bluuebunny/crossref_metadata_2025 huggingface dataset:
Positioning of Sex-Correlated Markers for Populus in a AFLP- and SSR-Marker Based Genetic Map of Populus tremula x tremuloides
Authors: Markussen T. , Pakull B. , Fladung M.
Published: October 2017

A preliminary consensus map of Populus tremula x tremuloides has been constructed from an interspecific hybrid population of 66 seedlings of the cross Brauna 11 (P. tremula) x Turresson 141 (P. tremuloides). The map was constructed based on 205 AFLP- and 29 SSR-markers covering 1875cM on 19 linkage groups. A single locus correlating to sex in Populus was mapped close to two AFLP-markers. The map will be used as a starting point for the identification of sex-related genes or molecular markers and their fine mapping based on a BAC-library screening.
Studies on Cytogenetical Variation in Prosopis cineraria (Linn.) Druce – A Key Stone Tree Species of Indian Desert
Authors: Rawat D. , Kumar A. , Rao S. R.
Published: October 2017

Prosopis cineraria (Mimosaceae) is an important tree of agro-forestry and ethano- botanical importance with multipurpose utility as wood yielding, fodder, food and medicinal uses. Some remarkable features are observed in the form of phenotypic variation in various populations inhabiting different regions of the Indian desert. To asses these variations male meiotic studies were conducted in ten different accessions collected from four proviences of Rajasthan, India. Analysis of data on chromosome associations, chiasma frequency and their distributions pattern concluded that the somatic chromosome number of P. cineraria is 2n = 2x = 28. The complete absence of accessory chromosomes (B) and percentage of pollen stainability indicates an over all genomic stability in P. cineraria. Numerical changes like aneuploidy might have played an important role in origin and adoptation of P. cineraria against all the odds of the climatic condition of the Indian desert.
Factors Influencing Male Reproductive Success in a Cryptomeria japonica Seed Orchard Revealed by Microsatellite Marker Analysis
Authors: Moriguchi Y. , Tsuchiya S. , Iwata H. , Itoo S. , Tani N. , Taira H. , Tsumura Y.
Published: October 2017

We investigated the influence of male flower production, floral synchrony and inter-tree distances on male reproductive success in a miniature seed orchard of Cryptomeria japonica. We used six microsatellite markers to determine the paternity of each seed. In the seed orchard, the average pollen contamination and clonal self-fertilization rates were 38.7% and 1.7%, respectively. The level of male reproductive success of constituent clones varied from 0.0 to 15.7%. Five clones showing the highest male reproductive success contributed ca. 30% of all analyzed seeds as a pollen donor after excluding contamination by external sources of pollen. The statistical analyses showed that male reproductive success was strongly influenced by male flower production of each clone and, possibly, by their distance to the mother trees. The linear regression which included male flower production and floral synchrony as independent variables, however, accounted for only 14.7% of variation of male reproductive success, suggesting that other factors such as pollen competition might also influence male reproductive success. Since we found no significant correlation between male reproductive and female reproductive successes, it may be better to equalize male and female reproductive successes independently
Age-related Trends in Genetic Parameters for Jack Pine and Their Implications for Early Selection
Authors: Weng Y. H. , Tosh K. J. , Park Y. S. , Fullarton M. S.
Published: October 2017

Trends in genetic parameters for height growth of jack pine (Pinus banksiana Lamb.) were examined over three series of family tests throughout New Brunswick. Data were analyzed for each site and across sites within each series. Although individual narrow sense heritability estimates from single-site analyses varied substantially from site to site and showed no consistent age-related pattern, the estimates from across-site analyses showed an increasing trend to age 20. Similar as individual narrow sense heritability, the coefficient of additive genetic variance estimated from single site showed more variation than those estimated from across site analyses. Age-age (type-a) genetic correlations for height were high and could be well predicted by a LAR2model, where LAR is the natural logarithm of the ratio between two ages at assessment. Type-b genetic correlations were high and of similar magnitude at different ages. Genetic correlations between height at different ages and volume at one-half rotation age were generally high. Taking the volume at one-half rotation age as the target trait, the selection for target trait from early selection at ages 5~7 could be more efficient per year than direct selection.
Deterministic Simulation of Gains for Seedling and Cloned Main and Elite Breeding Populations of Pinus radiata and Implications for Strategy
Authors: Shelbourne C. J. A. , Kumar S. , Burdon R. D. , Gea L. D. , Dungey H. S.
Published: October 2017

Genetic gains in breast-height diameter were estimated using deterministic simulation. Simulations of gain from one generation of selection were undertaken in large Main and small Elite breeding populations for a range of heritabilities, with varying numbers of parents, families, seedlings/family, clones/family and ramets/ clone to aid revision of the New Zealand Pinus radiata breeding strategy. Cloned versus seedling populations of equal numbers of plants were simulated, derived from open pollination, polycrossing, and pair crossing. Balanced within-family selection was used for 200, 400 and 800-parent Main breeding populations and among- and within-family selection for 25-parent Elite populations of 25 up to 100 full-sib families. Predicted gains from within-family selection in the Main population were highest from cloned polycross families at all heritabilities and lowest for seedling fullsib families. Gains from cloned populations were higher than seedling equivalents at heritabilities ≤0.5, and their advantage in gain was greatest at lower heritabilities. Elite populations of 25 parents showed similar trends but intensive among- and within-family selection resulted in much higher gains than from the Main, highest from the cloned options. The increase in gain with increased number of families diminished with more than 2-3 times as many families as parents. A new strategy was proposed for P. radiata, based on the simulation results, involving an expanded Main breeding population of open-pollinated (OP) seedling families, together with pair-cross family seedlots already available, supported by parentage reconstruction using DNA markers. Forwards selection in small cloned Elite populations was proposed as the main source of seed orchard clones.
Genetic Parameter Estimates for Growth Traits from Diallel Tests of Loblolly Pine Throughout the Southeastern United States
Authors: Mckeand S. E. , Li B. , Grissom J. E. , Isik F. , Jayawickrama K. J. S.
Published: October 2017

Variation in heritability and in genetic correlation estimates were evaluated for juvenile tree height and volume for six testing areas of loblolly pine (Pinus taeda L.) in the southeastern United States. Variance components and their functions (heritability and type B genetic correlations) were estimated from 265 six-parent disconnected diallel series, tested in almost 1000 trials (4 tests per diallel series). Original data were collected at age 6 years from about one million trees (265 diallel series x 30 crosses x 36 trees per cross/site x 4 sites) planted in field tests. Genetic tests were from the second cycle of breeding in the North Carolina State University - Industry Cooperative Tree Improvement Program. The overall unbiased individual-tree narrow-sense heritability for height was 0.19 and for volume was 0.16. The broad-sense heritabilities for height (0.24) and for volume (0.22) were higher than narrow-sense heritabilities due to the presence of non-additive genetic variance. There were moderate regional differences in these estimates, with tests in the Lower Gulf Coastal Plain tending to have the highest heritabilities for growth traits. There was very little association between site index and heritability, but heritabilities were higher on sites with the highest survival and highest test precision. Genotype x environment interactions were generally low both for half-sib and full-sib families, indicating that families can be operationally deployed to different sites with little concern about unpredictable performance.
Genetic Variation in Reproductive Traits in a Clonal Seed Orchard of Prunus avium in Northern Spain
Authors: Díaz R. , Merlo E.
Published: October 2017

In the present study we investigated the reproductive phenology of Prunus avium in a seed orchard located in northwestern Spain. The study was carried out with 103 clones from 7 provenance regions in northern Spain. The most advanced flowering stage on different dates and the number of flowers and cherries were monitored over two consecutive years. Significant differences among clones were found for all of the studied traits, with high broad-sense heritability estimates for all, except duration of flowering and synchronization index, both of which showed moderate heritability. In general, there was good overall reproductive synchronization in the seed orchard, although two groups of clones were differentiated. Clones from two out of the seven populations studied flowered later and were less well synchronized. The clonal differentiation was correlated with geoclimatic variables, suggesting that clones from lower altitudes and higher temperatures tend to an earlier flowering.
Strategies for Optimal Deployment of Related Clones into Seed Orchards
Authors: Danusevičius D. , Lindgren D.
Published: October 2017

This study deals with how the deployed proportion of each candidate clone can be decided at the establishment of a seed orchard when the breeding values are available for each candidate in a population of unrelated half-sib families. The following deployment strategies were compared: (a) truncation selection by selecting the clones with the breeding values exceeding certain threshold and deploying equal number of ramets (Truncation strategy); (b) truncation selection by selecting only one best individual within each family (Truncation unrelated); (c) maximizing gain at a given effective clone number (Linear deployment); (d) linear deployment by selecting one best individual within each family (Linear deployment unrelated) and (e) maximizing net gain at a given gene diversity (Optimal proportions). The study focused on the latest alternative and described its superiority and characteristics for a number of possible typical cases. The genetic gain adjusted for predicted inbreeding depression (Net gain), gene diversity and effective clone number were considered as the main ranking criteria. The strategies optimizing the number of related individuals and the linear deployment strategy with restriction on relatedness returned the highest Net gain. If there is a large diversity to select from (the status number of the candidates is more than 8 times greater than the status number desired in the seed orchard), a relatively simple advice is to select the best individual within the best families and deploy the clones linearly according to their breeding values (the number of families selected depends on the desired status number). If the diversity available to select from is small, it seems recommendable to allow half-sibs among the selections and use the Optimal proportions deployment strategy. As the breeding cycles proceed, the status number of the candidate population will decrease and the Optimal proportions strategy is likely to become more favorable.
Mixed Mating With Preferential Outcrossing in Acacia saligna (Labill.) H. Wendl. (Leguminosae: Mimosoideae)
Authors: George N. , Byrne M. , Yan G.
Published: October 2017

Acacia saligna is being developed as an agroforestry crop for the southern agricultural regions of Australia. This study investigated the breeding system of A. saligna to generate basic knowledge for breeding and utilization of the species. Allozyme markers were used to investigate the mating system of four populations of the species. All the populations had high outcrossing rates, with a mean multilocus outcrossing rate of 0.91. The implications of a highly outcrossed mating system to the utilization of A. saligna are discussed.
Genetics of Shrinkage in Juvenile Trees of Pinus radiata D. Don From Two Test Sites in Australia
Authors: Gapare W. J. , Ivković M. , Powell M. B. , McRae T. A. , Wu H. X.
Published: October 2017

To examine the genetic control of wood shrinkage (radial, tangential and longitudinal) in juvenile wood of radiata pine (Pinus radiata D. Don), we assessed samples collected at breast height in two related progeny tests of age 8 and 9 years, established at two different sites in Australia. Green to oven-dry tangential and radial shrinkage for the outer-rings was similar at both sites. Similarly, mean longitudinal shrinkage for the outer-rings was similar at both sites (0.3%, ranging from 0.1 to 1.9 at Flynn and 0.4%, ranging from 0.02 to 1.6, at Kromelite). Mean longitudinal shrinkage for the inner-rings was 4 times greater than that of the outerrings at both sites. The magnitude of the gradient of longitudinal shrinkage from pith to bark (0.001 to 2.9%) is large enough to cause distortion problems including twist and warp, during drying of sawn boards. These values also suggest that shrinkage in the juvenile core of radiata pine is of major economic importance and therefore should be improved either through genetics or silviculture. Individual-tree narrow-sense individual heritability for tangential and radial shrinkage in the outer-rings (4-6) was moderate at Flynn (0.24 ± 0.09 and 0.26±0.07, respectively). There was a lack of significant genetic variation for longitudinal shrinkage in the outer-rings but significant genetic control for the inner-rings (1-2) (h2 = 0.26 ± 0.07). More samples per family are required to detect significant genetic variation for shrinkage traits than other traits due to higher background variation in sampling and measuring shrinkage traits relative to other wood quality traits such as density, microfibril angle (MfA), spiral grain and modulus of elasticity (MoE).
Genetic Variation in Frost Damage and Seed Zone Delineation within an Altitudinal Transect of Pinus devoniana (P. michoacana) in Mexico
Authors: Sáenz-Romero C. , Tapia-Olivares B. L.
Published: October 2017

We explored the patterning of genetic variation among Pinus devoniana Lindl. (also known as P. michoacana Martínez) populations to develop guidelines for seed and seedling movements, intended for improving the matching between genotypes and environments regarding frost tolerance, in reforestation programs. Open-pollinated seed from 16 populations along an altitudinal transect (1600 to 2450 m) were collected near Morelia, State of Michoacán, México. A common-garden provenance test, established with 2.5-year-old seedlings, was assessed for frost resistance conducting a laboratory frost damage test (-9°C). Results indicate that there were significant differences among provenances (P = 0.0261) for frost damage. Variation among provenances was structured as an altitudinal cline, with populations from lower altitudes being the least tolerant to frost. Linear regression statistics suggest that for each increment of 100 m of provenance altitude, there will be a 5.2% decrease in frost damage. We suggest the use of two provisional altitudinal seed zones of 400 m breadth each (lower and upper limits for zone 1: 1600 m and 2000 m of altitude; for zone 2: 2000 and 2400 m, respectively), and for reforestation of a given site, the use of seedlings originated from seed of the same seed zone or within ±200 m of altitude from the elevation of the reforestation site.
Evaluation of Provenances of Eucalyptus camaldulensis and Clones of E. camaldulensis and E. tereticornis at Contrasting Sites in Southern India
Authors: Varghese M. , Harwood C. E. , Hegde R. , Ravi N.
Published: October 2017

A total of 188 open-pollinated families of Eucalyptus camaldulensis Dehnh. from 18 Australian natural provenances and 15 selected Indian families of the “Mysore Gum” land race were evaluated in three provenance- family trials at contrasting sites in southern India. At two years of age, the fastest growth was recorded at the driest site in Tamil Nadu, where E. camaldulensis provenances from Queensland were superior to those from Northern Territory and Western Australia, and the Indian land race. Provenance differences were less pronounced at the two higher-rainfall sites in Andhra Pradesh and Kerala. Interaction of provenance performance with site was significant. Within- provenance individual-tree heritabilities for height and diameter at breast height (dbh) were low at the three individual sites, ranging from 0.08 ± 0.05 to 0.19 ± 0.05 for height and 0.10 ± 0.05 to 0.19 ± 0.04 for dbh. Across-site heritabilities, 0.07 ± 0.02 for both height and dbh, were lower than those at individual sites. Phenotypically superior trees were selected from these trials and seven other plantings of E. camaldulensis and Eucalyptus tereticornis Smith in southern India and cloned from basal coppice. A total of 78 E. camaldulensis and 27 E. tereticornis selections, together with thirteen commercially planted Eucalyptus clones and five superior natural provenance seedlots, were tested in clonal trials at three sites in southern India, the different individual treatments being tested at from one to three sites. Three years after planting, most clones selected from E. camaldulensis trials and the commercial Eucalyptus clones were superior in volume production to E. tereticornis clones and seedling controls at a dry site in Tamil Nadu. A smaller number of clones, particularly those of E. camaldulensis, were also superior to seedling controls at an intermediate-rainfall site in Andhra Pradesh. At a third high-rainfall site in Kerala, seedling controls were superior to all but four of 46 clones tested. Significant clone-by-site interaction was observed for growth traits. At the dry site in Tamil Nadu, clones varied widely in their wood basic density from 450 to 700 kg m-3, and there was no significant correlation of clonal values for growth and wood density. The results confirm that clones are best selected and tested in environments similar to those where they will be deployed.
Short Note: The Genetic Correlation Between Air-dried Density and Basic Density in Eucalyptus Nitens Wood Cores
Authors: Hamilton M. G. , Raymond C. A. , Potts B. M.
Published: October 2017

Cores extracted from trees to assess wood chemistry are generally not used to assess basic density in eucalypt pulpwood breeding programmes, as the measurement of basic density requires high temperature drying. However, both wood chemistry and air-dried density can be assessed on the same core. This study found that the inter-trait genetic correlation between core air-dried and basic density to be effectively equal to one in two Tasmanian Eucalyptus nitens progeny trials. This implies that selection for basic density could be undertaken using air-dried density with little or no reduction in genetic gain, thus negating the need to extract a separate core to assess basic density and wood chemistry. The adoption of this practice could considerably reduce the cost of assessing these traits in eucalypt breeding programmes.
Heterogeneity and Spatial Autocorrelation for Chloroplast Haplotypes in Three Old Growth Populations of Northern Red Oak
Authors: Feng Y. , Sun W. , Romero-Severson J.
Published: October 2017

In eastern North America, evidence for cryptic northern refugia could contribute to resolving Reid’s Paradox, the disparity between the rate of oak recolonization indicated by pollen deposition and the rate indicated by contemporary seed dispersal studies. Severe anthropogenic disturbance of oak-dominated forests throughout eastern North America followed by regeneration from isolated patches and deliberate planting in some regions could obscure the signal of discontinuity expected from small, cryptic refugia. In this study of northern red oak, Quercus rubra L., the dominant representative of Quercus section Lobatae in the eastern United States, we address the question of appropriate sample size for accurate detection of the biogeographical distribution of chloroplast haplotype diversity in Q. rubra. We examined chloroplast DNA (cpDNA) variation in all Q. rubra over 17 cm in diameter (310 trees) in three forest fragments with documented histories of minimal disturbance for the last 100-190 years. cpDNA polymorphisms in three intergenic regions revealed different haplotype frequencies between the two local fragments located within 1 km of each other and complete discontinuity for the predominant haplotype between these two sites and a site 207 km distant. Haplotypes displayed positive spatial autocorrelation over 10-40 meter distances. Sample sizes of 10 or fewer taken at 50 meter intervals along a linear transect yielded poor estimates of haplotype frequencies and did not accurately detect haplotype richness.
The Needle Volatile Composition of Pinus nigra J. F. Arnold, P. sylvestris L., P. densiflora Siebold et Zucc. and P. thunbergiana Franco Trispecies Hybrids
Authors: Pfeifhofer H. W. , Idžojtižć M. , Zebec M.
Published: October 2017

The needle volatile composition of two trispecies hard pine hybrids produced by the controlled hybridization and their parents was researched with gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) in order to confirm their hybridity. The analysed trispecies hybrids were: (Pinus nigra x P. sylvestris) x P. densiflora (= nisyde) and (P. nigra x P. sylvestris) x P. thunbergiana (= nisyth). A total of 59 compounds was identified. All identified compounds were terpenes, except one. The trispecies hybrids showed the same qualitative pattern of the needle volatile composition as their parental species. However, there were quantitative differences in several major terpenes. According to the needle volatile composition the hybrids nisyde were more similar to the female parent, whereas the hybrids nisyth were more similar to the male parent. The hybrids nisyth had a considerably higher content of β-pinene (specific component of P. thunbergiana) than the other analyzed groups. The content of thunbergol (specific component of P. densiflora) in the hybrids nisyde was not considerably different in relation to the other groups. The intermediary quality of the hybrids nisyde and nisyth for most components in relation to their parents, as well as the previous morphometric analysis, confirms their hybrid character.
Genetic Variation Within Two Sympatric Spotted Gum Eucalypts Exceeds Between Taxa Variation
Authors: Ochieng J. W. , Shepherd M. , Baverstock P. R. , Nikles G. , Lee D. J. , Henry R. J.
Published: October 2017

Population substructure and hybridization, among other factors, have the potential to cause erroneous associations in linkage disequilibrium (LD) mapping. Two closely related spotted gum eucalypts, Corymbia variegata and C. henryi (Myrtaceae) occur in sympatry in the east coast of Australia and potentially interbreed. They are morphologically similar but are distinguished as separate species based on capsule and foliage size. To determine whether they hybridize in nature and its implications for LD mapping, we investigated the level of molecular divergence between the two species at two sympatric locations separated by 300 kilometres. Very few individuals of intermediate morphology were identified, despite the two species occurring only metres apart. Analysis of genetic structure using 12 microsatellite loci showed that genetic differentiation between populations of the same species at different locations (FST= 0.07 for both species; p = 0.0001) was significantly higher than that observed between species at each location (mean FST= 0.02 and 0.04 for Cherry tree and Bunyaville respectively; p = 0.0001; all Mann-Whitney U-test p ≤ 0.01). No species-specific alleles or significant allele frequency differences were detected within a site, suggesting recurr#ent local gene flow between the two species. The lack of significant allele frequency differences implies no population stratification along taxonomic lines. This suggested that there is little concern for cryptic hybridization when sampling from sites of sympatry for LD mapping.
Discrimination between seedlings of Eucalyptus globulus, E. nitens and their F1 hybrid using near-infrared reflectance spectroscopy and foliar oil content
Authors: Humphreys J. R. , O’Reilly-Wapstra J. M. , Harbard J. L. , Davies N. W. , Griffin A. R. , Jordan G. J. , Potts B. M.
Published: October 2017

Identification of plant hybrids produced from closely related species can be difficult using morphological characteristics alone, particularly when identifying young seedlings. In this study, we compared the performance of three calibration models developed to discriminate between seedlings of Eucalyptus globulus, E. nitens and their first-generation hybrid using either foliar oil chemistry or near-infrared reflectance spectral data from fresh, whole leaves. Both oil and near-infrared reflectance spectroscopy (NIRS) models were developed using partial least-squares discriminant analysis and showed high classification accuracy, all correctly classifying more than 91% of samples in cross-validation. Additionally, we developed a larger, “global” and independently validated NIRS model specifically to discriminate between E. globulus and F1 hybrid seedlings of different ages. This model correctly classified 98.1% of samples in cross-validation and 95.1% of samples from an independent test set. These results show that NIRS analysis of fresh, whole leaves can be used as a rapid and accurate alternative to chemical analysis for the purpose of hybrid identification.
Genetic Parameters of Somatic Clones of Coastal Douglas-fir at 5½-Years across Washington and Oregon, USA
Authors: Dean C. A.
Published: October 2017

Five genetic tests involving 70 somatic clones of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) were planted March-April 1999 in Weyerhaeuser plantations across western Washington and Oregon states, USA. Four of the tests are in Longview and Twin Harbors regions of Washington, and one test is in Springfield, Oregon. Each test is based on single-tree plots with 12 randomized complete-blocks. The 70 coastal Douglas-fir clones were propagated by somatic embryogenesis from two full-sib families that had the same female parent. Results are reported for survival, height, diameter at breast-height (DBH) and volume growth at 5½-years. These tests provide evidence of acceptable growth and survival of somatic trees of coastal Douglas-fir across a range of site conditions. Height had a clonal heritability of 0.25 ± 0.01, DBH 0.21 ± 0.01 and volume 0.20 ± 0.01. The growth traits were all strongly genetically associated with clonal correlations of 0.92 to 0.99. Clonal performance for growth proved quite stable across tests with an overall between-test correlation of 0.84 ± 0.04. There was little variance due to clone x test interactions.
The Effect of Altitude on the Pattern of Gene Flow in the Endemic Canary Island Pine, Pinus canariensis
Authors: Navascués M. , Vendramin G. G. , Emerson B. C.
Published: October 2017

Pinus canariensis is endemic to the western Canary Islands (NW coast of Africa), where it forms forest spanning an altitude from 500 to 2500 m. There are dramatic changes in environmental conditions (temperature, moisture and solar radiation) over short distances due to this elevation gradient in the Canary Island pine forest. Those differences in environmental conditions may lead to asynchronous flowering times among elevations. In this study we used nuclear and chloroplast microsatellites to characterize the genetic structure of two altitudinal transects on the southern slopes of Tenerife Island to test for genetic isolation among altitudes. Although significant differentiation among sites was detected, this differentiation was very low (FST= 0.013 with chloroplast markers, FST= 0.019 with nuclear markers) and appeared to be unrelated to altitude. The contrasting results between nuclear and chloroplast markers are also discussed in terms of statistical accuracy of markers and genome inheritance.
Chancen und Risiken differenter Systemlogiken im Krankenhaus: Perspektiven einer Kooperation von Seelsorge und Spiritual Care
Authors: Karle Isolde
Published: October 2017

Gegenwärtig steht die Klinikseelsorge vor schwierigen Balanceakten. Will sie sich in Spiritual Care integrieren, wird sie Teil des multiprofessionellen Behandlungsteams im Krankenhaus und ihre konstruktiv irritierende Außenperspektive droht verloren zu gehen. Zugleich bietet sich etablierende Spiritual Care der Seelsorge viele Chancen. Seelsorge muss deshalb ein Interesse an einer Mitgestaltung von Spiritual Care im Krankenhaus haben. Der Beitrag benennt in diesem Sinn die Herausforderungen, Probleme und Chancen einer Kooperation von Spiritual Care und Seelsorge und fragt danach, welche Gesichtspunkte zwischen Dazugehörigkeit und bleibender Fremdheit zu beachten sind, damit Seelsorge weiterhin ihr spezifisch religiöses Potential zum Wohl von kranken und sterbenden Menschen zum Ausdruck bringen kann.
Grifolin attenuates white matter lesion in oxygen/glucose deprivation
Authors: Yanqin Ying , Jing Tang , Wei Chen , Nan Li
Published: October 2017

The present study evaluates the effect of grifolin (GFL) in oxygen/glucose deprivation (OGD) induced white matter lesion. Injury induced with OGD was found to be significant at the 9th h of OGD induction and the effect of GFL on the proliferation of oligodendrocyte precursor cells (OPCs) was assessed by CCK-8 and Hoechst 33258 assay at GFL 1, 5, 25, 50 and 100 μm concentrations. Whereas immunocytochemistry was performed for the assessment of survival and apoptosis of OPCs, western blot assay and RT-PCR were performed after 8th day of OGD injury for the estimation of expressions of myelin basic protein (MBP) and inhibitor of DNA binding 2 (Id2) in OPCs respectively. Results of the study suggests that treatment with GFL significantly enhances the survival rate and decreases the apoptosis of OPCs in OGD induced injury model. Immunocytochemical staining of Oligodendrocyte transcription factor (Olig2) and Bromodeoxyuridine (Brdu) shows that GFL treatment improves the proliferation of OPCs than OGD group. Moreover data of western blot assay suggested that treatment with GFL significantly enhances the expressions of MBP and Olig2 than OGD. It was observed that expressions of Id2 decreases and Olig2 enhances in GFL treated group than OGD group. Data of our study concludes that GFL enhances the differentiation and proliferation of OPCs in OGD-induced injury by altering the expressions of Id2 and Olig2.
Theoretical investigations of the local distortion and spectral properties for VO2+ in SiO2 Glass
Authors: Li Mu-Neng , Zhang Zhi-Hong , Wu Shao-Yi
Published: October 2017

The local distortions and the spin Hamiltonian parameters g factors g
∥, g
⊥ and the hyperfine structure constants A
∥ and A
⊥ for isolated vanadyl ions VO2+ doped in SiO2 glass at 700°C are theoretically investigated from the perturbation formulas of these parameters for a 3d1 ion in tetragonally compressed octahedra. In these formulas, the relationships between local structure of VO2+ ions center and the tetragonal crystal field parameters are established. As a result, the distortion of the ligand octahedron is attributed to the strong axial crystal-fields associated with the short V4+–O2− bond due to the strong V=O bonding in the silica matrix. The theoretical spin Hamiltonian parameters obtained in this work show reasonable agreement with the experimental data.
CB1-Dependent Long-Term Depression in Ventral Tegmental Area GABA Neurons: A Novel Target for Marijuana
Authors: Friend Lindsey , Weed Jared , Sandoval Philip , Nufer Teresa , Ostlund Isaac , Edwards Jeffrey G.
Published: October 2017

The VTA is necessary for reward behavior with dopamine cells critically involved in reward signaling. Dopamine cells in turn are innervated and regulated by neighboring inhibitory GABA cells. Using whole-cell electrophysiology in juvenile-adolescent GAD67-GFP male mice, we examined excitatory plasticity in fluorescent VTA GABA cells. A novel CB1-dependent LTD was induced in GABA cells that was dependent on metabotropic glutamate receptor 5, and cannabinoid receptor 1 (CB1). LTD was absent inCB1knock-out mice but preserved in heterozygous littermates. Bath applied Δ9-tetrahydrocannabinol depressed GABA cell activity, therefore downstream dopamine cells will be disinhibited; and thus, this could potentially result in increased reward. Chronic injections of Δ9-tetrahydrocannabinol occluded LTD compared with vehicle injections; however, a single exposure was insufficient to do so. As synaptic modifications by drugs of abuse are often tied to addiction, these data suggest a possible mechanism for the addictive effects of Δ9-tetrahydrocannabinol in juvenile-adolescents, by potentially altering reward behavioral outcomes.

SIGNIFICANCE STATEMENTThe present study identifies a novel form of glutamatergic synaptic plasticity in VTA GABA neurons, a currently understudied cell type that is critical for the brain's reward circuit, and how Δ9-tetrahydrocannabinol occludes this plasticity. This study specifically addresses a potential unifying mechanism whereby marijuana could exert rewarding and addictive/withdrawal effects. Marijuana use and legalization are a pressing issue for many states in the United States. Although marijuana is the most commonly abused illicit drug, the implications of legalized, widespread, or continued usage are speculative. This study in juvenile-adolescent aged mice identifies a novel form of synaptic plasticity in VTA GABA cells, and the synaptic remodeling that can occur after Δ9-tetrahydrocannabinol use.
Activity-Dependent Facilitation of CaV1.3 Calcium Channels Promotes KCa3.1 Activation in Hippocampal Neurons
Authors: Sahu Giriraj , Asmara Hadhimulya , Zhang Fang-Xiong , Zamponi Gerald W. , Turner Ray W.
Published: October 2017

CaV1 L-type calcium channels are key to regulating neuronal excitability, with the range of functional roles enhanced by interactions with calmodulin, accessory proteins, or CaMKII that modulate channel activity. In hippocampal pyramidal cells, a prominent elevation of CaV1 activity is apparent in late channel openings that can last for seconds following a depolarizing stimulus train. The current study tested the hypothesis that a reported interaction among CaV1.3 channels, the scaffolding protein densin, and CaMKII could generate a facilitation of channel activity that outlasts a depolarizing stimulus. We found that CaV1.3 but not CaV1.2 channels exhibit a long-duration calcium-dependent facilitation (L-CDF) that lasts up to 8 s following a brief 50 Hz stimulus train, but only when coexpressed with densin and CaMKII. To test the physiological role for CaV1.3 L-CDF, we coexpressed the intermediate-conductance KCa3.1 potassium channel, revealing a strong functional coupling to CaV1.3 channel activity that was accentuated by densin and CaMKII. Moreover, the CaV1.3–densin–CaMKII interaction gave rise to an outward tail current of up to 8 s duration following a depolarizing stimulus in both tsA-201 cells and male rat CA1 pyramidal cells. A slow afterhyperpolarization in pyramidal cells was reduced by a selective block of CaV1 channels by isradipine, a CaMKII blocker, and siRNA knockdown of densin, and spike frequency increased upon selective block of CaV1 channel conductance. The results are important in revealing a CaV1.3–densin–CaMKII interaction that extends the contribution of CaV1.3 calcium influx to a time frame well beyond a brief input train.

SIGNIFICANCE STATEMENTCaV1 L-type calcium channels play a key role in regulating the output of central neurons by providing calcium influx during repetitive inputs. This study identifies a long-duration calcium-dependent facilitation (L-CDF) of CaV1.3 channels that depends on the scaffolding protein densin and CaMKII and that outlasts a depolarizing stimulus by seconds. We further show a tight functional coupling between CaV1.3 calcium influx and the intermediate-conductance KCa3.1 potassium channel that promotes an outward tail current of up to 8 s following a depolarizing stimulus. Tests in CA1 hippocampal pyramidal cells reveal that a slow AHP is reduced by blocking different components of the CaV1.3-densin-CaMKII interaction, identifying an important role for CaV1.3 L-CDF in regulating neuronal excitability.
Sensorimotor Processing in the Basal Ganglia Leads to Transient Beta Oscillations during Behavior
Authors: Mirzaei Amin , Kumar Arvind , Leventhal Daniel , Mallet Nicolas , Aertsen Ad , Berke Joshua , Schmidt Robert
Published: October 2017

Brief epochs of beta oscillations have been implicated in sensorimotor control in the basal ganglia of task-performing healthy animals. However, which neural processes underlie their generation and how they are affected by sensorimotor processing remains unclear. To determine the mechanisms underlying transient beta oscillations in the LFP, we combined computational modeling of the subthalamo-pallidal network for the generation of beta oscillations with realistic stimulation patterns derived from single-unit data recorded from different basal ganglia subregions in rats performing a cued choice task. In the recordings, we found distinct firing patterns in the striatum, globus pallidus, and subthalamic nucleus related to sensory and motor events during the behavioral task. Using these firing patterns to generate realistic inputs to our network model led to transient beta oscillations with the same time course as the rat LFP data. In addition, our model can account for further nonintuitive aspects of beta modulation, including beta phase resets after sensory cues and correlations with reaction time. Overall, our model can explain how the combination of temporally regulated sensory responses of the subthalamic nucleus, ramping activity of the subthalamic nucleus, and movement-related activity of the globus pallidus leads to transient beta oscillations during behavior.

SIGNIFICANCE STATEMENTTransient beta oscillations emerge in the normal functioning cortico-basal ganglia loop during behavior. Here, we used a unique approach connecting a computational model closely with experimental data. In this way, we achieved a simulation environment for our model that mimics natural input patterns in awake, behaving animals. We demonstrate that a computational model for beta oscillations in Parkinson's disease (PD) can also account for complex patterns of transient beta oscillations in healthy animals. Therefore, we propose that transient beta oscillations in healthy animals share the same mechanism with pathological beta oscillations in PD. This important result connects functional and pathological roles of beta oscillations in the basal ganglia.
The Gain-of-Function Integrin β3 Pro33 Variant Alters the Serotonin System in the Mouse Brain
Authors: Dohn Michael R. , Kooker Christopher G. , Bastarache Lisa , Jessen Tammy , Rinaldi Capria , Varney Seth , Mazalouskas Matthew D. , Pan Hope , Oliver Kendra H. , Velez Edwards Digna R. , Sutcliffe James S. , Denny Joshua C. , Carneiro Ana M.D.
Published: October 2017

Engagement of integrins by the extracellular matrix initiates signaling cascades that drive a variety of cellular functions, including neuronal migration and axonal pathfinding in the brain. Multiple lines of evidence link theITGB3gene encoding the integrin β3 subunit with the serotonin (5-HT) system, likely via its modulation of the 5-HT transporter (SERT). TheITGB3coding polymorphism Leu33Pro (rs5918, PlA2) produces hyperactive αvβ3 receptors that influence whole-blood 5-HT levels and may influence the risk for autism spectrum disorder (ASD). Using a phenome-wide scan of psychiatric diagnoses, we found significant, male-specific associations between the Pro33 allele and attention-deficit hyperactivity disorder and ASDs. Here, we used knock-in (KI) mice expressing anItgb3variant that phenocopies the human Pro33 variant to elucidate the consequences of constitutively enhanced αvβ3 signaling to the 5-HT system in the brain. KI mice displayed deficits in multiple behaviors, including anxiety, repetitive, and social behaviors. Anatomical studies revealed a significant decrease in 5-HT synapses in the midbrain, accompanied by decreases in SERT activity and reduced localization of SERTs to integrin adhesion complexes in synapses of KI mice. Inhibition of focal adhesion kinase (FAK) rescued SERT function in synapses of KI mice, demonstrating that constitutive active FAK signaling downstream of the Pro32Pro33 integrin αvβ3 suppresses SERT activity. Our studies identify a complex regulation of 5-HT homeostasis and behaviors by integrin αvβ3, revealing an important role for integrins in modulating risk for neuropsychiatric disorders.

SIGNIFICANCE STATEMENTThe integrin β3 Leu33Pro coding polymorphism has been associated with autism spectrum disorders (ASDs) within a subgroup of patients with elevated blood 5-HT levels, linking integrin β3, 5-HT, and ASD risk. We capitalized on these interactions to demonstrate that the Pro33 coding variation in the murine integrin β3 recapitulates the sex-dependent neurochemical and behavioral attributes of ASD. Using state-of-the-art techniques, we show that presynaptic 5-HT function is altered in these mice, and that the localization of 5-HT transporters to specific compartments within the synapse, disrupted by the integrin β3 Pro33 mutation, is critical for appropriate reuptake of 5-HT. Our studies provide fundamental insight into the genetic network regulating 5-HT neurotransmission in the CNS that is also associated with ASD risk.
Overactivity of Liver-Related Neurons in the Paraventricular Nucleus of the Hypothalamus: Electrophysiological Findings indb/dbMice
Authors: Gao Hong , Molinas Adrien J.R. , Miyata Kayoko , Qiao Xin , Zsombok Andrea
Published: October 2017

Preautonomic neurons in the paraventricular nucleus (PVN) of the hypothalamus play a large role in the regulation of hepatic functions via the autonomic nervous system. Activation of hepatic sympathetic nerves increases glucose and lipid metabolism and contributes to the elevated hepatic glucose production observed in the type 2 diabetic condition. This augmented sympathetic output could originate from altered activity of liver-related PVN neurons. Remarkably, despite the importance of the brain-liver pathway, the cellular properties of liver-related neurons are not known. In this study, we provide the first evidence of overall activity of liver-related PVN neurons. Liver-related PVN neurons were identified with a retrograde, trans-synaptic, viral tracer in male lean anddb/dbmice and whole-cell patch-clamp recordings were conducted. Indb/dbmice, the majority of liver-related PVN neurons fired spontaneously; whereas, in lean mice the majority of liver-related PVN neurons were silent, indicating that liver-related PVN neurons are more active indb/dbmice. Persistent, tonic inhibition was identified in liver-related PVN neurons; although, the magnitude of tonic inhibitory control was not different between lean anddb/dbmice. In addition, our study revealed that the transient receptor potential vanilloid type 1-dependent increase of excitatory neurotransmission was reduced in liver-related PVN neurons ofdb/dbmice. These findings demonstrate plasticity of liver-related PVN neurons and a shift toward excitation in a diabetic mouse model. Our study suggests altered autonomic circuits at the level of the PVN, which can contribute to autonomic dysfunction and dysregulation of neural control of hepatic functions including glucose metabolism.

SIGNIFICANCE STATEMENTA growing body of evidence suggests the importance of the autonomic control in the regulation of hepatic metabolism, which plays a major role in the development and progression of type 2 diabetes mellitus. Despite the importance of the brain-liver pathway, the overall activity of liver-related neurons in control and diabetic conditions is not known. This is a significant gap in knowledge, which prevents developing strategies to improve glucose homeostasis via altering the brain-liver pathway. One of the key findings of our study is the overall shift toward excitation in liver-related hypothalamic neurons in the diabetic condition. This overactivity may be one of the underlying mechanisms of elevated sympathetic activity known in metabolically compromised patients and animal models.
Combinatorial regulation of the balance between dynein microtubule end accumulation and initiation of directed motility
Authors: Jha Rupam , Roostalu Johanna , Cade Nicholas I , Trokter Martina , Surrey Thomas
Published: October 2017

Cytoplasmic dynein is involved in a multitude of essential cellular functions. Dynein's activity is controlled by the combinatorial action of several regulatory proteins. The molecular mechanism of this regulation is still poorly understood. Using purified proteins, we reconstitute the regulation of the human dynein complex by three prominent regulators on dynamic microtubules in the presence of end binding proteins (EBs). We find that dynein can be in biochemically and functionally distinct pools: either tracking dynamic microtubule plus‐ends in an EB‐dependent manner or moving processively towards minus ends in an adaptor protein‐dependent manner. Whereas both dynein pools share the dynactin complex, they have opposite preferences for binding other regulators, either the adaptor protein Bicaudal‐D2 (BicD2) or the multifunctional regulator Lissencephaly‐1 (Lis1). BicD2 and Lis1 together control the overall efficiency of motility initiation. Remarkably, dynactin can bias motility initiation locally from microtubule plus ends by autonomous plus‐end recognition. This bias is further enhanced by EBs and Lis1. Our study provides insight into the mechanism of dynein regulation by dissecting the distinct functional contributions of the individual members of a dynein regulatory network.
Familia y escuela: dos contextos comprometidos con la formación en ciclo III de la educación básica
Authors: Pedraza Alexandra Patricia , Salazar Moreno Claudia Patricia , Robayo Arsenio Enrique , Moreno Emerson Arturo
Published: October 2017

El presente artículo se circunscribe en torno a las reflexiones que sobre las percepciones de la relación familia y escuela tienen niños que cursan el ciclo III de educación básica. Se pretende profundizar en los diferentes matices de las relaciones entre padres y docentes y en cómo dichas interacciones fortalecen o contradicen el éxito escolar.

La escuela es una institución cuyo objeto esencial es la formación del ser humano, pero dicha misión no puede consolidarse sin la participación proactiva de la institución familiar ni sin el apoyo decidido del estado y la sociedad. En torno a dichos cuestionamientos y a lo que manifiestan los estudiantes entrevistados, se teje una red de conceptos que tratan de dilucidar las coyunturas que se presentan al interior de los hogares y los vaivenes que caracterizan a la compleja relación familia y escuela.