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PubMedDate not supplied

The Surgeon General's Report and special-needs patients: a framework for action for children and their caregivers.

The Surgeon General's Report, Oral Health in America, is the first comprehensive assessment of oral, dental, and craniofacial health in the history of our nation. The intent of this first-ever Report is to alert Americans to the full meaning of oral health and its importance to general health and well-being across the lifespan. Moreover, the Report has been released at a time in human history of enormous changes as well as opportunities. The convergence of public health policies, "quality of life" expectations, global informatics, a new century of biotechnology, the completion of the Human Genome Project, changes in the management of health care, and the acknowledgment of enormous health disparities herald a call to action. These profound dynamics particularly affect children and their caregivers and the multitude of social, economic, and health issues associated with special patients and developmental disabilities. This paper will highlight the issues, provide recommendations, and suggest a call to action.

Adolescent↗
PubMed1997

Dynamics of endothelium-muscle cell contacts in the coronary artery of the dog in ontogeny.

The myo-endothelial area in the coronary artery conduit was described in 3 developmental stages: in fetuses, newborns, and adult dogs. Transmission and scanning electron microscopy were used for the study, and morphometry was used for quantitative evaluation. In all three stages, the internal elastic lamina was found to be fenestrated. Endothelial cells and smooth muscle cells (SMC) approached the fenestrae, and protrusions of one or both cells entered into the fenestrae. In some places contacts between endothelial and SMC were found. The patterns of mutual approaches of smooth muscle and endothelial cells, as well as the entering into the fenestrae were similar in all three stages. The myo-endothelial contacts were counted per 100 microns inner circumference of the coronary artery and the numbers observed, i.e. 5.17 +/- 0.50 in fetuses, 1.94 +/- 0.17 in newborns and 0.33 +/- 0.09 in adult animals, proved clearly that the frequency of myo-endothelial contacts, highest in fetuses, decreases with age. With regard to the dual control of the coronary smooth muscle and/or diameter, it is noteworthy that an opposite trend can be observed in the development of innervation of the coronary artery: the autonomic nerve fibres with varicosities are missing in the coronary wall 1 week before birth, while after birth their number keeps increasing. Remarkable enough is also the difference in distances between the endothelium and SMC on the one hand and nerve varicosities and SMC on the other. The above facts indicate a prevalence of endothelial control of coronary diameter.

Aging↗
PubMed2003

The spatiotemporal expression pattern of the bone morphogenetic protein family in rat ovary cell types during the estrous cycle.

In the mammalian ovary, great interest in the expression and function of the bone morphogenetic protein (BMP) family has been recently generated from evidence of their critical role in determining folliculogenesis and female fertility. Despite extensive work, there is a need to understand the cellular sites of expression of these important regulatory molecules, and how their gene expression changes within the basic ovary cell types through the cycle. Here we have performed a detailed in situ hybridization analysis of the spatial and temporal expression patterns of the BMP ligands (BMP-2, -3, -3b, -4, -6, -7, -15), receptors (BMPR-IA, -IB, -II), and BMP antagonist, follistatin, in rat ovaries over the normal estrous cycle. We have found that: i) all of the mRNAs are expressed in a cell-specific manner in the major classes of ovary cell types (oocyte, granulosa, theca interstitial, theca externa, corpora lutea, secondary interstitial, vascular and ovary surface epithelium); and ii) most undergo dynamic changes during follicular and corpora luteal morphogenesis and histogenesis. The general principle to emerge from these studies is that the developmental programs of folliculogenesis (recruitment, selection, atresia), ovulation, and luteogenesis (luteinization, luteolysis) are accompanied by rather dramatic spatial and temporal changes in the expression patterns of these BMP genes. These results lead us to hypothesize previously unanticipated roles for the BMP family in determining fundamental developmental events that ensure the proper timing and developmental events required for the generation of the estrous cycle.

Animals↗
PubMed1991

The regulation of the cell cycle during Drosophila embryogenesis: the transition to polyteny.

The process of polytenization plays a crucial role in Drosophila development, and most of the larval tissues are polytene. By analyzing the pattern of DNA replication in embryos pulse-labeled with BrdU, we show that many larval tissues undergo a transition to begin becoming polytene late in embryogenesis. Our results demonstrate that in these larval tissues polyteny results from a modified cell cycle, the endo cell cycle, in which there is only an S (synthesis) phase and a G (gap) phase. A key regulator of the mitotic cell cycle, the product of the string gene (the Drosophila homologue of cdc25), is not required for the endo cell cycle. The developmental regulation of the endo cell cycle is striking in that tissue-specific domains undergo polytene DNA replication in a dynamic pattern at defined times in embryogenesis. During subsequent rounds of the endo cell cycle in late embryogenesis and first instar larval development, the domains are subdivided and the temporal control is not as rigid. The length of the G phase varies among different tissues. By quantifying DNA content, we show that during the early polytene S phases the genome is not fully duplicated.

Animals↗
PubMed2004

Overview of the content of health supervision for young children: reports from parents and pediatricians.

OBJECTIVE: To describe the content of anticipatory guidance provided to parents of infants and toddlers and to identify primary areas of unmet need as reported by both parents and pediatricians. METHODS: Parent data were obtained from the National Survey of Early Childhood Health, a nationally representative sample of parents of 2068 US children aged 4 to 35 months. Pediatrician data were obtained from the Periodic Survey of Fellows, a national survey of members of the American Academy of Pediatrics. RESULTS: Parents and pediatricians tend to agree on the relative ranking of which topics are most frequently addressed. Parents and pediatricians both report that the traditional topics of preventive care--immunizations, feeding issues, and sleep patterns--are most frequently discussed, whereas topics that were more recently introduced into pediatric care related to developmental needs and family context are less commonly addressed. Parent-reported discussion of these topics include reading (discussed for 61% of children 19-35 months) and child care (discussed for 26% of children 19-35 months). Parent reports of some unmet need--defined as topics not discussed that the parent believes would have been helpful to them--affect 36% of children aged 4 to 9 months and 56% of children aged 10 to 35 months and are highest for the topics of discipline strategies and toilet training. Other specific areas of unmet need reported by at least 15% of parents are burn prevention, child care, reading, vocabulary development, and social development. Rates of unmet need vary with family characteristics and health system factors, including maternal education, race/ethnicity, and length of well-child visits. CONCLUSION: Parents and pediatricians report high rates of discussion on many topics that are critical to healthy development in the first years of life. They also identify areas of need that largely address health supervision on developmental topics. Findings indicate that additional research is needed to understand issues related to specific topic areas as well as the dynamics of personal and system factors that determine what is discussed.

Child Development↗
PubMed1990

Project T.E.A.M.S.

Project T.E.A.M.S. (Training, Education, and Management Skills: Meeting the Needs of Infants Prenatally Exposed to Drugs), funded by a training grant from the National Center on Child Abuse and Neglect, developed skilled interdisciplinary teams to support caregivers and optimize the health and environmental care of infants exposed prenatally to drugs and placed in out-of-home care. Using both didactic and clinical approaches, the 6-month program addressed the medical, developmental, environmental, and physical care needs of drug-exposed infants and toddlers; the special needs of their caregivers; and family dynamics and parenting issues. By enhancing the knowledge and skills of staff from community-based child welfare and health care agencies, this project demonstrated a training approach for enhancing the skills of professionals who serve the growing population of prenatally drug-exposed infants.

Community Health Services↗
PubMed1979

[Dietrich Geotg Kieser (1779-1862)--merely a romantic physician?].

As an adherent of Schelling Dietrich Georg Kieser (1779-1862) was an outstanding representative of the German medical romanticism. From 1812 to his death he was professor of medicine in Jena. Despite natural philosophical-speculative theories his general pathology contains dynamic views of the disease including psychosomatic opinions. The basis for this is the holism of man under the aspect of developmental history. Kieser did an eminent good work in the field of medical practice and organisation. He was the head of several clinics and from 1847 he was the first professor in Jena who only worked in the field of psychiatry. 1858 he was elected president of the Imperial Leopoldino-Carolinic German Academy of Scientists.

Botany↗
PubMed2004

More normal than not: a qualitative assessment of the developmental experiences of gay male youth.

PURPOSE: To examine gay youth experiences within the context of normal adolescent development. METHODS: Thematic analyses of interviews with 13 self-identified gay male youth, aged 16-22 years, each reporting minimal sexual identity distress, were completed. Interviews focused on: (a) descriptions of developmental changes perceived to occur for all adolescents, (b) descriptions of the participants' developmental experience, and (c) participants' direct comparisons of their perceptions of gay and nongay developmental experience. Data were analyzed by two investigators who, after initial review of the interview transcripts, developed a unified coding template to permit systematic analysis of the transcripts for recurrent themes. RESULTS: (a) Few (2 of 13) participants reported overall developmental experience markedly different from nongay peers. (b) Peer interaction was seen as the domain most different from that of nongay peers. (c) Open gay self-identification altered, generally positively, all peer interaction. (d) Increased peer interaction enhanced maturity in other domains. (e) Family dynamics were not substantively altered by open gay self-identification. (f) Middle and high school were identified as relatively hostile environments in which to openly identify as gay, affecting the timing and the extent of self-disclosure. (g) Developmental progress showed asynchrony across developmental domains. CONCLUSION: General developmental dysfunction is not inevitable for gay adolescents, nor is identifiable personal or family pathology directly related to sexual identity.

Adaptation, Psychological↗
PubMed2005

Arf6 modulates the beta-actin specific capping protein, betacap73.

Recent work from our laboratory has revealed that isoactin cytoskeletal and membrane dynamics are coordinately regulated. In this chapter, we review some of the recent and relevant scientific literature focusing on key aspects of cytoskeletal and membrane-mediated signal transduction. Additionally, we highlight some of the strategic molecular, biochemical, and cell-based methodologies that we have either developed or implemented in our efforts aimed at revealing the pivotal role(s) that the actin isoforms play in controlling cell shape and motility during developmental and/or disease-associated events. Furthermore, we address the central position of beta-actin and its barbed end-specific capping protein, betacap73, in modulating nonmuscle cell membrane dynamics and cell migration. In studying the molecular mechanisms mediating these cytoskeletal protein interactions, we have recently recognized that cell motility and beta-actin dynamics are controlled by the direct association of betacap73 with the plasma membrane- and endosome-associated protein, ADP-ribosylation factor 6 (Arf6).

ADP-Ribosylation Factor 6↗
PubMed2001

Infection dynamics of Hemolivia mariae in the sleepy lizard Tiliqua rugosa.

The blood parasite Hemolivia mariae was experimentally transmitted to lizards under laboratory and field conditions. Weekly blood samples from experimentally infected lizards were used to demonstrate the changes in composition of the different developmental stages of the parasite as infection progressed. The prepatent period and time to peak infection was longer for field-infected lizards compared to those held under laboratory conditions. Infections in naturally infected field lizards had longer pre-patent periods and lower mean-peak parasitaemia than those in lizards that were uninfected at the time of experimental infection. The results are discussed in relation to the natural field-transmission dynamics of H. mariae in its lizard and tick hosts.

Animals↗
PubMed2005

Solution structure and backbone dynamics of the KH-QUA2 region of the Xenopus STAR/GSG quaking protein.

The Quaking protein belongs to the family of STAR/GSG domain RNA-binding proteins and is involved in multiple cell signalling and developmental processes in vertebrates, including the formation of myelin. Heteronuclear NMR methods were used to determine the solution structure of a 134 residue fragment spanning the KH and QUA2 homology regions of the Quaking protein from Xenopus laevis (pXqua) in the absence of RNA. The protein is shown to adopt an extended type I KH domain fold that is connected to a structured alpha-helix in the C-terminal QUA2 region by means of a highly flexible linker. A comparison with the solution structure of the related protein splicing factor 1 (SF1) indicates that most aspects of the RNA-binding interface are conserved in pXqua, although the "variable loop" region that follows the second beta-strand possesses two additional alpha-helices. The structure of pXqua provides an appropriate template for building models of important homologues, such as GLD-1 and Sam68. Measurements of the (15)N relaxation parameters of pXqua confirm that the polypeptide backbone of the QUA2 region is more dynamic than that of the KH portion, and that the C-terminal helix is partially structured in the absence of RNA. By comparison with a random coil reference state, the nascent structure in the QUA2 region is estimated to contribute 15.5kJmol(-1) to the change in conformational free energy that occurs on forming a complex with RNA. Since STAR/GSG proteins may regulate alternative splicing by competing with SF1 in the nucleus for specific branch-point sequences that signal intronic RNA, the formation of secondary structure in the QUA2 region in the unbound state of pXqua has important functional consequences.

Amino Acid Sequence↗
PubMed2006

Dynamic expression of sparc precedes formation of skeletal elements in the Medaka (Oryzias latipes).

Sparc is a secreted calcium-binding glycoprotein that regulates mineralization of bone tissues in mammals. In other vertebrates, its function remains largely unclear. Here, we describe the isolation, genomic organization and expression of the sparc gene in the teleost Medaka (Oryzias latipes), an established vertebrate model for developmental studies. During earliest stages of Medaka embryogenesis, sparc is expressed in the sclerotome compartment of the somites that gives rise to precursor cells of the axial skeleton. Importantly, in this area its expression precedes that of twist-1, which is a crucial regulator of osteoblast formation. Dynamic expression is also found in the floor plate of the neural tube and the notochord. Both structures are passed by migrating skeletal precursors shortly before they differentiate and form the vertebrae. In general, sparc is expressed before the formation and mineralization of bone elements and expression of bone markers like collagen type 1a in the fins and axial skeleton of Medaka embryos. It is also expressed in several non-skeletal tissues of embryos and adult fish, suggesting possible other functions not related to bone mineralization. Taken together, the Medaka sparc gene represents an excellent marker for early sclerotome development. Its restricted and highly dynamic expression suggests a novel function during migration of sclerotome cells and their differentiation into early vertebrae. This marker thus allows the analysis of early skeletal development and formation of extracellular bone matrix in this vertebrate model.

Amino Acid Sequence↗
PubMed2005

Polar distribution dynamics of Con A binding sites in embryo sacs is temporally coupled by the fertilization process.

The binding site distribution of concanavalin agglutinin (Con A) and wheat germ agglutinin (WGA) on embryo sacs at various developmental stages of Torenia fournieri L was studied by using a cooled Charge Coupled Device (CCD) and fluorescent Con A and WGA probes. The distribution patterns of Con A and WGA binding sites on embryo sacs changed during the fertilization process. The fluorescent signal indicating Con A binding sites was distributed evenly on the surface of the embryo sac wall before anthesis, was much denser on the micropylar end of the embryo sac wall and looked like a corona on the day of anthesis. After pollination, stronger fluorescence was present on the micropylar end of the embryo sac wall and the filiform apparatus (FA), showing an obvious polar distribution. When the pollen tube entered the embryo sac and reached a synergid, the fluorescence was still concentrated on the micropylar end and FA, and started to appear on the synergid. After fertilization, the polar distribution of the fluorescence gradually disappeared and an even distribution pattern was observed again on the embryo sac wall. These results revealed that the dynamic distribution of Con A binding sites was temporally coupled with the process of fertilization. WGA binding site distribution on the embryo sac was also investigated and showed a simple pattern but also regularly changed during the process of fertilization. The variation of these lectin binding sites during the fertilization process suggests that lectin binding site interactions may play a role in the process.

Binding Sites↗
PubMed2003

Psychosocial effects of intensive care on infants and families after discharge.

The neonatal intensive care environment exposes the developing immature newborn to many sources of stress and pain at a time when the infant is developmentally least able to cope with it. Animal and human evidence suggest that effects of stress, mediated through permanent changes in the brain and neuroendocrine responses, may result in changes in behaviour and information processing, which persist throughout childhood. These changes impact on the dynamics of the mother infant dyad and infant learning. Interactional styles arising in the newborn period tend to persist throughout childhood but may be amenable to intervention focusing on maternal recognition of infant cues, social stimulation of the infant, and family integration. Developmental care may promote better family, infant and child outcomes by both reducing neonatal stress and its neurobiological sequelae, and fostering an appropriate interactional relationship between mother and infant.

Aftercare↗
PubMed2005

Food insecurity affects school children's academic performance, weight gain, and social skills.

Food insecurity has been associated with diverse developmental consequences for U.S. children primarily from cross-sectional studies. We used longitudinal data to investigate how food insecurity over time related to changes in reading and mathematics test performance, weight and BMI, and social skills in children. Data were from the Early Childhood Longitudinal Study-Kindergarten Cohort, a prospective sample of approximately 21,000 nationally representative children entering kindergarten in 1998 and followed through 3rd grade. Food insecurity was measured by parent interview using a modification of the USDA module in which households were classified as food insecure if they reported > or =1 affirmative response in the past year. Households were grouped into 4 categories based on the temporal occurrence of food insecurity in kindergarten and 3rd grade. Children's academic performance, height, and weight were assessed directly. Children's social skills were reported by teachers. Analyses examined the effects of modified food insecurity on changes in child outcomes using lagged, dynamic, and difference (i.e., fixed-effects) models and controlling for child and household contextual variables. In lagged models, food insecurity was predictive of poor developmental trajectories in children before controlling for other variables. Food insecurity thus serves as an important marker for identifying children who fare worse in terms of subsequent development. In all models with controls, food insecurity was associated with outcomes, and associations differed by gender. This study provides the strongest empirical evidence to date that food insecurity is linked to specific developmental consequences for children, and that these consequences may be both nutritional and nonnutritional.

Attitude to Health↗
PubMed1996

Molecular mechanisms of hemoglobin switching.

The developmental regulation of the human beta-globin cluster embodies all aspects of transcriptional control of eukaryotic genes. The cis-acting sequences within the cluster, distal regulatory regions and trans-acting factors all contribute to provide stringent temporal and tissue-specific expression. This review will examine the individual regulatory mechanisms which govern globin gene expression and highlight recent advances which expand our understanding of these dynamic interactions.

Amino Acid Sequence↗
PubMed2005

Evi-1 expression in Xenopus.

The Evi-1 gene was first identified as a site for viral integration in murine myeloid leukemia. Evi-1 is a zinc finger transcription factor that has been implicated in the development of myeloid neoplasia. In humans, disruption of the Evi-1 locus, by chromosomal rearrangements, is associated with myeloid leukemia and myelodyplastic syndromes. Here, we report the cloning and developmental pattern of expression of Xenopus Evi-1. xEvi-1 is expressed during oogenesis and during embryonic development. In situ hydridization reveals that xEvi-1 has a dynamic expression profile during early embryonic development. Expression of Evi-1 is detected by in situ hybridization in the pronephric tissue, the brain and in neural crest derivatives of the head and neck.

Amino Acid Sequence↗
PubMed2003

Developmental changes in plasma leptin and hypothalamic leptin receptor expression in the rat: peripubertal changes and the emergence of sex differences.

Leptin, the peptide hormone product of the ob gene, regulates food intake and energy expenditure at the hypothalamic level via the long-form of the leptin receptor (Ob-Rb). Leptin also plays a key role in determining the onset of puberty, but there is controversy as to whether leptin provides a trigger for puberty or is a permissive signal. Thus, although leptin administration can advance puberty onset in rodents, circulating leptin appears stable across puberty. While these data suggest a permissive role for leptin in rat puberty, it is possible that a change in hypothalamic response to leptin (e.g. via increased Ob-Rb expression) could enhance leptin action and thus trigger puberty without a rise in circulating leptin. In the present study we assessed developmental changes in hypothalamic Ob-Rb mRNA and protein expression in female and male rats from late fetal to postpubertal life. Quantitative RT-PCR showed that Ob-Rb mRNA increased (P<0.05) by around fivefold from fetal to postpubertal life in both females and males. These increases in Ob-Rb mRNA expression were gradual, but did not increase significantly between postnatal day 30 (pre-puberty) and day 51 (post-puberty). By day 51, hypothalamic Ob-Rb mRNA expression was higher (P<0.05) in females relative to males. Hypothalamic Ob-Rb protein showed a comparable developmental pattern (approximate threefold increase from fetal to postpubertal life), although a significant increase (15%; P<0.05) was observed between days 30 and 51 in females. Plasma leptin levels exhibited a dynamic pattern in both male and female rats during the prepubertal period, characterised by a precipitous fall after birth, relative stability to day 5, then a rapid increase to a transient peak on day 12. Plasma leptin then remained unchanged from day 15 in female rats but increased in males after puberty, thus confirming the well-recognised sex difference in adult rat leptin levels. In conclusion, this study shows that developmental increases occur not only in plasma leptin but also in hypothalamic Ob-Rb expression, suggesting that both are likely to influence the timing of puberty onset. Moreover, our data show that sex differences in both hypothalamic Ob-Rb and plasma leptin emerge only after puberty.

Animals↗