Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Destination”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,027 records · Page 57Linked to original sources

A microarray analysis of gene expression in the free-living stages of the parasitic nematode Strongyloides ratti.

BACKGROUND: The nematode Strongyloides ratti has two adult phases in its lifecycle: one obligate, female and parasitic and one facultative, dioecious and free-living. The molecular control of the development of this free-living generation remains to be elucidated. RESULTS: We have constructed an S. ratti cDNA microarray and used it to interrogate changes in gene expression during the free-living phase of the S. ratti life-cycle. We have found very extensive differences in gene expression between first-stage larvae (L1) passed in faeces and infective L3s preparing to infect hosts. In L1 stages there was comparatively greater expression of genes involved in growth. We have also compared gene expression in L2 stages destined to develop directly into infective L3s with those destined to develop indirectly into free-living adults. This revealed relatively small differences in gene expression. We find little evidence for the conservation of transcription profiles between S. ratti and S. stercoralis or C. elegans. CONCLUSION: This is the first multi-gene study of gene expression in S. ratti. This has shown that robust data can be generated, with consistent measures of expression within computationally determined clusters and contigs. We find inconsistencies between EST representation data and microarray hybridization data in the identification of genes with stage-specific expression and highly expressed genes. Many of the genes whose expression is significantly different between L1 and iL3s stages are unknown beyond alignments to predicted genes. This highlights the forthcoming challenge in actually determining the role of these genes in the life of S. ratti.

Animals↗

Protein quality control in the bacterial periplasm.

The proper functioning of extracytoplasmic proteins requires their export to, and productive folding in, the correct cellular compartment. All proteins in Escherichia coli are initially synthesized in the cytoplasm, then follow a pathway that depends upon their ultimate cellular destination. Many proteins destined for the periplasm are synthesized as precursors carrying an N-terminal signal sequence that directs them to the general secretion machinery at the inner membrane. After translocation and signal sequence cleavage, the newly exported mature proteins are folded and assembled in the periplasm. Maintaining quality control over these processes depends on chaperones, folding catalysts, and proteases. This article summarizes the general principles which control protein folding in the bacterial periplasm by focusing on the periplasmic maltose-binding protein.

Journal Article↗

The role of wages in the migration of health care professionals from developing countries.

Several countries are increasingly relying on immigration as a means of coping with domestic shortages of health care professionals. This trend has led to concerns that in many of the source countries - especially within Africa - the outflow of health care professionals is adversely affecting the health care system. This paper examines the role of wages in the migration decision and discusses the likely effect of wage increases in source countries in slowing migration flows.This paper uses data on wage differentials in the health care sector between source country and receiving country (adjusted for purchasing power parity) to test the hypothesis that larger wage differentials lead to a larger supply of health care migrants. Differences in other important factors affecting migration are discussed and, where available, data are presented.There is little correlation between the supply of health care migrants and the size of the wage differential between source and destination country. In cases where data are available on other factors affecting migration, controlling for these factors does not affect the result.At current levels, wage differentials between source and destination country are so large that small increases in health care wages in source countries are unlikely to affect significantly the supply of health care migrants. The results suggest that non-wage instruments might be more effective in altering migration flows.

Journal Article↗

The retrovirus RNA trafficking granule: from birth to maturity.

Post-transcriptional events in the life of an RNA including RNA processing, transport, translation and metabolism are characterized by the regulated assembly of multiple ribonucleoprotein (RNP) complexes. At each of these steps, there is the engagement and disengagement of RNA-binding proteins until the RNA reaches its final destination. For retroviral genomic RNA, the final destination is the capsid. Numerous studies have provided crucial information about these processes and serve as the basis for studies on the intracellular fate of retroviral RNA. Retroviral RNAs are like cellular mRNAs but their processing is more tightly regulated by multiple cis-acting sequences and the activities of many trans-acting proteins. This review describes the viral and cellular partners that retroviral RNA encounters during its maturation that begins in the nucleus, focusing on important events including splicing, 3' end-processing, RNA trafficking from the nucleus to the cytoplasm and finally, mechanisms that lead to its compartmentalization into progeny virions.

Alternative Splicing↗

Death and help expected from nurses when dying.

This project was undertaken to ascertain the perceptions of a group of Taiwan's fourth-year bachelor of science in nursing (BSN) students regarding death and help expected from nurses during the dying process. Within the Chinese culture, death is one of the most important life issues. However, in many Chinese societies it is difficult for people to reveal their deepest feelings to their significant others or loved ones. It was in this context that this project was developed because little is known about how Taiwan's nursing students perceive death and the dying process. Using an open-ended, self-report questionnaire, 110 senior BSN students recorded their thoughts on: (1) their fears before physical death; (2) afterlife destinations; and (3) the help they would expect from nurses when dying. The data were analyzed using a three-layer qualitative thematic analysis. The students' reported needs during the dying process were directed towards three main goals: (1) help in reaching the 'triple targets of individual life'; (2) help in facilitating in-depth support so that both the dying person and significant others can experience a blessed farewell; and (3) help in reaching a destination in the afterlife. The results support the belief of dying as a transition occurring when life weans itself from the mortal world and prepares for an afterlife.

Adult↗

Neural control of the sequence of expression of myosin heavy chain isoforms in foetal mammalian muscles.

The expression of myosin isoforms was studied during development of calf muscles in foetal and neonatal rats, using monoclonal antibodies against slow, embryonic and neonatal isoforms of myosin heavy chain (MHC). Primary myotubes had appeared in all prospective rat calf muscles by embryonic day 16 (E16). On both E16 and E17, primary myotubes in all muscles with the exception of soleus stained for slow, embryonic and neonatal MHC isoforms; soleus did not express neonatal MHC. In earlier stages of muscle formation staining for the neonatal isoform was absent or faint. Secondary myotubes were present in all muscles by E18, and these stained for both embryonic and neonatal MHCs, but not slow. In mixed muscles, primary myotubes destined to differentiate into fast muscle fibres began to lose expression of slow MHC, and primary myotubes destined to become slow muscle fibres began to lose expression of neonatal MHC. This pattern was further accentuated by E19, when many primary myotubes stained for only one of these two isoforms. Chronic paralysis or denervation from E15 or earlier did not disrupt the normal sequence of maturation of primary myotubes up until E18, but secondary myotubes did not form. By E19, however, most primary myotubes in aneural or paralyzed tibialis anterior muscles had lost expression of slow MHC and expressed only embryonic and neonatal MHCs. Similar changes occurred in other muscles, except for soleus which never expressed neonatal MHC, as in controls. Paralysis or denervation commencing later than E15 did not have these effects, even though it was initiated well before the period of change in expression of MHC isoforms. In this case, some secondary myotubes appeared in treated muscles. Paralysis initiated on E15, followed by recovery 2 days later so that animals were motile during the period of change in expression of MHC isoforms, was as effective as full paralysis. These experiments define a critical period (E15-17) during which foetuses must be active if slow muscle fibres are to differentiate during E19-20. We suggest that changes in expression of MHC isoforms in primary myotubes depend on different populations of myoblasts fusing with the myotubes, and that the normal sequence of appearance of these myoblasts has a stage-dependent reliance on active innervation of foetal muscles. A critical period of nerve-dependence for these myoblasts occurs several days before their action can be noted.

Animals↗

Hox-7 expression during murine craniofacial development.

We have used in situ hybridisation to establish the temporal and spatial expression patterns of the mouse homeobox-containing gene; Hox-7, in the developing embryonic cranium and nervous system of the mouse between embryonic days 9.5 (E9.5) and E15.5. Hox-7 has previously been associated with areas of mesenchymal-epithelial interaction and cell migration especially in neural crest ectomesenchymal cells. Aside from the expression patterns seen in the facial anlage at E9.5, Hox-7 transcripts were also detected in the neuroepithelium including cells of the dorsal midline of the neural tube. This expression pattern persisted throughout the embryonic time span studied. At E11.5, expression of Hox-7 became obvious in the neuroepithelium of the forming tela choroida and the telencephelii in areas destined to form the choroid plexus before any atrophy of the neuroepithelium took place. High expression of Hox-7 was also present in the mesenchyme cells invading the pouch formed by the involuting choroid plexus neuroepithelium. A second major site where Hox-7 was expressed was the anlage of the anterior pituitary; the Rathke's pouch. Expression became obvious at E10.5 throughout the pouch but by E12.5 became more regionalised in areas of the pouch destined to form the pars distalis. Hox-7 was also expressed in the forming meninges and skull bone precursors from E10.5 onwards. Expression of the Hox-7 gene is also seen in the external ear, the forming eye, the nasal pits and forming Jacobson's organs. When these expression patterns are considered together with characterised human and mouse retinoic acid embryopathies and the congenital malformations seen in human children associated with deletion of chromosome 4p16.1 (Wolf-Hirschhorn syndrome), Hox-7 may be a good candidate as one of the genes involved in the initiation of the choroid plexus phenotype and its subsequent formation, the formation of the outer ear, formation of the dentition and the differentiation of the cell types of the anterior pituitary. The expression pattern of Hox-7 in the dorsal midline of the neural tube further suggests that it may also be involved in the specification of the dorsal-ventral axis of the developing nervous system.

Animals↗

Fates and migratory routes of primitive streak cells in the chick embryo.

We have used carbocyanine dyes to fate map the primitive streak in the early chick embryo, from stages 3+ (mid-primitive streak) to 9 (8 somites). We show that presumptive notochord, foregut and medial somite do not originate solely from Hensen's node, but also from the anterior primitive streak. At early stages (4- and 4), there is no correlation between specific anteroposterior levels of the primitive streak and the final position of their descendants in the notochord. We describe in detail the contribution of specific levels of the primitive streak to the medial and lateral halves of the somites. To understand how the descendants of labelled cells reach their destinations in different tissues, we have followed the movement of labelled cells during their emigration from the primitive streak in living embryos, and find that cells destined to different structures follow defined pathways of movement, even if they arise from similar positions in the streak. Somite and notochord precursors migrate anteriorly within the streak and pass through different portions of the node; this provides an explanation for the segregation of notochord and somite territories in the node.

Animals↗

The orderly allocation of mesodermal cells to the extraembryonic structures and the anteroposterior axis during gastrulation of the mouse embryo.

The prospective fate of cells in the primitive streak was examined at early, mid and late stages of mouse gastrula development to determine the order of allocation of primitive streak cells to the mesoderm of the extraembryonic membranes and to the fetal tissues. At the early-streak stage, primitive streak cells contribute predominantly to tissues of the extraembryonic mesoderm as previously found. However, a surprising observation is that the erythropoietic precursors of the yolk sac emerge earlier than the bulk of the vitelline endothelium, which is formed continuously throughout gastrula development. This may suggest that the erythropoietic and the endothelial cell lineages may arise independently of one another. Furthermore, the extraembryonic mesoderm that is localized to the anterior and chorionic side of the yolk sac is recruited ahead of that destined for the posterior and amnionic side. For the mesodermal derivatives in the embryo, those destined for the rostral structures such as heart and forebrain mesoderm ingress through the primitive streak early during a narrow window of development. They are then followed by those for the rest of the cranial mesoderm and lastly the paraxial and lateral mesoderm of the trunk. Results of this study, which represent snapshots of the types of precursor cells in the primitive streak, have provided a better delineation of the timing of allocation of the various mesodermal lineages to specific compartments in the extraembryonic membranes and different locations in the embryonic anteroposterior axis.

Allantois↗

Retinoid signaling is essential for patterning the endoderm of the third and fourth pharyngeal arches.

The requirement of retinoic acid (RA) in the initial formation of the pharyngeal arches was investigated by treating headfold-stage mouse embryos with a pan-RAR antagonist in vitro and in vivo. This results in a complete absence of mesenchyme, arteries, nerves and epibranchial placodes of the 3rd and 4th pharyngeal arches, complete agenesis of the 3rd and 4th pouches and consistent lack of the 6th arch artery. Mesodermally derived endothelial cells are absent from the 3rd and 4th pharyngeal arch region and the distribution domain of EphA2 transcripts in mesodermal cells is shifted caudally. In situ hybridization with CRABPI, kreisler and EphA4 probes and the pattern of expression of a Wnt1-lacZ transgene show that neural crest cells (NCC) normally destined to the 3rd and 4th arches migrate ectopically. Most interestingly, the appearance of the 3rd and 4th arches is prevented by the antagonist only during a very narrow window of time, which does not correspond to the period of post-otic NCC migration. Both the timing of appearance and the nature of the defects in RAR antagonist-treated embryos indicate that migrating NCC and mesodermal cells destined to the caudal pharyngeal arches do not represent primary targets of RA action. Alterations in the endodermal expression pattern of Hoxa1, Hoxb1, Pax1, Pax9, Fgf3 and Fgf8 in response to the antagonist-induced block in RA signal transduction demonstrate for the first time that RA signaling is indispensable for the specification of the pharyngeal endoderm and suggest that this signaling is necessary to provide a permissive environment locally for the migration of NCC and mesodermal cells. Our study also indicates that the formation of the 2nd pharyngeal arch and that of the 3rd and 4th pharyngeal arches probably involve distinct RA-dependent developmental processes.

Animals↗

Coupled transport of p24 family members.

Recent studies show that small trans-membrane proteins of approximately 22-24 kDa (the p24 family), which are grouped into 4 sub-families by sequence homology (p23, p24, p25 and p26), are involved in the early secretory pathway. In this study, we have investigated the mutual requirements of ectopically expressed members of the p24 family for targeting to their proper cellular destination. We find that coexpression of p23 and p24 is both necessary and sufficient for each protein to be transported to the cis-Golgi network/Golgi complex. Proteins from other subfamilies did not substitute for either p23 or p24, even after multiple coexpression. However, trafficking of the p23/p24 couple was facilitated by coexpression of proteins from other sub-families. In addition, we find that the sequence resembling an endoplasmic reticulum retrieval signal present in the cytoplasmic domain of p23 (but not p24) is dispensable. In contrast, the conserved coiled-coil region in the lumenal domain is absolutely required in both p23 and p24 for proper targeting of the p23/p24 couple. These data demonstrate that p23 and p24 must interact with each other to reach their destination, but that this strict requirement is combined with a mutual dependence amongst p24 proteins. We speculate that p24 proteins can form different oligomeric complexes, which contribute to confer specialized sorting/trafficking properties to membranes of the early secretory pathway, perhaps serving as membrane organizers.

Amino Acid Sequence↗

ALT-associated PML bodies are present in viable cells and are enriched in cells in the G(2)/M phase of the cell cycle.

Telomere maintenance is essential for the unlimited proliferative potential of human cells, and hence immortalization. However, a number of tumors, tumor-derived cell lines and in vitro immortalized cell lines have been described that do not express detectable telomerase activity. These lines utilize a mechanism, termed Alternative Lengthening of Telomeres (ALT), to provide telomere maintenance. A subset of the cells in each ALT cell line contain a novel form of the promyelocytic leukemia nuclear body (PML NB) in which telomeric DNA and the telomere binding proteins TRF1 and TRF2 co-localize with the PML protein, termed ALT-associated PML bodies (AA-PBs). In contrast, in non-ALT, telomerase-positive cell lines these telomeric proteins and the PML NB occupy distinct and separate subnuclear domains. PML NBs have been implicated in terminal differentiation, growth suppression and apoptosis. The role, if any, of AA-PBs in telomere maintenance or culture viability in telomerase negative cell lines is unclear, but it has been suggested that cells containing these structures are no longer viable and are marked for eventual death. We utilized a series of human ovarian surface epithelium (HOSE) cell lines that use ALT for telomere maintenance to determine if AA-PBs are indeed markers of cells in these cultures that are no longer cycling. We show that AA-PB positive cells incorporate BrdU and thus are able to carry out DNA replication. In addition, AA-PBs are present in mitotic cells and the frequency of cells containing these structures is increased when cultures are enriched for cells in the G(2)/M phase of the cell cycle suggesting that the formation of AA-PBs is coordinately regulated with the cell cycle. Finally, we demonstrate that the majority of the AA-PB positive cells in the culture are not destined for immediate apoptosis. Taken together the data argue against AA-PBs marking cells destined for death and, instead, raise the possibility that these structures may be actively involved in telomere maintenance via the ALT pathway.

Cell Cycle↗

The molecular mechanism of organelle transport along microtubules: the identification and characterization of KIFs (kinesin superfamily proteins).

In the cells various kinds of organelles are transported and distributed to their proper destinations in the cell. Organelle transports are very important for cellular morphogenesis and functions, with the conveying and targeting of essential materials to their correct destination being conducted, often at considerable velocities. Recently we have identified at least 10 new microtubule-associated motor proteins named as KIFs (kinesin superfamily proteins). Their characterization reveals that each member can convey a specific organelle or cargo, although there is some redundancy. It has also become clear that there are distinct subclasses of KIFs that form monomeric, heterodimeric and homodimeric motors. Molecular cell biological approaches combining multidisciplinary methods such as new electron microscopy, biochemistry, immunocytochemistry, biophysics, molecular biology and molecular genetics have revealed precise mechanisms of organelle transports in the cells by KIFs.

Animals↗

Neighborhood environmental factors correlated with walking near home: Using SPACES.

PURPOSE: The physical environment plays an important role in influencing participation in physical activity, although the specific factors that are correlated with different patterns of walking remain to be determined. We examined correlations between physical environmental factors and self-reported walking for recreation and transport near home. METHODS: The local neighborhood environments (defined as a 400-m radius from the respondent's home) of 1678 adults were assessed for their suitability for walking. The environmental data were collected during 2000 using the Systematic Pedestrian and Cycling Environmental Scan (SPACES) instrument together with information from other sources. We used logistic regression modeling to examine the relationship between the attributes of the physical environment and the self-reported walking behavior undertaken near home. RESULTS: Functional features were correlated with both walking for recreation (odds ratio (OR) 1.62; 95% confidence interval (CI): 1.20-2.19) and for transport (OR 1.30; 95% CI: 0.97-1.73). A well-maintained walking surface was the main functional factor associated with walking for recreation (OR 2.04; 95% CI: 1.43-2.91) and for transport (OR 2.13; 95% CI: 1.53-2.96). Destination factors, such as shops and public transport, were significantly correlated with walking for transport (OR 1.80; 95% CI: 1.33-2.44), but not recreation. CONCLUSION: The findings suggest that neighborhoods with pedestrian facilities that are attractive and comfortable and where there are local destinations (such as shops and public transport) are associated with walking near home.

Adult↗

Neighborhood Environment Walkability Scale: validity and development of a short form.

PURPOSE: The aim of this study was to examine the factorial and criterion validity of the Neighborhood Environment Walkability Scale (NEWS) and to develop an abbreviated version (NEWS-A). METHODS: A stratified two-stage cluster sample design was used to recruit 1286 adults. The sample was drawn from residential addresses within eight high- and eight low-walkable neighborhoods matched for socioeconomic status. Subjects completed the NEWS and reported weekly minutes of walking for transport and recreation using items from the International Physical Activity Questionnaire. RESULTS: Multilevel confirmatory factor analysis was used to develop measurement models of the NEWS and NEWS-A. Six individual-level and five blockgroup-level factors were identified. Factors/scales gauging presence of diversity of destinations, residential density, walking infrastructure, aesthetics, traffic safety, and crime were positively related to walking for transport. Aesthetics, mixed destinations, and residential density were associated with walking for recreation. CONCLUSIONS: The NEWS and NEWS-A possess adequate levels of factorial and criterion validity. Alternative methods of scoring for different purposes are presented.

Adult↗

Travels with HIV: the compliance and health of HIV-infected adults who travel.

We examined the effects of travel on the health of a group of HIV-infected adults (n = 89) cared for in a public hospital HIV clinic. In a period of 2 years, 45% travelled to a median of 3 US destinations for at least one week and 20% travelled to at least one international destination for a mean duration of 20 days. At the time of completion of the survey, the majority of these patients were severely immunosuppressed (median CD4+ count, 120/mm3). A physician was consulted concerning travel before 53% of the trips, but only one person consulted a travel medicine expert. All but one patient (98%) who was receiving medical therapy carried sufficient supplies of medication; 95% estimated their compliance with medication at 75% or better. None of the travellers to developing countries received gamma globulin, but one received yellow fever vaccine. Fifteen travellers (43%) became ill either during their trip or immediately thereafter; 3 required hospitalization. While most illnesses were not severe, 4 patients developed potentially life-threatening infections including coccidioidomycosis, cryptococcosis, PCP, and bacterial pneumonia. This survey provides information by which the clinician can anticipate the health care needs of HIV-infected patients who travel. HIV-infected patients should be more aware of the necessity for medical counsel prior to travel.

AIDS-Related Opportunistic Infections↗

Development of a versatile expression plasmid construction system for Aspergillus oryzae and its application to visualization of mitochondria.

We report here a development of the MultiSite Gateway(TM)-based versatile plasmid construction system applicable for the rapid and efficient preparation of Aspergillus oryzae expression plasmids. This system allows the simultaneous connection of the three DNA fragments inserted in entry clones along with a destination vector in a defined order and orientation. We prepared a variety of entry clones and destination vectors containing promoters, genes encoding carrier-proteins and fusion tags, and selectable markers, which makes it possible to generate 80 expression plasmids for each target protein. Using this system, plasmids for expression of the EGFP fused with the mitochondrial-targeting signal of citrate synthase (AoCit1) were generated. Tubular structures of mitochondria were visualized in the transformants expressing the AoCit1-EGFP fusion protein. This plasmid construction system allows us to prepare a large number of expression plasmids without laborious DNA manipulations, which would facilitate molecular biological studies on A. oryzae.

Aspergillus oryzae↗

Neurostimulant medication usage during stroke rehabilitation: the Post-Stroke Rehabilitation Outcomes Project (PSROP).

Motor recovery after a stroke depends upon many upon different modalities. Intensive therapy using compensatory and facilitatory techniques is the primary method to improve movement and function in affected extremities. However, medications used to modulate neurotransmitters may be useful in augmenting therapy approaches. The Post-Stroke Rehabilitation Outcomes Project (PSROP) database was used to describe the frequency of prescribing neurostimulant medications; the types of neurostimulant medications used; and how the use of neurostimulant medications affected rehabilitation length of stay, motor recovery, cognitive recovery, and discharge destination. Of the 1,161 patients in the PSROP database, 929 (80.0%) patients did not receive any treatment with methylphenidate, modafinil, levodopa, amantadine, or bromocriptine. Patients who received neurostimulant medications did not have any more significant changes in length of stay, motor recovery, cognitive recovery, or discharge destination than patients who did not receive neurostimulant medications. Much research needs to be completed before clinicians know precisely whether and how rehabilitation therapies and medications interact to assist in functional recovery.

Aged↗