Development of Valpha4+ NK T cells in the early stages of embryogenesis.

The majority of T lymphocytes start to develop at around day 15 of gestation (d15)-d17 in the thymus and comprise the peripheral repertoire characterized by the expression of polymorphic T-cell antigen receptors (TCRs). Contrary to these conventional T cells, a subset of T cells, called natural killer (NK) T cells (most of them expressing an invariant TCR encoded by the Valpha14Jalpha281 gene with a 1-nt N-region), preferentially differentiates extrathymically and dominates the peripheral T-cell population at a high frequency (5% in splenic T cells and 40% in bone marrow T cells). Here, we investigated the development of NK T cells and found that the invariant Valpha14+ TCR transcripts and the circular DNA created by Valpha14 and Jalpha281 gene rearrangements can be detected in the embryo body at d9.5 of gestation and in the yolk sac and the fetal liver at d11.5-d13.5 of gestation, but not in the thymus, whereas T cells with Valpha1+ TCR expression, a major population in the thymus, were not observed at these early stages of gestation. Fluorescence-activated cell sorter analysis also demonstrated that there exist CD3+ alpha beta+ T cells, almost all of which are Valpha14/Vbeta8+ NK+ T cells, during early embryogenesis. To our knowledge, this demonstrates for the first time that a T lymphocyte subset develops in extrathymic tissues during the early stages of embryogenesis.

Identification of a Drosophila muscle development gene with structural homology to mammalian early growth response transcription factors.

In Drosophila, stripe (sr) gene function is required for normal muscle development. Some mutations disrupt embryonic muscle development and are lethal. Other mutations cause total loss of only a single muscle in the adult. Molecular analysis shows that sr encodes a predicted protein containing a zinc finger motif. This motif is homologous to the DNA binding domains encoded by members of the early growth response (egr) gene family. In mammals, expression of egr genes is induced by intercellular signals, and there is evidence for their role in many developmental events. The identification of sr as an egr gene and its pattern of expression suggest that it functions in muscle development via intercellular communication.

Basic fibroblast growth factor can mediate the early inductive events in renal development.

The earliest characterized events during induction of tubulogenesis in renal anlage include the condensation or compaction of metanephrogenic mesenchyme with the concurrent upregulation of WT1, the gene encoding the Wilms tumor transcriptional activator/suppressor. We report that basic fibroblast growth factor (FGF2) can mimic the early effects of an inductor tissue by promoting the condensation of mesenchyme and inhibiting the tissue degeneration associated with the absence of an inductor tissue. By in situ hybridization, FGF2 was also found to mediate the transcriptional activation of WT1 and of the hepatocyte growth factor receptor gene, c-met. Although FGF2 can induce these early events of renal tubulogenesis, it cannot promote the epithelial conversion associated with tubule formation in metanephrogenic mesenchyme. For this, an undefined factor(s) from pituitary extract in combination with FGF2 can cause tubule formation in uninduced mesenchyme. These findings support the concept that induction in kidney is a multiphasic process that is mediated by more than a single comprehensive inductive factor and that soluble molecules can mimic these inductive activities in isolated uninduced metanephrogenic mesenchyme.

Examining the Complex Relationships of Early Intervention on Language and Psychosocial Development in Families Facing Multiple Risks with a Focus on Children of Hispanic Immigrants

Abundant research has shown that poverty has negative influences on young child academic and psychosocial development, and unfortunately, disparities in school readiness between low and high income children can be seen as early the first year of life. The largest federal early care and education intervention for these vulnerable children is Early Head Start (EHS). To diminish these disparate child outcomes, EHS seeks to provide community based flexible programming for infants and toddlers and their families. Given how relatively recent these programs have been offered, little is known about the nuances of how EHS impacts infant and toddler language and psychosocial development. Using a framework of Community Based Participatory Research (CBPR) this paper had 5 goals: 1) to characterize the associations between domain specific and cumulative risk and child outcomes 2) to validate and explore these risk-outcome associations separately for Children of Hispanic immigrants (COHIs), 3) to explore relationships among family characteristics, multiple environmental factors, and dosage patterns in different EHS program types, 4) to examine the relationship between EHS dosage and child outcomes, and 5) to examine how EHS compliance impacts child internalizing and externalizing behaviors and emerging language abilities. Results of the current study showed that risks were differentially related to child outcomes. Poor maternal mental health was related to child internalizing and externalizing behaviors, but not related to emerging child language skills. Although child language skills were not related to maternal mental health, they were related to economic hardship. Additionally, parent level Spanish use and heritage orientation were associated with positive child outcomes. Results also showed that these relationships differed when COHIs and children with native-born parents were examined separately. Further, unique patterns emerged for EHS program use, for example families who participated in home-based care were less likely to comply with EHS attendance requirements. These findings provide tangible suggestions for EHS stakeholders: namely, the need to develop effective programming that targets engagement for diverse families enrolled in EHS programs.

Expertise Development in Volleyball: the Role of Early Sport Activities and Players’ Age and Height

The purpose of this study was to analyse the developmental pathway of skilled and less skilled volleyball players by focusing on the quantity and type of sporting activities, as well as their age and height in comparison to peers in those experiences. Retrospective interviews were conducted to provide a longitudinal and detailed account of sport involvement of 30 skilled and 30 less skilled volleyball players (15 male and 15 female players per group) throughout different developmental stages (stage 1: 8-12 years; stage 2: 13-16 years; stage 3: 17-20 years). Results indicated that the developmental pathway of these volleyball players (i.e. skilled and less skilled) was characterized by an early diversified sport involvement with a greater participation in sport activities during stages 1 and 2. However, skilled players specialized later in volleyball (between age 14 and 15) and performed more hours of volleyball at stage 3 (from 17 years of age onwards). Also, skilled players (male and female) were younger in both the diversified sport activities and volleyball at the later stages of development (i.e. stages 2 and 3), and skilled female players were taller than peers in those activities in the early stages of development (i.e. stages 1 and 2). The present findings suggest early diversification as a feasible pathway to reach expertise in volleyball and highlight the importance of practicing with older peers once specialization in the main sport has occurred. The findings highlight the need for coaches and sport programs to consider different stimuli existing within the training environment (i.e. characteristics of athletes, such as age and height) that influence the quality of practice and contribute to players’ expertise development.

Early steps of paired fin development in zebrafish compared with tetrapod limb development.

The development of zebrafish paired fins and tetrapod forelimbs and hindlimbs show striking similarities at the molecular level. In recent years, the zebrafish, Danio rerio has become a valuable model for the study of the development of vertebrate paired appendages and several large-scale mutagenesis screens have identified novel fin mutants. This review summarizes recent advances in research into zebrafish paired fin development and highlights features that are shared with and distinct from limb development in other main animal models.

The role of the Church and the folk in the development of the early drama in New Mexico.

Thesis--Univ. of Pennsylvania.

The origin and development of early Christian church architecture.

Bibliography: p. 143-147.

The flag of the United States of America, depicting its early origin and progressive development,

Mode of access: Internet.

Manitoba : history of its early settlement, development, and resources /

Mode of access: Internet.

Early chapters in the development of the Patomac route to the West,

In three parts; pt. I-II reprinted from the Records of the Columbia historical society.

History of the Typographical union, its beginnings, progress and development, its beneficial and educational features together with a chapter on the early organization of printers.

Plate "Philadelphia typographical society," facing pl 56, accompanied by leaf with descriptive letterpress.

The early history of veterinary literature and its British development /

Vol. 1 reprinted from The Journal of comparative pathology and therapeutics, 1912-18; v. 2 from The Veterinary journal, 1923-24; v. 3 from The Veterinary journal, 1929-30.