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Developmental Processes (developmental + process)
Kinds of Developmental Processes Selected AbstractsGenetic factors involved in the development of Helicobacter pylori -related gastric cancerCANCER SCIENCE, Issue 11 2006Nobuyuki Hamajima Developmental process to gastric cancer by Helicobacter pylori infection consists of three steps: (1) H. pylori infection; (2) gastric atrophy development; and (3) carcinogenesis. In each step, genetic traits may influence the process, interacting with lifestyle. In the step of H. pylori infection, two lines of genetic polymorphisms were assumed: one influencing gastric acid inhibition interacting with smoking, and the other concerning innate immune response attenuation. The former includes functional polymorphisms of IL-1B (C-31T or tightly linked T-511C), and TNF-A (T-1031C and C-857T), and the latter possibly includes NQO1 C609T. In the step to gastric atrophy, polymorphisms pertaining to the signal transduction from cytotoxin-associated gene A (PTPN11 A/G at intron 3) and to T-cell responses (IL-2 T-330G and IL-13 C-1111T) were hypothesized. There are a limited number of epidemiological genotype studies on the final step of literal carcinogenesis, potentially interacting with smoking, a low vegetable and fruit intake, and salty foods, the well-documented risk factors. In past case-control studies on the associations between genotype and gastric cancer risk, the cases consisted of H. pylori -related and unrelated gastric cancer patients and the controls consisted of individuals including the uninfected (H. pylori unexposed and exposed) and the infected with and without gastric atrophy. Accordingly, it was not clear whether the observed risk was for H. pylori -related or -unrelated gastric cancer, nor which step was involved in the observed associations even when nearly all cases were H. pylori -related. In order to elucidate the genetic traits of H. pylori -related gastric cancer, stepwise evaluation will be required. (Cancer Sci 2006; 97: 1129,1138) [source] SELF-CONTROL, SOCIAL BONDS, AND DESISTANCE: A TEST OF LIFE-COURSE INTERDEPENDENCECRIMINOLOGY, Issue 4 2006Article first published online: 11 DEC 200, ELAINE EGGLESTON DOHERTY Theoretical debates and empirical tests on the explanation of stability and change in offending over time have been ongoing for over a decade pitting Gottfredson and Hirschi's (1990) criminal propensity model against Sampson and Laub's (1993) life-course model of informal social control. In 2001, Wright and his colleagues found evidence of a moderating relationship between criminal propensity, operationalized as self-control, and prosocial ties on crime, a relationship they term life-course interdependence. The current study extends their research by focusing on this moderating relationship and the developmental process of desistance from crime among serious juvenile delinquents. Contrary to the life-course interdependence hypothesis, the results indicate that whereas self-control and social bonds are strongly related to desistance from crime, there is no evidence of a moderating relationship between these two factors on desistance among this sample. The implications of this research for life-course theories of crime, future research, and policies regarding desistance are discussed. [source] Hypotonic buffer induces meiosis and formation of anucleate cytoplasmic islands in the egg of the two-spotted cricket Gryllus bimaculatusDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2003Isao Sarashina In insects, egg activation is known to occur in vivo and independently of fertilization, but its mechanisms are poorly understood. To gain understanding of these mechanisms, an attempt was made to activate the egg of Gryllus bimaculatus in vitro. It was found that meiosis resumed and was completed in unfertilized eggs treated with hypotonic buffer. Early developmental processes in activated, unfertilized eggs were investigated and compared with those in fertilized eggs. Mitosis did not progress, resulting in formation of anucleate cytoplasmic islands (pseudoenergids). Development in the activated, unfertilized eggs stopped at this stage and both yolk subdivision and cellularization did not occur. To elucidate the role of the nucleus in the developmental process to the syncytial stage in fertilized eggs, eggs were treated with aphidicolin to inhibit DNA polymerization. It was found that pseudoenergids also formed in these aphidicolin-treated fertilized eggs. These results demonstrate that pseudoenergids can increase in number independently of nuclei, suggesting that the cytoplasm rather than the nucleus plays the primary role in development to the syncytial stage in G. bimaculatus. [source] Pleiotropic function of FGF-4: Its role in development and stem cellsDEVELOPMENTAL DYNAMICS, Issue 2 2009Nobuyoshi Kosaka Abstract Fibroblast growth factors (FGFs) were initially recognized as fibroblast-specific growth factor, and it is now apparent that these growth factors regulate multiple biological functions. The diversity of FGFs function is paralleled by the emerging diversity of interactions between FGF ligands and their receptors. FGF-4 is a member of the FGF superfamily and is a mitogen exhibiting strong action on numerous different cell types. It plays a role in various stages of development and morphogenesis, as well as in a variety of biological processes. Recent studies reveal the molecular mechanisms of FGF-4 gene regulation in mammalian cells, which is involved in the developmental process. Furthermore, FGF-4 also acts on the regulation of proliferation and differentiation in embryonic stem cells and tissue stem cells. In this review, we focus on the diverse biological functions of FGF-4 in the developmental process and also discuss its putative roles in stem cell biology. Developmental Dynamics 238:265,276, 2009. © 2008 Wiley-Liss, Inc. [source] Fluid dynamics of nodal flow and left,right patterning in developmentDEVELOPMENTAL DYNAMICS, Issue 12 2008Julyan H.E. Cartwright Abstract The manner in which the nodal flow determines the breaking of left,right symmetry during development is a beautiful example of the application of fluid dynamics to developmental biology. Detailed understanding of this crucial developmental process has greatly advanced by the transfer of ideas between these two disciplines. In this article, we review our and others' work on applying fluid dynamics and dynamical systems to the problem of left,right symmetry breaking in vertebrates. Developmental Dynamics 237:3477,3490, 2008. © 2008 Wiley-Liss, Inc. [source] Mice with mutations in Mahogunin ring finger-1 (Mgrn1) exhibit abnormal patterning of the left,right axisDEVELOPMENTAL DYNAMICS, Issue 12 2006Christina D. Cota Abstract Mahogunin Ring Finger 1 (Mgrn1) encodes a RING-containing protein with ubiquitin ligase activity that has been implicated in pigment-type switching. In addition to having dark fur, mice lacking MGRN1 develop adult-onset spongy degeneration of the central nervous system and have reduced embryonic viability. Observation of complete situs inversus in a small proportion of adult Mgrn1 mutant mice suggested that embryonic lethality resulted from congenital heart defects due to defective establishment and/or maintenance of the left,right (LR) axis. Here we report that Mgrn1 is expressed in a pattern consistent with a role in LR patterning during early development and that many Mgrn1 mutant embryos show abnormal expression of asymmetrically expressed genes involved in LR patterning. A range of complex heart defects was observed in 20,25% of mid-to-late gestation Mgrn1 mutant embryos and another 20% were dead. This finding was consistent with 46,60% mortality of mutants by weaning age. Our results indicate that Mgrn1 acts early in the LR signaling cascade and is likely to provide new insight into this developmental process as Nodal expression was uncoupled from expression of other Nodal-responsive genes in Mgrn1 mutant embryos. Our work identifies a novel role for MGRN1 in embryonic patterning and suggests that the ubiquitination of MGRN1 target genes is essential for the proper establishment and/or maintenance of the LR axis. Developmental Dynamics 235:3438,3447, 2006. © 2006 Wiley-Liss, Inc. [source] The intersensory origins of word-comprehension: an ecological,dynamic systems viewDEVELOPMENTAL SCIENCE, Issue 1 2001Lakshmi J. Gogate How do infants begin to understand spoken words? Recent research suggests that word comprehension develops from the early detection of intersensory relations between conventionally paired auditory speech patterns (words) and visible objects or actions. More importantly, in keeping with dynamic systems principles, the findings suggest that word comprehension develops from a dynamic and complementary relationship between the organism (the infant) and the environment (language addressed to the infant). In addition, parallel findings from speech and non-speech studies of intersensory perception provide evidence for domain general processes in the development of word comprehension. These research findings contrast with the view that a lexical acquisition device with specific lexical principles and innate constraints is required for early word comprehension. Furthermore, they suggest that learning of word,object relations is not merely an associative process. The data support an alternative view of the developmental process that emphasizes the dynamic and reciprocal interactions between general intersensory perception, selective attention and learning in infants, and the specific characteristics of maternal communication. [source] Clinician attitudes towards early psychosis intervention: the first 4 yearsACTA PSYCHIATRICA SCANDINAVICA, Issue 2002J. Gorrell Objectives, A questionnaire was administered with an aim to assess the attitudes of mental health clinicians towards the adoption of an early intervention approach and to monitor attitudinal change during the introduction of this approach. Method, The perceptions of Early Psychosis Intervention (PEPI) questionnaire was developed and then completed by clinicians at three time points over 4 years during the introduction of a best practice early intervention approach (n=143, 178, 102, respectively). Results, Indicate that at all three time points clinicians generally agreed with the potential advantages of early intervention but were unsure about their own readiness to implement such intervention. Responses to an open-ended question regarding concerns about the new approach indicated a positive shift up the developmental process of change, from initial concerns about personal skills, resources and workload, to a gradually more specific focus on particular aspects of clinical interventions and on the impact of the new approach. Conclusions, Our services have introduced early psychosis intervention. Clinicians have moved up the developmental process of change. The questionnaire has provided a means for clinicians to influence the change process. [source] Ontogeny of sexual dimorphism via tissue duplication in an ostracod (Crustacea)EVOLUTION AND DEVELOPMENT, Issue 2 2009Ajna S. Rivera SUMMARY The adaptive significance of specific sexual dimorphism is well studied. However, the evolutionary history and ontogenic origins of the dimorphism are often unknown. As dimorphism represents two phenotypes generated from relatively similar genotypes, it is of interest to understand both its evolutionary and developmental/genetic underpinnings. Here, we present the first ontogenetic examination of the eyes of philomedid ostracods (Crustacea), which exhibit extremely sexually dimorphic lateral eyes. Adult male philomedids have large compound lateral eyes, whereas females have rudimentary lateral eyes. First, we show that eye dimorphism is unlikely to be due to additional genes present on a male-specific chromosome because karyotype analysis suggests philomedids are XX/XO. We then examine the ontogeny of eye development and find that in at least two species of Euphilomedes, this dimorphism is not generated solely by differences in tissue growth rates, as has been commonly shown for sexually dimorphic characters of other species. Instead, the dimorphism appears to arise during development via tissue duplication, where a single tissue becomes two, perhaps with different developmental potentials. The second eye field is only observed in male Euphilomedes, producing most of the adult eye tissue. We point out that tissue duplication is a developmental process with evolutionary implications because novel characters could evolve via alternative modification of the duplicated fields, analogous to the origin of new genes by gene duplication and alternative modification. Depending on the evolutionary history of the duplicated field, it may have either facilitated or directly caused the observed sexual dimorphism of philomedid ostracods. [source] Measuring Hospital Care from the Patients' Perspective: An Overview of the CAHPS® Hospital Survey Development ProcessHEALTH SERVICES RESEARCH, Issue 6p2 2005Elizabeth Goldstein Objective. To describe the developmental process for the CAHPS® Hospital Survey. Study Design. A pilot was conducted in three states with 19,720 hospital discharges. Methods of Analysis. A rigorous, multi-step process was used to develop the CAHPS Hospital Survey. It included a public call for measures, multiple Federal Register notices soliciting public input, a review of the relevant literature, meetings with hospitals, consumers and survey vendors, cognitive interviews with consumer, a large-scale pilot test in three states and consumer testing and numerous small-scale field tests. Findings. The current version of the CAHPS Hospital Survey has survey items in seven domains, two overall ratings of the hospital and five items used for adjusting for the mix of patients across hospitals and for analytical purposes. Conclusions. The CAHPS Hospital Survey is a core set of questions that can be administered as a stand-alone questionnaire or combined with a broader set of hospital specific items. [source] Germ-line transformation and RNAi of the ladybird beetle, Harmonia axyridisINSECT MOLECULAR BIOLOGY, Issue 4 2006H. Kuwayama Abstract To elucidate the molecular mechanisms underlying the tremendous diversity of insect wing colour patterns, it is imperative to identify and functionally characterize the genes involved in this developmental process. Here we report the first successful germ-line transformation using the transposable element vector piggyBac in the ladybird beetle Harmonia axyridis, which demonstrates typical genetic polymorphism in its wing colour patterns. The transformation efficiency by piggyBac was 3.7% per fertile G0. We investigated the effectiveness of RNAi in Harmonia by injecting EGFP (enhanced green fluorescent protein) dsRNA into early transgenic EGFP-expressing embryos and observed substantial reduction of EGFP fluorescence in 87.2% of hatched larvae. Application of these new genetic tools to non-model insects such as Harmonia will facilitate the broad understanding of developmental mechanisms and evolutionary processes that are inaccessible using established model systems. [source] Social Policymaking and Its Institutional Basis: Transition of The Chinese Social Security SystemINTERNATIONAL SOCIAL SECURITY REVIEW, Issue 2 2006Ka Lin This article discusses Chinese social policy development in response to the growth of the market economy. It provides a general overview of the system's evolution in three stages: (1) the pre-reform period when a system of enterprise welfare was in operation; (2) a period of system transition; (3) the stage when state welfare began to take shape. These developmental trends are interpreted on the basis of three types of institutional relations: the State-enterprise relation, the enterprise- (or employer-) employee relation, and the individual/worker-State relation. Moreover, the discussion deals with policy perceptions at each stage of the developmental process. Based on these analyses, it illustrates the transformation of the Chinese social security system in a broad socioeconomic and political context, where China struggled to establish a modern, market-based enterprise system. The paper thus expounds issues of socialism, market forces and the power of organized labour. [source] Established ways to keep donor's interest aliveISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n1 2010J. Ringwald Background, The future demographic changes will be associated with an enhancement of the worldwide shortage of blood. The ageing of the population in developed countries is associated with a decrease in young individuals being potentially eligible to donate blood and an increase in older individuals who might be in the need of blood transfusion. Therefore, the retention of active blood donors (BD) is becoming more important. A substantial increase in blood donations could be achieved by a relatively small increase in BD return. It is the task of blood donation services (BDSs) to elaborate specific and adequate measures to increase the BD's likelihood to return. Successful BD retention programmes are viable to ensure a sufficient supply with blood and blood components at present and the upcoming years. Aims, To give recommendations for BD retention strategies based on a survey of potential and established measures how BD's interest could be kept alive. Methods, With focus on the last decade, literature about internal and external influences on BD's intention to regular blood donation and their actual return behaviour was reviewed. Furthermore, a special aspect was drawn on published articles about established or potential measures to increase BD's return-rate. Based on this information, different ways how BD's interest could be kept alive were suggested. Results, Overall, individuals of younger age (< 30,40 years), women, those with a lower education level are less likely to return to blood donation. External influences of friends, family or co-workers are import for starting a BD career. To become a committed BD, however, a high level of intrinsic motivation is needed. To keep BD's interest alive for a long time, BDSs should focus on the following to increase the satisfaction of the BD: Make blood donation a good experience and as convenient as possible, reduce adverse events and anxiety, and train and motivate your staff. This could be further supported by an intensive and active communication with the BDs right from the start, the application of loyalty builders to establish BD identity, and the appropriate use of incentives. Finally, temporarily deferred BDs should ask to return personally and advertisement programmes for repeat BDs should appeal on personal motivation and moral norms. However, BDS should always try to adapt their measures on their target population considering that people are different all around the world. Moreover, some promotion programmes should be even tailored for distinct subgroups of BDs to have a successful outcome. Conclusions, There is quite a number of ways to keep BDs interest alive and to start a career as a regular and committed BD. In this context, the self-identification as a BD is definitely of major importance. BDSs are challenged to support this developmental process. They have to make sure that blood donation is associated with a good experience for the BD, making him or her feeling good and happy. [source] Burnout as a developmental process among Japanese nurses: Investigation of Leiter's modelJAPAN JOURNAL OF NURSING SCIENCE, Issue 1 2005Kazuyo KITAOKA-HIGASHIGUCHI Abstract Aim:, The first object of the present study was to compare Leiter and Maslach's original model (1988) and the revised model (proposed by Leiter in 1991). The second object was to ascertain whether the process model of burnout proposed by Leiter in 1993 is applicable to Japanese nurses. Workload demand, role conflict, and interpersonal conflict were selected as organizational demands, and supervisor support, coworker support, and occupational decision authority as resources. Methods:, The subjects were Japanese clinical nurses (n = 238) working at a municipal general hospital. One hundred and eighty-three effective data was obtained. The hypotheses were tested using structural equation analysis. Results:, The results supported the revised model which maintained the sequential link from exhaustion to cynicism, but recast the relationship of professional efficacy with another two components of burnout. The hypothesized model was revised based on findings and re-analysed. The organizational demands exhibited a significant positive correlation to exhaustion. Cynicism exhibited a negative correlation to supervisor support. The job decision authority exhibited a positive correlation to professional efficacy. However, the hypothesis that supervisor support exhibits a positive correlation to professional efficacy was not supported. Conclusions:, Leiter's process model of burnout is conceptualized based on the conservation of resources (COR) theory. The results of the present study were reasonably in line with the COR theory. It was suggested that Leiter's model should be applicable to Japanese nurses. [source] Facial surface analysis by 3D laser scanning and geometric morphometrics in relation to sexual dimorphism in cerebral,craniofacial morphogenesis and cognitive functionJOURNAL OF ANATOMY, Issue 3 2005Robin J. Hennessy Abstract Over early fetal life the anterior brain, neuroepithelium, neural crest and facial ectoderm constitute a unitary, three-dimensional (3D) developmental process. This intimate embryological relationship between the face and brain means that facial dysmorphogenesis can serve as an accessible and informative index of brain dysmorphogenesis in neurological and psychiatric disorders of early developmental origin. There are three principal challenges in seeking to increase understanding of disorders of early brain dysmorphogenesis through craniofacial dysmorphogenesis: (i) the first, technical, challenge has been to digitize the facial surface in its inherent three-dimensionality; (ii) the second, analytical, challenge has been to develop methodologies for extracting biologically meaningful shape covariance from digitized samples, making statistical comparisons between groups and visualizing in 3D the resultant statistical models on a ,whole face' basis; (iii) the third, biological, challenge is to demonstrate a relationship between facial morphogenesis and brain morphogenesis not only in anatomical,embryological terms but also at the level of brain function. Here we consider each of these challenges in turn and then illustrate the issues by way of our own findings. These use human sexual dimorphism as an exemplar for 3D laser surface scanning of facial shape, analysis using geometric morphometrics and exploration of cognitive correlates of variation in shape of the ,whole face', in the context of studies relating to the early developmental origins of schizophrenia. [source] Bone Regeneration Is Regulated by Wnt Signaling,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2007Jae-Beom Kim Abstract Tissue regeneration is increasingly viewed as reactivation of a developmental process that, when misappropriated, can lead to malignant growth. Therefore, understanding the molecular and cellular pathways that govern tissue regeneration provides a glimpse into normal development as well as insights into pathological conditions such as cancer. Herein, we studied the role of Wnt signaling in skeletal tissue regeneration. Introduction: Some adult tissues have the ability to regenerate, and among these, bone is one of the most remarkable. Bone exhibits a persistent, lifelong capacity to reform after injury, and continual bone regeneration is a prerequisite to maintaining bone mass and density. Even slight perturbations in bone regeneration can have profound consequences, as exemplified by conditions such as osteoporosis and delayed skeletal repair. Here, our goal was to determine the role of Wnts in adult bone regeneration. Materials and Methods: Using TOPgal reporter mice, we found that damage to the skeleton instigated Wnt reporter activity, specifically at the site of injury. We used a skeletal injury model to show that Wnt inhibition, achieved through adenoviral expression of Dkk1 in the adult skeleton, prevented the differentiation of osteoprogenitor cells. Results: As a result, injury-induced bone regeneration was reduced by 84% compared with controls. Constitutive activation of the Wnt pathway resulting from a mutation in the Lrp5 Wnt co-receptor results in high bone mass, but our experiments showed that this same point mutation caused a delay in bone regeneration. In these transgenic mice, osteoprogenitor cells in the injury site were maintained in a proliferative state and differentiation into osteoblasts was delayed. Conclusions: When considered together, these data provide a framework for understanding the roles of Wnt signaling in adult bone regeneration and suggest a feasible approach to treating clinical conditions where enhanced bone formation is desired. [source] Embryonic undifferentiated cells show scattering activity on a surface coated with immobilized E-cadherinJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2008Masato Nagaoka Abstract Rearrangement of cell,cell adhesion is a critical event in embryonic development and tissue formation. We investigated the regulatory function of E-cadherin, a key adhesion protein, in the developmental process by using E-cadherin/IgG Fc fusion protein as an adhesion matrix in cell culture. F9 embryonal carcinoma cells usually form colonies when cultured on gelatin or fibronectin matrices. However, F9 cells cultured on the E-cadherin/IgG Fc fusion protein matrix formed a scattered distribution, with a different cytoskeletal organization and E-cadherin-rich protrusions that were regulated by Rac1 activity. The same scattering activity was observed in P19 embryonal carcinoma cells. In contrast, three types of differentiated cells, NMuMG mammary gland cells, MDCK kidney epithelial cells, and mouse primary isolated hepatocytes, did not show the scattering activity observed in F9 and P19 cells. These results suggest that migratory behavior on an E-cadherin-immobilized surface is only observed in embryonic cells, and that the regulatory mechanisms underlying E-cadherin-mediated cell adhesion vary with the state of differentiation. J. Cell. Biochem. 103: 296,310, 2008. © 2007 Wiley-Liss, Inc. [source] Activation of epidermal growth factor receptors in astrocytes: From development to neural injuryJOURNAL OF NEUROSCIENCE RESEARCH, Issue 16 2007Bin Liu Abstract The epidermal growth factor receptor (EGFR) pathway controls the phenotypic characteristics of astrocytes. In the developing central nervous system (CNS), activation of the EGFR pathway induces astrocyte differentiation, forming the cribriform structure that surrounds axons and providing a supportive environment for neurons. In the adult CNS, the EGFR pathway is absent from astrocytes but is highly up-regulated and activated following neuronal injury. Activation of the EGFR pathway triggers quiescent astrocytes to become reactive astrocytes. Although astrocytes regulated by the EGFR pathway play constructive roles in the developing CNS, astrocytes that become reactive in response to activation of the EGFR pathway appear to be destructive to neurons in the adult CNS. The reappearance and activation of EGFRs in astrocytes under pathological conditions may activate a developmental process in an adult tissue. Regulation of EGFR function in astrocytes may be a new therapeutic strategy for the treatment of neural disorders. © 2007 Wiley-Liss, Inc. [source] Expression Profile During the Development of Appressoria Induced by Hydrophobic Surfaces in Magnaporthe grisea Y34JOURNAL OF PHYTOPATHOLOGY, Issue 3 2010Qingchao Jin Abstract To study the gene expression profile during appressorium developmental process of Magnaphorthe grisea strain Y34 isolated from the rich area of Asia cultivated rice resources, expressed sequence tags (ESTs) and cDNA array analysis were performed. A total of 4756 tentative unique transcripts (TUTs) were obtained from 13 057 ESTs of the 3, ends of the strain, which was approximately 25% of the total M. grisea EST sequences deposited in the GenBank database. Approximately 84% of these TUTs matched with the published draft genome sequences of strain 70-15. Southern analyses with 12 TUT probes revealed no obvious DNA polymorphism among strains 70-15, Guy11 and Y34. A cDNA array with 4108 TUTs was used to monitor gene expression patterns during appressorium development of M. grisea. Compared with ungerminated conidia, the number of up-regulated and down-regulated genes was almost consistent at any time-points of 2, 8, 20 and 30 h during appressorium development. More genes were differentially expressed during appressorium maturation (20 and 30 h) than during appressorium induction (2 h) and formation (8 h). During appressorium maturation (20,30 h), genes generally seemed to be most actively expressed. [source] The Bps polysaccharide of Bordetella pertussis promotes colonization and biofilm formation in the nose by functioning as an adhesinMOLECULAR MICROBIOLOGY, Issue 6 2010Matt S. Conover Summary Many respiratory pathogens establish persistent infection or a carrier state in the human nasopharynx without overt disease symptoms but the presence of these in the lungs usually results in disease. Although the anatomy and microenvironments between nasopharynx and lungs are different, a virulence factor with an organ-specific function in the colonization of the nasopharynx is unknown. In contrast to the severity of pertussis and mortality in non-vaccinated young children, Bordetella pertussis results in milder and prolonged cough in vaccinated adolescents and adults. Individuals harbouring bacteria in the nasopharynx serve as reservoirs for intrafamilial and nosocomial transmission. We show that the Bps polysaccharide of B. pertussis is critical for initial colonization of the mouse nose and the trachea but not of the lungs. Our data reveal a biofilm lifestyle for B. pertussis in the nose and the requirement of Bps in this developmental process. Bps functions as an adhesin by promoting adherence of B. pertussis and Escherichia coli to human nasal but not to human lung epithelia. Patient serum specifically recognized Bps suggesting its expression during natural human infections. We describe the first bacterial factor that exhibits a differential role in colonization and adherence between the nasopharynx and the lungs. [source] The cell differentiation protein SpoIIE contains a regulatory site that controls its phosphatase activity in response to asymmetric septationMOLECULAR MICROBIOLOGY, Issue 4 2002Andrea Feucht Summary Starvation induces Bacillus subtilis to initiate a simple, two-cell developmental process that begins with an asymmetric cell division. Activation of the first compartment-specific transcription factor, ,F, is coupled to this morphological event. SpoIIE, a bifunctional protein, is essential for the compartment-specific activation of ,F and also has a morphogenic activity required for asymmetric cell division. SpoIIE consists of three domains: a hydrophobic N-terminal domain, which targets the protein to the membrane; a central domain, involved in oligomerization of SpoIIE and interaction with the cell division protein FtsZ; and a C-terminal domain comprising a PP2C protein phosphatase. Here, we report the isolation of mutations at the very beginning of the central domain of spoIIE, which are capable of activating ,F independently of septum formation. Purified mutant proteins showed the same phosphatase activity as the wild-type protein in vitro. The mutant proteins were fully functional in respect of their localization to sites of asymmetric septation and support of asymmetric division. The data provide strong evidence that the phosphatase domain of SpoIIE is tightly regulated in a way that makes it respond to the formation of the asymmetric septum. [source] The asgE locus is required for cell,cell signalling during Myxococcus xanthus developmentMOLECULAR MICROBIOLOGY, Issue 4 2000Anthony G. Garza In response to starvation, Myxococcus xanthus undergoes a multicellular developmental process that produces a dome-shaped fruiting body structure filled with differentiated cells called myxospores. Two insertion mutants that block the final stages of fruiting body morphogenesis and reduce sporulation efficiency were isolated and characterized. DNA sequence analysis revealed that the chromosomal insertions are located in open reading frames ORF2 and asgE, which are separated by 68 bp. The sporulation defect of cells carrying the asgE insertion can be rescued phenotypically when co-developed with wild-type cells, whereas the sporulation efficiency of cells carrying the ORF2 insertion was not improved when mixed with wild-type cells. Thus, the asgE insertion mutant appears to belong to a class of developmental mutants that are unable to produce cell,cell signals required for M. xanthus development, but they retain the ability to respond to them when they are provided by wild-type cells. Several lines of evidence indicate that asgE cells fail to produce normal levels of A-factor, a cell density signal. A-factor consists of a mixture of heat-stable amino acids and peptides, and at least two heat-labile extracellular proteases. The asgE mutant yielded about 10-fold less heat-labile A-factor and about twofold less heat-stable A-factor than wild-type cells, suggesting that the primary defect of asgE cells is in the production or release of heat-labile A-factor. [source] Chlamydospore formation in Candida albicans and Candida dubliniensis, an enigmatic developmental programmeMYCOSES, Issue 1 2007Peter Staib Summary Chlamydospore formation has served for a long time for identification of the human fungal pathogen Candida albicans, but the biological function of these structures still remains a secret. They have been proposed to allow survival in harsh environmental conditions, but this assumption remains to be proven. Chlamydospores are produced only by the two closely related species C. albicans and Candida dubliniensis, whose natural habitats are humans and warm-blooded animals, but not by other Candida species that are also found outside animal hosts. However, no role in the pathogenesis of Candida infections has been assigned to these unusual cells and only a limited number of studies have been conducted in the past to unravel their function. The development of new molecular tools and the recent discovery of mating in C. albicans have also restimulated investigations to understand the morphogenesis and function of chlamydospores. The finding that chlamydospore formation is differentially controlled by certain environmental signals in C. albicans and C. dubliniensis has opened new approaches to study the regulation of this morphogenetic programme. These studies have already identified genes and signalling pathways that are required for chlamydospore production and should lead to a detailed understanding of this fascinating developmental process. [source] Hypoplasia of the arcuate nucleus and maternal smoking during pregnancy in sudden unexplained perinatal and infant deathNEUROPATHOLOGY, Issue 4 2004Anna Maria Lavezzi Maternal smoking during pregnancy is the most important risk factor for sudden perinatal and infant death in more industrialized countries. The frequent observation of hypoplasia of the arcuate nucleus in the brainstem of these victims prompted the verification of whether maternal cigarette smoking could be related to defective development of this nucleus during intrauterine life, by affecting the expression of specific genes involved in its developmental process. In serial sections of the brainstem of 54 cases of sudden and unexplained fetal and infant deaths (13 stillbirths, 7 neonatal deaths and 34 sudden infant death syndrome (SIDS) victims), morphological and morphometrical analysis was used to observe the different structural alterations of the arcuate nucleus (bilateral hypoplasia, monolateral hypoplasia, partial hypoplasia, delayed neuronal maturation and decreased neuronal density) detected in 24 cases (44%). Correlating this finding with smoking in pregnancy, a significantly increased incidence of cytoarchitectural alterations of the arcuate nucleus was found in stillborns and SIDS victims with smoker mothers compared to victims with non-smoker mothers. Moreover, the observation of a wide range of developing morphological defects of the arcuate nucleus related to maternal smoking led to the hypothesis that the constituents of the gas phase in cigarette smoke could directly affect the expression of genes involved in the development of this nucleus, such as the homeobox En-2 gene. [source] Using qualitative methods to study friendshipsNEW DIRECTIONS FOR CHILD & ADOLESCENT DEVELOPMENT, Issue 107 2005William Bukowski Basic concepts and procedures of qualitative analysis are discussed, especially as they relate to the study of the features, processes, and effects of friendships. The contributions of the previous chapters are presented according to theory and research on friendship as a developmental process. [source] Activity and concentration of non-proteolyzed phosphoenolpyruvate carboxykinase in the endosperm of germinating castor oil seeds: effects of anoxia on its activityPHYSIOLOGIA PLANTARUM, Issue 4 2007Mariana Martín Phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.49) catalyses the reversible decarboxylation of oxaloacetate to phosphoenolpyruvate in the gluconeogenic production of sugars from storage lipids in germinating oil seeds. The enzyme is quite susceptible to limited proteolysis during extraction. Immunoblotting was used to diagnose unwanted in vitro proteolytic activity against PEPCK from germinating castor oil seeds (COS) by following the disappearance of its native 74-kDa subunit and concomitant appearance of a truncated 64-kDa polypeptide. Alkaline pH and the inclusion of thiol protease inhibitors effectively prevented COS PEPCK proteolysis during incubation of clarified COS extracts at 4°C. The carboxylating and decarboxylating activities and concentration of non-proteolyzed COS PEPCK were investigated during germination. This is the first report in which both activities catalyzed by PEPCK were measured in vitro during a whole developmental process. Carboxylating activity and the level of immunoreactive 74-kDa PEPCK polypeptides rapidly increased in parallel to maximal values by day 5 and then significantly declined over the subsequent 2 days. In contrast, decarboxylating PEPCK activity was much higher over the 7 days of growth examined. In addition, the effect on PEPCK activity while changing the endosperm from aerobic (when gluconeogenesis predominates in the tissue) to anaerobic conditions (where the tissue becomes glycolytic) was studied. While PEPCK decarboxylating activity remained almost constant, carboxylating activity declined to undetectable levels in response to anaerobiosis. These and the developmental profile results suggest that COS PEPCK may be subject to a mechanism of post-translation control that selectively inhibits the carboxylating, but not the decarboxylating activity. [source] Co-action of temperature and phosphate in inducing turion formation in Spirodela polyrhiza (Great duckweed),PLANT CELL & ENVIRONMENT, Issue 9 2002K.-J. Appenroth Abstract Increased phosphate concentration, higher temperature and addition of glucose all increased the number of fronds and turions of the duckweed Spirodela polyrhiza formed under in vitro conditions. Increasing the number of turions by increasing the plant biomass does not mean that the developmental process (switch of the programme of the primordia from vegetative fronds toward resting turions) has been specifically influenced. The specific turion yield (STY; number of turions formed by one frond) and the time of onset of turion formation have been used as more specific measures of turion induction. At more than 30 µm initial phosphate the STY was increased by lower temperature (15 °C) and became independent of the phosphate concentration. Between 10 and 30 µm and at higher temperatures (25 °C) the STY was increased by lower phosphate levels. The stimulatory effect of lower temperature was more pronounced than that of lower phosphate concentrations. Decreased phosphate concentration highly accelerated the formation of the first turions. The influence of low temperature was small at lower phosphate concentration but became dominant at higher concentrations (especially in autotrophic cultures). Low phosphate levels (e.g. 10 µm) and low temperatures (e.g. 15 °C) both represent specific turion-inducing factors having significant interactive effects. In S. polyrhiza, these signals may replace the interactive effects of photoperiods and low temperature known from other hydrophytes in turion induction under natural conditions. [source] Proteomic and transcriptomic analysis of rice mature seed-derived callus differentiationPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2007Lan Yin Abstract Callus differentiation is a key developmental process for rice regeneration from cells. To better understand this complex developmental process, we used a 2-D gel electrophoresis approach to explore the temporal patterns of protein expression at the early stages during rice callus differentiation. This global analysis detected 60 known proteins out of 79 gel spots identified by MS/MS, of which many had been shown to play a role in plant development. Two new proteins were revealed to be associated with the callus differentiation and have been confirmed by Western blot analysis. The results of proteomics experiments were further verified at the mRNA level using microarray and real-time PCR. Comparison of the differentially expressed protein levels with their corresponding mRNA levels at the two callus early differentiation stages showed a good correlation between them, indicating that a substantial proportion of protein changes is a consequence of changed mRNA levels, rather than post-transcriptional effects during callus differentiation, though microarray revealed more expression changes on RNA levels. These findings may contribute to further understanding of the mechanisms that lead to callus differentiation of rice and other plants as well. [source] Parish Nursing: Nurturing Body, Mind, Spirit, and CommunityPUBLIC HEALTH NURSING, Issue 2 2003Ingrid Brudenell R.N., Ph.D. Abstract Parish nursing is a model of nursing care that focuses on health promotion and disease prevention within a faith community. A descriptive study was conducted in the intermountain West to determine how faith communities form parish nursing programs and what their effect is. Thirteen congregations representing eight denominations with parish nurse/health ministries participated. Parish nurses, parish nurse coordinators from two medical centers, pastors, and hospital chaplains (n = 24) were interviewed and provided documents from their programs. Over time, congregations formed parish nursing/health ministries using strategies in a developmental process. The process involved significant support from the pastor, congregation members, and the parish nurses. Collaboration between faith communities and health organizations were successful using a limited domain approach to attain specific health goals. Parish nursing is making a contribution to integrating faith and health practices, promoting health, and increasing accessibility to health care and congregational activities. Conclusions and recommendations are included for future research, practice, and education. [source] A Study of the Temporal Course of Phenomenology of Alcohol DependenceTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 3 2005Satindra Kumar M.B.B.S. The natural history of alcoholism was first charted out in 1946 by Jellinek, whose original results have been replicated by multiple research groups. They have verified a general progression ofalcohol dependence through a series of identifiable phases. The study investigated the sequence of events in the course of alcohol dependence and its deviations from randomness. The study consisted of 36 patients with alcohol dependence, subjected to a structured questionnaire containing 34 items describing the phenomenology of alcohol dependence, based on the lines of SCID. The items experienced by each patient were identified and then plotted on a timeline graph according to an important life event, the items being represented on cards given to the patients randomly. The subjects were reinterviewed after one week and asked to rank their symptoms again to analyze test-retest reliability. The analysis ofthe item ordering was determined by null hypothesis of randomness. The ordering showed three phases. The early phase was characterized by features of increased tolerance loss of flexibility, and salience. The middle phase consisted mainly of the need for alcohol, and the late phase was predominated by features of physiological withdrawal, tremors, nausea, panics, and hallucinations. There is a characteristic ordering of new events and symptoms, which suggests a developmental process of alcoholism, but this is apparent only if attention is confined to a limited part ofthe broad spectrum. This process is obscured by consideration ofthe social concomitants of alcohol dependence. The study ofthe natural history of alcohol dependence is essential in recognizing and treating the problem and determining whether an intervention appears to be working. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||