated the evolutionary history of this gene and noticed it being one of the first to have emerged from a common ancestral gene that gave rise to a cluster of 11 genes through duplications. The encoded LRR‐RLKs harbour an extracellular malectin‐like (ML) domain in addition to a short stretch of leucine‐rich repeats, and are thus similar to proteins from the symbiosis receptor‐like kinase family. Detailed expression analysis showed that the pathogen‐responsive gene was locally expressed in cells surrounding the oomycete. A knockout mutant showed reduced downy mildew infection, but susceptibility was fully restored through complementation of the mutation, suggesting that the (ML‐)LRR‐RLK contributes to disease. According to the mutant phenotype, we denominated it Impaired Oomycete Susceptibility 1 (IOS1).
Effect of ammonium/nitrate ratio in nutrient solution on control of Fusarium wilt of tomato by Trichoderma asperellum T34
Authors: Borrero C. , Trillas M.I. , Delgado A. , Avilés M.
Published: June 2011

The behaviour of Fusarium oxysporum f.sp. lycopersici (Fol) and the effectiveness of the microbial control agent Trichoderma asperellum strain T34 were examined in hydroponically grown tomato plants under five ammonium/nitrate ratios. The results showed that disease severity was reduced by the action of T34 under increasing concentrations of ammonia. Furthermore, rhizosphere F. oxysporum populations decreased with T34 application. The presence of T34 augmented leaf nitrogen concentration in treatments infested with Fol. In addition, T34 application reduced iron concentration in tomato leaves at high ammonium/nitrate ratios and reduced the severity of Fusarium wilt at high iron and nitrogen leaf concentrations.
Comparison of disease patterns assessed by three independent surveys of cassava mosaic virus disease in Rwanda and Burundi
Authors: Bouwmeester H. , Heuvelink G. B. M. , Legg J. P. , Stoorvogel J. J.
Published: June 2011

Cassava mosaic disease (CMD) seriously affects cassava yields in Africa. This study compared the spatial distribution of CMD using three independent surveys in Rwanda and Burundi. Geostatistical techniques were used to interpolate the point‐based surveys and predict the spatial distributions of different measures of the disease. Correlative relationships were examined for 35 environmental and socio‐economic spatial variables of which 31 were correlated to CMD intensity, with the highest correlation coefficients for latitude (−0·47), altitude (−0·36) and temperature (+0·36). The most significant explanatory variables were entered in separate linear regression models for each of the surveys. The models explained 54%, 44% and 22% of the variation in CMD. The residuals of the regression models were interpolated using kriging and added to the regression models to map CMD across both countries. Significant differences were calculated in some areas after correcting for interpolation error. An important explanation of the differences is interaction between the CMD pandemic and the dates of the three surveys. Large relative prediction errors obtained in the regression kriging procedure show the need to improve the survey design and decrease measurement error. Improved maps of crop diseases such as CMD could aid targeting of control interventions and thereby contribute to increasing crop yields. This study validated the unique character of each of the survey approaches adopted and underlines the importance of specific interpretation of results for CMD management. The study emphasizes the need for optimization of sampling designs and survey protocols to maximize the potential of regression kriging.
Similar Superantigen Gene Profiles and Superantigen Activity in Norwegian Isolates of Invasive and Non‐Invasive Group A Streptococci
Authors: Michaelsen T. E. , Andreasson I. K. G. , Langerud B. K. , Caugant D. A.
Published: June 2011

Group A streptococcus (GAS) harbours several virulence factors, including M protein (coded by the emm gene) and superantigens (SAgs). SAgs are extracellular toxins that directly activate the immune system by cross‐binding to the HLA class II molecule and T cell receptor (TCR), thereby causing activation of up to 30% of the T cells and subsequent massive secretion of cytokines. Forty‐eight GAS strains isolated from patients at Norwegian hospitals between 1988 and 2004 were included in this study. Of these, 24 were invasive streptococcal toxic shock syndrome (STSS) or necrotizing fasciitis (NF) isolates and 24 were non‐invasive pharyngitis isolates, matched for having the same T‐type and year of isolation as the invasive isolates. The isolates were characterized by emm sequence typing, multilocus sequence typing (MLST) and SAg gene profiles. A correlation between T‐type, emm type, sequence type and SAg gene profile was revealed. No difference between invasive and non‐invasive isolates regarding serotype or genotype was demonstrated. Selected invasive and non‐invasive isolates with identical SAg gene profiles were analysed for SAg activity in bacterial growth culture media with and without human cell culture media added. A human T cell proliferation assay was used as measurement for SAg activity and simultaneously we also measured the cytokine content in normal human peripheral blood leucocyte cell culture media. The results revealed that invasive and non‐invasive isolates did not differ significantly in SAg activity as it is present in semipurified bacterial culture medium.
The Ammarnäs Complex in the central Scandinavian Caledonides: an allochthonous basin fragment in the foreland of the Sveconorwegian orogen?
Authors: Grimmer J. C. , Greiling R. O. , Gerdes A.
Published: June 2011

Terra Nova, 23, 270–279, 2011

The Ammarnäs Complex is a tectonic unit in the Middle Allochthon of the central Scandinavian Caledonides and consists of several hundred metres of thick uniform meta‐greywacke successions of greenschist metamorphic grade containing kilometre‐scale lenses of pre‐Caledonian crystalline basement rocks. Meta‐greywacke samples were analysed for major and trace elements and U‐Pb isotopes. Lithoclasts and geochemical data indicate that the greywackes were derived from granitic–granodioritic rocks. Detrital zircon dating yielded 7% Neoproterozoic, 52% Mesoproterozoic and 41% Palaeoproterozoic 207Pb/206Pb ages with two prominent age peaks at 1.64 and 1.5 Ga and a broad distribution of Sveconorwegian (1140–900 Ma) and ‘pre‐Sveconorwegian’ (1340–1140 Ma) ages. We interpret the Ammarnäs Complex as a former Neoproterozoic basin in the foreland of the Sveconorwegian orogen, which escaped major pre‐Caledonian magmatism–metamorphism and which was most likely deposited between c. 920 and 630 Ma.

Terra Nova, 00, 1–10, 2011
The charophycean green algae provide insights into the early origins of plant cell walls
Authors: Sørensen Iben , Pettolino Filomena A. , Bacic Antony , Ralph John , Lu Fachuang , O’Neill Malcolm A. , Fei Zhangzhun , Rose Jocelyn K. C. , Domozych David S. , Willats William G. T.
Published: June 2011

Numerous evolutionary innovations were required to enable freshwater green algae to colonize terrestrial habitats and thereby initiate the evolution of land plants (embryophytes). These adaptations probably included changes in cell‐wall composition and architecture that were to become essential for embryophyte development and radiation. However, it is not known to what extent the polymers that are characteristic of embryophyte cell walls, including pectins, hemicelluloses, glycoproteins and lignin, evolved in response to the demands of the terrestrial environment or whether they pre‐existed in their algal ancestors. Here we show that members of the advanced charophycean green algae (CGA), including the Charales, Coleochaetales and Zygnematales, but not basal CGA (Klebsormidiales and Chlorokybales), have cell walls that are comparable in several respects to the primary walls of embryophytes. Moreover, we provide both chemical and immunocytochemical evidence that selected Coleochaete species have cell walls that contain small amounts of lignin or lignin‐like polymers derived from radical coupling of hydroxycinnamyl alcohols. Thus, the ability to synthesize many of the components that characterize extant embryophyte walls evolved during divergence within CGA. Our study provides new insight into the evolutionary window during which the structurally complex walls of embryophytes originated, and the significance of the advanced CGA during these events.
Arabidopsis thaliana alpha1,2‐glucosyltransferase (ALG10) is required for efficient N‐glycosylation and leaf growth
Authors: Farid Akhlaq , Pabst Martin , Schoberer Jennifer , Altmann Friedrich , Glössl Josef , Strasser Richard
Published: June 2011

Assembly of the dolichol‐linked oligosaccharide precursor (Glc3Man9GlcNAc2) is highly conserved among eukaryotes. In contrast to yeast and mammals, little is known about the biosynthesis of dolichol‐linked oligosaccharides and the transfer to asparagine residues of nascent polypeptides in plants. To understand the biological function of these processes in plants we characterized the Arabidopsis thaliana homolog of yeast ALG10, the α1,2‐glucosyltransferase that transfers the terminal glucose residue to the lipid‐linked precursor. Expression of an Arabidopsis ALG10–GFP fusion protein in Nicotiana benthamiana leaf epidermal cells revealed a reticular distribution pattern resembling endoplasmic reticulum (ER) localization. Analysis of lipid‐linked oligosaccharides showed that Arabidopsis ALG10 can complement the yeast Δalg10 mutant strain. A homozygous Arabidopsis T‐DNA insertion mutant (alg10‐1) accumulated mainly lipid‐linked Glc2Man9GlcNAc2 and displayed a severe protein underglycosylation defect. Phenotypic analysis of alg10‐1 showed that mutant plants have altered leaf size when grown in soil. Moreover, the inactivation of ALG10 in Arabidopsis resulted in the activation of the unfolded protein response, increased salt sensitivity and suppression of the phenotype of α‐glucosidase I‐deficient plants. In summary, these data show that Arabidopsis ALG10 is an ER‐resident α1,2‐glucosyltransferase that is required for lipid‐linked oligosaccharide biosynthesis and subsequently for normal leaf development and abiotic stress response.
Corn hybrids display lower metabolite variability and complex metabolite inheritance patterns
Authors: Lisec Jan , Römisch‐Margl Lilla , Nikoloski Zoran , Piepho Hans‐Peter , Giavalisco Patrick , Selbig Joachim , Gierl Alfons , Willmitzer Lothar
Published: June 2011

We conducted a comparative analysis of the root metabolome of six parental maize inbred lines and their 14 corresponding hybrids showing fresh weight heterosis. We demonstrated that the metabolic profiles not only exhibit distinct features for each hybrid line compared with its parental lines, but also separate reciprocal hybrids. Reconstructed metabolic networks, based on robust correlations between metabolic profiles, display a higher network density in most hybrids as compared with the corresponding inbred lines. With respect to metabolite level inheritance, additive, dominant and overdominant patterns are observed with no specific overrepresentation. Despite the observed complexity of the inheritance pattern, for the majority of metabolites the variance observed in all 14 hybrids is lower compared with inbred lines. Deviations of metabolite levels from the average levels of the hybrids correlate negatively with biomass, which could be applied for developing predictors of hybrid performance based on characteristics of metabolite patterns.