bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fertilisation competence of bovine normally matured or aged oocytes derived from different antral follicles: morphology, protein synthesis, H1 and MBP kinase activity
Authors: Pavlok Antonín , Kaláb Petr , Bobák Petr 
Published: September 2008

SummaryWe have investigated the fertilisation competence, protein synthesis, histone H1 kinase and myelin basic protein (MBP) kinase activities in three categories of bovine oocytes (derived from three size categories of follicles: M–medium, 2.5–5.0 mm; S–small, 1.5–2.5 mm; T – tiny, 1.0–1.5mm). In contrast to more or less normal meiotic maturation (85.6%) and fertilisation (70.8%) of M oocytes cultured for 24h, the fertilisation of M oocytes cultured for 40h was associated with increased rates of retarded male pronuclear development and retention of the second polar body. The S and T oocytes cultured for 24h or 40h were mostly arrested at defective late diakinesis - metaphase I (77.5–100%) stage. After fertilisation of S and T oocytes cultured for 24h no polar body was extruded and formation of one, three or four female pronuclei, together with mostly normal male pronuclei, was observed. The fertilisation of S and T oocytes after 40h culture resulted in a higher number of female and a decreased number of male pronuclei. A major change in the pattern of protein synthesis was associated with the resumption of meiosis. There were no significant differences in the profile of protein synthesis between oocyte categories in all groups either matured or fertilised. The H1 kinase activity reached comparable increased levels in oocytes of all categories matured for 24h and decreased during the 40h culture, most significantly in M oocytes. The MBP kinase activity was at approximately the same high level in all categories of oocytes after 24h of culture and remained stable until 40h. The fertilisation after 24h of culture resulted, in M oocytes, in low levels of both H1 and MBP kinase activities; in S oocytes, only H1 kinase was completely inactivated while MBP kinase activity decreased to some extent; in T oocytes, both H1 and MBP kinase activity decreased. Fertilisation of all oocyte categories after 40h culture resulted in complete inactivation of both these kinases to their basal levels.
Glycine and methionine transport by bovine embryos
Authors: Guyader-Joly Catherine , Khatchadourian Chaqué , Ménézo Yves 
Published: September 2008

SummaryAs glycine is one of the most concentrated amino acids in the female genital tract, we investigated its uptake by bovine in vitro matured/in vitro fertilised blastocysts in the presence of increasing concentrations of radiolabelled glycine. We also determined methionine uptake by in vitro and in vivo produced embryos. In our study, the hypothesis of more than one site of enzyme activity for glycine substrate was not validated. We determined a Vmax of 23.4fmol/min per embryo and a Km value of 13.3μM. No significant difference was observed either between in vivo and in vitro derived embryos or between grade 1 and grade 2 embryos for methionine uptake. The methionine and glycine uptake of a day 7 bovine was similar to that of a day 4 mouse blastocyst. This is rather low if we consider the relative cell numbers.
The behaviour of mitochondria and cell integration during somatic hybridisation of sister blastomeres of the 2-cell mouse embryo
Authors: Sekirina G.G. , Bogoliubova N.A. , Antonova N.V. , Dyban A.P. 
Published: September 2008

SummaryThe capacity of sister blastomeres of mouse embryos for induced fusion changed during the 2-cell stage. It was at low level (24%) at the early 2-cell stage, increased and reached 98.5% at the middle 2-cell stage and fell sharply to 31% at the late 2-cell stage. At the time corresponding to the G2/Mphase of the cell cycle the blastomeres fused in only 8% of cases. Vital staining of 2-cell embryos by rhodamine 123 showed that the mitochondria were dispersed throughout the cytoplasm with a ringlike (around the nucleus) or spot-like (over the metaphase plate) concentration in the centre of each blastomere. At the periphery of blastomeres the mitochondrial content was low. The behaviour of the mitochondria reflected the subsequent events of structural and functional integration of the sister blastomeres under induced fusion: a discernible boundary between partners during 30 min after electrofusion or 1 h after fusion with polyethylene glycol; movement of the two ‘rings’ to the centre of the blastomere fusion products (BFP) to form one large bright ‘spot’ over the common metaphase plate; mitochondria outlining the shape of the spindle and connection between sister blastomeres until completion of the first mitosis of BFP The data obtained suggest that fusion of the blastomeres does not lead to extensive changes in the hybrid cytoplasm and integration of nuclear material is taking place only at metaphase stage Cytogenetic examination of BFP at the 2-cell stage confirmed reconstruction of the tetraploid embryos and found that sister blastomeres of such embryos could asynchronously enter the next cleavage division similarly to normal diploid 2-cell embryos.
Chromosomes of mouse primary spermatocytes undergo meiotic divisions after incorporation into homologous immature oocytes
Authors: Ogura Atsuo , Wakayama Teruhiko , Suzuki Osamu , Shin Tae-Young , Matsuda Junichiro , Kobayashi Yoshiro 
Published: September 2008

SummaryThe primary spermatocytes used were male germ cells at prophase I. The present study was undertaken to see whether bivalent chromosomes of mouse primary spermatocytes can undergo meiotic divisions within maturing oocytes and participate in subsequent embryonic development. Primary spermatocytes (pachytene to diplotene) freshly collected from the testes of mature males were electrofused with immature oocytes shortly before or after germinal vesicle breakdown. After culture in MEM-α medium for 15 h, most (> 90%) of the oocytes containing spermatocyte chromosomes underwent maturation and arrested at metaphase II (Mil). Among 23 Mil oocytes examined, 17 (74%) had one group of chromosomes and one polar body, indicating that male chromosomes had intermingled with those of the females and completed the first meiotic division. Chromosome analyses of these Mil oocytes demonstrated their diploidy. The metaphase chromosomes were transferred to enucleated Mil oocytes freshly recovered from superovulated mice. After artificial activation, the reconstructed Mil oocytes resumed meiosis and developed to the morula/blastocyst stage. However, no pups were born following embryo transfer into recipient females. These findings indicate that the chromosomes of primary spermatocytes undergo meiotic divisions in maturing oocytes and participate in the formation of diploid embryos.
Transformation of sperm nuclei into metaphase chromosomes in maturing pig oocytes penetratedin vitro
Authors: Wang Wei-Hua , Niwa Koji 
Published: September 2008

SummaryCumulus-free pig oocytes at the germinal vesicle (GV) stage were incubated in modified Brackett & Oliphant's medium with 5% fetal calf serum and 5mM caffeine with or without cryopreserved, ejaculated spermatozoa. When oocytes were transferred into modified tissue culture medium (TCM- 199B at pH 7.4) supplemented with 1OIU/ml eCG, 1OIU/ml hCG and 1 μg/ml oestradiol-17p after 8h of incubation with spermatozoa and cultured for 0–48 h, 86–99% of oocytes were penetrated. Most (95–100%) oocytes penetrated 0–16 h after transfer had decondensed sperm chromatin. However, 24 h after transfer 47% and 33% of penetrated oocytes contained recondensed sperm chromatin and sperm metaphase chromosomes, respectively. The proportion of penetrated oocytes containing sperm metaphase chromosomes increased after 36–48 h of transfer (51–65%). The transformation of sperm nuclei to metaphase chromosomes was obtained in 75% and 79% of anaphase I (AI) to telophase I (TI) and metaphase II (Mil) oocytes, respectively, but only in 38% of metaphase I (MI) oocytes. Moreover, such transformation was observed only in 1 of 30 oocytes at the stages of GV breakdown to prometaphase I and none of 69 oocytes at the GV stage. The transformation of sperm nuclei into metaphase chromosomes was completely inhibited in oocytes penetrated by eight or more spermatozoa. Well-developed male and female pronuclei were observed in only 3 (4%) of 77 oocytes penetrated 48 h after transfer. The proportion of oocytes reaching Mil was greatly inhibited by sperm penetration; only 18% of penetrated oocytes, but 87% of non-inseminated oocytes, reached Mil by 48 h after transfer. None of the oocytes penetrated by seven or more spermatozoa reached MIL Most (75%) oocytes were inhibited from the transition from MI to Mil even though they were cultured for 48 h. The present results indicate that: (1) the cytoplasm of maturing oocytes possesses an activity for transforming sperm nuclei into metaphase chromosomes, (2) immature pig oocytes penetrated by spermatozoa can undergo meiotic maturation to MI, and (3) the transition of such oocytes from MI to Mil is inhibited, suggesting that an activity of mitogen-activated protein kinase may be retarded.
Use of chemically defined system for the direct comparison of inner cell mass and trophectoderm distribution in murine, porcine and bovine embryos
Authors: Fuente Rabindranath de la , Allan King W. 
Published: September 2008

SummaryThe mammalian blastocyst comprises an inner cell mass (ICM) and a trophectoderm cell layer. In this study the allocation of blastomeres to either cell lineage was compared between murine, porcine and bovine blastocysts. Chemical permeation of trophectoderm cells by the Ca2+ionophore A23187 in combination with DNA-specific fluorochromes resulted in the differential staining of trophectoderm and ICM. Confocal microscopy confirmed the exclusive permeation of trophectoderm and the internal localisation of intact ICM cells in bovine blastocysts. Overall, differential cell counts were obtained in approximately 85% of the embryos assessed. Mean (±SEM) total cell numbers were 72.2 ± 3.1 and 93.1±5 forin vivoderived murine (n= 41) and porcine (n= 21) expanded blastocysts, respectively. Corresponding ICM cell number counts revealed ICM/total cell number ratios of 0.27 and 0.21, respectively. Comparison ofin vivo(n= 20) andin vitroderived bovine embryos on day 8 (n= 29) or day 9 (n= 29) revealed a total cell number of 195.25±9.9, 166.14±9.9 and 105±6.7 at the expanded blastocyst stage with corresponding ICM/total cell ratios of 0.27, 0.23 and 0.23, respectively. While total cell numbers differed significantly among the three groups of bovine embryos (p<0.05), the ICM/total cell ratio did not. These results indicate that a similar proportion of cells is allocated to the ICM among blastocysts of genetically divergent species.
Inositol triphosphate receptors in sea urchin sperm
Authors: Zapata Otilia , Ralston James , Beltraán Carmen , Parys Jan B. , Chen Ji Long , Longo Frank J. , Darszon Alberto 
Published: September 2008

SummaryInositol 1,4,5-triphosphate (Ins(1,4,5)P3) is a second messenger that regulates Ca2+channels in many important cell signalling pathways. In sea urchin sperm the outer investment of the egg triggers the acrosome reaction (AR) that involves Ins(1,4,5)P3production and the opening of two Ca2+channels. Here we have sought to identify a high-affinity Ins(1,4,5)P3receptor inStrongylocentrotus purpuratussperm. An Ins(1,4,5)P3binding component was affinity-purified 12-fold from sperm extracts. It displayed similar characteristics to the Ins(1,4,5)P3receptor from other sources: pH-dependent high affinity for Ins(1,4,5)3(KD=261 nM), a τ1/2of association and dissociation of 50 and 40s, respectively, specificity (IC)50>5μMfor Ins (1)P1, Ins(1,4)P2and Ins(1,3,4,5 P4), and pharmacological sensitivity 10 and 100μ heparin/ml inhibited 75% and 100% binding respectively). An antibody against the carboxy-terminal of the type I Ins(1,4,5)P3receptor of somatic cells recognised a Plasma membrane component in the sperm head and less intensely in the flagella. This antibody also recongnised a 240 kDa band from isolated head plasma membranes, and weakly in flagellar membrane. This IP3receptor-like protein may mediate the sustained uptake of Ca2+through the second Ca2+chanel opened during the AR.
Blastocoele formation and cell allocation to the inner cell mass and trophectoderm in haploid and diploid pig parthenotes developingin vitro
Authors: Kim Nam-Hyung , Uhm Sang Jun , Ju Jin Young , Lee Hoon Taek , Chung Kil Saeng 
Published: September 2008

SummaryThe objective of this study was to determine developmental pattern and cell allocation to the inner cell mass and trophectoderm in haploid and diploid embryos following parthenogenetic activation.In vitromatured porcine oocytes were activated by ethanol treatment and cultured in the presence or absence of cytochalasin B for 5h. The oocytes were then cultured in the NCSU23 for 9 days. The combined treatment with cytochalasin B following ethanol treatment did not increase (p>0.1) the incidence of activation. The incidence of development to the blastocyst stage was higher (p<0.05) in the combined treatments of ethanol and cytochalasin B as compared with ethanol treatment alone. The percentage of oocytes with two female pronuclei was higher (p< 0.01) in oocytes treated with cytochalasin B than that in ethanol treatment alone. Treatment with both ethanol and cytochalasin B increased (p<0.01) the incidence of diploid chromosome spread over just the ethanol treatment alone. The average numbers of total cells and inner cell mass were significantly reduced (p<0.05) in the ethanol treatment alone as compared with the combined cytochalasin B and ethanol treatment. These results suggested that the ploidy may affect blastocoele formation and cell allocation to inner cell mass and trophectoderm in the pig.
Reading Trajectories of Children With Language Difficulties From Preschool Through Fifth Grade
Authors: Skibbe Lori E. , Grimm Kevin J. , Stanton-Chapman Tina L. , Justice Laura M. , Pence Khara L. , Bowles Ryan P. 
Published: September 2008

PurposeThe current work examined which theory of reading development, thecumulative reading trajectoryor thecompensatory trajectory of development,most accurately represents the reading trajectories of children with language difficulties (LD) relative to their peers with typical language (TL) skills. Specifically, initial levels of reading skills, overall rate of growth, and patterns of growth were examined.MethodChildren were classified according to whether or not they exhibited LD at 54 months of age (LDn= 145; TLn= 653), using data from the National Institute of Child Health and Human Development’s Early Child Care Research Network (see NICHD, 1993). A latent shape growth curve model was used to model reading skills at 4 time points from preschool through fifth grade.ResultsIn comparison to children with TL, children with LD showed lower reading skills in preschool, but their overall reading growth was faster. All children developed the skills associated with reading more rapidly at earlier ages compared to later ages. Children with LD continued to exhibit reading skills that were substantially lower than those of children with TL during fifth grade.ConclusionResults supported the compensatory trajectory of development. Speech-language pathologists are encouraged to adopt evidence-based practices in order to boost reading outcomes for children with LD beginning in preschool.
Developing Treatment for Adolescents Who Stutter: A Phase I Trial of the Camperdown Program
Authors: Hearne Anna , Packman Ann , Onslow Mark , O’Brian Sue 
Published: September 2008

PurposeTo investigate in detail how adolescents who stutter perform during treatment, with the aim of informing treatment development for this age group.MethodThe Camperdown Program was conducted with 3 adolescents who stutter. Their performance during treatment was recorded in detail, and outcome measures were collected before treatment and on 5 occasions after treatment.ResultsOne participant responded extremely well to treatment, with percentage of syllables stuttered (%SS) scores at 12 months follow-up around 1%. In addition, his speech naturalness was within normal limits. Another participant withdrew from treatment during maintenance, yet he still approximately halved his pretreatment %SS scores and was also sounding natural after treatment. This participant was satisfied with his treatment outcome. A third participant did not reach maintenance and did not benefit from the treatment.ConclusionThe adolescent who succeeded in treatment presented with a high level of self-confidence and maturity. When examining the factors that seemed to impact on treatment outcome, an underlying theme of decreased parent influence and increased peer influence and self-direction was detected. These are fundamental during the journey through adolescence from childhood to adulthood. Future directions in developing treatments for adolescents are discussed.
Integrating American Indian/Alaska Native Culture Into Shared Storybook Intervention
Authors: Inglebret Ella , Jones Carla , Pavel D. Michael 
Published: September 2008

PurposeThe purpose of this clinical exchange is to provide information for speech-language pathologists (SLPs) so they will be able to provide culturally responsive intervention for young children of American Indian and Alaska Native heritage. The focus is on a particular strategy–the integration of culturally based stories into shared storybook intervention.MethodThe use of culturally based stories is presented as it relates to sociocultural theory and the expressed priority of Native peoples to revitalize their cultural teaching and learning practices, inclusive of storytelling. Strategies are presented that SLPs can follow in preparing for the use of culturally based stories, as well as in ensuring that the stories that are selected for use are authentic and appropriate for the children involved. The strategies discussed represent the collaborative efforts of Native and non-Native professionals to link a review of pertinent scholarly literature with ancestral knowledge that is derived from tribal elders and tradition bearers of the Southern Puget Salish peoples. The article concludes by illustrating the application of these strategies to a program involving young children of culturally and linguistically diverse backgrounds.ConclusionSLPs can integrate culturally based stories into their language and literacy intervention to encourage American Indian and Alaska Native children.
The Use of Conversational Repairs by African American Preschoolers
Authors: Stockman Ida J. , Karasinski Laura , Guillory Barbara 
Published: September 2008

PurposeThis study aimed to describe the types and frequency of conversational repairs used by African American (AA) children in relationship to their geographic locations and levels of performance on commonly used speech-language measures.MethodThe strategies used to initiate repairs and respond to repair requests were identified in audiovisual records of spontaneous speech sampled from 120 Head Start students in Michigan (n= 69) and Louisiana (n= 51) at 3 years of age. The 30–40-min samples were elicited with common stimuli and activities while the children interacted with an adult examiner.ResultsAll participants initiated repairs and responded to examiner requests for conversational repairs. Some repair strategies were observed more often than others. The frequency, but not the types, of some of the strategies used varied significantly with participant location and level of speech-language performance.ConclusionAA children used the same types of conversational repair strategies that have been observed among young speakers of Standard English varieties.Clinical ImplicationUse of conversational repairs should be included among the pragmatic behaviors expected for 3-year-old AA children.
Bayesian learning of biological pathways on genomic data assimilation
Authors: Yoshida Ryo , Nagasaki Masao , Yamaguchi Rui , Imoto Seiya , Miyano Satoru , Higuchi Tomoyuki 
Published: September 2008

AbstractMotivation: Mathematical modeling and simulation, based on biochemical rate equations, provide us a rigorous tool for unraveling complex mechanisms of biological pathways. To proceed to simulation experiments, it is an essential first step to find effective values of model parameters, which are difficult to measure from in vivo and in vitro experiments. Furthermore, once a set of hypothetical models has been created, any statistical criterion is needed to test the ability of the constructed models and to proceed to model revision.Results: The aim of our research is to present a new statistical technology towards data-driven construction of in silico biological pathways. The method starts with a knowledge-based modeling with hybrid functional Petri net. It then proceeds to the Bayesian learning of model parameters for which experimental data are available. This process exploits quantitative measurements of evolving biochemical reactions, e.g. gene expression data. Another important issue that we consider is statistical evaluation and comparison of the constructed hypothetical pathways. For this purpose, we have developed a new Bayesian information–theoretic measure that assesses the predictability and the biological robustness of in silico pathways.Availability: The FORTRAN source codes are available at the URL http://daweb.ism.ac.jp/~yoshidar/GDA/Supplementary information: Supplementary data are available at Bioinformatics online.Contact: yoshidar@ism.ac.jp
Searching protein structure databases with DaliLite v.3
Authors: Holm L. , Kääriäinen S. , Rosenström P. , Schenkel A. 
Published: September 2008

Abstract
The Red Queen said, ‘It takes all the running you can do, to keep in the same place.’ Lewis Carrol
Motivation: Newly solved protein structures are routinely scanned against structures already in the Protein Data Bank (PDB) using Internet servers. In favourable cases, comparing 3D structures may reveal biologically interesting similarities that are not detectable by comparing sequences. The number of known structures continues to grow exponentially. Sensitive—thorough but slow—search algorithms are challenged to deliver results in a reasonable time, as there are now more structures in the PDB than seconds in a day. The brute-force solution would be to distribute the individual comparisons on a massively parallel computer. A frugal solution, as implemented in the Dali server, is to reduce the total computational cost by pruning search space using prior knowledge about the distribution of structures in fold space. This note reports paradigm revisions that enable maintaining such a knowledge base up-to-date on a PC.
Availability: The Dali server for protein structure database searching at http://ekhidna.biocenter.helsinki.fi/dali_server is running DaliLite v.3. The software can be downloaded for academic use from http://ekhidna.biocenter.helsinki.fi/dali_lite/downloads/v3.
Contact: liisa.holm@helsinki.fi