bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inheritance in tetraploid yeast revisited: segregation patterns and statistical power under different inheritance models
Authors: STIFT M. , REEVE R. , Van TIENDEREN P. H. 
Published: May 2010

AbstractIn their recent article, Albertin et al. (2009) suggest an autotetraploid origin of 10 tetraploid strains of baker’s yeast (Saccharomyces cerevisiae), supported by the frequent observation of double reduction meiospores. However, the presented inheritance results were puzzling and seemed to contradict the authors’ interpretation that segregation ratios support a tetrasomic model of inheritance. Here, we provide an overview of the expected segregation ratios at the tetrad and meiospore level given scenarios of strict disomic and tetrasomic inheritance, for cases with and without recombination between locus and centromere. We also use a power analysis to derive adequate sample sizes to distinguish alternative models. Closer inspection of the Albertin et al. data reveals that strict disomy can be rejected in most cases. However, disomic inheritance with strong but imperfect preferential pairing could not be excluded with the sample sizes used. The possibility of tetrad analysis in tetraploid yeast offers a valuable opportunity to improve our understanding of meiosis and inheritance of tetraploids.
Measuring sexual selection on females in sex‐role‐reversed Mormon crickets (Anabrus simplex, Orthoptera: Tettigoniidae)
Authors: ROBSON L. J. , GWYNNE D. T. 
Published: May 2010

AbstractAlthough many studies examine the form of sexual selection in males, studies characterizing this selection in females remain sparse. Sexual selection on females is predicted for sex‐role‐reversed Mormon crickets, Anabrus simplex, where males are choosy of mates and nutrient‐deprived females compete for matings and nutritious nuptial gifts. We used selection analyses to describe the strength and form of sexual selection on female morphology. There was no positive linear sexual selection on the female body size traits predicted to be associated with male preferences and female competition. Instead, we detected selection for decreasing head width and mandible length, with stabilizing selection as the dominant form of nonlinear selection. Additionally, we tested the validity of a commonly used instantaneous measure of mating success by comparing selection results with those determined using cumulative mating rate. The two fitness measures yielded similar patterns of selection, supporting the common sampling method comparing mated and unmated fractions.
Trafficking, lateral mobility and segregation of the plant K+ channel KAT1*
Authors: Reuff M. , Mikosch M. , Homann U. 
Published: May 2010

AbstractFunctioning of ion channels depends not only on the control of their activity but also on their density and lateral organisation in the membrane. The two latter aspects have recently attracted increasing attention. Here, we summarize studies on trafficking and plasma membrane distribution of the plant K+ channel KAT1 from Arabidopsis thaliana. In guard cells, KAT1 was found to be subject to constitutive and pressure‐driven turnover and ABA‐stimulated endocytosis. These results point to a role of exo‐ and endocytosis in regulating KAT1 density and thus ion transport during guard cell functioning. Recent studies indicate that KAT1 density can also be adjusted at the site of ER export. Efficient ER export of KAT1 was shown to depend on an acidic motif that interacts with Sec24, a component of ER‐derived vesicles. Surface expression of ER export mutants of KAT1 can be rescued through heterotetrameric assembly with wild‐type KAT1, implying that not all subunits of the channel tetramer need to carry an ER export motif. Analysis of the distribution of KAT1 in the plasma membrane revealed segregation of the channel into microdomains, and low lateral mobility in both plant and mammalian cells. In plant cells, SNAREs have been shown to be involved in anchoring KAT1 in the plasma membrane. Studies on guard cells imply a role for the cell wall in organisation of KAT1 microdomains. Together, these findings underline the importance of investigating mechanisms of KAT1 trafficking and lateral organisation in order to fully understand channel functioning.
Male Age and Experience Increases Mating Success but Not Female Fitness in the Mexican Fruit Fly
Authors: Pérez‐Staples Diana , Martínez‐Hernández María G. , Aluja Martín 
Published: May 2010

AbstractMale age and sexual experience are important condition parameters that can influence mate choice and female fitness, yet they are seldom studied simultaneously. Here, we investigated the effect of male age and previous sexual experience on mating success and female fitness in the Mexican fruit fly,Anastrepha ludens(Diptera: Tephritidae). Males were either young or old, sexually experienced or naïve. Older and sexually experienced males obtained more copulations. However, females did not receive benefits in terms of lifetime fecundity, fertility, or longevity from mating with these males. Results suggest that males become more competitive as they age and gain sexual experience and may be able to maintain a high quality ejaculate compared to young males. Older experienced males may be manipulating females into preferentially mating with them at no benefit to females. Alternatively, females may prefer mating with older more experienced males and possibly receive other indirect benefits, but this remains to be tested.
Molecular Diversity of Puccinia melanocephala Populations
Authors: Pocovi Mariana Inés , Rech Gabriel Eduardo , Collavino Norma Graciela , Caruso Graciela Beatriz , Ríos Raúl , Mariotti Jorge Alberto 
Published: May 2010

AbstractAFLP analysis was carried out to assess genetic variability and determine the population structure of the sugarcane rust Puccinia melanocephala in northwest Argentina. Molecular data were also used to clarify whether genetic variation was correlated with host variation and/or the geographic distribution of the disease. Bulk rust uredospores were collected in the field, and both the geographical area and the infected host sugarcane cultivar were recorded. A total of 538 AFLP markers generated with 20 primer combinations were used to perform the genetic analysis. The percentage of polymorphic loci was quite high (85.7%), considering that P. melanocephala only reproduces asexually. Cluster analysis (UPGMA) and principal co‐ordinate analysis (PCoA) grouped populations from distinct geographic and host origins, suggesting that neither geographical region nor sugarcane variety constrains the relationships among the populations. This finding was corroborated by a lack of significant correlation between genetic distance and geographic distance (r = 0.057; P = 0.285). The non‐significant differences found between rust populations collected from distinct sugarcane varieties (PhiT = 0.026; P = 0.06) also support these results. Analysis of Molecular Variance Approach (AMOVA) analysis attributed most of the variation (95%) to differences within populations. No genetic structure was detected, and the populations behaved as a large undifferentiated population with high level of genetic variability.
Inhibiting Virus Infection by RNA Interference of the Eight Functional Genes of the Potato Virus Y Genome
Authors: Chen Xuemei , Liu Jing , Xu Li , Jiang Fang , Xie Xueying , Zhu Changxiang , Wen Fujiang 
Published: May 2010

AbstractThe genome of Potato virus Y is a single‐stranded, positive‐sense RNA molecule that encodes a single large polypeptide that is cleaved by self‐encoded proteases into 10 functional proteins. Using specific primers designed based on the cloned genome sequence of the necrotic strain of Potato virus Y (PVYN), we amplified 400 bp and 500 bp cDNA fragments from the 3′ ends of P1, HC‐Pro, P3, CI, Vpg, NIa, NIb and CP genes. These cDNA fragments were then inserted into the binary vector pROKII to construct the vectors pROK‐P1, pROK‐HC‐Pro, pROK‐P3, pROK‐CI, pROK‐NIa‐Vpg, pROK‐NIa‐Pro, pROK‐NIb and pROK‐CP, all of which contained hairpin RNAs (hpRNAs). These recombinant binary vectors were introduced into Agrobacterium tumefaciens strain LBA4404 and then into Nicotiana tabacum L. var. NC89 plants, respectively. Virus challenge inoculation indicated that the plants transformed with each construct were resistant to PVY infection, and the percentage of resistant plants obtained ranged from 33–64%. Northern blot showed an inverse correlation between transgenic transcript accumulation and virus resistance. siRNAs could be detected in all the resistant plants. We also studied the relationship between the secondary structure and the gene‐silencing efficiency and found a positive correlation between local free energies (ΔGloc) and the virus‐resistance ratio. For each construct, one line of progeny T1 was randomly selected to analyse the inheritance of the transgene and the resistance. All transgenic single locus lines were completely resistant, and this resistance could be stably inherited.
Evaluation of Genetic Diversity of Highly Virulent Strains of Xanthomonas campestris pv. malvacearum by rep‐PCR Fingerprinting
Authors: Zhai Jinling , Luo Yuehua , Zheng Daojun , Huang Xi 
Published: May 2010

AbstractHighly virulent strains (HVSs) of Xanthomonas campestris pv. malvacearum (Xcm) infect all commercial cultivars of cotton including the resistant cultivar ‘101‐102B’. Previous reports showed that different HVS isolates caused distinct symptoms on host. To evaluate the global genetic diversity of Xcm as well as HVS, 38 strains including 12 HVSs isolated from different countries were analysed by repetitive sequence (rep)‐based PCR with ERIC and BOX primer sets. rep‐PCR showed abundant polymorphism of fingerprinting. The strains were separated into different genotypic groups at a similarity coefficient of 0.76 using a UPGMA analysis. Interestingly, the strains with low or moderate virulence were clustered in one genogroup, whereas all HVSs isolated in Africa were segregated in another genogroup. These results suggest that the virulence of Xcm was highly related to genotype and/or geoclimatic origin of the strains. Additionally, the HVSs could be divided into two subgroups at a similarity coefficient of 0.80, indicating the genetic diversity of HVSs.
Chemical defenses against generalist fish predators and fouling organisms in two invasive ahermatypic corals in the genus Tubastraea
Authors: Lages Bruno G. , Fleury Beatriz G. , Pinto Angelo C. , Creed Joel C. 
Published: May 2010

AbstractThe introduction of exotic marine species has caused considerable economic and ecological damage around the world. Some of these species possess adaptations such as secondary metabolites which facilitate their successful invasion into new areas. In this study we tested two hypotheses: (i) crude extracts produced by two invasive hard corals Tubastraea coccinea and Tubastraea tagusensis, introduced to the southwest Atlantic, inhibit predation by generalist fish; (ii) substances found in the crude extracts of both species reduce or enhance the settlement of other organisms. In an in situ palatability bioassay the extract of T. tagusensis reduced predation by generalist fish. The extracts of both species of coral showed species‐specific effects on fouling organisms in in situ gel plate bioassays. Control and extract plates had similar total cover, although plates with extracts had significantly fewer Cladophora sp., and Lithophyllum sp. was only detected on control gels. In contrast, a hydrozoan was only found on plates with extracts and overall community ordination demonstrated clear differences in the fouling communities between treatments. These results demonstrate that both coral species have chemical substances which can bring about a negative interaction with potential fish predators and competitors such as algal and invertebrate foulers and the advantage gained could explain their success in invading new regions to the detriment of local fauna and flora.
Malignant non‐teratoid medulloepithelioma of the optic nerve with intraocular extension
Authors: Pushker Neelam , Shrey Dinesh , Bajaj Mandeep S , Kashyap Seema , Yadav Prashant , Mehta Mridula , Bakhshi Sameer 
Published: May 2010

AbstractMedulloepithelioma is an uncommon tumour. These tumours most commonly arise in the brain and spinal cord; however, they also may arise from the optic nerve. We, herein, report a rare case of malignant non‐teratoid medulloepithelioma of the optic nerve with intraocular extension.
Orbital steroid injection versus oral steroid therapy in management of thyroid‐related ophthalmopathy
Authors: Alkawas Ayman A , Hussein Atef M , Shahien Ezzat A 
Published: May 2010

AbstractBackground:  The aim of this study was to evaluate the efficacy, safety and complications of orbital steroid injection versus oral steroid therapy in the management of thyroid‐related ophthalmopathy.Methods:  A total of 29 patients suffering from thyroid ophthalmopathy were included in this study. Patients were randomized into two groups: group I included 15 patients treated with oral prednisolone and group II included 14 patients treated with peribulbar triamcinolone orbital injection. Only 12 patients in both groups (16 female and 8 male) completed the study.Results:  Both groups showed improvement in symptoms and in clinical evidence of inflammation with improvement of eye movement and proptosis in most cases. Mean exophthalmometry value before treatment was 22.6 ± 1.98 mm that decreased to 18.6 ± 0.996 mm in group I, compared with 23 ± 1.86 mm that decreased to 19.08 ± 1.16 mm in group II. Mean initial clinical activity score was 4.75 ± 1.2 and 5 ± 1.3 for group I and group II before treatment, respectively, which dropped to 0.83 ± 1.2 and 0.83 ± 1.02, 6 months after treatment, respectively. There was no change in the best‐corrected visual acuity in both groups. There was an increase in body weight, blood sugar, blood pressure and gastritis in group I in 66.7%, 33.3%, 50% and 75%, respectively, compared with 0%, 0%, 8.3% and 8.3% in group II. No adverse local side effects were observed in group II.Conclusion:  Orbital steroid injection for thyroid‐related ophthalmopathy is effective and safe. It eliminates the adverse reactions associated with oral corticosteroid use.
Comparison of grafted and non‐grafted patients with corneal astigmatism undergoing cataract extraction with a toric intraocular lens implant
Authors: Stewart Christopher M , McAlister James C 
Published: May 2010

AbstractBackground:  Toric intraocular lenses (IOLs) are advocated as an effective treatment for both regular corneal‐based astigmatism and cataract in both non‐penetrating keratoplasty and penetrating keratoplasty (PK) patients. The aim of this analysis is to compare postoperative outcomes for both PK and non‐PK patients to determine whether or not the past PK is relevant when calculating the appropriate IOL and predicting the postoperative results.Methods:  A retrospective analysis was performed on 14 non‐PK and eight PK patients who underwent cataract surgery and astigmatism correction with a Rayner toric IOL. Preoperatively, best spectacle‐corrected visual acuity, biometry and refractive data were recorded. Postoperative analysis at 1 month looked at best‐uncorrected visual acuity (BUVA), refractive data and IOL axis. Statistical analysis was undertaken to test for differences in outcomes between the PK and non‐PK groups.Results:  Preoperatively, a significant difference was seen between cylinder and astigmatism and not between sphere, axial length or anterior chamber depth. Analysis of preoperative best spectacle‐corrected visual acuity, IOL error predictability, IOL rotational stability and refractive outcomes revealed no difference between PK and non‐PK groups, but a significant difference was seen postoperatively with PK patients having worse BUVA.Conclusion:  Toric IOLs are an effective means for treating both regular corneal‐based astigmatism and cataract in both PK and non‐PK patient groups. Analysis of results revealed similar trends for both groups in all areas except postoperative BUVA. Further studies are planned to better understand why PK patient's BUVA did not fit the trend of the other results.
Training and using mid‐level eye care workers: early lessons from Timor‐Leste
Authors: Palagyi Anna , Brian Garry , Ramke Jacqueline 
Published: May 2010

AbstractBackground:  A 12‐month Diploma of Eye Care course for mid‐level eye care workers was initiated in 2007 as part of Timor‐Leste's National Eye Health Strategy. This paper reports the development and implementation of this course, examines its initial results and makes suggestions for improvements to the training and deployment of these workers.Methods:  Course curriculum development and delivery, trainee selection and candidate assessment were examined. Graduate clinical knowledge retention at 6 months after course completion was investigated using clinical vignettes to determine diagnosis, management and patient counselling knowledge for common primary eye health conditions. Graduate workplace environments and activities were appraised.Results:  Development of the course curriculum and its delivery were in response to local circumstance, and according to education best practice teaching and learning strategies. Four rural nurses successfully completed the inaugural course. Although all remained in rural eye care services at 6 months after graduation, there was considerable variation in activity. Substantial depletion of clinical competency was revealed across the cohort.Conclusions:  Adherence to current best practice in the design and delivery of the curriculum and course was insufficient to ensure productive graduates of ongoing clinical competency, positioned to make an impact on eye health. Attention needs to be directed to postgraduation integration into the workplace, and continuing support once there. The efficacy of this mid‐level cadre and its impact on eye health requires further evaluation.
Probabilistic prediction of high cycle fatigue reliability of high strength steel butt‐welded joints
Authors: SGHAIER R. BEN , BOURAOUI CH. , FATHALLAH R. , DEGALLAIX G. 
Published: May 2010

ABSTRACTThe aim of this paper is to develop a probabilistic approach of high cycle fatigue (HCF) behaviour prediction of welded joints taking into account the surface modifications induced by welding and the post‐welding shot peening treatment. In this work, the HCF Crossland criterion has been used and adopted to the case of welded and shot peened welded parts, by taking into account the surface modifications which are classified as follows: (i) the compressive residual stresses, (ii) the surface work‐hardening, (iii) the geometrical irregularities and (iv) the superficial defects. The random effects due to the dispersions of: (i) the HCF Crossland criterion material characteristics (ii) the applied loading and (iii) the surface modifications parameters are introduced in the proposed model. The HCF reliability has been computed by using the ‘strength load’ method with Monte Carlo simulation. The reliability computation results lead to obtain interesting and useful iso‐probabilistic Crossland diagrams (PCD) for different welding and shot peening surface conditions. To validate the proposed method, the approach has been applied to a butt‐welded joint made of S550MC high strength steel (HSS). Four types of specimens are investigated: (i) base metal (BM), (ii) machined and grooved (MG) condition, (iii) As welded (AW) condition and (iv) as welded and shot peened (AWSP) condition. The comparison between the computed reliabilities and the experimental investigations reveals good agreement leading to validate the proposed approach. The effects of the different welded and post‐weld shot peened specimen's surface properties are analysed and discussed using the design of experiments (DoE) techniques.
BimEL as a possible molecular link between proteasome dysfunction and cell death induced by mutant huntingtin
Authors: Leon Rebecca , Bhagavatula Nithya , Ulukpo Onome , McCollum Mark , Wei Jianning 
Published: May 2010

AbstractHuntington’s disease (HD) is a devastating neurodegenerative disorder caused by an expanded polyglutamine repeat within the N‐terminus of the huntingtin protein. It is characterized by a selective loss of medium spiny neurons in the striatum. It has been suggested that impaired proteasome function and endoplasmic reticulum (ER) stress play important roles in mutant huntingtin (mHtt)‐induced cell death. However, the molecular link involved is poorly understood. In the present study, we identified the essential role of the extra long form of Bim (Bcl‐2 interacting mediator of cell death), BimEL, in mHtt‐induced cell death. BimEL protein expression level was significantly increased in cell lines expressing the N‐terminus of mHtt and in a mouse model of HD. Although quantitative RT‐PCR analysis indicated that BimEL mRNA was increased in cells expressing mHtt, we provided evidence showing that, at the post‐translational level, phosphorylation of BimEL played a more important role in regulating BimEL expression. Up‐regulation of BimEL facilitated the translocation of Bax to the mitochondrial membrane, which further led to cytochrome c release and cell death. On the other hand, knocking down BimEL expression prevented mHtt‐induced cell death. Taken together, these findings suggest that BimEL is a key element in regulating mHtt‐induced cell death. A model depicting the role of BimEL in linking mHtt‐induced ER stress and proteasome dysfunction to cell death is proposed.
Interaction of a novel mitochondrial protein, 4‐nitrophenylphosphatase domain and non‐neuronal SNAP25‐like protein homolog 1 (NIPSNAP1), with the amyloid precursor protein family
Authors: Tummala Hemachand , Li Xiaofan , Homayouni Ramin 
Published: May 2010

AbstractAmyloid precursor protein (APP) and its paralogs, amyloid precursor‐like protein‐1 and amyloid precursor‐like protein‐2, appear to have redundant but essential role(s) during development. To gain insights into the physiological and possibly pathophysiological functions of APP, we used a functional proteomic approach to identify proteins that interact with the highly conserved C‐terminal region of APP family proteins. Previously, we characterized an interaction between APP and ubiquitous mitochondrial creatine kinase. Here, we describe an interaction between APP and a novel protein, 4‐nitrophenylphosphatase domain and non‐neuronal SNAP25‐like protein homolog 1 (NIPSNAP1). The interaction between APP and NIPSNAP1 was confirmed both in transiently transfected COS7 cells and in the mouse brain, where NIPSNAP1 is expressed at a high level. We demonstrate that NIPSNAP1 is targeted to the mitochondria via its N‐terminal targeting sequence, and interacts with mitochondrial chaperone translocase of the outer membrane 22. Mitochondrial localization of NIPSNAP1 appears to be critical for its interaction with APP, and overexpression of APP appeared to disrupt NIPSNAP1 mitochondrial localization. Moreover, APP overexpression resulted in downregulation of NIPSNAP1 levels in cultured cells. Our data suggest that APP may affect mitochondrial function through a direct interaction with NIPSNAP1 as well as with other mitochondrial proteins.