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The dynamic gene expression from different genetic systems for protein and lysine contents of indica rice.

The dynamic expression of genes for protein and lysine contents of rice grain under different environments was carried out with time-dependent measures by using the developmental genetic models for quantitative traits of triploid endosperm in cereal crops. The results showed that the genetic effects, especially genotype x environment (GE) interaction effects from the genes expression of different genetic systems including triploid endosperm, cytoplasm and diploid maternal plant were important for the performance of both nutrient quality traits at all developmental times/stages of rice grain. The conditional genetic variance analysis found that the activation of quantitative genes especially from endosperm and maternal plant genetic systems for protein and lysine contents was gradually carried through the developmental process of rice grain. The net genetic effects showed that the new expression of quantitative genes for protein and lysine contents was more active at late filling stage (15-21 days after flowering) and maturity stage (22-28 days) of rice grain. Also the sequential expression of cytoplasmic genes cannot be ignorable for the development of nutrient quality traits. The phenomena that some genes could continuously express for several developmental stages or the genes expression could be interrupted among developmental stages of rice grain was detected especially for net endosperm additive main effects or maternal additive main effects. The differences of genetic relationships from different genetic systems were found for protein and lysine contents among developmental times of rice grain.

Diploidy↗
PubMed1989

Human brain gangliosides: developmental changes from early fetal stage to advanced age.

The developmental profiles of the four major brain gangliosides, GM1, GD1a, GD1b, and GT1b, were examined in human frontal lobe covering the period from 10 fetal weeks to 80 years of age. The ganglioside concentration increased approx. 3-fold from the 10th gestational week to the age of about 5 years. Gangliosides GM1 and GD1a increased 12-15-fold during the same period. The most rapid increase of GM1 and GD1a occurred around term, during the period for dendrite arborization, outgrowth of axons and synaptogenesis. GT1b showed a quite different developmental curve. It was the major ganglioside during the 3rd to 5th gestational month, whereafter its concentration dropped rapidly to term, from which time the concentration then increased up to 50 years of age. Similar curves were found for the other gangliosides of the b-series, GD3, GD2, GD1b and GQ1b. Ganglioside 3'-isoLM1 was a characteristic early fetal ganglioside which dropped rapidly to the 5th gestational month, reached a small peak around term and then disappeared during adulthood. The concentration of gangliosides of the neolacto series was larger than that of the lacto series during the whole developmental period. In the beginning of the second trimester, 3'-LM1 constituted 2% and LD1 10% of total ganglioside sialic acid. The new findings demonstrate more dynamic changes of the ganglioside patterns during development than noted in previous studies.

Adolescent↗
PubMed2006

Effect of Cryphonectria hypovirus 1 (CHV1) infection on Cpkk1, a mitogen-activated protein kinase kinase of the filamentous fungus Cryphonectria parasitica.

We screened Cryphonectria parasitica genomic and cDNA libraries with a probe obtained from the amplification of a conserved region among the sequence of known mitogen activated protein kinase kinases (MAPKK) and obtained genomic and cDNA clones. Sequence comparisons of the clones obtained confirmed the identification of a C. parasitica homologue to other fungal MAPKK, which we named Cpkk1. Polyclonal antibodies raised against a purified Cpkk1 fusion protein expressed in Escherichia coli were used to detect Cpkk1 protein in extracts of CHV1-infected and uninfected C. parasitica grown in liquid culture. Differences in the dynamics of phosphorylation and dephosphorylation were noticed. Under the conditions investigated, Cpkk1 protein expression is associated with active mycelial growth, before the onset of a senescent developmental stage. We hypothesize that differences in Cpkk1 phosphorylation state between CHV1 infected and virus free strains are due to a delay of the onset of the developmental stage caused by the presence of the virus.

Amino Acid Sequence↗
PubMed2004

Internet-initiated sex crimes against minors: implications for prevention based on findings from a national study.

PURPOSE: To describe the characteristics of episodes in which juveniles became victims of sex crimes committed by people they met through the Internet. METHODS: A national survey of a stratified random sample of 2574 law enforcement agencies conducted between October 2001 and July 2002. Telephone interviews were conducted with local, state, and federal law enforcement investigators concerning 129 sexual offenses against juvenile victims that originated with online encounters. RESULTS: Victims in these crimes were primarily 13- through 15-year-old teenage girls (75%) who met adult offenders (76% older than 25) in Internet chat rooms. Most offenders did not deceive victims about the fact that they were adults who were interested in sexual relationships. Most victims met and had sex with the adults on more than one occasion. Half of the victims were described as being in love with or feeling close bonds with the offenders. Almost all cases with male victims involved male offenders. Offenders used violence in 5% of the episodes. CONCLUSIONS: Health care professionals and educators, parents and media need to be aware of the existence, nature and real life dynamics of these online relationships among adolescents. Information about Internet safety should include frank discussion about why these relationships are inappropriate, criminal, and detrimental to the developmental needs of youth.

Adolescent↗
PubMed2006

Characterization of big bang, a novel gene encoding for PDZ domain-containing proteins that are dynamically expressed throughout Drosophila development.

PDZ (PSD-95, Discs-large, ZO-1) domain proteins often function as scaffolding proteins and have been shown to play important roles in diverse cellular processes such as the establishment and maintenance of cell polarity, and signal transduction. Here, we report the identification and cloning of a novel Drosophila melanogaster gene that is predicted to produce several different PDZ domain-containing proteins through alternative promoter usage and alternative splicing. This gene, that we have named big bang (bbg), was first identified as C96-GAL4, a GAL4 enhancer trap line that was generated in our lab. To further characterize bbg, its expression pattern was examined in ovaries, embryos, and late third instar larvae using UAS reporter gene constructs, in situ hybridization, or immunocytochemistry. In addition, the expression of alternatively spliced transcripts was examined in more detail using in situ hybridization. We find that during embryogenesis bbg is predominantly expressed in the developing gut, but it is also expressed in external sensory organs found in the epidermis. In the late third instar larva, bbg is expressed along the presumptive wing margin in the wing disc, broadly in the eye disc, and in other imaginal discs as well as in the brain. The expression patterns observed are dynamic and specific during development, suggesting that like other genes that encode for several different PDZ domain protein isoforms, bbg likely plays important roles in multiple developmental processes.

Alternative Splicing↗
PubMed1994

Mechanisms in the explanation of developmental change.

Despite extensive use of the term mechanism in developmental psychology, and in theories of cognitive development in particular, scant attention has been given to specification of what the concept entails. The principal aim of this paper, by focusing on its implicit assumptions, has been to detail at least one view of how mechanism should be conceptualized. As with any general concept, the illustrations of its use in selected developmental theories point to differences in the ways aspects of the concept are treated. They suggest, too, why consensus in arriving at a unified concept of mechanism has been and will continue to be difficult. Nevertheless, the following conclusions can be drawn from the foregoing conceptual analysis and the analysis of selected applications. In the explanation of the operation of a mechanism, one must assume a temporal (asymmetrical) relation of either a single set or a series of initial conditions to an event, condition, or structure denoted as an effect. The relation of the antecedent to the consequent event(s) is describable by some theory of causal explanation. Implicit in any description of mechanism, then, is a theory of causal explanation. However, a strict account of causal relations, in which necessary and sufficient conditions of causal explanation are met, is not possible in any of the sciences. In addition, adequate reference to mechanisms requires the specification of structures, whether material or immaterial, and their constituent parts, with the parts related to each other in a systematic way. Such systems of structural components are operated upon by some process or set of processes that produces particular effects. Hence, mechanism and process are not interchangeable terms, nor does mechanism underlie process. Instead, in a mechanism, structure and process are complements of each other. Among the specific models of development mechanisms examined, all provide varying notions of process, but only some are directly concerned with the specification of structure. To the extent that they omit structures they are limited in their accounts of the mechanisms they are purported to describe and explain. Neuroscience accounts of developmental change most directly confront structure-function relations. In being closely allied to biological theories, they forthrightly acknowledge structural and functional forms of causal explanation. Dynamic system theories, in contrast, in emphasizing the dynamics of change, appear to place their primary, if not sole emphasis on the functional aspects of development. Nevertheless, implicit in their accounts are references to structure, often couched in the language of organization.(ABSTRACT TRUNCATED AT 400 WORDS)

Causality↗
PubMed2000

Neuronal-glial interactions and behaviour.

Both neurons and glia interact dynamically to enable information processing and behaviour. They have had increasingly intimate, numerous and differentiated associations during brain evolution. Radial glia form a scaffold for neuronal developmental migration and astrocytes enable later synapse elimination. Functionally syncytial glial cells are depolarised by elevated potassium to generate slow potential shifts that are quantitatively related to arousal, levels of motivation and accompany learning. Potassium stimulates astrocytic glycogenolysis and neuronal oxidative metabolism, the former of which is necessary for passive avoidance learning in chicks. Neurons oxidatively metabolise lactate/pyruvate derived from astrocytic glycolysis as their major energy source, stimulated by elevated glutamate. In astrocytes, noradrenaline activates both glycogenolysis and oxidative metabolism. Neuronal glutamate depends crucially on the supply of astrocytically derived glutamine. Released glutamate depolarises astrocytes and their handling of potassium and induces waves of elevated intracellular calcium. Serotonin causes astrocytic hyperpolarisation. Astrocytes alter their physical relationships with neurons to regulate neuronal communication in the hypothalamus during lactation, parturition and dehydration and in response to steroid hormones. There is also structural plasticity of astrocytes during learning in cortex and cerebellum.

Animals↗
PubMed1995

Differential expression of alternatively spliced forms of MAP4: a repertoire of structurally different microtubule-binding domains.

We previously reported that the microtubule (MT)-binding domain of microtubule-associated protein 4 (MAP4) contains three 18-amino acid imperfect repeats that are homologous to the repeats found in the MT-binding domains of the neuronal MAPs, MAP2 and tau [Chapin, S. J., & Bulinski, J. C. (1991) J. Cell Sci. 98, 27-36]. Here we report the isolation of clones encoding additional isoforms of MAP4, which differ in the number of repeated elements contained within their MT-binding domains. In addition to clones encoding three repeats, we isolated clones encoding a four-repeat isoform, whose MT-binding domain bears a striking similarity to the four-repeat isoform of tau. Other MAP4 clones that we isolated encode five repeats. The additional repeat in the five-repeat isoform of MAP4 is quite unusual in its amino acid sequence; this unusual repeat was also found by Aizawa et al. [Aizawa, H., et al. (1990) J. Biol. Chem. 265, 13849-13855] among the repeats encoded by bovine MAP4 clones possessing four repeats. In humans, MAP4 was recently shown to be encoded by a single-copy gene [West, R. R., et al. (1991) J. Biol. Chem. 266, 21886-21896]; we demonstrated that the human MAP4 gene is located on human chromosome 3p21. Expression of multiple MAP4 isoforms from this gene, which appears to result from alternative RNA splicing, was investigated by RNase protection analysis of mammalian cell lines and rat tissues. The five-repeat isoform was the only form detectable in most cell lines, and it was the most abundant isoform expressed in rat lung, liver, kidney, spleen, and testis. However, in rat brain, heart, and skeletal muscle, although the five-repeat isoform was expressed at all developmental stages examined, the tau-like four-repeat isoform was also expressed, and its expression increased during development. The three-repeat isoform was expressed in heart and, to a lesser extent, in brain, skeletal muscle, and lung. Our results demonstrate that several different MAP4 isoforms are expressed in the rat in different tissues and at various developmental stages. Furthermore, our data suggest that differential expression of MAP4 isoforms possessing distinct MT-binding domains may be involved in the changes in MT dynamics or function that are known to accompany differentiation.

Alternative Splicing↗
PubMed1994

High-resolution, non-crystallographic structural studies of large integral membrane proteins.

The work described here clearly demonstrates that n.m.r. is a viable method with which to resolve molecular details about membrane proteins and can give information at a resolution comparable with that gained from crystallographic studies, where, in the limited number of cases studied so far, such information is available. Sensitivity is not a major problem although other difficulties may prevent particular kinds of information being resolved. However, because bond orientational details are obtained ab initio, the method is quite model independent and interpretationally unique. The requirements for solid-state n.m.r. methods to be applied to a large membrane protein are that: a sufficient amount of functionally active protein is available; the protein should be located in bilayers; and suitable specific isotopic enrichment is achieved, in ideal cases, either by chemical or biosynthetic means. Achieving these requirements will need to draw on a range of skills, possibly genetic or chemical or both, and a full understanding of the biochemistry is essential to ensure that any structural information gained is functionally relevant. The structural information potentially available includes: (a) conformation details about specific parts of a protein or its binding sites; (b) distance measurements between specific labels introduced into the protein; (c) dynamics of particular parts of the protein; (d) chain folding and residue orientation; and (e) the mechanistic changes that can occur during a functional cycle. Much developmental work still needs to be done both on the sample handling instrumental side and with the theoretical aspect of the method.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

Development of a global motor rating scale for young children (0-4 years) including eye-hand grip coordination.

A comparative study of the eight motor rating scales available in Western countries demonstrated methodological differences in the choice of items and standardization. We have developed a global motor rating scale that includes items which measure postural-motor, locomotor (PML) and eye-hand grip coordination (EHGC), and which allows the assessment of an average of motor function level (MFL), PML and EHGC development. Scores obtained were used to define the acquisition of motor age based on the skills completed. The items were selected on the basis of the average age at which the function developed in two populations of healthy full-term French infants, followed from birth to 4 months (n = 60) and from 4 months to 4 years (n = 63). Recent French developmental standards (mean age and standard deviation) of acquisition allow the identification of neuro-psychomotor deviations from normal motor behaviour. This includes both static and dynamic motor coordination sequences. Inter-examiner correlations (n = 3) for 15 randomly selected children indicated a coefficient of 0.90. The scale revealed a sequence in the organization of learned postural-motor, locomotor and eye-hand gripping skills which can contribute to the understanding of brain areas implicated in this maturation process.

Child Development↗
PubMed1998

Endogenous IL-10 regulates IFN-gamma and IL-5 cytokine production and the granulomatous response in Schistosomiasis mansoni-infected mice.

In murine Schistosomiasis mansoni circumovum, granuloma formation is regulated by pro- and anti-inflammatory cytokines. Among the latter, interleukin-10 (IL-10) has been shown to regulate the inflammatory response. In this study we examined the role of endogenously produced IL-10 in T-helper 1 (Th1)- and Th2-type cytokine production and granuloma formation. The dynamics of IL-10 production through the course of the infection were different in granuloma versus splenic cells. In the former, production peaked during the early developmental stage (6 weeks of infection) of the granuloma and then declined. In splenocytes production peaked at 12 weeks, before down-modulation of the granuloma response. In the developing granuloma both macrophages and T cells secreted IL-10. In anti-IL-10 monoclonal antibody (mAb)-supplemented granuloma cell cultures endogenous IL-10-mediated regulation of interferon-gamma (IFN-gamma) was manifest only at 6 weeks; that of IL-2 continued throughout the infection (6-20 weeks). IL-4 production was unaffected, but IL-5 production was regulated at the 6 and 8 weeks time point. Splenocytes showed regulation of IFN-gamma and IL-2 production at the peak of the granulomatous response (8 weeks). IL-4 production was not regulated, whereas IL-5 production was regulated only at 6 weeks. Repeated injections of anti-IL-10 mAb given to mice at 6, 12 or 20 weeks of the infection significantly enhanced liver and lung granuloma growth, tissue eosinophilia, and IFN-gamma, IL-5 production at the early developmental phase (6 weeks) of the lesions. Thus, in schistosome-infected mice endogenous IL-10 is shown to regulate Th1- and Th2-type cytokine production and granuloma formation during the early Th0/Th1 phase of the immune response.

Animals↗
PubMed2001

The externality of the inside: body images of pregnancy.

This paper draws on literature, empirical data and a range of theoretical perspectives on the maternal body to examine understandings of the relationship between a pregnant woman and her foetus, with a particular focus on the body images used by women to represent this relationship. Psychoanalytic and nursing accounts of the relationship between mother and foetus have often described a symbiotic 'oneness' or unity during pregnancy. Such accounts, however, stress the temporary nature of this unity and identify a series of 'stages' of separation or 'polarisation' between mother and foetus during pregnancy. In contrast, many of the 25 women who participated in our interview study of new motherhood described a confusion of the boundary between self and foetus. For many women the experience of pregnancy and the relationship with the unborn baby was ambiguous and uncertain. Importantly, none of these women described her relationship with the foetus as a series of developmental stages, but rather saw it as fluctuating throughout pregnancy. These findings are more consistent with the work of feminist theorists who describe pregnancy as a dynamic and fluid merging of the inside and the outside of the body/self.

Adult↗
PubMed1992

Postural requirements and progression velocity in young walkers.

This article describes developmental changes in gait velocity and relates these changes to gait parameters that index postural stability (step width and lateral acceleration) and two components of velocity (cadence and step length). Five children were observed longitudinally over a 2-year period after onset of independent walking. Their range of speed increased threefold in the first 6 months of independent walking and then remained constant. In contrast, step width decreased approximately twofold. Whereas in adults, cadence and step length contribute approximately equally to speed, when infants first begin to walk independently, increase in velocity is due mostly to increased step length. After 5 months of independent walking, the pattern reverses, and increase in velocity is due primarily to increased cadence. The pattern remains constant over the next 18 months. From a developmental point of view, the data lead us to interpret early walking (the first 5 months) as a process of integration of postural constraints into the dynamic necessities of gait movement. A second phase, beginning after 4 to 5 months of independent walking, is considered to be a tuning phase characterized by a more precise adjustment of the gait parameters.

Journal Article↗
PubMed2004

Regulatory roles of leptin at the hypothalamic-hypophyseal axis before and after sexual maturation in cattle.

Studies assessed, either directly or indirectly, the role of GnRH in leptin-mediated stimulation of LH release in cattle before and after sexual maturation. In experiment 1, the objectives were to determine whether leptin could acutely accelerate the frequency of LH pulses, and putatively GnRH pulses, in prepubertal heifers at different stages of development. In experiment 2, we determined directly whether acute, leptin-mediated increases in LH secretion in the fasted, mature female are accompanied by an increase in GnRH secretion. Ten-month-old prepubertal heifers (experiment 1) fed normal- (n = 5) and restricted-growth (n = 5) diets received three injections of saline or recombinant ovine leptin (oleptin; 0.2 microg/kg body weight, i.v.) at hourly intervals during 5-h experiments conducted every 5 wk until all normal-growth heifers were pubertal. Leptin increased mean concentrations of circulating LH regardless of diet, but pulse characteristics were not altered at any age. In experiment 2, ovariectomized, estradiol-implanted cows (n = 5) were fasted twice for 72 h and treated with either saline or oleptin i.v. (as in experiment 1) on Day 3 of each fast. Leptin increased plasma concentrations of LH and third ventricle cerebrospinal fluid concentrations of GnRH, and increased the amplitude of LH and the size of GnRH pulses, respectively, on Day 3 of fasting compared to saline. Overall, results indicate that leptin is unable to accelerate the pulse generator in heifers at any developmental stage. However, leptin-mediated augmentation of LH concentrations and pulse amplitude in the nutritionally stressed, mature female are associated with modifications in GnRH secretory dynamics.

Animals↗
PubMed1998

The Drosophila SOX-domain protein Dichaete is required for the development of the central nervous system midline.

SOX-domain proteins are a class of developmentally important transcriptional regulators related to the mammalian testis determining factor SRY. In common with other SOX-domain genes, the Drosophila Dichaete gene has a dynamic expression profile in the developing central nervous system, including cells of the ventral midline. We find defects in the differentiation of midline glia and concomitant axonal defects in Dichaete mutants that are rescued by driving Dichaete expression in the midline. Since Dichaete is required for the correct specification or differentiation of midline glia, we have used the ventral midline as a model system to study SOX gene function in vivo and demonstrate a genetic interaction between Dichaete and the POU domain gene ventral veinless. In mammals, a protein related to Dichaete, SOX2, also interacts with POU transcription factors. The midline phenotypes of Dichaete mutations are rescued by expression of mouse SOX2. Our data suggest that SOX gene structure, function and interactions have been conserved during evolution.

Alleles↗
PubMed1989

Cocaine, pregnancy, and the neonate.

With the increasing use of cocaine in the U.S. population, women of childbearing age have particularly shown an increasing prevalence of use. In an ongoing study at the Perinatal Center for Chemical Dependence (PCCD) at Northwestern University Medical School, 70 infants delivered to cocaine-using women were evaluated. Pregnancy and neonatal outcome were compared to a group of drug-free controls who had no history or evidence of licit or illicit drug use. These controls were selected on the basis of social, demographic, and environmental backgrounds and were comparable for cigarette use during pregnancy. The cocaine-addicted women had a high incidence of pregnancy complications, and infants born to cocaine-using women demonstrated an increased rate of intrauterine growth retardation, prematurity, microcephaly, and perinatal morbidity. Further research will begin to focus not only on the effects of cocaine per se, but also on the interactive effects of polydrug use, the dynamics of maternal/infant interaction in the substance abusing mother, and the environmental factors that place cocaine-exposed infants at high risk for future medical and developmental disabilities.

Adolescent↗
PubMed2006

Seasonal maturation of Glypthelmins vitellinophilum (Trematoda: Digenea) in Lysapsus limellus (Anura: Pseudidae) from an Argentinian subtropical permanent pond.

From December 1995 to November 2000, the seasonal maturation of Glypthelmins vitellinophilum Dobbin, 1958, in its definitive host, the frog Lysapsus limellus Cope, 1862, was studied in a subtropical permanent pond in northeastern Argentina. The objectives of this study were: 1) to determine the infrapopulation dynamics of the parasite, analyzing the seasonal maturation cycle throughout the years; and 2) to examine the relationship between the intensity of trematode infection in different developmental stages (recruitment, growth and maturation) and the host's body length. Of a total of 1,400 frogs examined over 60 months (5 years), 38% were found to be infected with G. vitellinophilum, and the intensity of infection was 1-15 trematodes per frog. Specimens of G. vitellinophilum were present in L. limellus throughout the years, but did not show a pronounced seasonal maturation cycle. Possible reasons for these findings are discussed with reference to climatic fluctuations and biotic factors. The infective period of the parasite (stage I) occurred in summer, autumn and spring, coinciding with the time each frog cohort appeared. These infections were found principally in small body sizes (classes 1 and 2) of L. limellus. Juvenile and nongravid specimens of worms (stage II and III) were found in frogs of different body sizes throughout the period of investigation. Gravid specimens of the parasite (stage IV) were generally recorded in autumn, winter and spring, mainly in the bodies of larger frogs. The body length of Trematodes in stages I and IV was significantly and positively correlated with that of the frogs.

Animals↗
PubMed2006

Hydroprene prolongs developmental time and increases mortality of Indianmeal moth (Lepidoptera: Pyralidae) eggs.

Eggs of the Indianmeal moth, Plodia interpunctella (Hübner), were exposed to the labeled rate of hydroprene (1.9 x 10(-3) mg [AI]/cm2) sprayed on concreted petri dishes. These eggs were exposed for 1, 3, 6, 12, and 18 h and until hatching (continuous exposure) at temperatures of 16, 20, 24, 28, and 32 degrees C and 57% RH until the emergence of first instars. The developmental time and egg mortality were significantly influenced by temperature and exposure periods. At 16 degrees C, hydroprene did not cause differences in developmental time when eggs were exposed for different periods. At temperatures >16 degrees C, both exposure period and temperature influenced developmental time. The maximum developmental time (15.0 +/- 0.2 d) occurred at 16 degrees C, and the minimum developmental time (3.2 +/- 0.3 d) occurred at 32 degrees C. Mortality increased when eggs were exposed to hydroprene for longer periods at all of the five tested temperatures. The greatest mortality (81.6 +/- 2.1%) occurred when eggs were continuously exposed on treated surfaces at 32 degrees C. We used developmental time instead of rate (1/ developmental time) to fit simple linear or polynomial regression models to the development data. Appropriate models for developmental time and mortality were chosen based upon lack-of-fit tests. The regression models can be used in predictive simulation models for the population dynamics of Indianmeal moth to aid in optimizing use of hydroprene for insect management.

Animals↗