bluuebunny/crossref_metadata_2025 huggingface dataset:
dupA as a risk determinant in Helicobacter pylori infection
Authors: Douraghi Masoumeh , Mohammadi Marjan , Oghalaie Akbar , Abdirad Afshin , Mohagheghi Mohammad Ali , Hosseini Mahmoud Eshagh , Zeraati Hojat , Ghasemi Amir , Esmaieli Maryam , Mohajerani Nazanin
Published: April 2008

The Helicobacter pylori duodenal ulcer promoting (dupA) gene has been previously described as a risk marker for duodenal ulcer (DU) development and a protective factor against gastric cancer (GC). Recent studies which have assessed the application of dupA in the prediction of clinical outcomes have been controversial. In the current study, the association of dupA with the clinical outcomes and histopathological changes following H. pylori infection was evaluated in Iranian patients. A total of 157 H. pylori-infected patients with DU (n=30), gastric ulcer (n=23), gastritis (n=68) or GC (n=36) were assessed. The presence of jhp0917 and jhp0918 genes was determined by gene specific PCR. Gastric histopathological changes were recorded according to the updated Sydney system. Seventy-eight (49.7 %) and 71 (45.2 %) of the 157 tested strains, respectively, were positive and negative for both genes. The remaining 8 (5.09 %) of the 157 strains were jhp0917-positive/jhp0918-negative. Univariate analysis showed inverse associations between dupA and histological features including dysplasia as the penultimate stage of GC and lymphoid follicles as a consequence of relatively long-standing H. pylori-associated gastritis. The degrees of nucleotide sequence identity of Iranian strains to Colombian, Brazilian and Indian strains ranged from 86.1 to 100 % for the aligned regions of jhp0917, from 88  to 98.8 % for jhp0918 and from 93.4  to 99.5 % for the partial sequences of the dupA gene. Despite the fact that possession of the dupA gene showed no association with any disease category in our population as reported in several other countries, association of dupA-negative strains of H. pylori with pre-malignant lesions calls for additional studies to evaluate the role of this gene as a protective marker against GC.
A case of community-acquired Acinetobacter baumannii meningitis – has the threat moved beyond the hospital?
Authors: Lowman Warren , Kalk Thomas , Menezes Colin N. , John Melanie A. , Grobusch Martin P.
Published: April 2008

Acinetobacter baumannii is a prolific nosocomial pathogen renowned for its multidrug-resistant nature. We report a case of community-acquired meningitis due to A. baumannii. The case highlights the potential pathogenicity of this organism and raises concerns that this highly adaptable organism may soon evolve into a significant community pathogen, too.
RUPTURED POLLEN GRAIN1, a Member of the MtN3/saliva Gene Family, Is Crucial for Exine Pattern Formation and Cell Integrity of Microspores in Arabidopsis
Authors: Guan Yue-Feng , Huang Xue-Yong , Zhu Jun , Gao Ju-Fang , Zhang Hong-Xia , Yang Zhong-Nan
Published: April 2008

During microsporogenesis, the microsporocyte (or microspore) plasma membrane plays multiple roles in pollen wall development, including callose secretion, primexine deposition, and exine pattern determination. However, plasma membrane proteins that participate in these processes are still not well known. Here, we report that a new gene, RUPTURED POLLEN GRAIN1 (RPG1), encodes a plasma membrane protein and is required for exine pattern formation of microspores in Arabidopsis (Arabidopsis thaliana). The rpg1 mutant exhibits severely reduced male fertility with an otherwise normal phenotype, which is largely due to the postmeiotic abortion of microspores. Scanning electron microscopy examination showed that exine pattern formation in the mutant is impaired, as sporopollenin is randomly deposited on the pollen surface. Transmission electron microscopy examination further revealed that the primexine formation of mutant microspores is aberrant at the tetrad stage, which leads to defective sporopollenin deposition on microspores and the locule wall. In addition, microspore rupture and cytoplasmic leakage were evident in the rpg1 mutant, which indicates impaired cell integrity of the mutant microspores. RPG1 encodes an MtN3/saliva family protein that is integral to the plasma membrane. In situ hybridization analysis revealed that RPG1 is strongly expressed in microsporocyte (or microspores) and tapetum during male meiosis. The possible role of RPG1 in microsporogenesis is discussed.
RDC‐assisted modeling of symmetric protein homo‐oligomers
Authors: Wang Xu , Bansal Sonal , Jiang Mei , Prestegard James H.
Published: April 2008

Protein oligomerization serves an important function in biological processes, yet solving structures of protein oligomers has always been a challenge. For solution NMR, the challenge arises both from the increased size of these systems and, in the case of homo‐oligomers, from ambiguities in assignment of intra‐ as opposed to intersubunit NOEs. In this study, we present a residual dipolar coupling (RDC)‐assisted method for constructing models of homo‐oligomers with purely rotational symmetry. Utilizing the fact that one of the principal axes of the tensor describing the alignment needed for RDC measurement is always parallel to the oligomer symmetry axis, it is possible to greatly restrict possible models for the oligomer. Here, it is shown that, if the monomer structure is known, all allowed dimer models can be constructed using a grid search algorithm and evaluated based on RDC simulations and the quality of the interface between the subunits. Using the Bacillus subtilis protein YkuJ as an example, it is shown that the evaluation criteria based on just two sets of NH RDCs are very selective and can unambiguously produce a model in good agreement with an existing X‐ray structure of YkuJ.
Side chain substitution benchmark for peptide/MHC interaction
Authors: Knapp Bernhard , Omasits Ulrich , Schreiner Wolfgang
Published: April 2008

The prediction of T‐cell epitopes is an essential part in virtual immunology. Apart from sequence‐based techniques, which achieve good results but fail to give insight into the binding behavior of a certain peptide binding to a major histocompatibility complex, structure‐based approaches are another important technique. An essential step is the correct placement of the side chains for a given peptide in cases where no experimental data for the structure are available. To our knowledge, no benchmark for side chain substitution in the area of HLA has been reported in the literature. Here, we present a comparison of five different tools (SCWRL, SCATD, SPDBV, SCit, IRECS) applicable for side chain substitution. Each tool is tested on 29 different HLA‐A2 structures with experimentally known side chain positions. Parts of the benchmark are correctness, reliability, runtime, and usability. For validation, the root mean square deviations between X‐ray structures and predicted structures are used. All tools show different strengths and weaknesses.
Clonal aspects of plant cell proliferation and their applications to animal cells and bacteria
Authors: Korn R. W.
Published: April 2008

Abstract.  Objectives: Extensive mathematical studies have been made on cell clone development but little has been advanced in the mathematics of small clone formation and virtually no actual data of small clone size has been collected. Materials and methods: Small clone sizes in leaf marginal cells of the aquatic plant Elodea and aleurone spot sizes in the grain of Zea were counted for later statistical analyses of mean, variance and probability distribution frequencies. Results: Simple mathematical models were developed and their calculated results are comparable to data collected on actual plant clones. The parameters in these models were original cell size (s0), growth rate (T), duration of growth (t) and cell division inequality (i). Conclusions: Given T and t, the critical parameter is s0. Plant tissue is ideal material to collect data on clone development because growth rate is uniform across a tissue and cells remain in place, so clone size can be measured, unlike microbes and animal cells that have neither feature. In the light of the results, traditional methods for calculating cell cycle duration and mutation rate are questioned. The applications of these plant features to studies on animal cell populations are discussed.
Applicability of cord blood‐derived unrestricted somatic stem cells in tissue engineering concepts
Authors: Degistirici Ö. , Jäger M. , Knipper A.
Published: April 2008

Abstract.  Objectives: Cell‐based tissue engineering concepts are becoming an important therapeutic alternative in the treatment of traumatic or chronic skeletal diseases. Here, we have evaluated cord blood‐derived unrestricted somatic stem cells (USSCs) for use in bone and cartilage repair strategies. Methods and results: This type of somatic stem cell can be generated from cord blood with a current rate of 29% and we have documented excellent proliferation potential to high passage numbers. The cells have an initial population doubling time of 39 h, which slightly decreased with increasing passage number, but cells maintained their proliferation abilities up to passage 23. Cells clearly differentiated towards chondrogenic, adipogenic and osteogenic lineage as shown by reverse transcription‐polymerase chain reaction as well as by histological, biochemical and immunohistochemical stains. Differentiation potential of USSCs was observed at passage 6, passage 15 and passage 21. In addition, USSCs showed increased secretion of vascular endothelial growth factor (VEGF) during osteogenic differentiation, as well as expression of key markers of angiogenesis such as vascular endothelial growth factor receptor‐2 and platelet/endothelial cell adhesion molecule. Conclusions: USSCs when transplanted into a bone defect might support the repair process not only by pure remineralization but also by installation of angiogenic environment.
Food allergy QoL questionnaire for children aged 0–12 years: content, construct, and cross‐cultural validity
Authors: DunnGalvin A. , De BlokFlokstra B. M. J. , Burks A. W. , Dubois A. E. J. , Hourihane J. O'B.
Published: April 2008

Background
To date, there is no food allergy‐specific questionnaire that allows parents to report children's health‐related QoL (HRQL) from the child's perspective.

Objective
The aim of this study was to develop a sensitive, multi‐dimensional measure to assess parental perception of HRQL in children aged 0–12 years with food allergy.

Methods
The Food Allergy QoL – Parent Form (FAQLQ‐PF) was developed and validated in four stages: (1) item generation using focus groups, expert opinion, and literature review; (2) item reduction, using clinical impact and factor analysis; (3) internal and test–retest reliability and construct validity were evaluated using relevant scales of the Child Health Questionnaire (CHQ)‐28 and the disease‐specific food allergy independent measure (FAIM); and (4) cross‐cultural and content validity was examined by administering the questionnaire in a US sample.

Results
Stage 1: Saturation was reached at 110 items.

Stage 2: The reduced instrument has 14 items for children <4 years and 26 and 30 items for children aged 4–6 years and 7–12 years, respectively. Factor analysis revealed three subscales: emotional impact, food anxiety, and social and dietary limitations, accounting for 68% of the variance.

Stage 3: Cronbach's α >0.7 for subscales and total score. Construct validity was demonstrated by significant correlations between relevant scales of the CHQ‐28 and FAQLQ‐PF subscales (r=0.69–0.77, P<0.01), and between FAQLQ‐PF subscales and the FAIM. Sensitivity was shown by significant within‐group differences in a sample of 124 food‐allergic children.

Stage 4: The FAQLQ‐PF was validated in a sample of US children, Cronbach's α >0.7 for subscales and total score. Construct validity was demonstrated by significant correlations between FAQLQ‐PF and the FAIM (parent report) and between the FAQLQ‐PF and the FAIM (child report). No differences were observed between the US and Irish scores.

Conclusion
The FAQLQ‐PF is psychometrically robust, with excellent reliability and validity.
Patients cured from craniopharyngioma or nonfunctioning pituitary macroadenoma (NFMA) suffer similarly from increased daytime somnolence despite normal sleep patterns compared to healthy controls
Authors: Van Der Klaauw Agatha A. , Biermasz Nienke R. , Pereira Alberto M. , Van Kralingen Klaas W. , Dekkers Olaf M. , Rabe Klaus F. , Smit Johannes W. A. , Romijn Johannes A.
Published: April 2008

Objective  Adults patients previously treated for craniopharyngioma have increased general and physical fatigue compared to healthy controls. This could be related to disturbed sleep patterns. The aim of this study was to compare sleepiness and sleep patterns in those patients to healthy controls and to patients treated for nonfunctioning macroadenomas (NFMA) of the pituitary.

Design  Case‐control study.

Patients and methods  Sleepiness and sleep patterns were assessed in 27 adult patients [14 men, 8 patients diagnosed at childhood age, mean age of 53 years (range 27–80 year)] after long‐term follow‐up and compared to 50 healthy controls and 38 age‐, gender‐ and BMI‐matched patients with NFMA. We used two validated questionnaires for sleep parameters (Epworth sleepiness score and Münchener Chronotype Questionnaire).

Results  Sleep patterns (onset, sleep timing, duration and rise time) were not statistically different between the three groups. However, daytime sleepiness scores were increased in patients treated for craniopharyngioma compared to healthy controls, but not different from patients with NFMA. Thirty‐three percent of patients with craniopharyngiomas had ESS scores above 10 compared to 8% of healthy controls (P = 0·005), indicating severe daytime hypersomnolence. Neither type of surgery, previous radiotherapy, or age at diagnosis influenced the sleepiness scores in patients with craniopharyngioma.

Conclusion  Patients treated for craniopharyngioma or NFMA have increased daytime somnolence despite normal sleep patterns, compared to healthy subjects. The results indicate that increased daytime somnolence is a general consequence of large tumours, and/or their treatment, in the hypothalamic/pituitary region, rather than a specific feature of craniopharyngiomas per se.
Immunohistochemical localization of nanog and Oct4 in stem cell compartments of human sacrococcygeal teratomas
Authors: Busch C , Oppitz M , Wehrmann M , Schweizer P , Drews U
Published: April 2008

Aims:  To study the range of differentiation and presence of cells positive for stem cell markers in 20 sacrococcygeal teratomas (SCTs) which were consecutively operated on between 1990 and 2000 in the Department of Paediatric Surgery in Tübingen, Germany.

Methods and results:  Preserved paraffin‐embedded material was re‐evaluated. In addition to tissues of various organs, caudal organ structures not described before were identified, such as colon with pancreas originating from colonic crypts, Fallopian tube and vaginal epithelia. The derivation of the latter was confirmed by Müllerian duct specific CA125 and CA19‐9 antibodies. The expression of stem cell markers was studied with antibodies against nanog, Oct4, SSEA‐4, nestin and subtype M3 muscarinic receptors. Cells positive for these markers were encountered in immature end buds and capillary sprouts, and as single cells in neural tissue, gonadal structures, hairs and in the stem cell niches of differentiated epithelia.

Conclusions:  Our data indicate that SCTs of the newborn arise from remnants of the epiblast‐like tail bud blastema and demonstrate that they contain cells positive for embryonic stem cell markers and may represent a novel source for human embryonic stem cells.
Prostaglandin E2 and Krüppel‐like transcription factors synergistically induce the expression of decay‐accelerating factor in intestinal epithelial cells
Authors: Shao Jinyi , Yang Vincent W. , Sheng Hongmiao
Published: April 2008

The decay‐accelerating factor (DAF) prevents the intestinal mucosa from bystander killing by complement. Prostaglandin E2 (PGE2) induces the expression of DAF that may protect the tumour environment from complement attack. In the present study, we demonstrate synergistic actions of PGE2 and two Krüppel‐like factors (KLFs), which are zinc finger‐containing transcription factors, in DAF regulation. Overexpression of KLF4 and KLF5 robustly induced transcriptional activity of the DAF promoter. In combination, PGE2 and either KLF4 or KLF5 increased the expression of DAF in a synergistic fashion. Moreover, cyclooxygenase (COX‐1 and COX‐2) enzymes, KLF4/5 and DAF protein were coordinately expressed in normal intestinal mucosa as well as in intestinal neoplasm. In radiation‐injured mouse intestine, COX‐1 was rapidly induced and remained at relatively high levels. While KLF5 was quickly elevated after irradiation, KLF4 exhibited a delayed increase. Interestingly, levels of DAF increased gradually following the induction of COX‐1 and KLFs. Mimicking the circumstances in vivo, coexpression of both COX and KLFs resulted in a synergistic or additive induction of DAF transcription in intestinal epithelial cells. Our data suggest that COX‐derived PGE2 may collaborate with KLF4/5 to regulate the activation of the complement system and exert diverse effects on the intestinal epithelium.
Serum concentrations of CCR4 ligands in relation to clinical severity of atopic dermatitis in Egyptian children
Authors: Mostafa Gehan Ahmed , Tomoum Hoda Yahya , Salem Samar Abd Allah , Abd El‐Aziz Manal Mohamed , Abou El‐Maged Doaa Ibrahim , El‐Sayed El‐Far Ibrahim
Published: April 2008

T helper 2 (Th2) lymphocytes, the key effector cells in pathogenesis of atopic dermatitis (AD), express CCR4 receptors. CCR4 ligands (macrophage‐derived chemokine ‘MDC’ and thymus and activation‐regulated chemokine ‘TARC’) direct trafficking and recruitment of Th2 cells into lesional skin in AD. These chemokines appear to be useful inflammatory markers for assessing severity of AD in adults. However, the same results have not been replicated in children. Therefore, we were stimulated to elucidate the expression of CCR4 ligands in children with AD and their relation to clinical disease severity. To investigate this, serum concentrations of CCR4 ligands were determined in 60 children, of whom 30 had AD and 30 were healthy matched subjects. Patients were classified into mild (n = 8), moderate (n = 12) and severe (n = 10) according to the objective scoring AD (obj‐SCORAD) index. Serum concentrations of MDC and TARC were significantly increased in children with AD (2697 ± 982.6 pg/ml and 945.5 ± 494.7 pg/ml, respectively) compared with controls (357.2 ± 233.2 pg/ml and 214.2 ± 116.6 pg/ml, respectively, p < 0.0001). Serum levels of both chemokines went hand in hand with disease severity as they were significantly higher in severe than moderate and in moderate than mild AD. In addition, they correlated positively with obj‐SCORAD (r = 0.99 for both, p < 0.0001). Furthermore, both chemokines had significant positive correlations to blood eosinophil counts and serum immunoglobulin E. In conclusion, serum CCR4 ligands may be useful inflammatory markers for assessing AD severity in children. Further studies may pave way for CCR4 ligands antagonism among the adjuvant therapeutic strategies of AD.
Association of mast cells and liver allograft rejection
Authors: Arikan Cigdem , Nart Deniz , Kilic Murat , Yuksekkaya Hasan Ali , Aydogdu Sema
Published: April 2008

Abstract:  MCs are important effector cells in a broad range of immune responses. Their role in liver allograft rejection is not clear. Twenty‐one liver transplant recipients (mean age ± s.d.; 10.2 ± 4.1 yr) who experienced a rejection episode are included in this study. Biopsy specimens from normal livers (allograft biopsy with normal histopathology n = 5 and naïve livers n = 6), transplanted livers with CR (n = 5), and transplanted livers with ACR (n = 26) were studied. The total number of PT in each biopsy specimen was documented, and the number of PT that contained MCs was expressed as a percentage of the total number of PT. MCs, percentage of PT containing MCs and the average number of MCs/PT was significantly higher in rejection specimens than in control biopsy samples. All parameters were significantly higher in CR group than AR groups. Increasing grades of rejection was also associated with progressively more MCs and MC/PT (r = 0.68 p = 0.000; r = 0.58 p = 0.002). Only serum bilirubin level was related to the MCs in AR group. Only MC/PT was detected as an independent predictor of graft survival (p = 0.011, RR 2.87 95% CI 1.3–6.5). Despite the fact that the role of MCs in liver allograft rejection is still unknown; they exist in inflammatory infiltrates during pediatric liver allograft rejection. MC‐rich portal infiltrates may distinguish chronic liver rejection from other inflammatory states such as AR, hepatitis and biliary obstruction.
Cardiac retransplantation in children
Authors: Mahle William T.
Published: April 2008

Abstract:  To discuss the indications for and outcomes of cardiac retransplantation in childhood. The major challenge of pediatric heart transplantation is graft failure. The major causes of graft failure include coronary allograft vasculopathy and chronic rejection. Retransplantation may be considered in children or young adults who develop graft failure following pediatric heart transplantation. Retransplantation now accounts for 7% of all pediatric transplants. Recent studies have demonstrated that cardiac retransplantation has a poorer outcome than primary heart transplantation. However, the interval from primary transplant to retransplantation appears to impact significantly the success of retransplantation. When children undergo retransplantation for early graft failure, the survival is quite poor and the appropriateness of this strategy is questionable. However, children who undergo retransplantation many years after primary transplantation have outcomes that are similar to primary transplantation. The decision to pursue retransplantation depends on the severity of graft failure and recent data suggest that identification of mild graft dysfunction or coronary allograft vasculopathy does not imply impending graft failure. Novel therapies to extend the life of the primary graft and to stratify those at risk of severe graft dysfunction will improve the allocation of scarce organs for pediatric patients who might be candidates for cardiac retransplantation. Retransplantation can extend the lives of children who develop graft failure after primary transplantation. However, not all patients who develop graft dysfunction should necessarily be listed for retransplantation.
Effects of progressive drought stress on the expression of patatin‐like lipid acyl hydrolase genes in Arabidopsis leaves
Authors: Matos Ana Rita , Gigon Agnès , Laffray Daniel , Pêtres Stéphane , Zuily‐Fodil Yasmine , Pham‐Thi Anh‐Thu
Published: April 2008

Patatin‐like genes have recently been cloned from several plant species and found to be involved in stress responses and development. In previous work, we have shown that a patatin‐like gene encoding a galactolipid acyl hydrolase (EC 3.1.1.26) was stimulated by drought in the leaves of the tropical legume, Vigna unguiculata L. Walp. The aim of the present work was to study the expression of patatin‐like genes in Arabidopsis thaliana under water deficit. Expression of six genes was studied by reverse transcriptase polymerase chain reaction in leaves of plants submitted to progressive drought stress induced by withholding water and also in different plant organs. Three genes, designated AtPAT IIA, AtPAT IVC and AtPAT IIIA, were shown to be upregulated by water deficit but with different kinetics, while the other patatin‐like genes were either constitutive or not expressed in leaves. The accumulation of transcripts of AtPAT IIA in the early stages of the drought treatment was coordinated with the upregulation of lipoxygenase and allene oxide synthase genes. AtPAT IIA expression was also induced by wounding and methyl jasmonate treatments. The in vitro lipolytic activity toward monogalactosyldiacylglycerol, digalactosyldiacylglycerol, phosphatidylcholine and phosphatidylglycerol was confirmed by producing the recombinant protein ATPAT IIA in insect cells. The analysis of free fatty acid pools in drought‐stressed leaves shows an increase in the relative amounts of trans‐3‐hexadecenoic acid at the beginning of the treatment followed by a progressive accumulation of linoleic and linolenic acids. The possible roles of AtPAT IIA in lipid signaling and membrane degradation under water deficit are discussed.
Colour variation in female common lizards: why we should speak of morphs, a reply to Cote et al.
Authors: VERCKEN E. , SINERVO B. , CLOBERT J.
Published: April 2008

Female common lizards display variation in their ventral colour, ranging from pale yellow to bright orange. In a previous study, we proposed a discrete classification of this variation into three colour classes: yellow, orange and mixed. However, a recent study reported on continuity of reflectance spectra and plastic change in spectrum components in female common lizards, which made the authors question the validity of a discrete classification of colour patterns in this species. Here, we discuss the relevance of discrete, eye‐based colour classification for understanding the ecological processes that shape the social structure of common lizard female populations. First, as the mixed colour class is characterized by heterogeneous distribution of colour, we explain that it cannot be reliably described by localized spectrophotometer measurements. On the contrary, the classification of colour into three discrete classes is consistent with the description of three alternative strategies in female common lizards. Then, although we support the ecological importance of colour plasticity in this species, we refute the hypothesis of a condition‐dependent signal, which is not supported by experimental data. At last, we explain that colour plasticity, and in particular hormone‐mediated plasticity is compatible with genetic inheritance of colour and the evolution of alternative strategies. Indeed, the genetic background and the environment, especially the social environment, are expected to interact adaptively to modulate the expression of colour signals and alternative strategies.
Kell alloimmunization in pregnancy: associated with fetal thrombocytopenia?
Authors: Van Den Akker E. S. A. , Klumper F. J. C. M. , Brand A. , Kanhai H. H. H. , Oepkes D.
Published: April 2008

Background and Objectives  Kell haemolytic disease in pregnancies has been suggested to be associated with decreased fetal platelet counts. The aim of this study was to evaluate the incidence and clinical significance of fetal thrombocytopenia in pregnancies complicated by Kell alloimmunization.

Materials and Methods  In this retrospective cohort study, fetal platelet counts were performed in 42 pregnancies with severe Kell alloimmunization prior to the first intrauterine blood transfusion. Platelet counts from 318 first intrauterine transfusions in RhD alloimmunized pregnancies were used as controls.

Results  Fetal thrombocytopenia (platelet count < 150 × 109/l) was found in 4/42 (10%) in the Kell group and in 84/318 (26%) in the RhD group. None of the fetuses in the Kell alloimmunized pregnancies, including 15 with severe hydrops, had a clinically significant thrombocytopenia defined as a platelet count < 50 × 109/l. In the RhD alloimmunized pregnancies, 2/230 (1%) of the non‐hydropic fetuses and 7/30 (23%) of the severely hydropic fetuses had a clinically significant thrombocytopenia.

Conclusion  In contrast to fetuses with severe anaemia and hydrops due to RhD alloimmunization, fetuses with severe anaemia due to Kell alloimmunization are generally not at risk for substantial thrombocytopenia.
Rearing method and life‐table data for the cocoa mirid bug Sahlbergella singularis Haglund (Hemiptera: Miridae)
Authors: Babin R. , Bisseleua D. H. B. , Dibog L. , Lumaret J. P.
Published: April 2008

The mirid bug Sahlbergella singularis feeds on cocoa pods and shoots, causing considerable crop losses. As laboratory experimentation requires numerous insects, this study aimed at improving available rearing method of S. singularis for Cameroon. Fifty second to fifth nymphal stages were collected at a cocoa farm and reared to the adult stage on cocoa pods in an insectary (T = 24.7 ± 0.9°C, RH = 84.5 ± 6.8%, photoperiod: 12 : 12 L : D). Newly emerged females were confined for 5–6 days on cocoa twigs for sexual maturation and each female paired with a male for 24 h. The pairs were returned to the field and enclosed in mousseline sleeves on attached cocoa pods, for egg laying. After 16 days (expected egg lifetime), the sleeve cages were checked daily to detect newly hatched nymphs. Then, the pods were collected and brought to the insectary, where nymphs continued to emerge and develop into adults. Our method allowed the production of 14.6 ± 6.7 nymphs per female per generation, for 15 consecutive generations. Nymphal survival was calculated to be 68.2% and the mean duration of the nymphal development was measured at 22.7 ± 3.1 days. The rearing performance was evaluated using life‐table calculations. The net reproductive rate (R0) was 6.59; the intrinsic rate of increase (r) was 0.037 per female per day with a population doubling time (Td) of 18.9 days. On average each female contributed 9.70 individuals to the population given a mean generation time (Tc) of 52.1 days. The percentage of reproductive females and the mean number of nymphs per female were significantly different between generations, with 86.8% and 18.1% in generation G7 as compared to 45.8% and 8.4% for generation G5, respectively. As rainfall showed concordant variations during the period of investigation, we discuss the impact of this factor on mirid fecundity.
Comparative assessment of the efficacy of entomopathogenic nematode species at reducing western corn rootworm larvae and root damage in maize
Authors: Toepfer S. , Peters A. , Ehlers R.‐U. , Kuhlmann U.
Published: April 2008

The western corn rootworm (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) is an invasive maize (Zea mays L.) pest in Europe. Crop yield is significantly impacted by the feeding of all three larval instars on maize roots, making them prime targets for control measures. Therefore, the control efficacy of three entomopathogenic nematodes (EPNs), Steinernema feltiae (Filipjev), Heterorhabditis bacteriophora Poinar, and H. megidis Poinar, Jackson and Klein (Nematoda: Rhabditida), was studied in four field plot experiments in southern Hungary in 2005 and 2006. All EPN species significantly reduced D. v. virgifera independently, whether applied as a row spray with a solid stream into the soil at sowing or onto the soil along maize rows in June. When applied at maize sowing, H. bacteriophora was more effective at reducing D. v. virgifera (81%) than H. megidis (49%) and S. feltiae (36%). When applied in June, H. bacteriophora and H. megidis were more effective at reducing D. v. virgifera (around 70%) than S. feltiae (32%). All tested EPN species significantly reduced damage on maize roots independently, whether they were applied at sowing or in June. Damage, however, was not totally prevented. The use of H. bacteriophora for the development of a biological control product for inundative releases against D. v. virgifera larvae is suggested.
Potential positive effect of the ant species Lasius niger on linyphiid spiders
Authors: Schuch S. , Platner C. , Sanders D.
Published: April 2008

Ants are highly abundant generalist predators and important ecosystem engineers which can strongly affect the composition of animal communities. We manipulated the density of the ant species Lasius niger with baits in a small‐scale field experiment to study the role of intraguild predation, top‐down control and bottom‐up effects of ants in a dry grassland surrounded by agricultural fields. Two different kinds of baits (honey and tuna) were presented near to the nests and at a distance of 2 m from six L. niger colonies in a dry grassland habitat, where L. niger was a highly abundant, omnipresent species. The experiments were performed for 1 month in spring. Additionally, the natural abundance of L. niger varying with the distance to their nests was used to study the effects on spiders and potential prey groups. The activity of L. niger was significantly higher at tuna baits compared with that at honey baits and empty control dishes. We found no effects of higher activity of L. niger on the arthropod community. However, there is evidence for a facilitation effect of ants on Collembola near to their colonies, probably due to habitat modification, which also influenced the density of Linyphiidae. Both groups had up to four times higher denisities next to L. niger colonies than at a distance of 2 m. Furthermore, δ13C values demonstrated that linyphiid spiders and L. niger predominantly feed on Collembola. We conclude that there is no evidence of top‐down effects of L. niger in a grassland in spring, but we found a facilitation of linyphiid spiders and their prey by the ants, which acted as ecosystem engineers.
Potential Biofumigation Effects of Brassica oleracea var. caulorapa on Growth of Fungi
Authors: Fan C. M. , Xiong G. R. , Qi P. , Ji G. H. , He Y. Q.
Published: April 2008

Biofumigation, as an environment‐friendly alternative to methyl bromide is gaining attention in sustainable agricultural production systems. Based on the biofumigation suppression of growth of three soil‐borne filamentous fungi (Fusarium sp., F. oxysporum and P. aphanidermatum), Brassica oleracea var. caulorapa was selected from eight Brassica and other plant species as a potential material for the purpose. Powdered tissues of plants were confined to individual Petri dishes without physical contact with each of the following 28 fungal isolates from 16 hosts: 13 Fusarium spp., two Verticillium dahliae, two Ceratocystis fimbriata, Bipolaris sorokiniana, Gaeumannomyces graminis, Ceratobasidium cornigerum, Rhizotonia cerealis, Phytophthora parasitica, Phytophthora capsici, Botrytis cinerea, two Rhizoctonia solani, Sclerotinia sclerotiorum and Magnaporthe grisea. The level of suppression of growth 7 days after inoculation varied. Based on growth suppression, the 28 isolates were grouped into three clusters by Fuzzy clustering: Cluster I contains F. proliferatum with 20.5% suppression, Cluster II composed of 15 isolates, Fusarium sp., two V. dahliae, two C. fimbriata, B. sorokiniana, C. cornigerum, two R. solani, R. cerealis, S. sclerotiorum, P. parasitica and M. grisea, with 75.2–100% suppression and Cluster III consisted of 12 isolates; five F. oxysporum, F. solani, F. azysporum, F. moniliforme, F. graminearum, F. verticillioides, G. graminis, P. capsici with 40.7–66.2% suppression. Ceratobasidium fimbriata and V. dahliae were more sensitive to biofumigation than S. sclerotiorum and F. culmorum when different amounts of ground powder were used. One gram of powder could suppress the growth of the former two up to 68.6% and 68.7%, but the growth suppression in the latter two by 12.7% and 24.0%, respectively. These results indicated that the amount of plant tissue to be used should be considered depending on target pathogen species. The swollen root of B. oleracea var. botrytis appeared a better material than the leaf for achieving suppression of growth in pathogenic fungi.
Molecular Characterization of Aster Yellows Phytoplasma Associated with Valerian and Sowthistle Plants by PCR–RFLP Analyses
Authors: Khadhair A.‐H. , Hiruki C. , Deyholos M.
Published: April 2008

In Alberta, Canada, valerian grown for medicinal purposes and sowthistle, a common weed, showed typical aster yellows symptoms. Molecular diagnosis was made using a universal primer pair (P1 / P7) designed to amplify the entire 16S rRNA gene and the 16 / 23S intergenic spacer region in a direct polymerase chain reaction (PCR) assay. This primer pair amplified the DNA samples from valerian and sowthistle and reference controls (AY‐27, CP, PWB, AY of canola, LWB). They produced the expected PCR products of 1.8 kb, which were diluted and used as templates in a nested PCR. Two primer pairs R16F2n / R2 and P3 / P7 amplified the DNA templates giving PCR products of 1.2 and 0.32 kb, respectively. No PCR product was obtained with either set of primers and DNA isolated from healthy plants. Restriction fragment length polymorphism (RFLP) was used to analyse the partial 16S rDNA sequences (1.2 kb) of all phytoplasma DNA samples after restriction with four endonucleases (AluI, HhaI, MseI and RsaI). The restriction patterns of these strains were found to be identical with the RFLP pattern of the AY phytoplasma reference control (AY‐27 strain). Based on the RFLP data, the two strains are members of subgroup A of the AY 16Sr1 group. We report here the first molecular study on the association of AY phytoplasmas with valerian and sowthistle plants.
Comparison of Resistance to Cotton Leaf Curl Disease (Multan/Burewala) in Gossypium hirsutum L. Varieties and Breeding Lines
Authors: Akhtar K. P. , Jamil F. F. , Haq M. A. , Khan I. A.
Published: April 2008

Twenty‐four cotton varieties and advance breeding lines were evaluated for their resistance to cotton leaf curl disease (CLCuD; Multan/Burewala) under natural field and in glasshouse conditions for two consecutive years. Resistance was based on symptom expression and disease severity index. All the cotton genotypes exposed to the vector whitefly in the field and artificially infected by grafting manifested a high level of resistance against CLCuD (Multan) with the exception of genotype NIAB‐999 that was moderately resistant. All the test varieties/breeding lines were highly susceptible to CLCuD (Burewala) both in the field and the glasshouse. However, substantial differences were noted between genotypes for disease index under field conditions. Graft inoculation studies showed that all genotypes inoculated with CLCuD (Burewala) developed disease within 9–13 days whereas those graft‐inoculated with CLCuD (Multan) developed symptoms from 15 to 22 days after grafting. Severe reduction occurred in plant morphology, fibre and yield parameters of cotton variety NIAB‐111 following inoculation with CLCuD (Burewala) as compared with CLCuD (Multan).
Ultrastructure and dispersal potential of sponge larvae: tufted versus evenly ciliated parenchymellae
Authors: Uriz Maria J. , Turon Xavier , Mariani Simone
Published: April 2008

In this work we analyse the ultrastructure and behaviour of two representative types of parenchymella sponge larvae: the evenly ciliated larva of Scopalina lophyropoda, and the tufted larva of Cacospongia mollior. We sought to find correlates of the dispersal abilities and distribution patterns of these species. Laboratory experiments were performed under two different conditions of water movement (still water and a slight oscillatory movement), and at different times of the larval life‐span. Larvae of S. lophyropoda were motionless most of the time, maintaining a vertical posture and rotating on their main axis, and they did not respond to directional light. Larvae of C. mollior were active swimmers that responded negatively to light stimuli. In both cases, movement decreased as the larval age increased. Ultrastructurally, C. mollior larvae were more compact, with more reserves and abundant collagen bundles. Desmosome‐like structures were seen connecting the apical parts of the ciliated surface in both species. Two different types of putative light‐sensitive structures were found. Both structural and behavioural characteristics favour a greater dispersal capability for C. mollior and a philopatric dispersal mode for S. lophyropoda. These predictions are in agreement with the observed ecological distribution of the species.
QTL mapping of nutrient components in maize kernels under low nitrogen conditions
Authors: Liu Z. H. , Xie H. L. , Tian G. W. , Chen S. J. , Wang C. L. , Hu Y. M. , Tang J. H.
Published: April 2008

A set of 213 F2:3 families were used to investigate the effects of nitrogen (N) on grain yield and the concentrations of three nutrient components in maize (Zea mays L.) kernels. A genetic linkage map was constructed using 189 SSR (simple sequence repeat) markers, spanning a total of 2003 cM, including 11 linkages, and the families were evaluated under high N and low N conditions at two farm locations. The results indicate that low N conditions may induce an increase in starch concentration, but a decrease in protein levels. Twenty‐six quantitative trait loci (QTL) were detected for four measured traits in the two N treatments at both locations, including eight QTL for grain yield, seven QTL for oil content, six QTL for protein content and five QTL for starch content. The total number of QTL detected for the four measured traits under high N levels was greater than the QTL detected under low N conditions, and several QTL were identified that specifically expressed under different N conditions. These particular QTL could help provide greater understanding of the genetic basis of N‐usage efficiency.
38–48 kDa subunits of buckwheat 13S globulins are controlled by a single locus
Authors: Luthar Z. , Rogl S. , Kump B. , Javornik B.
Published: April 2008

The inheritance of buckwheat (Fagopyrum esculentum Moench) seed storage proteins was investigated by control crosses between accessions containing different SDS‐PAGE protein patterns in the range of 38–48 kDa. Analysis of segregation of individual F1 and F2 seeds obtained by 17 crosses showed segregation of eight electrophoretic bands, from which 12‐banding variants were inferred. Two variants contained one band, nine contained two bands and one variant contained three bands and behaved as a single co‐dominant unit. The segregation of banding variants fits the expected ratios and thus supports the hypothesis of single Mendelian gene inheritance and that alleles are co‐dominant. The results therefore suggest that the genes controlling globulin subunits are tightly linked and inherited as a single locus. The locus was designated Glob‐1 and the twelve segregated protein variants as alleles a‐l. This is the first buckwheat globulin locus identified with multiple alleles, phenotypically expressed as groups of protein bands and thus applicable as a functional marker in buckwheat genomic studies.
Phenotypic selection for high resistance to Fusarium head blight after introgression of quantitative trait loci (QTL) from exotic spring wheat and verification by simple sequence repeat markers a posteriori
Authors: Miedaner T. , Wilde F. , Korzun V. , Ebmeyer E.
Published: April 2008

Fusarium head blight (FHB) has become an important disease of wheat. We introgressed three resistance quantitative trait loci (QTL) alleles on chromosomes 3B, 5A (from CM82036) and 3A (from ‘Frontana’) into European elite spring wheat and performed phenotypic selection among double‐cross (DC) derived progeny in generations DCF2 and DCF3. After recombination and selfing, we analysed 135 phenotypically selected progeny by simple sequence repeat (SSR) markers linked to the QTL. In a second experiment, we forwarded the best 20 progeny for a further two generations by pedigree selection. Progeny were inoculated at two to four locations with Fusarium culmorum and the percentage of infected spikelets per plot was estimated. Both experiments show that phenotypic selection was highly effective. One‐hundred out of 135 phenotypically selected DCF1:3 progeny had the combination of donor‐QTL alleles (3B + 5A + 3A, 3B + 5A) with the highest effects on FHB resistance. In the subsequent generations, sufficient genotypic variance was detected. The best F5:7 bulks had similar resistance to the donor CM82036. The FHB rating was reduced in total by 45% points compared to the parental mean. QTL with high effects can be detected solely by phenotypic selection after targeted introgression.
Investigation of bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China
Authors: Wang Li , Pan Qingshan , Zhang Libo , Xue Qin , Cui Jun , Qi Changming
Published: April 2008

Objective  To determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The effect of breed, sex and age of dogs and season on the presence or absence of bacteria in the conjunctival sac of clinically normal dogs was evaluated.

Sample population  This investigation included 240 healthy dogs, 27 dogs with unilateral corneal ulcer and one dog with bilateral corneal ulcer.

Procedure  The 480 samples from healthy dogs and the 29 samples from dogs with ulcerative keratitis were incubated in an aerobic and 5% CO2 environment at 37 °C for 48 h. Logistic regression analysis was performed. Statistical significance was set at P < 0.01.

Results  Of 480 normal eyes, Staphylococcus spp. were the most frequently isolated organisms (40.29%). Neisseria spp. (11.47%) were the next most frequently isolated organisms, followed by Corynebacterium spp. (9.4%). Of 29 eyes with ulcerative keratitis, Staphylococcus spp. were also the most frequently isolated bacteria (47.06%). Streptococcus spp. (12.94%) and Pseudomonas spp. (8.24%) were the second and third, respectively. Season (P = 0.002) was a significant factor influencing presence or absence of bacterial microorganisms in the conjunctival sac of normal dogs in Beijing, China, while the effects of breed (P = 0.095), sex (P = 0.588) and age (P = 0.866) of dogs were insignificant.

Conclusion  Staphylococcus spp. were the most frequently isolated organisms, and S. intermedius predominated in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The likelihood of detecting bacteria depends on the season.
Experimental determination and allometric prediction of vitreous volume, and retina and lens weights in Göttingen minipigs
Authors: Shafiee Afshin , McIntire Greg L. , Sidebotham Lisa C. , Ward Keith W.
Published: April 2008

Objectives  To determine the vitreous volume, and retinal and lens wet weights in male and female Göttingen minipigs of different age groups.

Procedures  Vitreous, lens and retina were isolated from fresh minipig eyes. Vitreous volume, lens and retina weight were measured and allometric scaling was utilized to predict these parameters.

Results  There were no gender differences in body weights or retina and lens weights in the three age groups examined in this study. For vitreous volumes, females had a significantly larger volume (approximately 10%–12%) than males in the 4–6 and 6–8 month, but not in the 8–11‐month group. The mean body weight increased from 12.2 ± 2.6 kg (4–6 months) to 19.4 ± 4.0 kg (8–11 months). In the same period, the mean vitreous volume increased from 2.00 ± 0.28 to 2.67 ± 0.31 mL, while the mean retinal and lens weights increased from 114 ± 22 to 126 ± 17 mg, and from 298 ± 26 to 392 ± 15 mg, respectively. Allometric analysis between six species for vitreous volume and four species for lens weight covering a weight range of 260‐fold was not able to estimate the vitreous volume, but it did predict the lens weight in 8–11 months minipigs.

Conclusions  Overall these measurements add important context to intraocular pharmacology studies, and will help in the improved design and interpretation of such experiments.