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Expression and function of the empty spiracles gene in olfactory sense organ development of Drosophila melanogaster

Expression and function of the empty spiracles gene in olfactory sense organ development of Drosophila melanogaster

In Drosophila, the cephalic gap gene empty spiracles plays key roles in embryonic patterning of the peripheral and central nervous system. During postembryonic development, it is involved in the development of central olfactory circuitry in the antennal lobe of the adult. However, its possible role in the postembryonic development of peripheral olfactory sense organs has not been investigated. Here, we show that empty spiracles acts in a subset of precursors that generate the olfactory sense organs of the adult antenna. All empty spiracles-expressing precursor cells co-express the proneural gene amos and the early patterning gene lozenge. Moreover, the expression of empty spiracles in these precursor cells is dependent on both amos and lozenge. Functional analysis reveals two distinct roles of empty spiracles in the development of olfactory sense organs. Genetic interaction studies in a lozenge-sensitized background uncover a requirement of empty spiracles in the formation of trichoid and basiconic olfactory sensilla. MARCM-based clonal mutant analysis reveals an additional role during axonal targeting of olfactory sensory neurons to glomeruli within the antennal lobe. Our findings on empty spiracles action in olfactory sense organ development complement previous studies that demonstrate its requirement in olfactory interneurons and, taken together with studies on the murine homologs of empty spiracles, suggest that conserved molecular genetic programs might be responsible for the formation of both peripheral and central olfactory circuitry in insects and mammals.

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Mechanical control of tissue and organ development

Mechanical control of tissue and organ development

The asymmetric distribution of cytoskeletal and junctional proteins also contributes to polarized cell behavior during hexagonal packing (Blankenship et al., 2006), and actomyosin- dependent contractility as well as long-distance force transmission across the tissue appear to be crucial for this process. For example, myosin II is enriched in a bipolar manner within the aligned cells of the prospective denticle field and contributes to cell rearrangements during the establishment of PCP in the forming wing by acting in concert with denticle field-specific effectors (Walters et al., 2006). Thus, these epithelial packing patterns, which govern functional wing formation, also appear to be determined by a balance between cytoskeletal pulling forces and resisting adhesive tethers that attach to neighboring cells and the underlying ECM (Farhadifar et al., 2007). Interestingly, studies on adult mammalian cells indicate that endothelial cells similarly polarize their cytoskeleton, nucleus and membrane components when they pull against an adhesive substrate (Ingber et al., 1986), and that they also use mechanical feedback and Rho signaling to sense these cell shape asymmetries (Mammoto et al., 2007). The modulation of cytoskeletal tension through the Rho/ROCK/myosin II pathway regulates Wnt/PCP signaling, which controls junctional resistance sites (Figs 2, 3) crucial to the establishment of cell orientation. This, in turn, is pivotal for the control of cell division (Karner et al., 2009), directional cell migration (Phillips et al., 2005; Bastock and Strutt, 2007) and packing geometry (Chen et al., 2006). In mouse kidney development, a similar mechanochemical PCP signaling mechanism underpins the consistent orientation of mitotic cells along the tubular axis that drives the lengthening of developing renal tubules. A disturbance of mechanosensing by the primary D E

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Endoreduplication mediated initiation of symbiotic organ development in Lotus japonicus

Endoreduplication mediated initiation of symbiotic organ development in Lotus japonicus

Fig. 4. The effect of the vag1 mutation on early nodule development. (A-E) Initiation of nodule organogenesis in DR5:: GFP-NLS/WT (A-C) and DR5::GFP-NLS/vag1-1 (D,E) transgenic plants. Roots were observed at 3 (A-E, except C) and 5 (C) dai with rhizobia that constitutively express DsRED. Auxin response patterns during nodulation were visualized by GFP fluorescence (green). Nuclei were stained with DAPI (blue). Arrowheads indicate enlarged nuclei. For fluorescence analysis, at least 20 plants were analyzed at each developmental stage in three independent experiments. (F) X-Gluc staining of a root region containing dividing cortical cells in wild-type transgenic hairy roots containing the pLjCCS52A1-LIKE2::GUS construct at 5 dai. (G-I) In situ localization of LjCCS52A1-LIKE1 transcripts in wild-type root regions containing dividing cortical cells at 3 dai (G,I) and 5 dai (H). Antisense (G,H) or sense (I) probes were used for the detection of LjCCS52A1-LIKE1 transcripts. Scale bars: 100 μ m.

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Pathogenesis of bronchopulmonary dysplasia: when inflammation meets organ development

Pathogenesis of bronchopulmonary dysplasia: when inflammation meets organ development

Imbalance of pro-inflammatory cytokines and growth factors Since the early 1990s, it is well known that the pulmon- ary inflammatory response due to mechanical ventilation and oxygen therapy is characterized by a disbalance of pro-inflammatory cytokines and growth factors followed by the influx of inflammatory cells into the lung. Since the first observations of cytologic changes in the tracheal aspirates of preterms developing BPD, a plenty of studies has detected an association between higher levels of typical pro-inflammatory cytokines like IL-1β, IL-6, IL-8, TNF-α, monocyte chemo-attractant proteins, and macrophage inflammatory proteins in the tracheal aspir- ate of the mechanically ventilated preterm infant and the later development of BPD [26, 27]. The initiation of the inflammatory response can already occur in utero, i.e., in the situation of chorioamnionitis [28]. Further evaluation of these markers of inflammation in the tracheal aspirate and peripheral blood of the preterm infant is necessary to confirm the applicability as early biomarkers of dis- ease severity [29, 30]. The rise in pro-inflammatory cyto- kines is accompanied by the upregulation of cell adhesion molecules like ICAM-1 and L-selectin and by the increase in chemotactic proteins that attract the in- flammatory cells into the lung. The pulmonary attraction of these cells leads to the persistence of the inflamma- tory response and the accumulation of NF-kB within this cellular fraction. In parallel, the levels of classical anti- inflammatory cytokines like IL-10 and of central growth

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Bidder’s organ – structure, development and function

Bidder’s organ – structure, development and function

Our studies showed that in Bufo viridis and Bufo bufo the ante- rior region of genital ridge grows more rapidly than the rest of the developing gonads due to the increase of germ cell number at the early stage of gonadogenesis (Gonser stage 29). This prolifera- tion of germ cells in the future Bidder’s organ leads to the club-like shape appearance of the developing gonads. Because in bufonids the development of Bidder’s organ correlates with the appearance of the oocytes in the anterior tip of developing gonad, we hypoth- esized that the meiotic entry is the major determinant of Bidder’s organ development (Piprek et al., 2013). Previously it was shown that retinoic acid (carotenoid compound) induces meiosis in mouse (Bowles et al., 2006; Koubova et al., 2006). We showed previously that inhibition of retinoic acid synthesis by citral as well as blockage of retinoic acid receptors by BMS453 (4-[(1E)-2-(5,6-dihydro-5,5- dimethyl-8-phenyl-2-naphthalenyl)ethenyl]-benzoic acid) results in decrease or lack of diplotene oocytes in in vitro developing larval Bidder’s organs (Table 1; Piprek et al., 2013). This study indicated that the retinoic acid induces meiosis both in Bidder’s organ and in developing ovaries. We also showed that there is a higher level of Raldh2 (retinoic acid synthesizing enzyme) in somatic cells of the developing Bidder’s organ than in developing ovaries and testes. In contrast, the level of Cyp26b1 (retinoic acid-degrading enzyme) is lower in the developing Bidder’s organ at Gosner stage 33 (the time of bidderian oocytes appearance and toe differentiation stage) than in the rest of the gonad (Piprek et al., 2013). This suggests that

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Sexual Dimorphism in White Campion: Deletion on the Y Chromosome Results in a Floral Asexual Phenotype

Sexual Dimorphism in White Campion: Deletion on the Y Chromosome Results in a Floral Asexual Phenotype

Figure 2.—Defined stages of reproductive organ development in flower buds of wild-type female and asexual mutants asx2 and asx1. The staging of flower bud development is according to Farbos et al. (1997). (A–C) Wild- type female flower. (A) Flower bud at female stage 7.2 showing three stamens undergoing the first step(s) of differentiation: an- thers at bilobal stage with short filaments. (B) Stage 8 with en- larged ovary and stamens reach- ing terminal development (also see Figure 3B). (C) Detail of vesti- gial anthers of the flower at stage 12 (in bloom). (D–H) Flower de- velopment in the mutant asx2. (D) Flower bud at corresponding male stage 7 with two subwhorls of stamens. The outer whorl sta- mens have bilobal anthers. (E) Stage 9 exhibiting petals, the cen- tral “finger-like projection,” and stamens at terminal differentia- tion: bilobal anthers in both inner and outer stamen circles. (F) De- tail of the abaxial side of the sta- men rudiments showing cell col- lapse at stage 11. (G) Top view of a flower bud at the same stage: the “finger-like projection” was sectioned. It contains parenchy- matous cells only. (H) Flower at stage 12 showing vestigial stamens (arrowheads). (I–M) Flower de- velopment in the mutant asx1. (I) Flower bud at male stage 9 with the inner and outer circles of sta- mens at terminal differentiation (compare with E from above). ( J) Bud with detached petals to show the beginning of stamen degener- ation (arrow) at early stage 10. (K) Top view of a flower bud at stage 12 (in bloom). Note the at- rophy of the stamens. (L) Section through a stamen at the same stage as in J, showing only paren- chymatous cells. (M) Detail of the abaxial side of degenerated sta- mens as shown in K. P, petal; St, stamen, primordium, or vestigial; Ov, ovary. Bar, 100 mm.

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Reproductive regulators in decapod crustaceans: an overview

Reproductive regulators in decapod crustaceans: an overview

Development of the crustacean male reproductive system has been studied by several investigators. The crustacean eyestalk is known to control testicular function (Figs4 and 5). For example, eyestalk removal in non-breeding adult males induces precocious spermatogenesis, and hypertrophy in the androgenic gland (Demeusy, 1953; Gomez and Nayar, 1965; Otsu, 1963). ESA of male white shrimp, L. vannamei, increased testicular size and doubled mating success (Chamberlain and Lawrence, 2009; Sreekumar and Adiyodi, 1983) suggested that ablation stimulates spermatogenesis and that inhibitory eyestalk principles (possibly GIH or MIH) play a role in the synchronized regulatory processes of reproduction and molting in Macrobrachium idella. Eyestalk removal in male Penaeus vannamei also enhanced the testicular index, spermatophore weight and total number of sperm but did not affect sperm viability (Leung-Trujillo and Lawrence, 2009). Unilaterally, ESA male P. monodon showed a significantly higher sperm count, larger sperm head diameter and longer spikes in comparison to unablated ones, but no observable changes were noted in testicular index, spermatophore weight and sperm viability (Gomes and Honculada-Primavera, 1993). We also found that the ESA of C. maenas caused testicular index to increase to 2-fold higher than that of intact green crabs (Nagaraju and Borst, 2008). These and other research studies have led to the proposal that the eyestalk contains an inhibitory factor called GIH (Fingerman, 1997a; Haihui et al., 2006; Kulkarni et al., 1984), but the structural information and molecular and cellular mechanisms remain to be elucidated.

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Next-generation calcineurin inhibitors in development for the prevention of organ rejection

Next-generation calcineurin inhibitors in development for the prevention of organ rejection

Abstract: Calcineurin inhibitors (CNIs) remain the cornerstone of immunosuppression after renal transplantation despite their adverse effects. Some CNIs have well known negative impacts on the cardiovascular system, including hypertension, hyperlipidemia, new onset diabetes after transplantation (NODAT), neurotoxicity, hypertrichosis, and nephrotoxicity. Many clinical tri- als dealing with CNI avoidance or elimination were associated with higher risk of rejection of the transplanted organ. New generation CNIs are concerned with modifying CNI molecules so that they become more potent and are suitable for patients with suboptimal adherence with less adverse effects. In this review, we address these issues.

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Understanding Organisational Development: Conceptsand Relevance

Understanding Organisational Development: Conceptsand Relevance

Organization development can be distinguished from change management and organizational change. OD and change management both address the effective implementation of planned change. They are both concerned with the sequence of activities, processes, and leadership issues that produce organization improvements. They differ, however, in their underlying value orientation. OD’s behavioral science foundation supports values of human potential, participation, and development in addition to performance and competitive advantage. Change management focuses more narrowly on values of cost, quality, and schedule. 7 As a result; OD’s distinguishing feature is its concern with the transfer of knowledge and skill so that the system is more able to manage change in the future. Change management does not necessarily require the transfer of these skills. In short, all OD involves change management, but change management may not involve OD.

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ORGAN TRANSPLANTATION: A HOPE OF SURVIVAL

ORGAN TRANSPLANTATION: A HOPE OF SURVIVAL

Organ transplantation is only the hope of the survival for the patient suffering from life threatening diseases such as heart and liver diseases. Today Organ transplant is A major area of research for the physician. Organ Transplantation provides new life to the patient but some complication like graft reject reaction are very common from the organ transplant and that can be minimized by using a close donor and suitable immunosuppressant drugs. The Availability of the organ is another problem associated with organ transplant that can be minimized using artificial organ, Animal organ, stem cell and aborted fetus. The Major Organ transplanted are Kidney, Liver, Heart, Pancreas,Cornea,Lungs etc. Newer Immunosuppressant drugs cause a dramatic change in organ transplant because they minimize the Graft-Reject reaction and Improves the quality of life. The following article covers complete description about organ transplant, types of transplant, Graft-Reject reaction and its treatment etc.

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Organ Procurement in the United States- A Historical Review of Legislative and Regulatory Breakthroughs in the Development of a New Healthcare Subsector

Organ Procurement in the United States- A Historical Review of Legislative and Regulatory Breakthroughs in the Development of a New Healthcare Subsector

approach has obvious ethical concerns and is unlikely to be ever put into effect. Presumed consent model, where all individuals are presumed to want to donate their organs unless they explicitly refuse, has shown to improve donation rates in countries like Spain [29]. Another idea that was in the news in 2013 was the use of rapid organ recovery ambulance to stabilize the deceased and quickly transport them to the hospital for medical management and organ recovery [30]. In 2013, the National Institutes of Health funded a pilot project to test if transplantable lungs could be perfused, ventilated and transported by the EMS crew [31]. After initial screening, fifteen patients were considered for donation potential, of which two patients were transferred to the hospital for organ recovery [31]. Focus has also been on using innovative approaches to preserve organs that were previously lost in difficult conditions, for example, using in-situ cold perfusion prior to organ retrieval where unexpected cardiac arrest occurred in a brain-dead patient [32]. While standalone policy proposals are not going to be sufficient, incremental effects of all efforts combined will hopefully be able to make a dent in the organ shortage. Meanwhile, prevention and early diagnosis and treatment of medical problems remains the first line of defense.

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Political Considerations of Controversial Medical Issues: Xenotransplantation and Society. A Presentation of the Work of the Norwegian National Working Group on Xenotransplantation

Political Considerations of Controversial Medical Issues: Xenotransplantation and Society. A Presentation of the Work of the Norwegian National Working Group on Xenotransplantation

A xenotransplantation working group was es- tablished in April 2000 as a consequence of this decision, and in many ways I think that the composition of this group was decisive for the final conclusion. The members of this group were chosen from a wide range of expert areas in society, such as law, human and veterinary medicine, ethics and animal welfare and risk management. The chairwoman of this working group, and the author of the current paper, owned experience from a political career at a national level, and I am currently the governor of the county of Nord-Trøndelag, Norway. In the following paper the work of this group will be presented. This paper addresses the media reactions, the political considerations and deci- sions, further development and the preliminary conclusions regarding the issue of xenotrans- plantation in the Norwegian society.

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The role of intestinal mucosa injury induced by intra abdominal hypertension in the development of abdominal compartment syndrome and multiple organ dysfunction syndrome

The role of intestinal mucosa injury induced by intra abdominal hypertension in the development of abdominal compartment syndrome and multiple organ dysfunction syndrome

the release of a cascade of cytokines and other proinflam- matory or inflammatory substances, which themselves play a vital role in the genesis and development of sys- temic inflammatory response syndrome, sepsis and organ dysfunction or failure [39-41]. These cytokines and neu- trophil migration conversely stimulate vascular endothelial cells, leading to ‘ capillary leak syndrome’. As this patho- physiologic process has some analogy with acute lung in- jury (ALI) or acute renal injury (ARI), it has been suggested that the terms acute intestinal distress syn- drome (AIDS) or acute intestinal permeability syndrome (AIPS) are used to describe the intestinal dysfunction resulting from shock or ischemia [42-44].

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Addressing Social Determinants of Health: Challenges and Opportunities in a Value-Based Model

Addressing Social Determinants of Health: Challenges and Opportunities in a Value-Based Model

OPPORTUNITY 1: ENGAGING DIVERSE SECTORS TO IMPROVE CHILD HEALTH A value-based health care system that comprehensively addresses families’ adverse social circumstances by engaging multiple sectors has the potential to improve the quality of children ’ s care, address impediments that jeopardize health, and improve wellbeing. Since 2003, the Maternal and Child Health Bureau has encouraged and supported the development of Early Childhood Comprehensive Systems as partnerships between “…agencies [and/or] organizations representing physical and mental health, social services, families and caregivers, and early-childhood education to promote seamless care for young children…” 5

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A monoclonal antibody to the adherence promoting leukocyte glycoprotein, CD18, reduces organ injury and improves survival from hemorrhagic shock and resuscitation in rabbits

A monoclonal antibody to the adherence promoting leukocyte glycoprotein, CD18, reduces organ injury and improves survival from hemorrhagic shock and resuscitation in rabbits

resuscitation, only 29% survived 5 d. All had gross and histologic evidence of injury to lungs, liver, and gastrointestinal mucosa. In contrast, 100% of the MAb 60.3-treated animals survived 5 d (P less than 0.01) and organ injury was absent or markedly attenuated. The control animals also had a persistent acidosis, lost more weight, and had evidence of continued gastrointestinal bleeding in contrast to MAb 60.3-treated animals. We conclude that increased leukocyte adhesiveness plays an important role in the development of multiple organ injury and death after generalized ischemia-reperfusion and that this injury may be significantly reduced by blocking leukocyte adherence functions with the MAb 60.3.

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Non cell autonomously coordinated organ size regulation in leaf development

Non cell autonomously coordinated organ size regulation in leaf development

We established heat shock (HS)-dependent AN3 activation and deletion systems (Fig. 1) by applying a Cre/lox-mediated recombination mechanism (Y. Ichihashi, G.H., T. Takahashi and H.T., unpublished). In these systems, expression of AN3 tagged with triple green fluorescent protein (3xGFP) was either activated (Fig. 1A) or repressed (Fig. 1B) in the an3-4 background upon HS. Neither HS treatment nor expression of 3xGFP or -glucuronidase (GUS) affected normal leaf development (see Fig. S1 in the supplementary material). We could induce HS-dependent recombination in cells of entire primordia (see Fig. S2 in the supplementary material) or in parts of leaf primordia (see below) by optimising the HS conditions. We confirmed that AN3-3xGFP had a comparable cell proliferation-promoting activity to native AN3, and that our AN3 activation and deletion systems were properly established for the analyses described below (see Figs S2 and S3 in the supplementary material).

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ESF Annual Report 2006

ESF Annual Report 2006

Biomedical research has entered the post-genomic phase following the completion of the Human Genome project and other related sequencing efforts. The functional analysis of gene products (functional genomics) gave rise to the ‘omics’ disciplines including proteomics, defi ned as the identifi cation and characterisation of proteins and their interactions as well as of protein expression. However, proteomics does not describe post-translational modifi cations of proteins that are in many instances necessary for biological activity. While recent years have witnessed an unprecedented growth of knowledge in proteomics, the time for generating broad insights into post- translational modifi cations has now arrived, especially in the fi eld of glycomics (glycoscience), lipidomics 1 , phosphorylation ‘omics’ and even Structural Medicine as such. Glycomics describes and analyzes the structure of sugar molecules in glycoconjugates. Carbohydrates present in glycoconjugates such as glycolipids and glycoproteins contribute decisively to their functionality. Certain glycosylation patterns give proteins specifi c physical, biochemical and biological characteristics and cause their structural and functional variance. Currently, some far-reaching biomedical consequences of changes in the structure and metabolism of glycans are already known: these are indicators of diseases such as congenital disorder of glycosylation, inclusion body disease, tumors, infl ammation, diabetes mellitus, intoxications (alcohol, drugs) and microbial infections. Changes in glycan structure themselves play a causative role in the development of infl ammation, arteriosclerosis, immune defects and autoimmunity, infections (e.g. infl uenza, virus hepatitis, meningitis and HIV) and the invasion of cancer cells. Expanded knowledge on disease-related changes in glycosylation patterns and its integration in genome and proteome data provides new basic biomedical insights and thus, far-reaching possibilities for diagnostic application (prevention, fi rst diagnosis, treatment follow-up, and prognostic assessment) as well as for the development of new therapeutic approaches.

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The Situation of Learning and Prospects for Improvement in a Tourism Organization

The Situation of Learning and Prospects for Improvement in a Tourism Organization

Collaboration and encouragement of learning are important factors in a learning organization. Almost all employees of a tourism organization (90.4) have stated that employees collaborate, respect each other, take care of new employees, there are conditions for experimenting, but on the other hand they are not sure about the absence of rivalries and whether a good-willing atmosphere always prevails. A tourism organization is a business entity and competition encourages continuous learning of the staff. Services in a learning tourism organization can be rendered by using educational processes where knowledge, abilities and values are regarded as the most important measures used to improve the tourism service. Therefore, it is important to know how employees view these measures. The organization pays great attention to the professional development of the staff, and that means that employees have all opportunities to learn. The results of employees’ attitude towards knowledge and evaluation of personal skills are presented. The survey results have indicated that knowledge is regarded as a value in the organization, employees show personal initiative to gain knowledge and develop, employees have good practical competencies which are important in the organization, the organization retains and educates its customers by offering new tours

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A population-based study of the stratum corneum moisture

A population-based study of the stratum corneum moisture

After 24 hours without using any type of cosmetics, weak evidence was found for extended effects of the products on the SC moisture for this sample. This implies that most mois- turizers or other products present only short-term effects on skin hydration properties. The dynamics of the layer poses difficulties for the development of protective agents for the skin. Nevertheless, sunscreen use presented a high association with the SC moisture levels as a protective factor against sun exposure, according to its frequency of use, showing lower moisture levels in individuals who used sunscreen irregularly. It is also important to note that the coefficients found in modeling present higher values of sun exposure effect than the coefficient for sunscreen use, indicating that, on average, even subjects who use sunscreen regularly present a significant influence of sun exposure on skin moisture.

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Tbx2b is required for the development of the parapineal organ

Tbx2b is required for the development of the parapineal organ

The formation of an organ requires specification of multiple cell types within a primordium, followed by appropriate morphogenetic movements that shape the mature organ. In the case of asymmetrically shaped and positioned organs, morphogenesis must also be regulated along the left-right (L-R) axis. The zebrafish presents a unique opportunity to study the formation of an asymmetric region in the brain, namely the pineal complex, which is found in the dorsal diencephalon (epithalamus). The pineal complex includes the melatonin-secreting pineal organ and the left- sided parapineal organ (Butler and Hodos, 1996; Borg et al., 1983). In adult fish, the pineal organ is attached to the brain via a stalk, which emerges just to the left of the midline (Liang et al., 2000). The parapineal organ is situated within the brain to the left of the pineal stalk (Gamse et al., 2002). Adjacent to the pineal complex are the bilateral habenular nuclei (habenulae). Along with the medial forebrain bundle, the habenulae and their efferent connections are a principal pathway connecting the limbic forebrain with the midbrain. Habenular axons travel via the fasciculi retroflexus (FR) to the interpeduncular nucleus (IPN) of the midbrain; this habenulo- interpeduncular connection is highly conserved throughout the vertebrate lineage (Sutherland, 1982). In teleosts, including zebrafish, axons from the left versus right habenula innervate different dorsoventral regions of the IPN, in contrast to other vertebrates, in which the two habenulae exhibit similar connections to the IPN (Kuan et al., 2007a).

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